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Objective To investigate the separate and combined effects of overall heavy physical workload (PWL) and low decision authority on all-cause disability pension (DP) or musculoskeletal DP. Methods This study uses a sample of 1,804,242 Swedish workers aged 44–63 at the 2009 baseline. Job Exposure Matrices (JEMs) estimated exposure to PWL and decision authority. Mean JEM values were linked to occupational codes, then split into tertiles and combined. DP cases were taken from register data from 2010 to 2019. Cox regression models estimated sex-specific Hazard Ratios (HR) with 95% confidence intervals (95% CI). The Synergy Index (SI) estimated interaction effects. Results Heavy physical workload and low decision authority were associated with an increased risk of DP. Workers with combined exposure to heavy PWL and low decision authority often had greater risks of all-cause DP or musculoskeletal DP than when adding the effects of the single exposures. The results for the SI were above 1 for all-cause DP (men: SI 1.35 95%CI 1.18–1.55, women: SI 1.19 95%CI 1.05–1.35) and musculoskeletal disorder DP (men: SI 1.35 95%CI 1.08–1.69, women: 1.13 95%CI 0.85–1.49). After adjustment, the estimates for SI remained above 1 but were not statistically significant. Conclusion Heavy physical workload and low decision authority were separately associated with DP. The combination of heavy PWL and low decision authority was often associated with higher risks of DP than would be expected from adding the effects of the single exposures. Increasing decision authority among workers with heavy PWL could help reduce the risk of DP.

Objectives The aim of the study was to examine the associations between heavy physical workload among middle-aged and older workers and disability pension due to any diagnosis, as well as musculoskeletal, psychiatric, cardiovascular or respiratory diagnoses. The population-based design made it possible to examine dose–response and potential gender differences in the associations. Methods About 1.8 million men and women aged 44–63 years and registered as living in Sweden in 2005 were followed regarding disability pension during 2006–2016, until ages 55–65 years. Mean values of physical workload and job control, estimated through gender-specific job-exposure matrices (JEMs), were assigned to individuals through their occupational titles in 2005. Exposure values were ranked separately for women and men and divided into quintiles. Associations were analyzed with Cox proportional-hazards regression. Results The analyses showed robust, dose–response associations between physical workload and disability pension with a musculoskeletal diagnosis in both genders: the adjusted hazard ratio and 95% confidence interval for those with the heaviest exposure was 2.58 (2.37–2.81) in women and 3.34 (2.83–3.94) in men. Dose–response associations were also seen in relation to disability pension with a cardiovascular or a respiratory diagnosis, though the hazard ratios were smaller. Physical workload was not associated with disability pension with a psychiatric diagnosis after adjustment for job control. Conclusion This study of the entire Swedish population of middle-aged and older workers suggests that higher degrees of physical workload may increase the risk of disability pension overall, and specifically with musculoskeletal, cardiovascular or respiratory diagnosis, in both women and men.

Introduction Body mass index (BMI) is a composite variable of weight and height, often used as a predictor of health outcomes, including mortality. The main purpose of combining weight and height in one variable is to obtain a measure of obesity independent of height. It is however unclear how accurate BMI is as a predictor of mortality compared with models including both weight and height or a weight × height interaction as predictors. Methods The current study used conscription data on weight, height, and BMI of Swedish men (N = 48,904) in 1969/70 as well as linked data on mortality (3442 deaths) between 1969 and 2008. Cox proportional hazard models including combinations of weight, height, and BMI at conscription as predictors of subsequent all‐cause and cause‐specific mortality were fitted to data. Results An increase by one standard deviation on weight and BMI were associated with an increase in hazard for all‐cause mortality by 5.4% and 11.5%, respectively, while an increase by one standard deviation on height was associated with a decrease in hazard for all‐cause mortality by 9.4%. The best‐fitting model indicated lowest predicted all‐cause mortality for those who weighed 60.5 kg at conscription, regardless of height. Further analyses of cause‐specific mortality suggest that this weight seems to be a compromise between lower optimal weights to avoid cancer and CVD mortality and a higher optimal weight to not die by suicide. Conclusions According to the present findings, there are several ways to make better use of measured weight and height than to calculate BMI when predicting mortality.

Background Psychosocial workplace factors may be associated with alcohol-related morbidity, but previous studies have had limited opportunities to take non-occupational explanatory factors into account. The aim of this study is to investigate associations between job control, job demands and their combination (job strain) and diagnosed alcohol-related morbidity while accounting for several potentially confounding factors measured across the life-course, including education. Methods Job control, job demands and job strain were measured using the Swedish job exposure matrix measuring psychosocial workload on the occupational level linked to over 3 million individuals based on their occupational titles in 2005 and followed up until 2016. Cox regression models were built to estimate associations with alcohol-related diagnoses recorded in patient registers. Results Low job control was associated with an increased risk of alcohol-related morbidity, while high job demands tended to be associated with a decreased risk. Passive and high-strain jobs among men and passive jobs among women were also associated with an increased risk of alcohol diagnoses. However, all associations were found to be weakened in models adjusted for other factors measured prospectively over the life-course, especially in models that included level of education. Conclusion The associations between low job control and high job demands, and the risk of alcohol-related morbidity reflect underlying socioeconomic differences to some extent. Lower job control, however, remained associated with a higher risk of alcohol-related morbidity.

ObjectiveTo investigate the association between job control, job demands and their combination (job strain) and suicide attempts and deaths among male and female workers in Sweden.MethodsJob control and demands were measured separately for men and women using a job exposure matrix, which was linked to around three million individuals based on their occupational title in 2005. Suicide attempts and deaths were measured in the hospital and cause of death registers from 2006 to 2016. HRs were estimated using discrete proportional hazards models with annually updated age as the time axis. Models were adjusted for sociodemographic, family, health, labour market and childhood factors, as well as the time-varying effects of unemployment, sick leave and family factors during follow-up.ResultsLow job control was associated with an increased risk of suicide attempts and deaths among both men and women while high job demands tended to be associated with a decreased risk. The combination of job control and job demands (job strain) reflected the increased risk of low control jobs and the decreased risk of high demand jobs. Associations were attenuated but still present after adjustments.ConclusionsLow job control is related to suicide attempts and deaths, and this is only partially explained by important covariates measured both prebaseline and during follow-up. Attempts to increase job control among workers may be beneficial in preventing suicide.

We identified occupations with a high incidence of prolonged sickness absence (SA) in Nordic employees and explored similarities and differences between the countries. Utilizing data from national registers on 25–59-year-old wage-earners from Denmark, Finland, Norway and Sweden, we estimated the gender- and occupation-specific age-adjusted cumulative incidence of SA due to any cause, musculoskeletal diseases and mental disorders. To increase the comparability of occupations between the countries, we developed a Nordic crosswalk for occupational codes. We ranked occupational groups with the incidence of SA being statistically significantly higher than the population average of the country in question and calculated excess fractions with the employee population being the reference group. We observed considerable occupational differences in SA within and between the countries. Few occupational groups had a high incidence in all countries, particularly for mental disorders among men. In each country, manual occupations typically had a high incidence of SA due to any cause and musculoskeletal diseases, while service occupations had a high incidence due to mental disorders. Preventive measures targeted at specific occupational groups have a high potential to reduce work disability, especially due to musculoskeletal diseases. Particularly groups with excess SA in all Nordic countries could be at focus.

The effect of higher education on intelligence has been examined through analyses of longitudinal data. Such studies typically have found a positive effect on the order of 1 IQ point per year of higher education in analyses where pre-education intelligence was included as a covariate. Unfortunately, this statistical technique is known to yield positively biased results if the covariate has measurement errors and is correlated with the predictor. At the same time, a negative bias arises if the intelligence measure after higher education has a ceiling effect, as in data from the 1970 British Cohort Study that were used in a recent study on the effect of higher education. Here, we develop a method that combines mathematical analysis and simulations to account for both aspects of limited reliability of intelligence measures. When we apply this method in a reanalysis of the data from the 1970 British Cohort Study, we find that the estimated effect of higher education is reduced to 0.4 IQ points per year. We also find that the effect of higher education appears to be somewhat larger in the first two years of higher education, consistent with diminishing marginal cognitive benefits of education.

BackgroundBoth low intelligence and low emotional control have previously been linked to a higher risk of suicide, but it is unknown whether the associations apply consistently over the life course.MethodsThe study was based on data on intelligence and emotional control, collected from 48 738 Swedish men conscripted in 1969–1970, at ages 18–20 years. The data were linked to national registers giving information on subsequent suicidal behavior (completed and attempted suicide) up to the age of 59 years. The associations were investigated using logistic regression and Cox proportional hazards regression models, with adjustment for childhood socioeconomic status.ResultsIntelligence and emotional control assessed in late adolescence both showed robust inverse associations with suicidal behavior over the 38-year follow-up. However, while the association between lower intelligence and higher rate of suicidal behavior remained the same throughout (~40% increased hazard per unit on a five-level scale), the association between lower emotional control and suicidal behavior was substantially stronger in early adulthood (~100% increased hazard per unit) than in late middle age (~30% increased hazard per unit).ConclusionsThe study adds to previous research by showing that the association between poor emotional control and subsequent suicide risk in men becomes weaker over the life course, while the association between low intelligence and suicide risk seems to be constant. The particularly high suicide risk of young men with poor emotional control may motivate targeted prevention efforts.

Earlier research has identified personality traits × intelligence interaction effects on academic performance. The present study, employing data from the 1997 National Longitudinal Survey of Youth (NLSY97, N = 8984), identified some interaction effects, mainly involving indicators of dependability, on high school grades. The interaction effects tended to be synergistic, meaning that the association between the trait and grades tended to strengthen with increased intelligence. This could be due to a sufficient level of intelligence being necessary for higher grades, and that lack thereof cannot be compensated for by a high degree of some advantageous personality trait. However, a positive association between intelligence and reliability in the measurement of personality, as well as a reversed causal effect of grades on self-rated personality moderated by intelligence, could also be contributing causes to the tendency for synergistic interaction effects.

BackgroundHigh job demands, low job control, and their combination (job strain) may increase workers' risk of depression. Previous research is limited by small populations, not controlling for previous depression, and relying on the same informant for reporting exposure and outcome. This study aims to examine the relationship between objectively measured workplace factors and the risk of developing clinical depression among the Swedish working population while controlling for previous psychiatric diagnoses and sociodemographic factors.MethodsControl, demands, and job strain were measured using the Swedish Job Exposure Matrix (JEM) measuring psychosocial workload linked to around 3 million individuals based on their occupational titles in 2005. Cox regression models were built to estimate associations between these factors and diagnoses of depression recorded in patient registers.ResultsLower job control was associated with an increased risk of developing depression (HR 1.43, 95% CI 1.39–1.48 and HR 1.27, 95% CI 1.24–1.30 for men and women with the lowest control, respectively), and this showed a dose–response relationship among men. Having high job demands was associated with a slight decrease in depression risk for men and women. High strain and passive jobs (both low control jobs) were associated with an increased risk of depression among men, and passive jobs were associated with an increased risk among women.ConclusionHigh job control appears important for reducing the risk of developing depression even when accounting for previous psychiatric diagnoses and sociodemographic factors. This is an important finding concerning strategies to improve occupational and in turn mental health.

BMI has been used as a predictor of health outcomes, including mortality, in numerous studies. However, in the present study of Swedish male conscripts with follow ups (N = 48,904, 3442 deaths), we show that there are several better ways to use measured weight and height than to calculate BMI when predicting mortality. The most accurate model indicated lowest predicted all-cause mortality for those who weighed 60.5 kg at conscription, regardless of height. This weight seems to be a compromise between lower optimal weights to avoid cancer and CVD mortality and a higher optimal weight to avoid suicide.

We examined the associations between fathers’ alcohol consumption and total and cause-specific mortality in adult offspring. Fathers’ alcohol consumption was associated with increased risk of alcohol-related mortality in offspring. The association appeared to be weaker for causes of death in which alcohol plays a smaller, or less direct, role., Aim This study examined associations between fathers’ alcohol consumption and risk for total and cause-specific mortality in offspring. Short summary We examined the associations between fathers’ alcohol consumption and total and cause-specific mortality in adult offspring. Fathers’ alcohol consumption was associated with increased risk of alcohol-related mortality in offspring. The association appeared to be weaker for causes of death in which alcohol plays a smaller, or less direct, role. Methods Data on fathers’ alcohol consumption, and offspring’s risky use of alcohol, smoking, mental health and contact with police/childcare authorities were collected among 46,284 men (sons) aged 18–20 years, during conscription for compulsory military training in 1969/70. Data on offspring mortality were obtained from the National Cause of Death register, 1971–2008. The mortality outcomes included total mortality, alcohol-related causes of death and violent causes of death (categorized into suicides vs violent/external causes excluding suicides). Results Compared to sons whose fathers never used alcohol, the risk for total and alcohol-related mortality among sons increased with the father’s consumption level. The risk of violent death was significantly elevated among sons whose fathers drank alcohol occasionally or often, but the risk of suicide increased in the highest consumption category only. After adjustment for covariates, the results remained for alcohol-related mortality whereas they were significantly attenuated, or disappeared, for total mortality, violent death and suicide. Conclusions Fathers’ alcohol consumption is associated with increased risk of alcohol-related mortality in the offspring. Alcohol use among fathers also increases the offspring’s risk of later total mortality, suicide and violent death, but these associations appear to be mediated or confounded by factors related to parental drinking and/or adverse childhood psychosocial circumstances.

Background Both low intelligence and low emotional control have previously been linked to a higher risk of suicide, but it is unknown whether the associations apply consistently over the life course. Methods The study was based on data on intelligence and emotional control, collected from 48 738 Swedish men conscripted in 1969–1970, at ages 18–20 years. The data were linked to national registers giving information on subsequent suicidal behavior (completed and attempted suicide) up to the age of 59 years. The associations were investigated using logistic regression and Cox proportional hazards regression models, with adjustment for childhood socioeconomic status. Results Intelligence and emotional control assessed in late adolescence both showed robust inverse associations with suicidal behavior over the 38-year follow-up. However, while the association between lower intelligence and higher rate of suicidal behavior remained the same throughout (~40% increased hazard per unit on a five-level scale), the association between lower emotional control and suicidal behavior was substantially stronger in early adulthood (~100% increased hazard per unit) than in late middle age (~30% increased hazard per unit). Conclusions The study adds to previous research by showing that the association between poor emotional control and subsequent suicide risk in men becomes weaker over the life course, while the association between low intelligence and suicide risk seems to be constant. The particularly high suicide risk of young men with poor emotional control may motivate targeted prevention efforts.

Some studies have analyzed the effect of a predictor measured at a later time point (X1), or of the X1-X0 difference, while adjusting for the predictor measured at baseline (X0), on some outcome Y of interest. The present simulation study shows that, if used to analyze the effect of change in X on Y, there is a high risk for this analysis to produce type 1-errors, especially with a strong correlation between true X and Y, when X0 and X1 are not measured with very high reliability, and with a large sample size. These problems are not encountered if analyzing the unadjusted effect of the X1-X0 difference on Y instead, and as this effect exhibits power on par with the adjusted effect it seems as the preferable method when using change between two measurement points as a predictor.

Background\ud \ud The incidence of major depression among adults has been shown to be socially differentiated, and there are reasons to seek explanations for this before adulthood. In this cohort study, we examined whether academic performance in adolescence predicts depression in adulthood, and the extent to which externalizing disorders explain this association.\ud \ud \ud Methods\ud \ud We followed 26,766 Swedish women and men born 1967–1982 from the last year of compulsory school, at age about 16, up to 48 years of age. We investigated the association between grade point average (GPA, standardized by gender) and first diagnosis of depression in national registers of in- or out-patient psychiatric care. We used Cox proportional hazards models, adjusting for lifetime externalizing diagnoses and potential confounders including childhood socioeconomic position and IQ.\ud \ud \ud Results\ud \ud During follow-up, 7.0% of the women and 4.4% of the men were diagnosed with depression. A GPA in the lowest quartile, compared with the highest, was associated with an increased risk in both women (hazard ratio 95% confidence interval 1.7, 1.3–2.1) and men (2.9, 2.2–3.9) in models controlling for potential confounders. Additional control for externalizing disorders attenuated the associations, particularly in women.\ud \ud \ud Conclusions\ud \ud The findings suggest that poor academic performance is associated with depression in young adulthood and that the association is partly explained by externalizing disorders. Our results indicate the importance of early detection and management of externalizing disorders among children and adolescents.

ObjectiveWe aimed to quantify the mediating impact of adult social and behavioural mechanisms in the association between childhood socioeconomic position (SEP) and cardiovascular disease (CVD) mortality by employing a weighting approach to mediation analysis.DesignProspective cohort study.SettingStockholm County, Sweden.Participants19 720 individuals who participated in the Stockholm Public Health Cohort survey in 2002 and were older than 40 years.Primary and secondary outcome measuresThe primary outcome was CVD mortality. Non-CVD mortality was additionally analysed for comparison.MethodsStudy subjects were followed in routine registers from 2002 to 2011 for mortality. Data on father’s SEP and adult social and behavioural factors came from questionnaire survey. The inverse odds weighting method was used to estimate the total effect, the natural direct effect and the natural indirect effect (NIE) in Poisson regression models. All results were adjusted for gender, age, country of birth and marital status. Multiple imputation was used to handle missing data.ResultsThe total effect of manual versus non-manual father’s SEP on CVD mortality was estimated as an incidence rate ratio (IRR) of 1.24 (95% CI 1.09 to 1.41). When the social and behavioural factors were accounted for, the IRR for the NIE was 1.09 (95% CI 1.04 to 1.14), suggesting a mediation of 44% of the total effect. As for non-CVD mortality, father’s manual SEP was associated with 1.15 fold excess risk (IRR: 1.15; 95% CI 1.04 to 1.27) of which the effect represented by the whole set of mediators was 1.06 (95% CI 1.01 to 1.10).ConclusionAdult social and behavioural factors had a considerable mediating effect on the early life social origin of mortality from CVDs and other causes. Future research employing causal mediation analysis may nevertheless have to consider additional factors for a fuller understanding of the mechanisms.

Background The developmental origins of ischemic heart disease (IHD) have been widely documented but little is known about their persistence across more than one generation. This study aimed to investigate whether the effects of early life disadvantages on adult IHD have changed between generations and are mediated by adult socioeconomic circumstances, and further explore the transgenerational effects of grandparental and parental exposures to disadvantaged circumstances on adult offspring's IHD. Methods We used register-based data from the Uppsala Multigenerational Study, Sweden. The study populations were the parents born 1915–1929 and their offspring born 1932–1972 with available obstetric data. The offspring were further linked to grandparents who had their socioeconomic and demographic data recorded. The outcome was incident IHD assessed at ages 32–75 during a follow-up from January 1, 1964 till December 31, 2008. The exposures included birthweight standardized-for-gestational age, ponderal index, gestational length, and parental socioeconomic position (SEP). Education and income were analyzed as mediators. Potential transgenerational associations were explored by linking offspring IHD to parents' standardized birthweight and gestational length, grandparental SEP, and to grandmothers’ age, parity, and marital status at parental birth. All associations were examined in Cox proportional hazard regression models. Results Lower standardized birthweight and lower parental SEP were found to be associated with higher IHD rates in both generations, with no evidence of effect modification by generation. Education and income did not mediate the association between standardized birthweight and IHD. Disadvantaged grandparental SEP, younger and older childbearing ages of grandmothers, and paternal preterm birth affected offspring's IHD independent of parental education, income, or IHD history. Conclusions The findings point to similar magnitudes of IHD inequalities by early life disadvantages across two historical periods and the existence of transgenerational effects on IHD. Epigenetic dysregulation involving the germline is a plausible candidate mechanism underlying the transgenerational associations that warrant further research.

Aims To examine associations between cannabis use in adolescence (at age 18) and unemployment and social welfare assistance in adulthood (at age 40) among Swedish men. Design Longitudinal cohort study. Setting and Participants A total of 49 321 Swedish men born in 1949–51, who were conscripted to compulsory military service at 18–20 years of age. Measurements All men answered two detailed questionnaires at conscription and were subject to examinations of physical aptitude psychological functioning and medical status. By follow-up in national databases, information on unemployment and social welfare assistance was obtained. Findings Individuals who used cannabis at high levels in adolescence had increased risk of future unemployment and of receiving social welfare assistance. Adjusted for all confounders (social background, psychological functioning, health behaviours, educational level, psychiatric diagnoses), an increased relative risk (RR) of unemployment remained in the group reporting cannabis use > 50 times [RR = 1.26, 95% confidence interval (CI) = 1.04–1.53] only. For social welfare assistance, RR in the group reporting cannabis use 1–10 times was 1.15 (95% CI = 1.06–1.26), RR for 11–50 times was 1.21 (95% CI = 1.04–1.42) and RR for > 50 times was 1.38 (95% CI = 1.19–1.62). Conclusions Heavy cannabis use among Swedish men in late adolescence appears to be associated with unemployment and being in need of social welfare assistance in adulthood. These associations are not explained fully by other health-related, social or behavioural problems.

Objective: Academic performance in youth, measured by grade point average (GPA), predicts suicide attempt, but the mechanisms are not known. It has been suggested that general intelligence might underlie the association. Methods: We followed 26 315 Swedish girls and boys in population-representative cohorts, up to maximum 46 years of age, for the first suicide attempt in hospital records. Associations between GPA at age 16, IQ measured in school at age 13 and suicide attempt were investigated in Cox regressions and mediation analyses. Results: There was a clear graded association between lower GPA and subsequent suicide attempt. With control for potential confounders, those in the lowest GPA quartile had a near five-fold risk (HR 4.9, 95% CI 3.7-6.7) compared to those in the highest quartile. In a mediation analysis, the association between GPA and suicide attempt was robust, while the association between IQ and suicide attempt was fully mediated by GPA. Conclusions: Poor academic performance in compulsory school, at age 16, was a robust predictor of suicide attempt past young adulthood and seemed to account for the association between lower childhood IQ and suicide attempt.

New data on cause of death suggest the link is mediated by risk factors such as smoking

First, we express our appreciation of the comments on our study by Kawada and by Behrouz and Aachi. We seem to agree on the value of studies on this matter. In both letters, the authors highlight that cannabis use in our study (as well as tobacco and alcohol use) could be measured only in late adolescence and, as a result, little is known about its prevalence later, when cases of stroke occur. Therefore, the authors suspect that our analysis could have missed an association between cannabis use in adulthood and stroke events. This cannot be ruled out, which we touched on in the discussion of our results. However, some prevalence of cannabis use in adulthood is still expected, and we think that in such cases, it was generally preceded by teenage use. With regard to tobacco smoking, >90% of those who were smokers later in life already smoked before …

Background Lower intelligence early in life is associated with increased risks for coronary heart disease (CHD) and mortality. Intelligence level might affect compliance to treatment but its prognostic importance in patients with CHD is unknown. Methods A cohort of 1923 Swedish men with a measure of intelligence from mandatory military conscription in 1969–1970 at age 18–20, who were diagnosed with CHD 1991–2007, were followed to the end of 2008. Primary outcome: recurrent CHD event. Secondary outcome: case fatality from the first event, cardiovascular and all-cause mortality. National registers provided information on CHD events, comorbidity, mortality and socioeconomic factors. Results The fully adjusted HRs for recurrent CHD for medium and low intelligence, compared with high intelligence, were 0.98, (95% CIs 0.83 to 1.16) and 1.09 (0.89 to 1.34), respectively. The risks were increased for cardiovascular and all-cause mortality with lower intelligence, but were attenuated in the fully adjusted models (fully adjusted HRs for cardiovascular mortality 1.92 (0.94 to 3.94) and 1.98 (0.89 to 4.37), respectively; for all-cause mortality 1.63 (1.00 to 2.65) and 1.62 (0.94 to 2.78), respectively). There was no increased risk for case-fatality at the first event (fully adjusted ORs 1.06 (0.73 to 1.55) and 0.97 (0.62 to 1.50), respectively). Conclusions Although we found lower intelligence to be associated with increased mortality in middle-aged men with CHD, there was no evidence for its possible effect on recurrence in CHD.

This study investigated how psychological distress and the proxies for social position combine to influence the risk of both underweight and overweight in South Africans aged 15 years and older. This was a cross-sectional study that included 2254 men and 4170 women participating in the first South African National Health and Nutrition Examination Survey (SANHANES-1). An analysis exploring the associations of social and mental health characteristics with body mass index (BMI) was conducted using binary and multinomial logistic regressions. Results suggested that, overall, women had a higher risk of overweight/obesity compared to men (age-adjusted odds ratio [AOR] 4.65, 95% confidence intervals [CI] 3.94&ndash, 5.50). The gender effect on BMI was smaller in non-African participants (AOR 3.02, 95% CI 2.41&ndash, 3.79, p-value for interaction = 0.004). Being employed and having a higher level of education were associated with higher risks of overweight and obesity and a lower risk of underweight. Being single or without a spouse and poor mental health were found to increase the odds of being underweight, especially in men. To conclude, there are strong social gradients and important gender and ethnic differences in how BMI is distributed in the South African population.

BackgroundIn Sweden, the proportion of the population that remains in paid employment until normal retirement age of 65 years is less than 50% in blue-collar groups, compared to 60%–75% in white-collar occupations. High physical workload has been associated with early exits from the labor market through disability pensions (DP) in many studies. However, identified risk factors for DP from early life may be more prevalent among men in heavy manual occupations than in others. The aim was to investigate the association between high physical work load in middle age and DP before age 59, adjusting for social background, physical ability, psychological characteristics, lifestyle and education measured before labour market entrance.MethodsThe study is based on a Swedish conscription cohort of 49 321 men born 1949–1951. At enlistment 1969/1970 information was collected about cardiorespiratory fitness, social background, psychological characteristics and health behaviours, e.g. smoking. Physical workload was estimated with a job exposure matrix based on questions concerning heavy lifting, strenuous work postures, repetitive work and physically strenuous work from the Swedish Work Environment Surveys 1989–97. Mean values for men of a composite physical exposure variable were grouped into quartiles; high, medium-high, medium-low and low physical workload, and assigned to occupational titles from the census 1990. The study group was followed regarding DP from age 40 to 59.ResultsExposure to high (HR 2.67, CI 95% 2.42–2.95), medium-high (HR 2.43, CI 95% 2.20–2.69) and medium-low (HR 1.31, CI 95% 1.18–1.47) physical workload, compared with low, were associated with DP up to age 59. The increased risks remained, but were clearly attenuated after adjustments for pre-labour market factors, especially psychological characteristics and education.ConclusionThe results are in line with a major effect of high physical work load on disability pension, even though adjustments for pre-labour market factors clearly attenuated the risks.

BackgroundThe association between level of education and disability pension (DP) is well known. Earlier studies have investigated the importance of early life factors and work characteristics but not in combination. The aim of this study was to investigate the association between level of education and DP among Swedish middle-aged working men and to what extent such an association can be explained by factors measured in late adolescence and work characteristics in adulthood.MethodsInformation about IQ, health-related lifestyle factors, psychiatric and musculoskeletal diagnoses was obtained from the 1969 conscription cohort, consisting of 49 321 Swedish men. Data collected when subjects were 18–20 years of age were combined with national register-based information about level of education, job control and physical strain at work in adulthood, and information about DP between 1991 and 2002.ResultsThere was a strong graded association between level of education and DP. Those with the lowest level of education had a four times greater probability of having DP as compared with those with the highest level. In multivariable analyses, factors measured in late adolescence, IQ in particular, attenuated the association more than work-related characteristics in adulthood.ConclusionsThe authors found an association between level of education and DP among Swedish middle-aged working men. A large part of the association was explained by factors measured in late adolescence, IQ in particular, and somewhat less by work characteristics measured in adulthood. Level of education remained as a significant predictor of DP in middle age after full adjustment.

Background: Being male constitutes a risk factor for early death, and this may be connected to concepts of masculinity. The objective of the present study was to investigate the association between masculinity rank during late adolescence and mortality patterns in a cohort of 49 321 Swedish men tested for compulsory military training in 1969. Methods: The measure of masculinity consisted of a fivegrade ranking from the conscription information that comprised leisure interests and occupational preferences. Information on all-cause mortality, alcohol-related mortality, suicide, mortality from other violent causes and mortality from cardiovascular disease was collected from national registers for 1970‐2003. The analyses were performed using Cox proportional hazard models with hazard ratios as estimates of relative risk. Results: For all-cause mortality, the crude relative risks versus ordinary masculinity were: lowest masculinity 1.98 (95% CI 1.71 to 2.31), low masculinity 1.38 (95% CI 1.24 to 1.53), high masculinity 0.90 (95% CI 0.81 to 1.01) and highest masculinity 0.78 (95% CI 0.62 to 0.97). After adjustments for childhood class, smoking, alcohol drinking, blood pressure, short stature, psychiatric disorder, low intelligence and contact with police or childcare authorities, conscripts who were ranked lowest on masculinity had a remaining increased relative risk of allcause mortality (1.49; 95% CI 1.28 to 1.75) and suicide (1. 79; 95% CI 1.31 to 2.43). For mortality from violent causes other than suicide, no statistically significant associations were demonstrated. Conclusions: Earlier research has proposed that masculinity may hold both positive and negative aspects regarding lifetime health. The major conclusion here is that being ranked less masculine is associated with higher mortality.

ObjectiveTo investigate the association between intelligence and disability pension due to mental, musculoskeletal, cardiovascular, and substance-use disorders among men and women, and to assess the role of childhood social factors and adulthood work characteristics.MethodsTwo random samples of men and women born 1948 and 1953 (n = 10 563 and 9 434), and tested for general intelligence at age 13, were followed in registers for disability pension until 2009. Physical and psychological strains in adulthood were assessed using job exposure matrices. Associations were examined using Cox proportional hazard regression models, with increases in rates reported as hazard ratios (HRs) with 95% confidence intervals (95%CI) per decrease in stanine intelligence.ResultsIn both men and women increased risks were found for disability pension due to all causes, musculoskeletal disorder, mental disorder other than substance use, and cardiovascular disease as intelligence decreased. Increased risk was also found for substance use disorder in men. In multivariate models, HRs were attenuated after controlling for pre-school plans in adolescence, and low job control and high physical strain in adulthood. In the fully adjusted model, increased HRs remained for all causes (male HR 1.11, 95%CI 1.07-1.15, female HR 1.06, 95%CI 1.02-1.09) and musculoskeletal disorder (male HR 1.16, 95%CI 1.09-1.24, female HR 1.08, 95%CI 1.03-1.14) during 1986 to 2009.ConclusionRelatively low childhood intelligence is associated with increased risk of disability pension due to musculoskeletal disorder in both men and women, even after adjustment for risk factors for disability pension measured over the life course.

Body mass index (BMI) in adolescence may be of particular importance as a predictor of future risk of coronary heart disease (CHD). Associations measured either in childhood or in middle age have appeared to be weaker or non-existent. We investigated the association between BMI measured in adolescence and CHD, and also stroke, among middle aged Swedish men and controlled for potential confounders not included in previous studies.Data on BMI, smoking and blood pressure (diastolic and systolic) was collected from 49,321 Swedish males, born during 1949-1951, at conscription for military service in 1969/70. Census data on socioeconomic indicators in childhood and adulthood was linked to the cohort. The men were followed from 1991 through 2004 in national registers with regard to mortality and hospitalization from CHD and stroke.A graded increase of CHD was seen in over six levels of BMI (BMI18.5, hazard ratio (HR)=1.0, BMI=18.5-20.99 (reference category), BMI=21-22.99, HR=1.2; BMI=23-24.99, HR=1.5; BMI=25-29.99, HR=2.5; BMIor =30, HR=4.3). A graded association between BMI and stroke was also found, although weaker. Adjustments for cardiovascular risk factors (smoking, diastolic and systolic blood pressure, and early cardiovascular mortality in parents) attenuated the relative risks to some extent, whereas adjustments for socioeconomic indicators in childhood and adulthood had minor effects.The results strongly suggest that BMI in late adolescence is an important predictor of both CHD and stroke among men before age 55 years, independent of smoking, hypertension and early cardiovascular mortality in parents.