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Background: High-risk (HR) human papillomavirus (HPV) infection is an established cause of malignant disease. We used a societal perspective to estimate the cost of HR HPV-related cervical, vulvar, vaginal, anal, and penile precancer and cancer, and oropharyngeal cancer in Sweden in 2006, 1 year before HPV vaccination became available in the country., Materials and Methods: This prevalence-based cost-of-illness study used diagnosis-specific data from national registries to determine the number of HR HPV-related precancers and cancers. The HR HPV-attributable fractions of these diseases were derived from a literature review and applied to the total burden to estimate HR HPV-attributable costs. Direct costs were based on health care utilization and indirect costs on loss of productivity due to morbidity (i.e., sick leave and early retirement) and premature mortality., Results: The total annual cost of all HR HPV-attributable precancers and cancers was €94 million (€10.3/inhabitant). Direct costs accounted for €31.3 million (€3.4/inhabitant) of the total annual cost, and inpatient care amounted to €20.7 million of direct costs. Indirect costs made up €62.6 million (€6.9/inhabitant) of the total annual cost, and premature mortality amounted to €36 million of indirect costs. Cervical precancer and cancer was most costly (total annual cost €58.4 million). Among cancers affecting both genders, anal precancer and cancer, and oropharyngeal cancer were the most costly (€11.2 million and €11.9 million, respectively). For oropharyngeal cancer, males had the highest health care utilization and represented 71% of the total annual cost. Penile precancer and cancer was least costly (€2.6 million)., Conclusion: The economic burden of HR HPV-related precancers and cancers is substantial. The disease-related management and treatment costs we report are relevant as a point of reference for future economic evaluations investigating the overall benefits of HPV vaccination in females and males in Sweden.

Background: Russian suicide mortality rates changed rapidly over the second half of the twentieth century. This study attempts to differentiate between underlying period and cohort effects in relation to the changes in suicide mortality in Russia between 1956 and 2005., Methods: Sex- and age-specific suicide mortality data were analyzed using an age-period-cohort (APC) approach. Descriptive analyses and APC modeling with log-linear Poisson regression were performed., Results: Strong period effects were observed for the years during and after Gorbachev's political reforms (including the anti-alcohol campaign) and for those following the break-up of the Soviet Union. After mutual adjustment, the cohort- and period-specific relative risk estimates for suicide revealed differing underlying processes. While the estimated period effects had an overall positive trend, cohort-specific developments indicated a positive trend for the male cohorts born between 1891 and 1931 and for the female cohorts born between 1891 and 1911, but a negative trend for subsequent cohorts., Conclusions: Our results indicate that the specific life experiences of cohorts may be important for variations in suicide mortality across time, in addition to more immediate effects of changes in the social environment.

Objective: To determine the incidence and occupational variation of granulosa cell tumours (GCTs) in Finland, Iceland, Norway and Sweden over a 60-year period, 1953-2012., Design: A longitudinal cohort study., Setting and Population: Finland, Iceland, Norway and Sweden and a total of 249 million women over a 60-year period (1953-2012). The NOCCA (Nordic Occupational Cancer Study) included 6.4 million women with 776 incident GCT cases diagnosed until the end of follow up., Methods: Incidence rates were calculated from the national cancer registries and compared using quasi-Poisson regression models. Occupation-specific standardised incidence ratios (SIRs) were calculated from the Nordic Occupational Cancer (NOCCA) database., Main Outcome Measures: Incidence rates and standardised incidence ratios., Results: The age-adjusted (World Standard) incidence rates remained quite constant: about 0.6-0.8 per 100 000 for most of the study period. The age-specific incidence was highest at 50-64 years of age. There were no occupations with significantly increased risk of GCT. Major changes in the use of oral contraceptives, postmenopausal hormonal therapy, fertility rate and lifestyle in general during the study period and among different occupational categories do not appear to have a marked effect on the incidence of GCT., Conclusion: Our findings support the concept of GCT as a primarily sporadic, not exposure-related, cancer., Tweetable Abstract: The Nordic incidence rates of GCTs show stability over time and among different occupational categories., (© 2016 Royal College of Obstetricians and Gynaecologists.)

Objectives: Comprehensive nationwide monitoring and evaluation of screening through registry-based review of key indicators is necessary for programme optimization, especially as new tests and strategies are introduced. We aimed to investigate and report on the use of these key indicators in the Swedish programme., Setting and Methods: Organized population-based cervical screening targeting women aged 23-50 and 51-60 every three and five years, respectively, is regionally implemented in Sweden. All cytological and histopathological test results and invitations are exported to the National Cervical Screening Registry. We describe the methods to obtain registry-based quality indicators by age, region, and calendar period., Results: In 2013, there were 633,592 cervical smears in Sweden, of which 69% were organized smears resulting from an invitation. Screening test coverage for women aged 23-60 was 80% and similar for the previous decade, but varied greatly between and within counties over-time. Among women aged 23-25, test coverage increased dramatically during the previous six years, reaching 87% in 2013. The proportion of women with cytological high-grade cervical lesions found in cytology that had been followed-up with biopsy within one year was 97%. Major variations in cervical cancer incidence between counties were observed., Conclusions: Registry-based analyses of key quality indicators provided the basis for prioritizing improvements of the organized cervical screening programme., (© The Author(s) 2016.)

Little is known about the incidence and risk of cervical intraepithelial neoplasia (CIN) grade 3, adenocarcinoma in situ and invasive cervical cancer (CIN3+) among migrants living with HIV in a European setting. We assessed the cumulative incidence (CuI) and hazard ratio (HR) of CIN2+ and CIN3+ in a cohort of women living with HIV (WLWH) (n = 893) identified from the Swedish national HIV register and HIV-negative women (n = 205,842) identified from the Swedish Population Register, matched on region of birth and age. Data was collected between 1993 and 2011 by linking our cohort with the Swedish National Cervical Screening Registry, collecting all cytological and histological results since 1993. The CuI of CIN3+ was 13.1% [95% confidence interval (CI) 8.9-17.2] for WLWH and 2.1% (95% CI 2.0-2.2) for HIV-negative after 18 years of follow-up. WLWH had more than eight times higher, age and region of birth matched, risk of CIN3+ than HIV-negative (HR 8.8: 95% CI 6.9-11.3). WLWH born in the East region, dominated by Thai women, had a two times higher risk of CIN3+ compared with WLWH born in Sweden (HR 2.47: 95% CI 1.2-5.0), which remained after adjusting for immunosuppression. Our results showed a substantially increased risk of CIN3+ among WLWH, which differed depending on birth region. Early HIV diagnosis and attendance to cervical cancer screening, with focus on migrants, is of crucial importance to minimize the incidence of cervical intraepithelial neoplasia., (© 2016 UICC.)

Objectives: We updated the Swedish component of the Nordic Occupational Cancer (NOCCA) Study through 2009 in order to investigate the incidence of mesothelioma of the peritoneum and pleura in both genders, and explored occupational exposures that may be associated with mesothelioma., Methods: The Swedish component of the NOCCA Study includes 6.78 million individuals. Data from this cohort were linked to the population-based Swedish Cancer Registry and Swedish Total Population Registry for three periods between 1961 and 2009, and then further linked to the Swedish NOCCA job-exposure matrix, which includes 25 carcinogenic substances and the corresponding exposure levels for 280 occupations. Multivariate analysis was used to calculate standardized incidence ratios (SIRs) for mesothelioma of the peritoneum and pleura by gender, occupational category, carcinogenic substance, and for multiple occupational exposures simultaneously., Results: A total of 3,716 incident mesotheliomas were recorded (21.1% in women). We found a significantly increased risk of mesothelioma in 24 occupations, as well as clear differences between the genders. Among men, increased risks of mesothelioma of the pleura were observed in male-dominated occupations, with the greatest elevation of risk among plumbers (SIR, 4.99; 95% confidence interval, 4.20 to 5.90). Among women, increased risks were observed in sewing workers, canning workers, packers, cleaners, and postal workers. In multivariate analysis controlling for multiple occupational exposures, significant associations were only observed between asbestos exposure and mesothelioma., Conclusions: Asbestos exposure was associated with mesothelioma incidence in our study. The asbestos ban of 1982 has yet to show any clear effect on the occurrence of mesothelioma in this cohort. Among women, the occupations of canning workers and cleaners showed increased risks of mesothelioma of the pleura without evidence of asbestos exposure., Competing Interests: The authors have no conflicts of interest to declare for this study.

Background: Genital chlamydia infection (chlamydia) is the most commonly reported sexually transmitted infection (STI) in Sweden. To guide prevention needs, we aimed to investigate factors associated with chlamydia., Methods: A cohort of visitors aged 20-40 years at an urban STI clinic in Sweden was recruited. Behavioural data were collected using a self-administered questionnaire. Self-sampled specimens were tested for chlamydia by a DNA amplification assay. Statistically significant (p<0.05) and epidemiologically relevant covariates were entered in a multivariate Poisson model adjusted for potential confounders (age and gender). Backward stepwise elimination produced a final model. Multiple imputation was used to account for missing values., Results: Out of 2814 respondents, 1436 were men with a chlamydia positivity rate of 12.6% vs 8.9% in women. Lifetime testing for chlamydia and HIV was high (82% and 60%, respectively). Factors significantly associated with chlamydia were: 20-24 years old (adjusted risk ratio (ARR)=2.10, 95% CI 1.21 to 3.65); testing reason: contact with a chlamydia case (ARR=6.55, 95% CI 4.77 to 8.98) and having symptoms (ARR=2.19, 95% CI 1.48 to 3.24); 6-10 sexual partners (ARR=1.53, 95% CI 1.06 to 2.21); last sexual activity 'vaginal sex and oral sex and anal sex and petting' (ARR=1.84, 95% CI 1.09 to 3.10); alcohol use before sex (ARR=1.98, 95% CI 1.10 to 3.57); men with symptoms (ARR=2.09, 95% CI 1.38 to 3.18); tested for chlamydia (ARR=0.72, 95% CI 0.55 to 0.94)., Conclusions: Risk factors associated with chlamydia were consistent with previous reports in similar settings and suggest no major changes over time. Increased risk for chlamydia infection associated with high-risk behaviour (eg, alcohol use, increased number of sexual partners) supports the need for behavioural interventions in this population such as promotion of safer sex behaviour (condom use) and testing., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Objectives: To examine screening patterns and the risk of cervical neoplasia in women with rheumatoid arthritis (RA) treated or not with tumour necrosis factor inhibitors (TNFi)., Methods: We performed a nationwide register-based cohort study in Sweden of women with RA who started a first TNFi (n=9629), biologics-naive women with RA (n=34 984) and general population comparators (matched 1:10, n=300 331), followed up from 1999 to 2012. Outcomes were first cytology screening with normal outcome, first ever cervical intraepithelial neoplasia (CIN) grade 1, first ever CIN 2-3 or adenocarcinoma in situ and first ever invasive cervical cancer during follow-up. HRs were assessed through Cox regressions adjusted for age, educational level, prior cervical screens, comorbidities, marital status and prior hospitalisations., Results: Biologic-naive women with RA had more screenings (HR 1.08, 95% CI 1.06 to 1.10), were at greater risk of CIN 1 (HR 1.53, 1.23 to 1.89) and CIN 2-3 (HR 1.39, 1.16 to 1.66), but not of invasive cervical cancer (HR 1.09, 0.71 to 1.65) compared with the general population. Patients who initiated TNFi therapy had similar screening patterns (HR 1.01, 0.98 to 1.05), were not at increased risk of CIN 1 (HR 1.23, 0.87 to 1.74), but were at increased risk of CIN 2-3 (HR 1.36, 1.01 to 1.82) and invasive cervical cancer (HR 2.10, 1.04 to 4.23) compared with biologics-naive women with RA. Estimates varied little with successive adjustments, but were attenuated/absent in sensitivity analyses restricted to 2006-2012 and a disease-modifying antirheumatic drugs-treated comparator., Conclusions: Women with RA in general are at elevated risk of cervical dysplasia. Compared with biologics-naive patients, women treated with TNFi are at increased risk of cervical cancer. Whether this increase is causally linked with TNFi could not be fully disentangled., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Human papillomavirus (HPV) types 16/18, included in HPV vaccines, contribute to the majority of cervical cancer, and a substantial proportion of cervical intraepithelial neoplasia (CIN) grades 2/3 or worse (CIN2+/CIN3+) including adenocarcinoma in situ or worse. The aim of this study was to quantify the effect of quadrivalent HPV (qHPV) vaccination on incidence of CIN2+ and CIN3+. A nationwide cohort of girls and young women resident in Sweden 2006-2013 and aged 13-29 (n = 1,333,691) was followed for vaccination and histologically confirmed high-grade cervical lesions. Data were collected using the Swedish nationwide healthcare registers. Poisson regression was used to calculate incidence rate ratios (IRRs) and vaccine effectiveness [(1-IRR)x100%] comparing fully vaccinated with unvaccinated individuals. IRRs were adjusted for attained age and parental education, and stratified on vaccination initiation age. Effectiveness against CIN2+ was 64% (IRR = 0.36, 95%CI = 0.27–0.47) for those initiating vaccination before age 17, and 25% (IRR = 0.75, 95%CI = 0.66–0.86) and 14% (IRR = 0.86, 95%CI = 0.73–1.01) for those initiating vaccination at ages 17–19, and at ages 20–29, respectively. Vaccine effectiveness against CIN3+ was similar to vaccine effectiveness against CIN2+. Results were robust for both women participating to the organized screening program and for women at prescreening ages. We show high effectiveness of qHPV vaccination on CIN2+ and CIN3+ lesions, with greater effectiveness observed in girls younger at vaccination initiation. Continued monitoring of impact of HPV vaccination in the population is needed in order to evaluate both long-term vaccine effectiveness and to evaluate whether the vaccination program achieves anticipated effects in prevention of invasive cervical cancer., (© 2016 The Authors International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.)

Objectives: To investigate disease history before A(H1N1)pdm09 vaccination as a risk factor for narcolepsy., Methods: Case-control study in Sweden. Cases included persons referred for a Multiple Sleep Latency Test between 2009 and 2010, identified through diagnostic sleep centres and confirmed through independent review of medical charts. Controls, selected from the total population register, were matched to cases on age, gender, MSLT-referral date and county of residence. Disease history (prescriptions and diagnoses) and vaccination history was collected through telephone interviews and population-based healthcare registers. Conditional logistic regression was used to investigate disease history before A(H1N1)pdm09 vaccination as a risk-factor for narcolepsy., Results: In total, 72 narcolepsy cases and 251 controls were included (range 3-69 years mean19-years). Risk of narcolepsy was increased in individuals with a disease history of nervous system disorders (OR range = 3.6-8.8) and mental and behavioural disorders (OR = 3.8, 95% CI 1.6-8.8) before referral. In a second analysis of vaccinated individuals only, nearly all initial associations were no longer statistically significant and effect sizes were smaller (OR range = 1.3-2.6). A significant effect for antibiotics (OR = 0.4, 95% CI 0.2-0.8) and a marginally significant effect for nervous system disorders was observed. In a third case-only analysis, comparing cases referred before vaccination to those referred after; prescriptions for nervous system disorders (OR = 26.0 95% CI 4.0-170.2) and ADHD (OR = 35.3 95% CI 3.4-369.9) were statistically significant during the vaccination period, suggesting initial associations were due to confounding by indication., Conclusion: The findings of this study do not support disease history before A(H1N1)pdm09 vaccination as a risk factor for narcolepsy.

Background: The Swedish school-based vaccination programme offers HPV vaccine to girls born ≥1999 in 5-6th grade. In 2012, all counties introduced free-of-charge catch-up vaccination campaigns targeting girls born 1993-1998. Varying vaccine uptake in the catch-up group by December 2012 suggested that some implementation strategies were more successful than others. In order to inform future vaccination campaigns, we assessed the impact of different implementation strategies on the county-level catch-up vaccine uptake., Methods: We conducted an ecological study including all Swedish counties (n = 21), asking regional health offices about the information channels they used and where vaccination of the catch-up target group took place in their counties. The uptake of ≥1 dose by 30 September 2014 was estimated using data from the voluntary national vaccination register. We investigated associations between counties' catch-up vaccine uptake, information channels and vaccination settings by calculating incidence rate ratios (IRR) and 95% confidence intervals (CI), using negative binomial regression models., Results: County level catch-up vaccine uptake varied between 49-84%. All counties offered vaccination through primary health care settings. Apart from this eight (34%) also offered the vaccine in some of their schools, four (19%) in all their schools, and two (10%) in other health care centres. The information channels most frequently used were: information at the national on-line health care consulting web-page (100%), letter/invitations (90%), and advertisement (81%). Counties offering vaccination to girls in all schools and counties offering vaccination in some of their schools, reached higher vaccine uptake compared to counties not offering vaccination in any of their schools (all schools adjusted IRR: 1.3, 95% CI: 1.1-1.5, some schools adjusted IRR: 1.2, 95% CI: 1.1-1.3)., Conclusion: Counties offering HPV vaccination to catch-up groups in schools reached the highest vaccine uptake. No information channel explained differences in county-level vaccine uptake. Our findings suggest that catch-up vaccination outside the national vaccination program can reach a high uptake at the population level if it is implemented primarily with an organized delivery (e.g. in schools).

Background: Intra-generational social mobility, which describes the mobility within an individual's own working life, is seldom studied among employees with psychiatric disorders (EPD). There is need of knowledge of the intra-generational mobility patterns, in a broader perspective, among EPD., Aims: To investigate intra-generational social mobility in employed individuals diagnosed with affective disorder, personality disorder, schizophrenia and drug dependence in a national Swedish cohort., Method: We identified a national sample of employed Swedish adults born in 1939-1949 (N = 876, 738), and among them individuals with a first-time hospital admission for affective psychosis, neurosis and personality disorder, alcoholism, drug dependence or schizophrenia in 1964-1980 (N = 18, 998). Employed individuals without hospital admission for such diagnoses were utilised as a comparison group (N = 866, 442). Intra-individual social class changes between 1980 and 1990 among EPD and the comparison group were described through summary statistics and graphs., Results: EPD more often held Low manual occupations at baseline in 1980 than the comparison group (44% vs. 28%), although parental social class was similar. In 1990, 19% of EPD and 4% of the comparison group had lost contact with the labour market. Social stability was less common among EPD (49 %) than in the comparison group (67%). Mobility out of the labour force increased and social stability decreased by number of inpatient admissions. Employees diagnosed with affective psychosis or neurosis and personality disorder fared better in the labour market than employees with schizophrenia., Conclusion: Employees suffering from psychiatric disorder do not maintain their social class or remain in the labour force to the same extent as individuals without those problems, irrespective of their parental class. Our results support the social drift hypothesis that individuals with poor psychiatric health move downward in the social hierarchy., (© The Author(s) 2015.)

Objectives: To investigate the risks of invasive cervical cancer after detection of atypical glandular cells (AGC) during cervical screening., Design: Nationwide population based cohort study., Setting: Cancer and population registries in Sweden., Participants: 3,054,328 women living in Sweden at any time between 1 January 1980 and 1 July 2011 who had any record of cervical cytological testing at ages 23-59. Of these, 2,899,968 women had normal cytology results at the first screening record. The first recorded abnormal result was atypical glandular cells (AGC) in 14 625, high grade squamous intraepithelial lesion (HSIL) in 65 633, and low grade squamous intraepithelial lesions (LSIL) in 244 168., Main Outcome Measures: Cumulative incidence of invasive cervical cancer over 15.5 years; proportion of invasive cervical cancer within six months of abnormality (prevalence); crude incidence rates for invasive cervical cancer over 0.5-15.5 years of follow-up; incidence rate ratios compared with women with normal cytology, estimated with Poisson regression adjusted for age and stratified by histopathology of cancer; distribution of clinical assessment within six months after the abnormality., Results: The prevalence of cervical cancer was 1.4% for women with AGC, which was lower than for women with HSIL (2.5%) but higher than for women with LSIL (0.2%); adenocarcinoma accounted for 73.2% of the prevalent cases associated with AGC. The incidence rate of invasive cervical cancer after AGC was significantly higher than for women with normal results on cytology for up to 15.5 years and higher than HSIL and LSIL for up to 6.5 years. The incidence rate of adenocarcinoma was 61 times higher than for women with normal results on cytology in the first screening round after AGC, and remained nine times higher for up to 15.5 years. Incidence and prevalence of invasive cervical cancer was highest when AGC was found at ages 30-39. Only 54% of women with AGC underwent histology assessment within six months, much less than after HSIL (86%). Among women with histology assessment within six months, the incidence rate of cervical cancer after AGC was significantly higher than that after HSIL for up to 6.5 years., Conclusions: AGC found at cervical screening is associated with a high and persistent risk of cervical cancer for up to 15 years, particularly for cervical adenocarcinoma and women with AGC at age 30-39. Compared with the reduction in risk of cancer seen after HSIL management, management of AGC seems to have been suboptimal in preventing cervical cancer. Research to optimise management is needed, and a more aggressive assessment strategy is warranted., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Grief over the loss of a family member may cause physical and mental illness, but an association between bereavement and cancer risk has not been established. Based on the Swedish National Cervical Screening Register (1969-2011) including 14,011,269 smears from 2,466,107 women, we conducted two nested case-control studies to examine the associations of bereavement (i.e., loss of a family member due to death) with abnormal cytology (390,310 first abnormal and 1,951,319 normal smears) and in situ/invasive cervical cancer (75,128 case and 375,640 control women), both individually matched on year of birth and screening adherence. Among 1,696 of the control women, we further investigated bereavement in association with human papillomavirus (HPV) infection, both HPV16 and other HPV types. Bereavement was consistently associated with a 4% to 9% increased risk for first abnormal cytology, in situ and invasive cervical cancer (all P < 0.02). The associations became stronger when multiple losses, loss of child, sibling or spouse, and loss due to unnatural cause were analyzed separately (P for trend or difference < 0.0001), and for women with high screening adherence (P for difference < 0.05). Among 1,696 women who had not developed cervical cancer, we further investigated the link between bereavement and HPV infection. Bereavement was associated with a 62% increased risk of HPV16 infection, high viral load, and recurrent infection, and was also more strongly associated with HPV infections designated as high-risk compared with low-risk determinants of cervical carcinogenesis. Collectively, our findings demonstrate that bereavement is associated with an increased risk of developing cervical cancer. Further, they suggest that this association may be attributed to stress-induced oncogenic HPV infections., (©2015 American Association for Cancer Research.)

Background: More detailed understanding of herpes zoster (HZ) is called for in the context of an increasing observed frequency of disease, and ongoing discussions regarding potential consequences of the disease. Thus, population-based data on incidence and complications of HZ are needed., Methods: We conducted a register-based cohort study in Västra Götaland County (population 1.5 million) in Sweden. We collected data on all patients diagnosed with HZ during the years 2008 to 2010 from population-based registers. Incidence rates (IR) of HZ and related complications were calculated and stratified by age and sex., Results: There were 13 269 new HZ cases during the study period. Overall, the IR of herpes zoster in both genders was 3.25 (95% CI: 3.16-3.34) per 1000 person years in 2010. The incidence was consistently higher in women than in men and in older than in young. A history of immunosuppression was more common than in the general population. The incidence was highest in individuals over 80 years of age (IR 9.2 per 1000 person years, 95% CI: 8.8-9.6) during 2008-2010. The most common complications to HZ were ocular engagement and postherpetic neuralgia; risks for stroke and sepsis were significantly elevated during the one year following diagnosis, especially in the youngest age group of patients 0-39 years., Conclusions: Herpes zoster is more common in women, the elderly and immunosuppressed individuals. We verify a population-based association between herpes zoster and risk for stroke and sepsis, which may merit concern.

To assess associations between occupation and risk of oesophageal adenocarcinoma (AC) and squamous-cell carcinoma (SCC), data from the Nordic Occupational Cancer Study, a large population-based cohort with long-term follow-up, was used. The Nordic Occupational Cancer Study includes 12.9 million individuals aged 30-64 years who participated in national censuses in Finland, Iceland, Norway and Sweden in 1960-1990. Individuals were assigned to one of the 54 occupational categories, and individuals with oesophageal cancer were identified through nationwide cancer registries with follow-up through 2005. Country-specific standardised incidence ratios (SIRs) with 95% confidence intervals (CIs) were estimated. During follow-up, 4,722 ACs and 14,496 SCCs were observed. Among men, increased risks of AC and SCC were observed among waiters (SIR = 2.58, 95% CI 1.41-4.32 and SIR = 3.22, 95% CI 2.30-4.38 for AC and SCC, respectively), cooks and stewards (1.72, 1.04-2.69 and 2.53, 1.94-3.25), seamen (1.52, 1.16-1.95 and 1.77, 1.53-2.05), food workers (1.51, 1.18-1.90 and 1.21, 1.03-1.42), miscellaneous construction workers (1.24, 1.04-1.48 and 1.39, 1.25-1.54) and drivers (1.16, 1.01-1.33 and 1.23, 1.13-1.34). Decreased risks of AC and SCC were observed among technical workers, physicians, teachers, religious workers and gardeners. The SIR for AC was significantly different from that for SCC in six occupational categories. Among women, increased risks among food workers and waiters and decreased risks among teachers, nurses and assistant nurses were observed for SCC only. In both sexes, increased risks were observed among waiters and food workers, and decreased risks were observed among teachers. This large cohort study indicates that the risk of oesophageal cancer varies by occupation, but not by histological type in most occupational categories., (© 2014 UICC.)

Background: Concerns have been raised that HPV-vaccination might affect women's cervical screening behavior. We therefore investigated the association between opportunistic HPV-vaccination and attendance after invitation to cervical screening., Methods: A cohort of all women resident in Sweden, born 1977-1987 (N=629,703), and invited to cervical screening, was followed October 2006 - December 2012. Invitations to screening were identified via the National Quality Register for Cervical Cancer Prevention, as was the primary outcome of a registered smear. Vaccination status was obtained from two nationwide health data registers. Hazard ratios (HR) were estimated using Cox regression adjusted for age, education level and income (HRadj). Women were individually followed for up to 6 years, of which the first and second screening rounds were analyzed separately., Results: Screening attendance after three years of follow-up was 86% in vaccinated women (N=4,897) and 75% in unvaccinated women (N=625,804). The crude HR of screening attendance in vaccinated vs. unvaccinated women was 1.31 (95% CI 1.27-1.35) in the first screening round. Adjustment for education and income reduced but did not erase this difference (HRadj=1.09, 95% CI 1.05-1.13). In the second screening round, attendance was likewise higher in HPV-vaccinated women (crude HR=1.26, 95% CI 1.21-1.32; HRadj=1.15, 95% CI 1.10-1.20)., Conclusions: HPV-vaccination is so far associated with equal or higher attendance to cervical screening in Sweden in a cohort of opportunistically vaccinated young women. Most but not all of the difference in attendance was explained by socioeconomic differences between vaccinated and unvaccinated women. HPV vaccine effectiveness studies should consider screening attendance of HPV-vaccinated women when assessing incidence of screen-detected cervical lesions.

Introduction: Danish and Norwegian immigrant women in Sweden have an increased risk of cervical cancer compared to Swedish-born women. In addition, Danish and Norwegian immigrant women follow the national recommendations for attendance at cervical screening to much lesser extent than Swedish-born women. The aim of this study was to explore how Danish and Norwegian immigrant women in Sweden reason about attending cervical screening, focusing on women's perceptions as to why they and their compatriots do not attend., Methods: Eight focus group discussions (FGDs) were conducted with Danish and Norwegian immigrant women living in Stockholm. The women were between 26 and 66 years of age at the time of the FGDs, and were aged between <1 and 48 years old when they immigrated to Sweden. A FGD guide was used, which included questions related to cervical screening, and obstacles and motivators to attend cervical screening. The FGDs were tape recorded and transcribed, and the results analysed according to the principles of qualitative content analysis., Results: The main theme was "Women have a comprehensive rationale for postponing cervical screening, yet do not view themselves as non-attenders". Investigation of women's rationale for non-attendance after being invited to cervical screening revealed some complex reasons related to immigration itself, including competing needs, organisational and structural factors and differences in mentality, but also reasons stemming from other factors. Postponing attendance at cervical screening was the category that linked all these factors as the reasons to why women did not attend to cervical screening according to the recommendations of the authorities., Conclusions: The rationale used to postpone cervical screening, in combination with the fact that women do not consider themselves to be non-attenders, indicates that they have not actively taken a stance against cervical screening, and reveals an opportunity to motivate these women to attend.

Background: The clinical significance of co-infections with high-risk (HR) and low-risk (LR) human papillomavirus (HPV) in the etiology of cervical cancer is debated, as prospective evidence on this issue is limited. However, the question is of increasing relevance in relation to HPV-based cancer prevention., Methods: In two population-based nested case-control studies among women participating in cervical screening with baseline normal smears, we collected 4659 smears from women who later developed cancer in situ (CIS; n = 524) or squamous cervical cancer (SCC; n = 378) and individually matched control subjects who remained free of disease during study follow-up. The median follow-up until diagnosis was 6.4 to 7.8 years. All smears were tested for HPV. We used conditional logistic regression models with two-way interaction terms to estimate relative risks (RRs) for CIS and SCC, respectively. All statistical tests were two-sided., Results: Compared with women who were infected with HRHPV only, women who were also infected with LRHPV had a lower risk for SCC (RR = 0.2, 95% confidence interval [CI] = 0.04 to 0.99, P = .049). This interaction was not shown for CIS (RR = 1.1, 95% CI = 0.4 to 3.6). Women who were positive for both HRHPV and LRHPV had, on average, a 4.8 year longer time to diagnosis of SCC than women who were positive for HRHPV only (P = .006). Results were highly robust in sensitivity analyses., Conclusion: Co-infection with LRHPV is associated with a lower risk of future invasive disease and longer time to diagnosis than infection with HRHPV alone. We propose that co-infection with LRHPV interferes with the rate of progression to invasive cervical cancer., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Aims: To study cancer risk patterns among waiters in the Nordic countries., Methods: We identified a cohort of 16,134 male and 81,838 female waiters from Denmark, Finland, Iceland, Norway and Sweden. During the follow-up period from 1961 to 2005, we found that 19,388 incident cancer cases were diagnosed. Standardised incidence ratio (SIR) was defined as the observed number of cancer cases divided by the expected number, based on national age, time period and gender-specific cancer incidence rates in the general population., Results: The SIR of all cancers in waiters, in the five countries combined, was 1.46 (95% CI 1.41-1.51) in men and 1.09 (1.07-1.11) in women. In male waiters, the SIR decreased from 1.79 (1.63-1.96) in 1961-1975, to 1.33 (1.26-1.40) in 1991-2005, but remained stable among women. The SIR among male waiters was highest for cancers in the pharynx (6.11; 95% CI 5.02-7.37), oral cavity (4.91; 95% CI 3.81-6.24) and tongue (4.36; 95% CI 3.13-5.92); and in female waiters, in the larynx (2.17; 95% CI 1.63-2.82), oral cavity (1.96; 95% CI 1.60-2.34) and lung (1.89; 95% CI 1.80-1.99)., Conclusions: The risk of cancer among waiters was higher than in the general population. The elevated incidence in some cancer sites can likely be explained by higher alcohol consumption, the prevalence of smoking and occupational exposure to tobacco smoke. Hopefully, the incidence of cancer among waiters will decrease in the future, due to the banning of tobacco smoking in restaurants and bars in the Nordic countries., (© 2015 the Nordic Societies of Public Health.)

Objective: The aim of the current study was to assess the relation between occupational exposure to solvents and the risk of acute myeloid leukemia (AML)., Methods: Altogether, this study comprises 15 332 incident cases of AML diagnosed in Finland, Norway, Sweden and Iceland from 1961-2005 and 76 660 controls matched by year of birth, sex, and country. Occupational records were linked with Nordic Occupational Cancer Study job exposure matrix (JEM) to estimate quantitative values for 26 occupational exposure factors. Hazard ratios (HR) with 95% confidence intervals (95% CI) were estimated by using conditional logistic regression models., Results: We did not observe statistically significantly increased risk for exposure to any of the solvents. HR estimates for high levels of toluene (HR 1.35, 95% CI 0.74-2.46), aromatic hydrocarbon solvents (ARHC) (HR 1.18, 95% CI 0.76-1.86), and moderate-to-high levels of trichloroethylene were slightly but non-significantly elevated. We did not observe an association between benzene exposure and AML in this study., Conclusions: This study did not provide clear evidence for an association between occupational solvent exposure and AML. There was some indication for an excess risk in the groups of workers exposed to toluene, trichloroethylene and ARHC.

Background: We analyzed temporal trends in the incidence of myocardial infarction and ischemic stroke in Sweden by socioeconomic position and investigated whether social inequalities in incidence of these diseases changed over time., Materials and Methods: We studied a cohort of almost three million Swedish residents born between 1932 and 1960 followed from 1987 until 2010. Incident cases of myocardial infarction and ischemic stroke were identified in the Swedish National Inpatient Register and Cause of Death Register. Socioeconomic position was retrieved from the Population and Housing Censuses. Incidence rates of myocardial infarction and ischemic stroke and incidence rate ratios comparing levels of socioeconomic position were estimated using flexible parametric survival models adjusted for calendar year, attained age, sex, and birth country., Results: The overall incidences of myocardial infarction and ischemic stroke decreased over time among men, but were stable over time among women. With regard to ischemic stroke incidence, socioeconomic inequality increased over time in the age group 55 to 59: the incidence rate ratios for low manual compared to high non-manual increased from 1.3 (95% CI: 1.2-1.4) in 1997 to 1.5 (1.4-1.7) in 2010 among men, and from 1.4 (1.3-1.6) in 1997 to 2.1 (1.8-2.5) in 2010 among women. The socioeconomic inequality in incidence of myocardial infarction was stable over time for both men and women., Conclusion: There was a decrease in myocardial infarction and ischemic stroke incidence over time among men but no significant change for women. Our study highlights existing, and in some cases increasing, social inequalities in the incidence of cardiovascular diseases.

Background: Recent genome-wide association studies suggest some overlap of genetic determinants of ischemic stroke (IS) and myocardial infarction (MI). This study aimed to assess shared familial risk between IS and MI in a large, population-wide cohort study., Methods: Study participants free of IS and MI and their affected siblings were extracted from the Swedish Hospital Discharge and Cause of Death Registers between 1987 and 2007, forming an exposed sib-pair. They were matched by birth year of both siblings and calendar period to up to five unexposed sib-pairs. Stratified Cox regression analyses were used to assess familial risk of MI and IS in those exposed to having a sibling with IS (n = 31,659) and MI (n = 62,766), respectively, compared to unexposed (n = 143,728 and 265,974)., Results: The overall risk of MI when exposed to having a sibling with IS was statistically significantly increased (RR, 1.44; 95% CI, 1.34-1.55, p < 0.001) to a similar extent as risk of IS when exposed to having a sibling with MI (RR, 1.41; 95% CI, 1.32-1.50, p < 0.001). The familial risks were similar in full siblings for both groups (RR for MI, 1.46; 95% CI, 1.35-1.58, p < 0.001; and RR for IS, 1.40; 95% CI, 1.30-1.40, p < 0.001) and half siblings (RR for MI, 1.29; 95% CI, 1.05-1.59, p < 0.001; and RR for IS, 1.38; 95% CI, 1.16-1.65, p < 0.001)., Conclusion: This large, population-wide study indicates that there is considerable overlap of familial risk between IS and MI.

Objectives: Firefighters are potentially exposed to a wide range of known and suspected carcinogens through their work. The objectives of this study were to examine the patterns of cancer among Nordic firefighters, and to compare them with the results from previous studies., Methods: Data for this study were drawn from a linkage between the census data for 15 million people from the five Nordic countries and their cancer registries for the period 1961-2005. SIR analyses were conducted with the cancer incidence rates for the entire national study populations used as reference rates., Results: A total of 16 422 male firefighters were included in the final cohort. A moderate excess risk was seen for all cancer sites combined, (SIR=1.06, 95% CI 1.02 to 1.11). There were statistically significant excesses in the age category of 30-49 years in prostate cancer (SIR=2.59, 95% CI 1.34 to 4.52) and skin melanoma (SIR=1.62, 95% CI 1.14 to 2.23), while there was almost no excess in the older ages. By contrast, an increased risk, mainly in ages of 70 years and higher, was observed for non-melanoma skin cancer (SIR=1.40, 95% CI 1.10 to 1.76), multiple myeloma (SIR=1.69, 95% CI 1.08 to 2.51), adenocarcinoma of the lung (SIR=1.90, 95% CI 1.34 to 2.62), and mesothelioma (SIR=2.59, 95% CI 1.24 to 4.77). By contrast with earlier studies, the incidence of testicular cancer was decreased (SIR=0.51, 95% CI 0.23 to 0.98)., Conclusions: Some of these associations have been observed previously, and potential exposure to polycyclic aromatic hydrocarbons, asbestos and shift work involving disruption of circadian rhythms may partly explain these results.

Objectives: In view of declining screening uptake in young women, this review aims to summarise the available evidence relating to interventions designed to increase cervical screening uptake amongst women aged ≤ 35 years., Methods: Electronic databases were searched and further articles located by manual searches. Study designs employing a valid comparison group and including women aged ≤ 35 years published through 2012 were considered. Data was extracted on the uptake from either screening programme statistics or as reported by the study subjects. A narrative synthesis was undertaken for each category of interventions identified., Results: Ninety-two records were screened with 36 articles retrieved for further assessment. Four studies met the inclusion criteria, two of which evaluated more than one intervention. One of the studies evaluated the use of a modified invitation letter and reported no significant increase in uptake compared to a standard invitation. Three studies investigated the use of a reminder letter, with two reporting a positive effect on screening uptake in women aged 24-34. Three studies were included which supported the use of physician and telephone reminders. One study on HPV self-sampling reported a positive effect when compared with a reminder letter., Conclusions: There is a lack of randomised controlled trials designed to specifically address falling cervical screening uptake in amongst young women. Cervical screening programmes need to look beyond the use of invitation/reminders letters in this group of women to develop interventions which attempt to overcome as many barriers to uptake as possible.

Importance: Determining vaccine dose-level protection is essential to minimize program costs and increase mass vaccination program feasibility. Currently, a 3-dose vaccination schedule is recommended for both the quadrivalent and bivalent human papillomavirus (HPV) vaccines. Although the primary goal of HPV vaccination programs is to prevent cervical cancer, condyloma related to HPV types 6 and 11 is also prevented with the quadrivalent vaccine and represents the earliest measurable preventable disease outcome for the HPV vaccine., Objective: To examine the association between quadrivalent HPV vaccination and first occurrence of condyloma in relation to vaccine dose in a population-based setting., Design, Setting, and Participants: An open cohort of all females aged 10 to 24 years living in Sweden (n = 1,045,165) was followed up between 2006 and 2010 for HPV vaccination and first occurrence of condyloma using the Swedish nationwide population-based health data registers., Main Outcomes and Measures: Incidence rate ratios (IRRs) and incidence rate differences (IRDs) of condyloma were estimated using Poisson regression with vaccine dose as a time-dependent exposure, adjusting for attained age and parental education, and stratified on age at first vaccination. To account for prevalent infections, models included a buffer period of delayed case counting., Results: A total of 20,383 incident cases of condyloma were identified during follow-up, including 322 cases after receipt of at least 1 dose of the vaccine. For individuals aged 10 to 16 years at first vaccination, receipt of 3 doses was associated with an IRR of 0.18 (95% CI, 0.15-0.22) for condyloma, whereas receipt of 2 doses was associated with an IRR of 0.29 (95% CI, 0.21-0.40). One dose was associated with an IRR of 0.31 (95% CI, 0.20-0.49), which corresponds to an IRD of 384 cases (95% CI, 305-464) per 100,000 person-years, compared with no vaccination. The corresponding IRDs for 2 doses were 400 cases (95% CI, 346-454) and for 3 doses, 459 cases (95% CI, 437-482). The number of prevented cases between 3 and 2 doses was 59 (95% CI, 2-117) per 100,000 person-years., Conclusions and Relevance: Although maximum reduction in condyloma risk was seen after receipt of 3 doses of quadrivalent HPV vaccine, receipt of 2 vaccine doses was also associated with a considerable reduction in condyloma risk. The implications of these findings for the relationship between number of vaccine doses and cervical cancer risk require further investigation.

Objective: To determine factors influencing long term risks for acquiring or dying from invasive cervical or vaginal cancer in women previously treated for cervical intraepithelial neoplasia grade 3 (CIN3)., Design: Population based cohort study conducted in 1958-2008, followed up until 2009 in the Swedish Cancer Registry and Swedish Cause of Death Register, linked to the Swedish Population Register. Standardised incidence and mortality ratios were calculated for the risk of acquiring or dying from vaginal or cervical cancer, with the general female population in Sweden as reference. Relative risks in multivariable regression models were also calculated, adjusting for follow-up duration, treatment period, and age at CIN3 treatment or attained age., Setting: Entire female population of Sweden., Participants: 150,883 women in Sweden diagnosed and treated with CIN3 and followed up for invasive cervical or vaginal cancer, and related mortality. The cohort comprised 3,148,222 woman years., Main Outcome Measures: Standardised incidence and mortality ratios, stratified by period for treatment. Relative standardised incidence ratios and standardised mortality ratios for age at acquiring or dying from cervical or vaginal cancer (attained age), adjusted for preset variables., Results: Women previously diagnosed with CIN3 had an increased risk of dying from invasive cervical or vaginal cancer, compared with the general female population (standardised mortality ratio 2.35, 95% confidence interval 2.11 to 2.61). After age 60 years, these women had an accelerated increased risk of acquiring invasive cancer; a similar steep increase in mortality risk was seen after age 70. Regression analyses indicated that the increase in risk over time is highly attributable to ageing., Conclusions: Women previously treated for CIN3 are at increased risk of developing and dying from cervical or vaginal cancer, compared with the general female population. The risk accelerates above age 60 years, suggesting a need for lifelong surveillance of these women.

Objectives: A cluster of 11 cases of cholangiocarcinoma (CC) was observed in a small Japanese printing firm. To elucidate whether the identified cluster is indicative of an elevated risk of CC among workers in the printing industry at large, we explored the risk of cancer of the liver and CC among individuals employed in the printing industry in a large cohort set-up in four Nordic countries (Finland, Iceland, Norway and Sweden) over a period of 45 years., Methods: The cohort was set-up by linking occupational information from censuses to national cancer registry data utilising personal identity codes in use in all Nordic countries. We calculated standardised incidence ratios (SIRs) for men and women working in the printing industry, and stratified by occupational category (typographers, printers, lithographers, bookbinders)., Results: Among men, we observed elevated SIRs for cancer of the liver (1.35, 95% CI 1.14 to 1.60; 142 cases), specifically intrahepatic CC (2.34, 95% CI 1.45 to 3.57; 21 cases). SIRs for liver cancer were especially elevated among printers and lithographers, and SIRs for intrahepatic CC among typographers and printers. SIRs for extrahepatic CC were not elevated. SIRs for women followed a similar pattern but the number of cases was low., Conclusions: Our study supports the notion that the finding of excess CC risk among workers in a small Japanese printing firm possibly extends beyond this specific firm and country. Further studies should focus on the specific exposures that occur in the printing industry.

Objectives: This study explored how adult social class and social mobility between parental and own adult social class is related to psychiatric disorder., Material and Methods: In this prospective cohort study, over 1 million employed Swedes born in 1949-1959 were included. Information on parental class (1960) and own mid-life social class (1980 and 1990) was retrieved from the censuses and categorised as High Non-manual, Low Non-manual, High Manual, Low Manual and Self-employed. After identifying adult class, individuals were followed for psychiatric disorder by first admission of schizophrenia, alcoholism and drug dependency, affective psychosis and neurosis or personality disorder (N=24,659) from the Swedish Patient Register. We used Poisson regression analysis to estimate first admission rates of psychiatric disorder per 100,000 person-years and relative risks (RR) by adult social class (treated as a time-varying covariate). The RRs of psychiatric disorder among the Non-manual and Manual classes were also estimated by magnitude of social mobility., Results: The rate of psychiatric disorder was significantly higher among individuals belonging to the Low manual class as compared with the High Non-manual class. Compared to High Non-manual class, the risk for psychiatric disorder ranged from 2.07 (Low Manual class) to 1.38 (Low Non-manual class). Parental class had a minor impact on these estimates. Among the Non-manual and Manual classes, downward mobility was associated with increased risk and upward mobility with decreased risk of psychiatric disorder. In addition, downward mobility was inversely associated with the magnitude of social mobility, independent of parental class., Conclusions: Independently of parental social class, the risk of psychiatric disorder increases with increased downward social mobility and decreases with increased upward mobility.

Objective: To assess the risk of serious adverse events after vaccination of adolescent girls with quadrivalent human papillomavirus (qHPV) vaccine., Design: Register based cohort study., Setting: Denmark and Sweden, October 2006 to December 2010., Participants: 997,585 girls aged 10-17, among whom 296,826 received a total of 696,420 qHPV vaccine doses., Main Outcome Measures: Incident hospital diagnosed autoimmune, neurological, and venous thromboembolic events (53 different outcomes) up to 180 days after each qHPV vaccine dose. Only events with at least five vaccine exposed cases were considered for further assessment. Rate ratios adjusted for age, country, calendar year, and parental country of birth, education, and socioeconomic status were estimated, comparing vaccinated and unvaccinated person time. For outcomes where the rate ratio was significantly increased, we regarded three criteria as signal strengthening: analysis based on 20 or more vaccine exposed cases (reliability), rate ratio 3.0 or more (strength), and significantly increased rate ratio in country specific analyses (consistency). We additionally assessed clustering of events in time and estimated rate ratios for a risk period that started on day 181., Results: Among the 53 outcomes, at least five vaccine exposed cases occurred in 29 and these were analysed further. Whereas the rate ratios for 20 of 23 autoimmune events were not significantly increased, exposure to qHPV vaccine was significantly associated with Behcet's syndrome, Raynaud's disease, and type 1 diabetes. Each of these three outcomes fulfilled only one of three predefined signal strengthening criteria. Furthermore, the pattern of distribution in time after vaccination was random for all three and the rate ratios for these outcomes in the period from day 181 after vaccination were similar to the rate ratios in the primary risk period. The rate ratios for five neurological events were not significantly increased and there were inverse associations with epilepsy (rate ratio 0.66, 95% confidence interval 0.54 to 0.80) and paralysis (0.56, 0.35 to 0.90). There was no association between exposure to qHPV vaccine and venous thromboembolism (0.86, 0.55 to 1.36)., Conclusions: This large cohort study found no evidence supporting associations between exposure to qHPV vaccine and autoimmune, neurological, and venous thromboembolic adverse events. Although associations for three autoimmune events were initially observed, on further assessment these were weak and not temporally related to vaccine exposure. Furthermore, the findings need to be interpreted considering the multiple outcomes assessed.

Objectives: Trichloroethylene (TCE) and Perchloroethylene (PER) are two chlorinated solvents that are applied widely as degreasers of metal parts, and in dry cleaning and other applications. In 2012, the International Agency for Research on Cancer classified TCE as carcinogenic to humans and PER as probably carcinogenic to humans. We explored exposure-response relations for TCE and PER and non-Hodgkin's lymphoma (NHL), multiple myeloma (MM), and cancers of the kidney and liver in the Nordic Occupational Cancer cohort., Methods: The cohort was set up by linking occupational information from censuses to national cancer registry data using personal identity codes in use in all Nordic countries. Country, time period, and job-specific exposure estimates were generated for TCE, PER and potentially confounding occupational exposures with a job-exposure matrix. A conditional logistic regression was conducted for exposure groups as well as for continuous cumulative exposure., Results: HRs for liver cancer, NHL and MM but not kidney cancer were slightly elevated in groups with high exposure to PER (compared to occupationally unexposed subjects). HRs for liver cancer and NHL also increased with increasing continuous exposure to PER. We did not observe evidence for an association between exposure to TCE and NHL, MM or liver and kidney cancer., Conclusions: Although this study was subject to limitations related to the low prevalence of exposure to PER and TCE in the Nordic population and a limited exposure assessment strategy, we observed some evidence indicative of an excess risk of cancer of the liver and NHL in subjects exposed to PER.

Background: Incidence of condyloma, or genital warts (GW), is the earliest possible disease outcome to measure when assessing the effectiveness of human papillomavirus (HPV) vaccination strategies. Efficacy trials that follow prespecified inclusion and exclusion criteria may not be fully generalizable to real-life HPV vaccination programs, which target a broader segment of the population. We assessed GW incidence after on-demand vaccination with quadrivalent HPV vaccine using individual-level data from the entire Swedish population., Methods: An open cohort of girls and women aged 10 to 44 years living in Sweden between 2006 and 2010 (N > 2.2 million) was linked to multiple population registers to identify incident GW in relation to HPV vaccination. For vaccine effectiveness, incidence rate ratios of GW were estimated using time-to-event analyses with adjustment for attained age and parental education level, stratifying on age at first vaccination., Results: A total of 124 000 girls and women were vaccinated between 2006 and 2010. Girls and women with at least one university-educated parent were 15 times more likely to be vaccinated before age 20 years than girls and women whose parents did not complete high school (relative risk ratio = 15.45, 95% confidence interval [CI] = 14.65 to 16.30). Among those aged older than 20 years, GW rates declined among the unvaccinated, suggesting that HPV vaccines were preferentially used by women at high risk of GW. Vaccination effectiveness was 76% (95% CI = 73% to 79%) among those who received three doses of the vaccine with their first dose before age 20 years. Vaccine effectiveness was highest in girls vaccinated before age 14 years (effectiveness = 93%, 95% CI = 73% to 98%)., Conclusions: Young age at first vaccination is imperative for maximizing quadrivalent HPV vaccine effectiveness.

Objective: To assess the risk of epileptic seizures in people with and without epilepsy after vaccination with a monovalent AS03 adjuvanted pandemic A/H1N1 influenza vaccine (Pandemrix; Glaxo SmithKline, Sweden)., Design: Register based self controlled case series., Setting: Three Swedish counties (source population 750,000)., Participants: 373,398 people (age 0-106, median 41.2) who were vaccinated. Vaccinated people with epileptic seizures, diagnosed as inpatients or outpatients, at any time from 90 days before until 90 days after any dose of vaccine., Main Outcome Measures: Endpoints were admission to hospital or outpatient hospital care with epileptic seizures as the main diagnosis. The effect estimate of relative incidence was calculated as the incidence of epileptic seizures in period after exposure relative to the incidence of epileptic seizures in two control periods, one before and one after vaccination., Results: 859 people experienced epileptic seizures during the study period. There was no increased risk of seizures in people with previously diagnosed epilepsy (relative incidence 1.01, 95% confidence interval 0.74 to 1.39) and a non-significant decrease in risk for people without epilepsy (0.67, 0.27 to 1.65) during the day 1-7 risk period (where day 1 is the day of vaccination). In a second risk period (day 8-30), there was a non-significant increased risk of seizures in people without epilepsy (1.11, 0.73 to 1.70) but no increase in risk for those with epilepsy (1.00, 0.83 to 1.21)., Conclusions: This study found no evidence of an increase in risk of presentation to hospital with epileptic seizures after vaccination with a monovalent AS03 adjuvanted pandemic H1N1 influenza vaccine.

The negative impact of low social class on cardiovascular disease (CVD) and mortality has been consistently documented. However, less scientific consistency exists in terms of whether a unique health effect of social mobility from childhood to adulthood prevails. This study explored how childhood and adult social class and the transition between them (social mobility), are related to premature CVD mortality when familial aggregation of CVD among siblings is also considered. The study includes nearly 1.9 million Swedish residents born 1939-1959 distributed over 1,044,725 families, of whom 14,667 died prematurely from CVD in 1990-2003. Information on parental class (1960) and own mid-life occupational class (1990) was retrieved from the respective censuses. Odds ratios for premature CVD mortality according to trajectory-specific social mobility, along with pairwise mean odds ratios for sibling resemblance of premature CVD mortality, were calculated by means of alternating logistic regression. This model calculates the remaining dependency of CVD mortality within sibships after accounting for available risk factors (like parental and adult social class) in the population mean model. Results showed that premature CVD mortality was associated with both parental and own adult social class. A clear tendency for the downwardly mobile to have increased, and for the upwardly mobile to experience a decreased risk of premature CVD mortality was found, as well as a corresponding unique effect of social mobility per se among the manual and non-manual classes. This effect was verified for men, but not for women, when they were analysed separately. The pairwise mean odds ratios for premature CVD mortality among full siblings were 1.78 (95% CI: 1.52-2.08), and were independent of parental CVD mortality and parental or adult occupational class., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background: More than 90% of genital warts (GW) cases are caused by human papillomavirus (HPV) types 6 and 11. The introduction of HPV vaccines necessitates the estimation of the population-based incidence of GW immediately before and after vaccination uptake., Methods: Incidence proportions were calculated using the entire population aged 10–44 years living in Sweden during 2006–2010. The Prescribed Drug Register and the National Patient Register were used to define GW episodes. Time trends were estimated using Poisson regression., Results: In 2010, age-stratified incidence proportions of GW were highest for 20-year-old women (956 cases/100 000), while the incidence proportion among males was greatest at the slightly older age of 24 years (1137 cases/100 000). Crude rates were marginally higher among males than among females during 2006–2007 and appeared to later diverge. Between 2008 and 2010, the overall incidence appeared to increase among males, and the incidence among females declined. Females aged 17 and 18 years had a >25% decline in GW rates between 2006 and 2010, with significant decreases through the age of 25 years., Conclusions: This study provides a reasonable estimation of the incidence of GW in the Swedish population by use of register data, with results comparable to those from previous smaller studies. There was a downward trend of GW incidence among younger females between 2006 and 2010.

Background: Low socioeconomic status (SES) has been linked to increased risk of hypertension, a known risk factor for cardiovascular disease. How the risk is altered by intergenerational social mobility is not well known. The aim of this study is to investigate parental SES, adult SES and the intergenerational social mobility in relation to hypertension risk., Methods: By using data from the Swedish Twin Registry, the authors obtained information about both parental and adult SES and hypertension in 12 030 individuals born from 1926 to 1958. Generalised estimating equations were used to estimate ORs with 95% CIs., Results: Low parental SES was associated with increased odds of hypertension (OR 1.42, 95% CI 1.14 to 1.76). Low SES in adulthood was associated with increased odds for women but not for men (OR 1.40, 95% CI 1.15 to 1.70 and OR 1.01, 95% CI 0.83 to 1.24, respectively). Compared with the stable low social status group, the upward mobile group had lower odds of hypertension (OR 0.82, 95% CI 0.70 to 0.97). Compared with the stable high social status group, the results for the downward mobile group indicated an increased risk. A co-twin case-control analysis indicated that the results were independent of familial factors., Conclusions: These findings suggest that the risk of hypertension associated with low parental social status can be modified by social status later in life. Possibly, this could be targeted by public health or political interventions. As parental social status has an impact on later health, such interventions should be introduced early.

Background: Risk-taking behaviours such as early initiation of smoking, alcohol drinking and sexual activity often cluster within individuals and could be characteristics of adolescents who in general are risk takers. In the present study, using a large population-based sample of 64 659 women aged 18-45 years in four Nordic countries, we investigate whether young age at first sexual intercourse is associated with subsequent risk-taking behaviours., Methods: We examined the association between young age at first sexual intercourse (age ≤14 years) and subsequent risk-taking behaviours by using multivariate logistic regression by which odds ratios (ORs) and the corresponding 95% confidence intervals (95% CIs) were estimated., Results: The OR of reporting more than 10 lifetime sexual partners was almost four times higher among women who reported a young age at first intercourse (OR = 3.79; 95% CI: 3.60-4.00) in comparison with women >14 years at first intercourse. Furthermore, women who were young at first intercourse were more likely to report two or more recent partners (OR = 1.67; 95% CI: 1.54-1.82) and to have a history of STIs (OR = 2.03; 95% CI: 1.93-2.13). In addition, young age at first intercourse was associated with current smoking (OR = 2.31; 95% CI: 2.20-2.43) and binge drinking (OR = 1.36; 95% CI: 1.28-1.44). All ORs were adjusted for age, years of education and country of residence., Conclusion: Young age at first intercourse is associated with subsequent risk-taking behaviours. Our study emphasizes the importance of targeting prevention efforts towards the complexity of risk-taking behaviours.

Background: Previous studies on familial risk of ischemic stroke have supported genetic influence on the disease incidence. This study aimed to characterize these familial effects in a nationwide population-based study by taking into account sibling relations, sex of siblings, and age of onset, with respect to ischemic stroke incidence., Methods and Results: Incident ischemic stroke cases identified from the Swedish Hospital Discharge and Cause of Death Registers between 1987 and 2007 were linked to their stroke-free siblings (study participants), forming an exposed sib-pair. Each exposed sib-pair was matched up to 5 unexposed sib-pairs from the Multi-Generation Registry by birth and calendar years. Incident ischemic stroke risk was assessed using hazard estimates obtained from stratified Cox regression analyses. A total of 30 735 exposed and 152 391 unexposed study participants were included in the analyses. The overall risk of incident ischemic stroke when exposed was significantly increased (relative risk, 1.61; 95% confidence interval, 1.48-1.75; P<0.001). Familial risk was higher in full (relative risk, 1.64; 95% confidence interval, 1.50-1.81; P<0.001) than in half (relative risk, 1.41; 95% confidence interval, 1.10-1.82; P=0.007) siblings. Familial risk of early ischemic stroke almost doubled when exposed to early ischemic stroke (relative risk, 1.94; 95% confidence interval, 1.41-2.67; P<0.001)., Conclusions: There was a 60% increased risk for ischemic stroke in individuals having a sibling with prior stroke. The familial effect was even higher for full-sibling relations. Familial effects were observed in both male and female individuals, and no differential effects depending on the sex of either of the siblings were found.

Objective: To determine whether detection of invasive cervical cancer by screening results in better prognosis or merely increases the lead time until death., Design: Nationwide population based cohort study., Setting: Sweden., Participants: All 1230 women with cervical cancer diagnosed during 1999-2001 in Sweden prospectively followed up for an average of 8.5 years., Main Outcome Measures: Cure proportions and five year relative survival ratios, stratified by screening history, mode of detection, age, histopathological type, and FIGO (International Federation of Gynecology and Obstetrics) stage., Results: In the screening ages, the cure proportion for women with screen detected invasive cancer was 92% (95% confidence interval 75% to 98%) and for symptomatic women was 66% (62% to 70%), a statistically significant difference in cure of 26% (16% to 36%). Among symptomatic women, the cure proportion was significantly higher for those who had been screened according to recommendations (interval cancers) than among those overdue for screening: difference in cure 14% (95% confidence interval 6% to 23%). Cure proportions were similar for all histopathological types except small cell carcinomas and were closely related to FIGO stage. A significantly higher cure proportion for screen detected cancers remained after adjustment for stage at diagnosis (difference 15%, 7% to 22%)., Conclusions: Screening is associated with improved cure of cervical cancer. Confounding cannot be ruled out, but the effect was not attributable to lead time bias and was larger than what is reflected by down-staging. Evaluations of screening programmes should consider the assessment of cure proportions.

Cervical cancer is one of the most common cancers among women worldwide, although cervical screening has reduced the incidence in many high-income countries. Low screening uptake among immigrant women may reflect differences in risk of cervical cancer. We investigated the degree of participation in cervical screening among immigrant and Swedish-born women and their concurrent risk of cervical cancer based on individual information on Pap smears taken both from organized and opportunistic screening. Mean degree of participation in cervical screening was estimated for women between 23 and 60 years from 1993 to 2005, stratified by birth region and age at migration. In Poisson regression models, we estimated relative risks (RRs), incidence rates and incidence rate ratios of cervical cancer for women adhering or not to the cervical screening program. We also assessed effect of adherence to screening on the risk of cervical cancer among immigrant groups compared to Swedish-born women. The degree of participation was 62% and 49% among Swedish-born and immigrant women, respectively, with large variations between immigrant groups. Participation was lowest among those immigrating at older ages. Swedish-born and immigrant women who where nonadherent to the cervical screening program had a fivefold excess risk of cervical cancer compared to adherent women. After adjustment for screening adherence, excess RRs of cervical cancer were statistically significant only for women from Norway and the Baltic States. Participation to screening is lower among immigrant than Swedish-born women, and adherence to the recommended screening intervals strongly prevents cervical cancer., (Copyright © 2011 UICC.)

Purpose: To assess awareness and knowledge of human papillomavirus (HPV) in the adult Swedish population., Methods: A cross-sectional study among young adults aged 18-30 years and the parents of children aged 12-15 years was conducted in 2007 to collect information on awareness and knowledge of HPV. Correlates of HPV knowledge were investigated., Results: Awareness of cervical cancer and condyloma were high but awareness of HPV was low. Many participants were uncertain or did not know about the causal relation between HPV and condyloma, and cancers other than cervical cancer. Among parents, gender, age, country of origin, and education were the most important correlates of HPV knowledge. Among young adults, these factors were gender, income, and education., Conclusions: HPV education campaigns should particularly target young men and those with low education. Educational messages should clarify the risk of HPV, and the causal relationship between HPV and condyloma, and other cancers., (Copyright © 2012 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

Previously published studies on the risk of cancer among male priests have been based on cancer mortality with the exception of one case-control study. The aim of this study was to present estimates of cancer incidence among Nordic male priests. The study cohort for our analyses consisted of 6.5 million men aged 30-64 years old who had participated in any computerised population census in four Nordic countries in 1990 or earlier. Follow-up was done by drawing linkages with the national population and cancer registries. 13,491 priests were identified by their job title codes. We estimated the standardised incidence ratio (SIR) and 95% confidence intervals (95% CI) for the priests using the male population as a reference. Priests had a lower cancer incidence than the general population (overall SIR 0.85, 95% CI: 0.82-0.88). The majority of smoking- and alcohol-related cancers were associated with decreased SIR estimates. Increased risks were observed for skin melanoma (SIR 1.34, 95% CI: 1.11-1.62), acute myeloid leukemia (SIR 1.75, 95% CI: 1.20-2.47) and thyroid cancer (SIR 1.86, 95% CI: 1.22-2.73). This is the first cohort study regarding the incidence of cancer among priests. The lower incidence of smoking and alcohol-related cancers among Nordic male priests can be explained by their lower exposure to cigarettes and alcohol when compared to the general population. A greater risk of melanoma is typical of highly-educated people, but it is unclear why priests should have an increased risk of acute myeloid leukemia or thyroid cancer.

A substantial proportion of women with cervical cancer that have participated in cervical screening have a history of an abnormal cytology result. Our objective was to assess the impact of histological investigation and treatment of women with abnormal cytology on the subsequent risk of invasive cervical cancer. All invasive cervical cancer cases in Sweden 1999-2001 and five population-based control women per case were investigated. Clinical investigations and treatment were analysed in case women (N = 143) and control women (N = 176) below 67 with abnormal cytology results 0.5-6.5 years before the cases' diagnosis. Cervical cancer risk in relation to investigation [histology or not, punch biopsy, cervical curettage or cone/large loop excision of the transformation zone (LLETZ)], and treatment (treatment or not, excisional or ablative) was estimated as odds ratios (ORs) using logistic regression. Absence of histological assessment was associated with increased cancer risk, both after low-grade [OR 2.37; 95% confidence intervals (CI): 1.27-4.43] and high-grade squamous atypia (8.26; 2.37-28.8). Among women with histology, absence of treatment was associated with increased cancer risk (3.68; 1.53-8.84), also when biopsy showed low-grade atypia or normal findings (3.57; 1.18-10.8). Ablative therapy associated with increased risk compared with excisional (3.82; 1.01-14.4), and laser conisation associated with decreased risk compared with LLETZ (0.06; 0.01-0.36). In conclusion, low-grade as well as high-grade squamous atypical cytology results may warrant histological investigation, treatment reduced cancer risk even when histology was negative or showed low-grade atypia indicating a need for improvements in the diagnosis of high-grade lesions, and laser conisation was the most effective treatment., (Copyright © 2010 UICC.)

Background: The aim of this study was to assess the prevalence of women reporting ever having genital chlamydia, genital herpes, Trichomonas vaginalis, and gonorrhea, and to identify factors associated with each of these sexually transmitted infections (STIs)., Methods: The study was based on a large cross-sectional survey conducted in 2004-2005 among randomly sampled women (18-45 years) from the computerized population registries in Denmark, Iceland, Norway, and Sweden. A total of 69,567 women were included in the study., Results: The overall prevalence in Denmark, Iceland, Norway, and Sweden was 1.5% for reporting ever having had Trichomonas vaginalis, 1.9% for gonorrhea, 4.8% for genital herpes, and 17.0% for genital chlamydia. The prevalence of each of these STIs varied with birth cohort and country. In addition, they were strongly associated with lifetime number of partners and having a previous diagnosis of another sexually transmitted infection. Moreover, a diagnosis of genital chlamydia or gonorrhea was associated with early age at first intercourse and smoking initiation. Finally, reporting genital chlamydia was associated with early age at drinking initiation, and ever use of hormonal contraceptives and condoms., Conclusion: Genital chlamydia occurs frequently among women in the Nordic countries. Risk-taking behavior, particularly sexual behavior, is strongly associated with STIs, which suggest that further information is needed about STIs and their consequences, targeting high-risk groups. There is also a need for continued monitoring of STIs in order to follow the prevalence and to gain further knowledge about risk factors.

Objective: To study excess mortality, causes of death, and co-morbidity in patients with eating disorder (ED), treated in a Swedish specialist facility., Method: A retrospective cohort study of 201 patients with ED followed from 1974 to year 2001 in the Swedish Causes of Death Register (SCODR). Standardized mortality ratio (SMR) was calculated with respect to the Swedish population, by gender, age, and calendar time., Results: In the complete follow-up of 201 patients, 23 had died. At a mean follow-up of 14.3 years the overall SMR was 10. Patients with body mass index (BMI) over 11.5 had an average SMR of about 7 and for those with BMI lower than 11.5 had SMR above 30. Six patients died from AN/starvation, nine due to suicide, and eight from other causes., Discussion: SMR in anorexia nervosa (AN) is high but not in bulimia nervosa. A risk stratification of AN, based on BMI is suggested., (Copyright © 2010 Wiley Periodicals, Inc.)

We studied age at diagnosis and disease progression of cystic fibrosis (CF) patients with a new study design, using data of 119 patients extracted from Stockholm CF Centre registry. Risk factors for overall morbidity and for lung, liver and nutritional morbidity were investigated separately using time to event methodology (Kaplan-Meier curves, proportional hazards regression). The patients were followed from: (i) healthy at diagnosis to morbidity, (ii) diagnosis with symptoms of morbidity to being free of morbidity, and (iii) free of morbidity to relapse of morbidity. Median age at diagnosis was 5.0 months. Of the patients with overall morbidity at diagnosis 50% became free of morbidity after 4.8 years; however, the patients above the age of 24 months at diagnosis had a reduced chance of becoming free of morbidity (crude hazard ratio 0.14 [95 % confidence interval 0.04, 0.45]) compared with those with diagnosis between the ages of 2 and 12 months (P<0.01). Of the healthy at diagnosis, 50% experienced overall morbidity after 1.4 years. They had a slow decline to the endpoint of the specific morbidities; 50% experienced lung morbidity after 3.4 years and liver morbidity after 4.8 years, while 50% never reached nutritional morbidity during the 10 years follow-up. We conclude that there was a disadvantage for the CF patients diagnosed after the age of 24 months with symptoms of overall morbidity at diagnosis in an area without newborn screening., (© 2011 Blackwell Publishing Ltd.)

Knowledge of the prevalence of different human papillomavirus (HPV) types in young girls is important for the early detection of changes in HPV prevalence, e.g. due to HPV vaccines. The purpose of this study was to obtain information on the prevalence of 24 different genital HPV types in a group of sexually active young women (aged 15-23 y) attending a major youth healthcare centre in Stockholm, before the introduction of public HPV vaccination of young women in the autumn of 2010. A total of 615 women were analyzed for 24 different, mainly high-risk HPV (HR-HPV) types using multiplex polymerase chain reaction and Luminex technology. A high HPV prevalence in this cohort was demonstrated, particularly with regard to HPV16, but also to all included HR-HPV types. Of the 544 successfully analyzed samples from non-vaccinated individuals, 70% were positive for the HPV types assayed for, and 62% were positive for HR-HPV types. Over a third (34.7%) of the women were infected with HPV16, and a high frequency of infections with HR-HPV types 51 (10.7%), 18 (10.1%), 52 (9.9%) and 73 (9.4%) was also observed. At least 9 different non-vaccine HR-HPV types were present with a prevalence of >6% in this selected group of young women.

Introduction: To better understand trends in sexually transmitted infection (STI) prevention, specifically low prevalence of condom use with temporary partners, the aim of this study was to examine factors associated with condom use and perceptions of STI risk amongst individuals at risk, with the underlying assumption that STI risk perceptions and STI prevention behaviors are correlated., Methods: A national population-based survey on human papillomavirus (HPV) and sexual habits of young adults aged 18-30 was conducted in Sweden in 2007, with 1712 men and 8855 women participating. Regression analyses stratified by gender were performed to measure condom use with temporary partners and STI risk perception., Results: Men's condom use was not associated with STI risk perception while women's was. Awareness of and disease severity perceptions were not associated with either condom use or risk perception though education level correlated with condom use. Women's young age at sexual debut was associated with a higher risk of non-condom use later in life (OR 1.95 95% CI: 1.46-2.60). Women with immigrant mothers were less likely to report seldom/never use of condoms with temporary partners compared to women with Swedish-born mothers (OR 0.53 95% CI: 0.37-0.77). Correlates to STI risk perception differ substantially between sexes. Number of reported temporary partners was the only factor associated for both men and women with condom use and STI risk perception., Conclusions: Public health interventions advocating condom use with new partners could consider employing tactics besides those which primarily aim to increase knowledge or self-perceived risk if they are to be more effective in STI reduction. Gender-specific prevention strategies could be effective considering the differences found in this study.

It is unknown whether severe emotional stress due to loss of a child influences the risk of cancers susceptible to immune modulation such as infection-related cancers. We conducted a historic cohort study in 1990 to 2004 on the basis of the Swedish Multi-Generation Register including 4,687,073 parents. Death of a child was identified through the Causes of Death Register. Poisson regression was used to derive the relative risks (RR) and 95% confidence intervals (CI) of infection-related cancers, comparing the incidence rates of parents who lost a child with those who never lost a child. A total of 101,306 parents (2%) had lost a child during follow-up, among whom 1,608 subsequently developed infection-related cancers. After adjustment for age, sex, calendar year, educational level, and civil status, the overall RR of 14 cancers studied was 1.07 (95% CI: 1.02-1.12). Parents who lost a child were particularly at a higher risk for cancers potentially associated with human papilloma virus (HPV) infection such as cervical cancer (RR: 1.46; 95% CI: 1.17-1.80). Higher RRs for most cancers were obtained within 5 years after child loss and excess risk for liver and stomach cancers was confined to that period. No association was observed for lymphoma and nonmelanoma skin cancer at any time point after child loss. Although potential confounding by unmeasured factors cannot be ruled out, our findings lend support to the hypothesis that severe life stressors, such as child loss, may raise the risk for several, chiefly HPV-related, cancers., (© 2011 AACR.)

Acceptability of human papillomavirus (HPV) vaccination seems to be high in the Western world but fewer data are available for men than for women. There are also concerns that HPV vaccination might lead young people to change their healthcare-related behaviours. We investigated these issues in a population-based survey performed in Sweden during January-May, 2007, just after HPV vaccination had been licensed. A total of 10567 men and women aged 18 to 30 years participated. The intention to accept HPV vaccination among these young adults was relatively high but could likely be improved with higher awareness of HPV-related diseases as well as of the safety and efficacy of vaccines in general. Also, the cost of the vaccine needs to be affordable. Even though few young adults stated their healthcare-related behaviours would change after HPV vaccination, a significant number were uncertain, suggesting a need for continued educational efforts when HPV-vaccinating this group., (Copyright © 2010 Elsevier Ltd. All rights reserved.)