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We assessed potential relations between indicators of indoor dampness and mold exposures at home and the level of asthma control among adults. The present population-based cross-sectional study, the Northern Finnish Asthma Study (NoFAS), included 1995 adult subjects with bronchial asthma who replied to study questionnaires (response rate: 40.4%). The Asthma Control Test (ACT) was used as the measure of asthma control. We calculated the mean difference in ACT score (ACTdifference) and the risk ratio (RR) of poor asthma control (ACT ≤ 19) for the exposure and reference groups and applied Poisson regression to adjust for potential confounding. Exposure to indoor dampness at home was related to a significantly reduced level of asthma control (ACTdifference: −0.83, 95% CI: −1.60 to −0.07), especially among men (ACTdifference: −2.68, 95% CI: −4.00 to −1.37). Water damage (aRR = 1.29, 95% CI: 1.01, 1.65) and indoor dampness, especially among men (aRR = 1.92, 95% CI: 1.15, 3.20), increased the risk of poor asthma control. We provide evidence that exposure to indoor dampness at home reduces asthma control among adults, especially in men. Indoor visible mold and mold odor were not significantly related to asthma control. Advice on how to prevent indoor dampness at home should be an important part of asthma management.

BackgroundWe hypothesised that occupational exposures differently affect subtypes of adult-onset asthma.ObjectiveWe investigated potential relations between occupation and three subtypes of adult asthma, namely atopic asthma, non-atopic asthma and asthma–COPD overlap syndrome (ACOS).MethodsThis is a population-based case–control study of incident asthma among working-age adults living in Pirkanmaa Hospital District in Southern Finland. The determinant of interest was occupation at the time of diagnosis of asthma or the job that the subject had quit due to respiratory symptoms. Asthma was divided into three mutually exclusive subtypes on the basis of any positive IgE antibody (atopic and non-atopic asthma) and presence of persistent airways obstruction in spirometry (ACOS). We applied unconditional logistic regression analysis to estimate adjusted OR (aOR), taking into account gender, age and smoking.ResultsThe following occupational groups showed significantly increased risk of atopic asthma: chemical industry workers (aOR 15.76, 95% CI 2.64 to 94.12), bakers and food processors (aOR 4.69, 95% CI 1.18 to 18.69), waiters (aOR 4.67, 95% CI 1.40 to 15.56) and those unemployed (aOR 3.06, 95% CI 1.52 to 6.17). The following occupations showed clearly increased risk of non-atopic asthma: metal workers (aOR 8.37, 95% CI 3.77 to 18.59) and farmers and other agricultural workers (aOR 2.36, 95% CI 1.10 to 5.06). Some occupational groups showed statistically significantly increased OR of ACOS: electrical and electronic production workers (aOR 30.6, 95% CI 6.10 to 153.35), fur and leather workers (aOR 16.41, 95% CI 1.25 to 215.85) and those retired (aOR 5.55, 95% CI 1.63 to 18.97).ConclusionsOur results show that different occupations are associated with different subtypes of adult-onset asthma.

Objective Exposures at hairdressers’ work have been reported to lead to an increased risk of several health outcomes. The present study aimed to investigate the relations between occupational exposures and respiratory symptoms and lung function among hairdressers in Iran. Methods We conducted a cross-sectional study to compare potential respiratory effects among 140 women working as hairdressers to such effects among 140 women working as office workers (administrative personnel). Both groups worked in Shiraz, Iran. Respiratory symptoms were assessed by a standard respiratory questionnaire. The questionnaire also inquired about substances used and workspace conditions, including ventilation type. Lung function levels were measured by spirometry. Results Respiratory symptoms, including cough, wheezing, shortness of breath, and chest tightness were significantly more frequent in hairdressers compared to the reference group (p p p Conclusions This study provides evidence of increased prevalence of respiratory symptoms and restrictive lung function impairment among hairdressers in Iran.

ObjectiveThe objective of this study was to investigate the potential effects of occupational exposures among fruit and vegetable market workers on the occurrence of respiratory symptoms and on the level of lung function parameters.MethodsWe conducted a cross-sectional study of 140 men working as fruit and vegetable market workers (response rate 100%) and a reference group of 77 male office workers as the reference group (response rate 55%) from Shiraz, Iran. The outcomes of interest included occurrence of respiratory symptoms assessed by a standard respiratory questionnaire and lung function assessed by spirometry.ResultsIn Poisson regression analyses, the exposed group showed increased prevalence ratio (PR) of wheezing (adjusted PR 5.32, 95% CI 1.40 to 20.26), after controlling for confounding. Cough (PR 3.30, 95% CI 1.16 to 9.40) and wheezing (PR 9.40, 95% CI 2.28 to 38.64) showed increased PRs among vegetable distributors. Forced expiratory volume in 1 s (FEV1) and FEV1/forced vital capacity were significantly decreased among exposed workers after controlling for confounders. The absolute value of FEV1 level was reduced significantly among fruit and vegetable carters (−0.99, 95% CI −1.68 to −0.32) and vegetable (−0.51, 95% CI −0.93 to −0.10) and fruit (−0.51, 95% CI −0.86 to −0.15) distributors in comparison with the reference group in the adjusted full model.ConclusionsThis study provides evidence that fruit and vegetable market workers are at an increased risk of respiratory symptoms and reduced lung function. Workplace conditions and safety training clearly need improvement, and there is a likely role for proper use of personal protective equipment.

(1) Poor asthma control increases the occurrence of cold weather-related symptoms among adult asthmatics. We assessed whether the subtype of asthma, taking into account the severity of the asthma, plays a role in these symptoms. (2) We conducted a population-based cross-sectional study of 1995 adult asthmatics (response rate 40.4%) living in northern Finland using a questionnaire that asked about cold weather-related respiratory symptoms including (1) shortness of breath, (2) prolonged cough, (3) wheezing, (4) phlegm production, and (5) chest pain, as well as questions related to the subtype of asthma. For women, the subtypes identified using latent class analysis were: (1) Controlled, mild asthma, (2) Partly controlled, moderate asthma, (3) Uncontrolled, unknown severity, and (4) Uncontrolled, severe asthma, and for men: (1) Controlled, mild asthma, (2) Uncontrolled, unknown severity, and (3) Partly controlled, severe asthma. (3) According to the subtypes of asthma, more severe and more poorly controlled asthma were related to the increased prevalence of cold weather-related respiratory symptoms when compared with those with mild, controlled asthma. This trend was especially clear for wheezing and chest pain. For example, in men, the adjusted prevalence ratio of wheezing was 1.55 (95% CI 1.09-2.19) in uncontrolled asthma with unknown severity and 1.84 (95% CI 1.26-2.71) in partly controlled severe asthma compared with controlled, mild asthma. (4) Our study provides evidence for the influence of subtypes of asthma on experiencing cold weather-related respiratory symptoms. Both women and men reported more cold weather-related symptoms when their asthma was more severe and uncontrolled compared with those who had mild and well-controlled asthma.

Hospital work environment contains various biological and chemical exposures that can affect indoor air quality and have impact on respiratory health of the staff. The objective of this study was to investigate potential effects of occupational exposures on the risk of respiratory symptoms and lung function in hospital work, and to evaluate potential interaction between smoking and occupational exposures.We conducted a cross-sectional study of 228 staff members in a hospital and 228 employees of an office building as the reference group in Shiraz, Iran. All subjects completed a standardized ATS respiratory questionnaire and performed a spirometry test.In Poisson regression, the adjusted prevalence ratios (aPR) among the hospital staff were elevated for cough (aPR 1.90, 95% CI 1.15, 3.16), phlegm production (aPR 3.21, 95% CI 1.63, 6.32), productive cough (aPR 2.83, 95% CI 1.48, 5.43), wheezing (aPR 3.18, 95% CI 1.04, 9.66), shortness of breath (aPR 1.40, 95% CI 0.93, 2.12), and chest tightness (aPR 1.73, 95% CI 0.73, 4.12). Particularly laboratory personnel experienced increased risks of most symptoms. In linear regression adjusting for confounding, there were no significant differences in lung function between the hospital and office workers. There was an indication of synergism between hospital exposures and current smoking on FEV1/FVC% (interaction term β = - 5.37, 95% CI - 10.27, - 0.47).We present significant relations between hospital work, especially in laboratories, and increased risks of respiratory symptoms. Smoking appears to enhance these effects considerably. Our findings suggest that policymakers should implement evidence-based measures to prevent these occupational exposures.

We conducted a time-series analysis of the relations between daily levels of allergenic pollen and mortality in the Helsinki Metropolitan Area with 153 378 deaths; 9742 from respiratory and 57 402 from cardiovascular causes. Daily (average) pollen counts of alder, birch, mugwort and grass were measured. In quasi-Poisson regression analysis, abundant alder pollen increased the risk of non-accidental deaths with an adjusted cumulative mortality rate ratio (acMRR) of 1.10 (95% CI 1.01–1.19) and of deaths from respiratory-diseases with acMRR of 1.78 (95% CI 1.19–2.65). Abundant mugwort pollen increased cardiovascular mortality (1.41, 1.02–1.95). These findings identify an important global public health problem.

Significance COVID-19 has caused more than 2.5 million deaths worldwide. It is imperative that we develop therapies that can mitigate the effect of the disease. While searching for individual drugs for this purpose has been met with difficulties, synergistic drug combinations offer a promising alternative. However, the lack of high-quality training data pertaining to drug combinations makes it challenging to use existing machine learning methods for effective novel combination prediction tasks. Our proposed approach addresses this challenge by leveraging additional readily available data, such as drug−target interactions, thus enabling an effective in silico search for synergistic combinations against SARS-CoV-2., Effective treatments for COVID-19 are urgently needed. However, discovering single-agent therapies with activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been challenging. Combination therapies play an important role in antiviral therapies, due to their improved efficacy and reduced toxicity. Recent approaches have applied deep learning to identify synergistic drug combinations for diseases with vast preexisting datasets, but these are not applicable to new diseases with limited combination data, such as COVID-19. Given that drug synergy often occurs through inhibition of discrete biological targets, here we propose a neural network architecture that jointly learns drug−target interaction and drug−drug synergy. The model consists of two parts: a drug−target interaction module and a target−disease association module. This design enables the model to utilize drug−target interaction data and single-agent antiviral activity data, in addition to available drug−drug combination datasets, which may be small in nature. By incorporating additional biological information, our model performs significantly better in synergy prediction accuracy than previous methods with limited drug combination training data. We empirically validated our model predictions and discovered two drug combinations, remdesivir and reserpine as well as remdesivir and IQ-1S, which display strong antiviral SARS-CoV-2 synergy in vitro. Our approach, which was applied here to address the urgent threat of COVID-19, can be readily extended to other diseases for which a dearth of chemical−chemical combination data exists.

Introduction Dental caries and respiratory tract infections are among the most common infectious diseases worldwide and they both are appearing in the respiratory system. However, their relations are still unclear. This study investigated the association of dental caries on the risk of lower respiratory tract infections (LRTI) in young adulthood. Methods The study population consisted of 1,592 Finnish young adults participating in the 20-year follow-up of The Espoo Cohort Study. The information on the occurrence of LRTIs (pneumonia or acute bronchitis) during the preceding 12 months was based on the follow-up questionnaire and the National Hospital Discharge Register. Lifelong caries on permanent teeth was defined as a self-reported number of filled teeth (FT). The risk ratios (RR) of LRTIs with 95% confidence intervals (CI) were estimated using Poisson regression models. Results High FT number was associated with an increased occurrence of LRTIs with an adjusted RR of 1.24 per interquartile range (IQR) of FT (95% CI 1.06–1.44). The risk of LRTIs increased according to the increasing number of FTs, being highest among those subjects with 10 or more filled teeth (adjusted RR 2.30; 1.27–4.17). Family's socioeconomic status or smoking did not modify the effect. Conclusions Our results suggest that dental caries increases the risk of LRTIs. We did not find any significant effect modification by shared determinants of caries and LRTIs. However, it is possible, that common risk factors might explain at least partly the observed relation between FT and LRTIs or that the causality is bidirectional.

According to our systematic literature review, no previous study has assessed potential effects of regular exercise on asthma control among young adults. We hypothesized that regular exercise improves asthma control among young adults.We studied 162 subjects with current asthma recruited from a population-based cohort study of 1,623 young adults 20-27 years of age. Asthma control was assessed by the occurrence of asthma-related symptoms, including wheezing, shortness of breath, cough, and phlegm production, during the past 12 months. Asthma symptom score was calculated based on reported frequencies of these symptoms (range: 0-12). Exercise was assessed as hours/week.In Poisson regression, adjusting for gender, age, smoking, environmental tobacco smoke exposure, and education, the asthma symptom score reduced by 0.09 points per 1 hour of exercise/week (95% CI: 0.00 to 0.17). Applying the "Low exercise" quartile as the reference, "Medium exercise" reduced the asthma symptom score by 0.66 (-0.39 to 1.72), and "High exercise" reduced it significantly by 1.13 (0.03 to 2.22). The effect was strongest among overweight subjects.Our results provide new evidence that regular exercising among young adults improves their asthma control. Thus, advising about exercise should be included as an important part of asthma self-management in clinical practice.

BackgroundSeveral studies have assessed effects of short-term exposure to pollen on allergic and asthmatic manifestations. The evidence is inconclusive, and no meta-analysis has been published.ObjectiveTo synthesise the evidence on the relations between short-term pollen exposure and the risk of allergic and asthmatic manifestations.MethodsWe performed a systematic literature search of PubMed and Scopus databases up to the end of August 2018. In addition, we reviewed the reference lists of relevant articles. Two authors independently evaluated the eligible articles and extracted relevant information in a structured form. We calculated summary effect estimates (EE) based on the study-specific ORs and regression coefficients (β) by applying both fixed-effects and random-effects models.Results26 studies met the a priori eligibility criteria, and 12 of them provided sufficient information for the meta-analysis. The summary EE related to 10 grains per m³ increase in pollen exposure showed an 1% increase (EE 1.01, 95% CI 1.00 to 1.02) in the risk of lower respiratory symptoms and a 2% increase (EE 1.02, 95% CI 1.01 to 1.03) in the risk of any allergic or asthmatic symptom. Correspondingly, the risk of upper respiratory symptoms and ocular symptoms increased 7% (EE 1.07, 95% CI 1.04 to 1.09) and 11% (EE 1.11, 95% CI 1.05 to 1.17), respectively, in relation to such pollen exposure. Short-term exposure to pollen did not show any significant effect on daily lung function levels.ConclusionOur results provide new evidence that short-term pollen exposure significantly increases the risks of allergic and asthmatic symptoms.

Background Previous studies have provided evidence that prenatal exposure to low-level air pollution increases the risk of preterm birth (PTB), but the findings of the effects of short-term exposure have been inconclusive. Moreover, there is little knowledge on potential synergistic effects of different combinations of air pollutants. Objectives To assess independent and joint effects of prenatal exposure to air pollutants during the week prior to the delivery on the risk of PTB. Methods The study population included 2568 members of the Espoo Cohort Study, living in the City of Espoo, Finland, born between 1984 and 1990. We assessed individual-level prenatal exposure to ambient air pollutants of interest based on maternal residential addresses, while taking into account their residential mobility. We used both regional-to-city-scale dispersion modelling and land-use regression–based method to estimates the pollutant concentrations. We contrasted the risk of PTB in the highest quartile (Q4) of exposure to the lower exposure quartiles (Q1-Q3) during the specific periods of pregnancy. We applied Poisson regression analysis to estimate the adjusted risk ratios (RRs) with their 95% confidence intervals (CI), adjusting for season of birth, maternal age, sex of the baby, family's socioeconomic status, maternal smoking, and exposure to environmental tobacco smoke during pregnancy, single parenthood, and exposure to other air pollutants (this in multi-pollutant models). Results The risk of PTB was related to exposures to PM2.5, PM10 and NO2 during the week prior to the delivery with adjusted RRs of 1.67 (95%CI: 1.14, 2.46), 1.60 (95% CI: 1.09, 2.34) and 1.65 (95% CI: 1.14, 2.37), from three-pollutant models respectively. There were no significant joint effects for these different air pollutants (during the week prior to the delivery). Conclusion Our results provide evidence that exposure to fairly low-level air pollution may trigger PTB, but synergistic effects of different pollutants are not likely.

We conducted a randomized controlled trial to test the hypothesis that a 24-week exercise intervention improves asthma control in adults. Adults with mild or moderate asthma were randomly assigned to either the exercise intervention group (IG) or the reference group (RG). Participants in IG received an individualized exercising program, including aerobic exercise at least three times a week for ≥30 minutes, muscle training, and stretching. The primary outcome was asthma control, measured by Asthma Control Test (ACT), asthma-related symptoms, and peak expiratory flow (PEF) variability. We estimated the risk (i.e. probability) of improvement in asthma control and the risk difference (RD) between IG and RG. Of 131 subjects (67 IG/64 RG) entered, 105 subjects (51/54) completed the trial (80%), and 89 (44/45) were analysed (68%). The ACT became better among 26 (62%) participants in IG and among 17 (39%) participants in RG. The effect of intervention on improving asthma control was 23% (RD = 0.23, 95% CI 0.027–0.438; P = 0.0320). The intervention also reduced shortness of breath by 30.1% (RD = 0.301, 95% CI 0.109–0.492; P = 0.003). The change in PEF variability was similar in both groups. Regular exercise improves asthma control measured by the ACT, while has little effect on PEF variability.

There is some evidence that prenatal exposure to low-level air pollution increases the risk of preterm birth (PTB), but little is known about synergistic effects of different pollutants.We assessed the independent and joint effects of prenatal exposure to air pollution during the entire duration of pregnancy.The study population consisted of the 2568 members of the Espoo Cohort Study, born between 1984 and 1990, and living in the City of Espoo, Finland. We assessed individual-level prenatal exposure to ambient air pollutants of interest at all the residential addresses from conception to birth. The pollutant concentrations were estimated both by using regional-to-city-scale dispersion modelling and land-use regression-based method. We applied Poisson regression analysis to estimate the adjusted risk ratios (RRs) with their 95% confidence intervals (CI) by comparing the risk of PTB among babies with the highest quartile (QIn a multi-pollutant model estimating the effects of exposure during entire pregnancy, the adjusted RR was 1.37 (95% CI: 0.85, 2.23) for PMOur results strengthen the evidence that exposure to fairly low-level air pollution during pregnancy increases the risk of PTB. We provide novel observations indicating that individual air pollutants such as PM

Interleukin 6 (IL6) is an inflammatory cytokine that has been suggested to have an important role in the pathogenesis of asthma. IL6 single-nucleotide polymorphisms (SNPs) have been associated with levels of IL6, and with childhood and prevalent adult asthma. A recent study also suggested that IL6 SNPs associate especially with atopic asthma. However, association of IL6 SNPs with adult-onset asthma has not been studied. In a population-based study of 467 incident adult-onset asthma cases and 613 disease-free controls from South Finland, we analyzed association of 6 tagging SNPs of the IL6 locus with the risk of adult-onset asthma and with atopy. Asthma was clinically diagnosed, and atopy was defined based on Phadiatop test. IL6 SNP rs1800797 associated with the risk of adult-onset asthma in a log additive model, with adjusted odds ratio (aOR) 1.31 (95% confidence interval 1.09-1.57), and especially with the risk of atopic adult-onset asthma when compared with non-atopic controls, aOR 1.46 (95% CI 1.12-1.90). This is the first study to show an association of IL6 with adult-onset asthma, and especially with atopic adult-onset asthma.

Cold weather affects the respiratory epithelium and induces bronchial hyperresponsiveness. We hypothesized that individuals with allergic rhinitis or/and asthma experience cold weather-related functional disability (FD) and exacerbation of health problems (EH) more commonly than individuals without these. This was a population-based study of 7330 adults aged 25–74 years. The determinants of interest, including doctor-diagnosed asthma and allergic rhinitis, and the outcomes, including cold weather-related FD and EH, were measured using a self-administered questionnaire. The prevalences of cold-related FD and EH were 20.3% and 10.3%, respectively. In Poisson regression, the risk of FD increased in relation to both allergic rhinitis (adjusted prevalence ratio (PR) 1.19, 95% CI 1.04–1.37 among men; 1.26, 95% CI 1.08–1.46 among women), asthma (1.29, 0.93–1.80; 1.36, 0.92–2.02, respectively) and their combination (1.16, 0.90–1.50; 1.40, 1.12–1.76, respectively). Also the risk of cold weather-related EH was related to both allergic rhinitis (1.53, 1.15,−2.04 among men; 1.78, 1.43–2.21 among women), asthma (4.28, 2.88–6.36; 3.77, 2.67–5.34, respectively) and their combination (4.02, 2.89–5.59; 4.60, 3.69–5.73, respectively). We provide new evidence that subjects with allergic rhinitis or/and asthma are more susceptible to cold weather-related FD and EH than those without pre-existing respiratory diseases.

Previous studies have provided contradictory evidence on the role of early childhood respiratory infections in the development of asthma and other allergic diseases during childhood. We investigated early-life respiratory infections as predictors of the development of asthma in a 20-year prospective cohort study (the Espoo Cohort Study, 1991-2011). Information on upper respiratory tract infections (URTIs) and lower respiratory tract infections (LRTIs) was collected with a parent-administered baseline questionnaire covering the preceding 12 months (part 1; n = 2,228), and information on LRTIs leading to hospitalization was obtained from the National Hospital Discharge Registry (part 2; n = 2,568). The incidence of asthma was assessed on the basis of 6-year and 20-year follow-up questionnaires. Adjusted hazard ratios were estimated using Cox proportional hazards models. Both URTIs (adjusted hazard ratio (HR) = 1.64, 95% confidence interval (CI): 1.22, 2.19) and LRTIs (adjusted HR = 2.11, 95% CI: 1.48, 3.00) in early childhood were strong predictors of asthma incidence up to young adulthood (ages 20-27 years). A declining age trend was present for both URTIs (P-trend < 0.01) and LRTIs (P-trend < 0.001). In part 2 of our analysis, a significant risk of asthma was found in relation to LRTIs requiring hospitalization (adjusted HR = 1.93, 95% CI: 1.10, 3.38). The results provide new evidence that respiratory tract infections in early life predict the development of asthma through childhood to young adulthood.

Previously those with asthma were often advised to avoid strenuous exercise because of fear for exercise-induced asthmatic reactions, but recent findings suggest many beneficial effects on health related to exercise. We elaborated on the relation between regular exercise and asthma control among adults. This was a population-based cross-sectional Northern Finnish Asthma Study (NoFAS), in which altogether 1922 adult subjects 17-73 years old living in Northern Finland answered the NoFAS questionnaire. The determinant of interest was the total amount of regular exercise during leisure time, measured in hours per week and categorized into no, low (>0≤2h per week), medium (>2 ≤5h), high (>5≤10h) and very high (>10h) exercise categories. The outcome of interest was asthma control, which was assessed based on the Asthma Control Test (ACT). As statistical methods we applied analysis of variance (ANOVA) and Poisson regression. ACT score increased gradually, i.e. asthma control improved, with an increasing amount of exercise from no exercise (mean ACT = 19.4; difference from the reference: -1.57, 95% CI -2.12 to -1.01) to high exercise reference category (mean = 21.0), but was slightly lower (mean = 20.3; -0.64, 95% CI -1.27 to -0.02) in the very high exercise category. Such non-linear relation was present both in women and in men. In conclusion, we provide evidence that moderate to high regular exercise improves asthma control among adults with asthma. Advice about regular exercise should be included as an important part of asthma management for adults.

IntroductionSmoking increases the risk of asthma and reduces lung function among subjects with and without asthma. We assessed the effects of smoking on lung function reflecting both central and small airways among adults with newly onset asthma.MethodsIn a population-based study, 521 (response rate 86%) working-aged adults with clinically defined newly diagnosed asthma answered a questionnaire on personal smoking and other factors potentially influencing lung function, and performed spirometry. We applied multiple linear regression analysis to estimate the relations between smoking and lung function adjusting for confounding.ResultsAmong asthmatics, FEV1 level was reduced significantly, on average 208 mL, related to regular smoking (adjusted effect estimate −0.208, 95% CI −0.355 to −0.061) and 245 mL in relation to former smoking, that is, among those who quit less than a year ago (−0.245, 95% CI −0.485 to −0.004). In contrast, FEV1 was not significantly related to occasional smoking or former smoking among those who quit over a year ago. Forced expiratory flow (FEF) levels (L/s) were also significantly reduced among regular smokers (FEF25–75%: −0.372, 95% CI −0.607 to −0.137; FEF50%: −0.476, 95% CI −0.750 to −0.202). An exposure–response pattern related to both daily smoking rate and lifetime cumulative smoking was seen both among men and women.ConclusionsThis study provides new evidence that among working-aged adults with new asthma, regular smoking and former smoking reduce lung function levels with a dose–response pattern. The lung function parameters applied as outcomes reflect both larger and smaller airways.

Background Asthma subtyping is a complex new field of study. Usually both etiological and outcome factors of asthma have been used simultaneously for subtyping thus making the interpretation of the results difficult. Identification of subtypes of asthma based on questionnaire data only will be useful for both treatment of asthma and for research. Our objective was to identify asthma subtypes that capture both asthma control and severity based on easily accessible variables. Methods We applied latent class analysis for the 1995 adult asthmatics, 692 men and 1303 women, of the Northern Finnish Asthma Study (NoFAS). The classifying variables included use of asthma medication within the last 12 months, St. George’s Respiratory Questionnaire score, and asthma-related healthcare use within the last 12 months. Covariates adjusted for included COPD, allergic rhinitis/allergic eczema, BMI, age and sex. All information was based on self-administered questionnaires. Results We identified four subtypes for women: Controlled, mild asthma (41% of participants); Partly controlled, moderate asthma (24%); Uncontrolled asthma, unknown severity (26%), and Uncontrolled, severe asthma (9%). For men we identified three subtypes: Controlled, mild asthma (31%); Poorly controlled asthma, unknown severity (53%); and Partly controlled, severe asthma (17%). For almost 96% of the subjects this subtyping was accurate. The covariates fitted in the model were based on clinical judgment and were good predictors of class membership. Conclusions Our results show that it is possible to form meaningful and accurate asthma subtypes based on questionnaire data, and that separate classification should be applied for men and women. Electronic supplementary material The online version of this article (doi:10.1186/s12931-017-0508-y) contains supplementary material, which is available to authorized users.

Diurnal variation (DV) affects lung function but the changes are thought to be related to sleep patterns rather than time of day. When diagnosing occupational asthma (OA), serial peak expiratory flow (PEF) measurements are the recommended first line investigation, but could be confounded by shift work.The aim of the study was to investigate the effects of shift work on PEF measurements used for diagnosing OA.PEF records containing more than one shift pattern with ≥ 4 days per shift were identified. OA diagnosis was based on an Oasys-2 score ≥ 2.51 and non-OA on having an alternative clinical diagnosis and Oasys-2 score2.51. The mean area between curves (ABC) score, mean PEF DV and cross-shift PEF changes were calculated for each shift.Records from 123 workers with OA and 69 without OA satisfied inclusion criteria. In the OA group, PEF declined more on afternoon and night shifts than days (P0.001). The ABC score was lower in the OA group on night (P0.05) and afternoon shifts (P0.05) as compared with days, without significant differences in DV. Among those without OA, cross-shift PEF increased more on day shifts (mean + 25 l/min) than afternoon or night shifts (+1 l/min) (P0.001). The sensitivity for the ABC score and DV were good and similar across shifts, but specificity was reduced using DV (DV mean 39%; ABC 98%).PEF responses between work and rest show small differences according to shift type. The ABC score has a high sensitivity and specificity for all shifts; differences in DV have lower specificity.

Although many guidelines recommend regular exercise for adults with asthma, the empirical evidence on the effect of exercise on adult asthma has been inconsistent and there are no previous systematic reviews on this topic. To fill in this gap of knowledge, we synthesized the data on the effects of regular exercise on physical fitness, asthma control and quality of life of adult asthmatics. We performed a Medline search from 1980 through June 2011. In the systematic review we included all clinical trials that provided information on the effects of regular exercise on adult asthma. We conducted meta-analyses of maximal oxygen consumption (VO(2)max) and forced expiratory volume in 1 s (FEV(1)) based on 9 studies. A total of 11 studies were included in the analyses, but only 6 of them had a non-exercising reference group of asthmatics. The meta-analyses of randomized controlled trials showed that regular exercise significantly improved VO(2)max. There was no obvious improvement in lung function measurements. Some individual studies showed evidence of improvement in quality of life and asthma control. Meta-analyses provided evidence that regular physical exercise improves physical fitness of adult asthmatics. The results on effects on lung function were inconclusive. There is insufficient evidence to assess the effects of exercise on asthma control and quality of life.

Machinists are exposed to many sensitizing and irritant substances, but no previous study has assessed the occurrence of clinically verified occupational diseases in an unselected large workforce of machinists. Our aim was to study the occurrence of clinically verified occupational respiratory and skin diseases cross-sectionally in a large sample of machinists in southern Finland.A computer-assisted telephone interview on occupational exposures and health was carried out in a sample of 961 machining workers from 64 metalworking companies. Of these, 757 (79%) answered the interview. A total of 245 subjects reported work-related respiratory or skin symptoms and were invited to clinical examinations; 138 of these underwent a clinical interview and examination by an occupational health physician. On the basis of this examination, 32 subjects were further examined at the Finnish Institute of Occupational Health (FIOH) for occupational skin or respiratory diseases.One case of occupational asthma (OA) and seven cases of occupational dermatoses (OD) were diagnosed, giving a prevalence of 0.13% (95% CI 0-0.39) for OA, and 0.92% (95% CI 0.24-1.16) for OD. The OA was induced by the patient's own MWF. Additional five cases of newly diagnosed non-occupational asthma (0.79%, 95% CI = 0.16-1.42) were detected. No cases of occupational rhinitis or COPD were diagnosed. The dermatoses diagnoses consisted of four cases of allergic contact dermatitis and three cases of irritant contact dermatitis. The most common causes of the ODs were MWFs.This large clinical study of machinists representing metalworking in South Finland showed a prevalence of 0.13% of OA and 0.92% of OD. This relatively low occurrence of occupational diseases may reflect the strict Finnish criteria for the diagnosis of these occupational diseases and the relatively good level of occupational hygiene in machining workshops in Finland. Reported respiratory and skin symptoms were common, and these milder conditions may be linked to irritant rather than sensitizing exposures.

There is inconclusive evidence suggesting a possible association of asthma with increased risk of caries. The authors conducted a systematic review and meta-analysis to synthesize the evidence on the relation between asthma and caries. They performed an Ovid Medline (US National Library of Medicine) database search of literature published from 1950 through May 2010 using the Medical Subject Headings "asthma" and "caries." Summary effect estimates were calculated with fixed- and random-effects models, and determinants of heterogeneity were studied in meta-regression analysis. The meta-analysis was based on 11 articles providing estimates of the effect of asthma on primary dentition and 14 articles on permanent dentition. Summary effect estimates for the relation between asthma and caries from the random-effects models were 2.73 (95% confidence interval: 1.61, 4.64) and 2.04 (95% confidence interval: 1.44, 2.89), respectively. Factors identified as determinants of heterogeneity were geographic region for primary dentition and publication year, sample size, asthma definition, and information on the use of asthma medication for permanent dentition. Evidence from this analysis suggests that asthma doubles the risk of caries in both primary and permanent dentition. Publication bias diagnostics and simulation suggested possible overestimation of the summary odds ratio for permanent dentition but not for primary dentition. Physicians and dentists should recommend preventive measures against caries for persons with asthma.

The authors assessed the relation between exposure to dampness and molds in dwellings and the development of allergic rhinitis in childhood in a 6-year, population-based prospective cohort study of 1,863 children aged 1-7 years at baseline in 1991 (follow-up rate, 77%) from Espoo, Finland. The studied exposures were history of water damage, presence of moisture and visible mold, and perceived mold odor in the home, based on parent-administered questionnaire. A total of 246 (13.2%) children developed physician-diagnosed allergic rhinitis during the study period, resulting in an incidence rate of 440 cases per 10,000 person-years (95% confidence interval (CI): 387, 499). In logistic regression adjusting for confounding, any mold or dampness exposure indicator at baseline (adjusted odds ratio = 1.55, 95% CI: 1.10, 2.18), at follow-up (adjusted odds ratio = 1.62, 95% CI: 1.21, 2.18), or both (adjusted odds ratio = 1.96, 95% CI: 1.29, 2.98) was an important independent determinant of the risk of allergic rhinitis. Of the individual indicators, water damage and moisture on the surfaces were consistent determinants of allergic rhinitis. The results of this cohort study, which assessed exposure before the onset of allergic rhinitis, strengthen considerably the evidence of the role of indoor dampness problems as determinants of allergic rhinitis in children.

The Oasys programme plots serial peak expiratory flow (PEF) measurements and produces scores of the likelihood that the recordings demonstrate occupational asthma. We have previously shown that the area between the mean workday and rest day PEF curves [the area between the curves (ABC) score] has a sensitivity of 69% and specificity of 100% when plotted from waking time using a cut-off score of 15 l/min/h.To investigate the minimum data requirements to maintain the sensitivity and specificity of the ABC score.A total of 196 sets of measurements from workers with occupational asthma confirmed by methods other than serial PEFs and 206 records from occupational and non-occupational asthmatics who were not at work at the time of PEF monitoring were analysed according to their mean number of readings per day. Measurements from work and rest days were sequentially removed separately and the ABC score calculated at each reduction. The sensitivity and specificity of the ABC score (using a cut-off of 15 l/min/h) was calculated for each duration.Two-hourly measurements (approximately 8 readings per day) with eight workdays and three rest days had 68% sensitivity and 91% specificity for occupational asthma diagnosis. As readings decreased toor=4 readings per day,or=15 workdays were required to provide a specificity above 90%.To be sensitive and specific in the diagnosis of occupational asthma, the ABC score requires 2-hourly PEF measurements on eight workdays and three rest days. This is a short assessment period that should improve patient compliance.

Objectives: Potential health effects related to wood dust from the rubber tree, which produces natural rubber latex, have not been previously investigated. The main aim of this study was to investigate the relations of rubber tree dust exposure to respiratory and skin symptoms, asthma and lung function. Methods: A cross-sectional study was conducted among 103 workers (response rate 89%) in a rubber tree furniture factory and 76 office workers (73%) in four factories in Thailand. All participants answered a questionnaire and performed spirometry. Inhalable dust levels were measured in different work areas. Results: Factory workers showed increased risk of wheezing, nasal symptoms and asthma compared to office workers. There was a dose-dependent increase in wheeze and skin symptoms in relation to dust level. Significantly increased risks of nasal symptoms (adj OR 3.67, 95% CI 1.45 to 9.28) and asthma (8.41, 1.06 to 66.60) were detected in the low exposure category. Workers exposed to ethyl cyanoacrylate glue had significantly increased risk of cough, breathlessness and nasal symptoms. There was dose-dependent reduction in spirometric lung function with wood dust level. Conclusions: This study provides new evidence that workers exposed to wood dust from the rubber tree experience increased risk of nasal symptoms, wheeze, asthma and skin symptoms and have reduced spirometric lung function. Exposure to cyanoacrylate is related to significantly increased respiratory symptoms. Results suggest that the furniture industry using rubber tree wood should implement appropriate exposure control measures to reduce wood dust exposure and cyanoacrylate glue exposure to protect their employees.

Summary Objectives There is evidence suggesting that secondhand smoke (SHS) exposure is causally linked to adverse respiratory effects. We examined the relations between the exposure to SHS and radiological signs in chest high-resolution computed tomography (HRCT). Methods Asbestos-exposed workers ( n =633) were imaged with HRCT, primarily to investigate potential occupational lung disease. After excluding current smokers, the study population included 361 ex- and 141 never-smokers. They answered a questionnaire on occupational exposures, smoking habits and SHS exposure. HRCT images were assessed for emphysema, ground-glass, irregular/linear and rounded opacities, honeycombing and several other signs. Regression analyses were adjusted for asbestos exposure, ex-smoking, age, body mass index and potential reader effect. Results Due to missing data the multivariate analyses were restricted to 310 participants aged 47.5–87.0 years. Their lifetime SHS exposure ranged between 0 and 193.5 pack-years (mean 23.5), and exposure in the past 12 months 0–30 packs (0.43). Total ( B =0.005, 95% confidence intervals (95% CI) 0.002–0.008, p =0.000) and workplace ( B =0.006, 95% CI 0.003–0.009, p =0.001) cumulative SHS exposures were significantly related to ground-glass opacities. Total SHS exposure in the last 12 months ( B =0.027, 95% CI 0.000–0.054, p =0.048) and workplace exposure ( B =0.027, 95% CI 0.000–0.054, p =0.048) were also significantly related to ground-glass opacities. Positive effects of SHS were also detected on irregular/linear opacities. Conclusions SHS exposure in the last 12 months and over lifetime significantly increases ground-glass opacity in HRCT, suggesting an early or subclinical desquamative interstitial pneumonia/respiratory bronchiolitis. This study further supports that SHS has adverse effects on the lungs that can be detected by X-ray methods.

Ingestion of milk powder is a known cause of allergies in children, but the risks to respiratory health from exposure to inhaled milk powder have not been studied previously. The aim of the present study was to assess the effects of occupational exposures in a milk powder factory on respiratory symptoms and lung function. A cross-sectional study was conducted on 167 milk powder factory workers (response rate 77%) and 76 office workers (73%) from four factories in Thailand. All participants answered a questionnaire and performed spirometry. Measurements of concentrations of dust were used to give additional information on exposures. Mean respirable dust concentrations in the factory were 0.02–2.18 mg·m −3 . The risk of breathlessness and nasal symptoms were significantly increased in production and packing staff. The risk of skin symptoms was significantly increased in those adding vitamin mixture to milk powder. Factory workers showed significantly lower forced expiratory volume in one second measured as percentage of predicted value. The present study provides new evidence that workers exposed to milk powder by inhalation are at an increased risk of nasal symptoms, wheezing and breathlessness, and exhibit reduced spirometric lung function, even at relatively low air concentrations of milk dust.

Occupational asthma remains a common disease in the UK with up to 3000 new cases diagnosed each year. The Health and Safety Executive (HSE) estimates the cost to our society to be over £1.1 billion for each 10-year period.1 In October 2001 the Health and Safety Commission agreed a package of measures aimed at reducing the incidence of asthma caused by exposure to substances in the workplace by 30% by 2010. Key to this aim are primary prevention by proper risk assessment and exposure control, together with secondary prevention to ensure reduction in the delay between the development of allergic symptoms at work (normally nasal or respiratory) and appropriate advice to the affected worker and workplace. Conservative estimates suggest that one in 10 cases of adult onset asthma relate directly to sensitisation in the workplace,2 with a smaller subset of workers with acute irritant induced asthma. The latter—formerly termed reactive airway dysfunction syndrome (RADS)—relates to asthma caused by exposure to high levels of airborne irritants. The prognosis of individuals with occupational asthma is better if they are removed from exposure quickly, particularly within a year of first symptoms.3–5 However, removing individuals often leads to unemployment. If the diagnosis of occupational asthma is incorrect, advising individuals whose asthma is not caused by work to be removed from exposure may have unnecessary financial and social consequences. The intent of this article is not to document the entire current evidence base related to occupational asthma, as the British Occupational Health Research Foundation (BOHRF) recently completed such an evidence review.7 The key points of this article are summarised in box …

BACKGROUND Trends of occupational asthma (OA) differ between regions depending on local industries, provisions for health and safety at the workplace and the availability of a reporting scheme to help in data collection and interpretation. AIM To assess trends in OA in an industrialized part of the UK over a 15-year period. METHODS Occupational and chest physicians in the West Midlands were invited to submit details of newly diagnosed cases with OA. Data were then transferred to the regional centre for occupational lung diseases for analysis. RESULTS A total of 1461 cases were reported to the scheme. Sixty-eight per cent were males with mean (standard deviation) age of 44 (12) years. The annual incidence of OA was 42 per million of working population (95% CI = 37-45). OA was most frequently reported in welders (9%) and health care-related professions (9%) while < 1% of cases were reported in farmers. Isocyanates were the commonest offending agents responsible for 21% of reports followed by metal working fluids (MWFs) (11%), adhesives (7%), chrome (7%), latex (6%) and glutaraldehyde (6%). Flour was suspected in 5% of cases while laboratory animals only in 1%. CONCLUSIONS Our data confirm a high annual incidence of OA in this part of the UK. MWFs are an emerging problem, while isocyanates remain the commonest cause. Incidence remained at a fairly stable background level with many small and a few large epidemics superimposed. Schemes like Midland Thoracic Society's Rare Respiratory Disease Registry Surveillance Scheme of Occupational Asthma could help in identifying outbreaks by linking cases at the workplace.

Early-life respiratory tract infections (RTIs) and dental caries are among the most common infectious diseases worldwide. The relations between early RTIs and development of caries in permanent teeth have not been studied earlier. We assessed childhood RTIs as potential predictors of caries in young adulthood in a 20-year prospective population-based cohort study (The Espoo Cohort Study). Information on lower respiratory tract infections (LRTIs) that had required hospitalization was retrieved from the National Hospital Discharge Registry (n = 1623). Additional information on LRTIs and upper RTIs (URTIs) was assessed based on the questionnaire reports that covered the preceding 12 months. Caries was measured as the number of teeth with fillings (i.e. filled teeth, FT) reported in the 20-year follow-up questionnaire. The absolute and relative excess numbers of FT were estimated applying negative binomial regression. The mean number of FT in young adulthood was 1.4 greater among subjects who had experienced LRTIs requiring hospitalization before the age of 2 years (SD 4.8) compared to those without any such infections (SD 3.4), and the adjusted relative excess number of FT was 1.5 (95% CI 1.0-2.2). LRTIs up to 7 years were associated with an absolute increase of 0.9 in the mean FT number, the adjusted relative excess being 1.3 (1.0-1.8). Also the questionnaire-based LRTIs (adjusted relative excess 1.3; 95% CI 0.9-1.8) and URTIs (adjusted relative excess 1.4, 1.0-1.8) before the age of 2 years predicted higher occurrence of FT. Findings suggest that early RTIs have a role in the development of dental caries in permanent teeth.

Objectives: To assess the relation between exposure to carbonless copy paper (CCP), paper dust, and fumes from photocopiers and printers (FPP), and the occurrence of sick building syndrome (SBS)-related symptoms, chronic respiratory symptoms and respiratory infections. Methods: A population-based cross-sectional study with a random sample of 1016 adults, 21–63 years old, living in Pirkanmaa District in South Finland was conducted. This study focused on 342 office workers classified as professionals, clerks or administrative personnel according to their current occupation by the International Standard Classification of Occupations-88. They answered a questionnaire about personal information, health, smoking, occupation, and exposures in the work environment and at home. Results: In logistic regression analyses adjusting for age, sex and a set of other confounders, all three exposures were related to a significantly increased risk of general symptoms (headache and fatigue). Exposure to paper dust and to FPP was associated with upper respiratory and skin symptoms, breathlessness, tonsillitis and middle ear infections. Exposure to CCP increased the risk of eye symptoms, chronic bronchitis and breathlessness. It was also associated with increased occurrence of sinus and middle ear infections and diarrhoea. A dose–response relations was observed between the number of exposures and occurrence of headache. The risk of tonsillitis and sinus infections also increased with increasing number of exposures. All chronic respiratory symptoms, apart from cough, were increased in the highest exposure category (including all three exposures). Conclusions: This study provides new evidence that exposure to paper dust and to FPP is related to the risk of SBS symptoms, breathlessness and upper respiratory infections. It strengthens the evidence that exposure to CCP increases the risk of eye symptoms, general symptoms, chronic respiratory symptoms and some respiratory infections. Reduction of these exposures could improve the health of office workers.

The season of birth has been suggested to influence the development of some diseases, but its role in lung fibrosis seems to not have been studied previously. The aim of this study was to investigate the relation between the season of birth and fibrotic abnormalities as detected radiologically in high-resolution computed tomography (HRCT) among workers exposed to asbestos. The HRCT examination was performed on 528 study subjects. Multiple ordinal regression analysis adjusting for covariates was used to study the relations between birth month or season and radiological fibrosis signs. Subjects born in autumn or winter had more extensive fibrotic changes than those born in spring or summer. This applied to all fibrotic changes, apart from subpleural nodules, but only the overall fibrosis score, septal lines, and honeycombing showed statistically significantly higher values in comparison to spring births. The highest scores were detected among those born in autumn and winter months (September-February). These results suggest that there are differences in fibrotic radiological abnormalities according to the season of birth in adults exposed to asbestos. Several hypotheses could explain the observed findings, including the effects of early respiratory infections, cold temperature, and differences in air pollution levels, as well as some metabolic and hormonal effects.

Enhancers and promoters commonly occur in accessible chromatin characterized by depleted nucleosome contact; however, it is unclear how chromatin accessibility is governed. We show that log-additive cis-acting DNA sequence features can predict chromatin accessibility at high spatial resolution. We develop a new type of high-dimensional machine learning model, the Synergistic Chromatin Model (SCM), which when trained with DNase-seq data for a cell type is capable of predicting expected read counts of genome-wide chromatin accessibility at every base from DNA sequence alone, with the highest accuracy at hypersensitive sites shared across cell types. We confirm that a SCM accurately predicts chromatin accessibility for thousands of synthetic DNA sequences using a novel CRISPR-based method of highly efficient site-specific DNA library integration. SCMs are directly interpretable and reveal that a logic based on local, nonspecific synergistic effects, largely among pioneer TFs, is sufficient to predict a large fraction of cellular chromatin accessibility in a wide variety of cell types., National Institutes of Health (U.S.) (Grants 5UL1DE019581, RL1DE019021, 1K01DK101684-01, 1U01HG007037, and 5P01NS055923)

Background In the northern hemisphere people are exposed recurrently to cold air and asthmatics experience more respiratory symptoms. We hypothesized that subjects with poor asthma control are more prone to experience cold weather-related respiratory symptoms than those with good asthma control. Methods A population-based cross-sectional study of 1995 adult asthmatics (response rate 40.4%) living in the Northern Finland was conducted using a questionnaire where cold weather-related respiratory symptoms as well as questions related to asthma control were inquired. The Asthma Control Test (ACT) was defined based on five questions (disadvantage and occurrence of asthma symptoms, waking up because of asthma symptoms, use of rescue medication and self-assessment of asthma control during the past 4 weeks), and was divided into quartiles. Results Cold weather-related respiratory symptoms were more frequent among asthmatics with poorly controlled asthma (ACT Q1 vs. ACT Q4); adjusted prevalence ratio (PR) for shortness of breath (men 1.47, 95% confidence interval 1.22–1.77; women 1.18, 1.07–1.30), cough (men 1.10, 0.91–1.34; women 1.18, 1.08–1.30), wheezing (men 1.91, 1.31–2.78; women 1.48, 1.17–1.87), phlegm production (men 1.51, 1.06–2.14; women 1.62, 1.27–2.08) and chest pain (men 4.47, 1.89–10.56; women 2.60, 1.64–4.12). The relations between asthma control and symptom occurrence seemed stronger among smokers than never smokers and subjects with body mass index (BMI) below and above 25–30. Conclusions Our study provides new evidence that subjects whose asthma is poorly controlled are more prone to experience cold weather-related respiratory symptoms and even a slight worsening of asthma control increases symptom prevalences.

Family history of asthma and other allergic diseases have been linked to the risk of childhood asthma previously, but little is known about their effect on the age-of-onset and persistency of asthma until young adulthood.We assessed the effect of the family history of asthma and allergic diseases on persistent vs. transient, and early- vs. late-onset persistent asthma in The Espoo Cohort Study 1991-2011, a population-based cohort study of 1623 subjects (follow-up rate 63.2%). The determinants were any family history (any parent or sibling); maternal; paternal; siblings only; parents only; and both siblings and parents. Analyses were conducted separately for asthma and allergic diseases while taking the other disease into account as a confounding factor. The outcomes were persistent, transient, early-onset persistent (13 years) and late-onset persistent asthma. Adjusted risk ratios (RR) were calculated applying Poisson regression. Q-statistics were used to assess heterogeneity between RRs.Family history was associated with the different subtypes but the magnitude of effect varied quantitatively. Any family history of asthma was a stronger determinant of persistent (adjusted RR = 2.82, 95% CI 1.99-4.00) than transient asthma (1.65, 1.03-2.65) (heterogeneity: P = 0.07) and on early-onset than late-onset persistent asthma. Also any family history of allergic diseases was a stronger determinant of persistent and early-onset asthma. The impact of paternal asthma continued to young adulthood (early-onset: 3.33, 1.57-7.06 vs. late-onset 2.04, 0.75-5.52) while the influence of maternal asthma decreased with age (Early-onset 3.94, 2.11-7.36 vs. Late-onset 0.88, 0.28-2.81). Paternal allergic diseases did not follow the pattern of paternal asthma, since they showed no association with late-onset asthma. Also the effect estimates for other subtypes were lower than in other hereditary groups (persistent 1.29, 0.75-2.22 vs. transient 1.20, 0.67-2.15 and early-onset 1.86, 0.95-3.64 vs. late-onset 0.64, 0.22-1.80).Family history of asthma and allergic diseases are strong determinants of asthma, but the magnitude of effect varies according to the hereditary group so that some subtypes have a stronger hereditary component, and others may be more strongly related to environmental exposures. Our results provide useful information for assessing the prognosis of asthma based on a thorough family history.

Asthma is a multifactorial airway disease that arises from a relatively common genetic background interphased with exposures to allergens and airborne irritants. The rapid rise in asthma over the past three decades in Western societies has been attributed to numerous diverse factors, including increased awareness of the disease, altered lifestyle and activity patterns, and ill-defined changes in environmental exposures. It is well accepted that persons with asthma are more sensitive than persons without asthma to air pollutants such as cigarette smoke, traffic emissions, and photochemical smog components. It has also been demonstrated that exposure to a mix of allergens and irritants can at times promote the development phase (induction) of the disease. Experimental evidence suggests that complex organic molecules from diesel exhaust may act as allergic adjuvants through the production of oxidative stress in airway cells. It also seems that climate change is increasing the abundance of aeroallergens such as pollen, which may result in greater incidence or severity of allergic diseases. In this review we illustrate how environmental tobacco smoke, outdoor air pollution, and climate change may act as environmental risk factors for the development of asthma and provide mechanistic explanations for how some of these effects can occur.

OBJECTIVES Despite a heavy burden of HIV/AIDS and other blood borne infections, few studies have investigated needle stick injuries in sub-Saharan Africa. We conducted a cross-sectional study at Mulago national referral hospital in Kampala, Uganda, to assess the occurrence and risk factors of needle stick injuries among nurses and midwives. METHODS A total of 526 nurses and midwives involved in the direct day-to-day management of patients answered a questionnaire inquiring about occurrence of needle stick injuries and about potential predictors, including work experience, work load, working habits, training, and risk behaviour. RESULTS A 57% of the nurses and midwives had experienced at least one needle stick injury in the last year. Only 18% had not experienced any such injury in their entire career. The rate of needle stick injuries was 4.2 per person-year. Multiple logistic regression analysis showed that the most important risk factor for needle stick injuries was lack of training on such injuries (OR 5.72, 95% CI 3.41-9.62). Other important risk factors included working for more than 40 h/week (OR 1.90, 95% CI 1.20-3.31), recapping needles most of the time (OR 1.78, 95% CI 1.11-2.86), and not using gloves when handling needles (OR 1.91, 95% CI 1.10-3.32). CONCLUSIONS The study showed a high rate of needle stick injuries among nurses and midwives working in Uganda. The strongest predictor for needle stick injuries was lack of training. Other important risk factors were related to long working hours, working habits, and experience.

The present study describes salivary cotinine levels and their relationship to cigarettes smoked per day in Mexican smokers. Using a sampling strategy based on the number of cigarettes per day, we recruited 1,222 smokers from Mexico City and the state of Morelos in Mexico during 1999. Smoking behaviors and other factors known to affect nicotine intake and cotinine level were identified in an interview using a standardized questionnaire. Salivary cotinine was measured by capillary gas chromatography with nitrogen-phosphorus detection. We used generalized additive models to describe the relationship between salivary cotinine levels and variables of interest. The mean age of the population was 39.7 years (SD=15.6 years), with a mean cotinine level of 194.7 ng/ml (SD=134.8; range=10.1-767). Participants smoked a mean of 15.5 cigarettes per day (SD=11.3). Salivary cotinine and cigarettes smoked per day were positively related, although the association was not linear, flattening above 20 cigarettes per day. After adjusting for cigarettes per day, we found that significant predictors of cotinine levels included age, body mass index, cigarette producer, and smoking behavior variables. These results may have implications for dosing with nicotine medications to aid smoking cessation in Mexican smokers and suggest that whether the cigarette is labeled light or regular has no relationship to nicotine dose from smoking cigarettes.

We studied the effects of age, body mass index (BMI) and some common laboratory test results on several pulmonary CT/HRCT signs. Five hundred twenty-eight construction workers (age 38-80, mean 63 years) were imaged with spiral and high resolution CT. Images were scored by three radiologists for solitary pulmonary nodules, signs indicative of fibrosis and emphysema, ground glass opacities, bronchial wall thickness and bronchiectasis. Multivariate statistical analyses were adjusted for smoking and asbestos exposure. Increasing age, blood haemoglobin value and erythrocyte sedimentation rate correlated positively with several HRCT signs. Increasing BMI was associated with a decrease in several signs, especially parenchymal bands, honeycombing, all kinds of emphysema and bronchiectasis. The latter finding might be due to the suboptimal image quality in obese individuals, which may cause suspicious findings to be overlooked. Background data, including patient's age and body constitution, should be considered when CT/HRCT images are interpreted.

Objectives. The authors assessed the effects of environmental tobacco smoke (ETS) on the development of asthma in adults. Methods. In the Pirkanmaa district of South Finland, all 21- to 63-year-old adults with new cases of asthma diagnosed during a 2.5-year period (n = 521 case patients, out of 441 000 inhabitants) and a random sample of control subjects from the source population (932 control subjects) participated in a population-based incident case–control study. Results. Risk of asthma was related to workplace ETS exposure (adjusted odds ratio [OR] = 2.16; 95% confidence interval [CI] = 1.26, 3.72) and home exposure (OR = 4.77; 95% CI = 1.29, 17.7) in the past year. Cumulative ETS exposure over a lifetime at work and at home increased the risk. Conclusions. This study indicates for the first time that both cumulative lifetime and recent ETS exposures increase the risk of adult-onset asthma.

This study examined the effects of smoking on the findings in chest computed tomography (CT) in 587 asbestos-exposed construction workers (11 females, 576 males, mean age 62 yrs; 18 never-smokers, 406 exsmokers and 163 current smokers). The workers were imaged with spiral CT and high-resolution CT. A total of 13 radiological signs were scored by three radiologists independently. The workers' medical data, smoking habits and occupational exposures were collected at an interview. The effects of smoking status and smoked pack-yrs (0-87.5) on the CT signs were studied using multivariate analysis adjusted for confounding factors. Smoking increased all emphysema signs and contributed to bronchial wall thickening. Smoking was negatively associated with curvilinear and septal lines as well as with parenchymal bands. In persons who had smoked

Background Identifying factors that affect cotinine levels in smokers may be useful for smoking cessation programs. Our aims were to characterize the distribution of salivary cotinine levels in Chinese smokers and to investigate factors that influence cotinine concentrations. Methods In a cross-sectional study, 600 Chinese adult smokers answered a questionnaire on smoking habits and provided a saliva sample for cotinine analysis. Modification of the relation between number of cigarettes smoked and cotinine concentration by individual characteristics, smoking behavior, and type of tobacco was evaluated. Results Quadratic model provided the best fit for the relation between number of cigarettes smoked in the previous 24 hours and salivary cotinine concentration. Among those smoking up to 20 cigarettes, the median cotinine concentration was higher among younger subjects, those smoking cigarettes without filter and regular rather than light cigarettes, and those inhaling frequently and deeply. Such trends were not observed among heavier smokers. The increase in cotinine per cigarette tended to be larger in those with lower median cotinine level. Conclusions Our findings show that smoking behavior-related factors modify the relation between number of cigarettes smoked and salivary cotinine concentration. This suggests that smokers may regulate their smoking behavior to achieve a certain optimum nicotine level.

Irritant-induced asthma is a rare disease, usually being caused by an accidental or other exceptionally strong exposure to substances irritating the respiratory passages. High-dose inhaled corticosteroid medication is immediately started at the emergency call service. If severe exposure is suspected, it is important to monitor the patient at least for a couple of days in hospital. Immediately after the acute stage diagnostic investigations are carried out, including a metacholine or histamine challenge test, since demonstration of airway hyperreactivity is of diagnostic and prognostic significance. The asthma may remain permanent.

SUMMARY Immunoglobulin G (IgG) antibodies against microbes related to indoor dampness problems have been used as potential biomarkers of fungal exposure in clinical investigations. There is limited information on their relation to asthma. We conducted a population-based incident case–control study to assess the risk of asthma in relation to specific IgG antibodies to eight dampness-related microbes: Aspergillus fumigatus, A. versicolor, Cladosporium cladosporioides, Fusarium oxysporum, Sporobolomyces salmonicolor, Stachybotrys chartarum, Streptomyces albus and Trichoderma citrinoviride. We recruited systematically all new cases of asthma during a 2·5-year study period and randomly selected controls from a source population of adults 21–63 years of age living in the Pirkanmaa Hospital District, South Finland. The clinically diagnosed case series consisted of 521 adults with newly diagnosed asthma and the control series of 932 controls selected randomly from the source population. IgG antibodies were analysed with ELISA. An increased risk of developing asthma in adulthood was significantly related to IgG antibodies to T. citrinoviride, but not to the other moulds. There was no evidence of a dose–response relation between the IgG antibody level and the risk of asthma. T. citrinoviride may play a role in the aetiology of adult-onset asthma or serve as an indicator of other causal factors.

The aims of this article are to synthesize the evidence on health effects of environmental tobacco smoke (ETS) in the elderly and to discuss questions for future research. Health effects are divided into aetiological and prognostic studies. There is convincing evidence that ETS causes lung cancer and coronary heart disease, both of which are diseases of the elderly. Several cross-sectional studies show increased occurrence of chronic respiratory symptoms and deficits in ventilatory lung function in relation to ETS exposure at home and/or at work. A limited number of studies have found significant relations between ETS exposure and asthma, chronic obstructive pulmonary disease (COPD), pneumococcal infections and stroke in the elderly. Longitudinal studies are needed before any definite conclusions can be made concerning ETS and noncarcinogenic respiratory diseases in the elderly. The potential role of environmental tobacco smoke exposure as a prognostic factor determining development of a pre-existing respiratory or heart disease is an important new area for research.

The Helsinki Office Environment Study, a population-based cross-sectional study was carried out in Finland in 1991 among 2,678 workers in 41 randomly selected office buildings. The aim was to evaluate the relations between work with office equipment and supplies and the occurrence of eye, nasopharyngeal, skin, and general symptoms (often denoted as sick building syndrome (SBS)), chronic respiratory symptoms, and respiratory infections. Work with self-copying paper was significantly related to weekly work-related eye, nasopharyngeal, and skin symptoms, headache and lethargy, as well as to the occurrence of wheezing, cough, mucus production, sinusitis, and acute bronchitis. Photocopying was related to nasal irritation, and video display terminal work to eye symptoms, headache, and lethargy.

This article addresses concepts of environmental tobacco smoke (ETS) exposure assessment relevant for health risk assessment based on human studies. We present issues that should be considered when selecting a method for ETS exposure assessment for the purposes of health risk assessment and review data on ETS exposure levels in the workplace and in home environments. Two types of estimates are needed for a quantitative risk assessment of the health effects resulting from occupational ETS exposure: (italic)a(/italic)) an unbiased estimate of the exposure-effect (or dose-response) relation between ETS and the health effect of interest, and (italic)b(/italic)) estimates of the distribution of ETS exposure in different workplaces. By combining the estimated exposure-effect relation with information on exposure distribution for a population of interest, we can calculate the proportions of disease cases attributable to occupational ETS exposure as well as the excess number of cases due to specified exposure conditions. Several dimensions of the exposure profile should be considered when assessing ETS exposure for estimating the exposure-effect relation, including the magnitude of exposure and the biologically relevant time specificity of exposure. The magnitude of exposure is determined by the ETS source strength, environmental factors modifying concentrations, and duration of exposure. Time specificity considerations include the latency period for each health outcome of interest, the time-exposure profile relevant for different disease mechanisms, and the sensitive age period with regard to health effects. The most appropriate indicator of ETS exposure depends on these factors and on the time period that can be assessed with different methods. Images Figure 1 Figure 3 Figure 4