Occupational noise exposure and risk of incident stroke: a pooled study of five Scandinavian cohorts.

OBJECTIVES: To investigate the association between occupational noise exposure and stroke incidence in a pooled study of five Scandinavian cohorts (NordSOUND). METHODS: We pooled and harmonised data from five Scandinavian cohorts resulting in 78 389 participants. We obtained job data from national registries or questionnaires and recoded these to match a job-exposure matrix developed in Sweden, which specified the annual average daily noise exposure in five exposure classes (LAeq8h): <70, 70-74, 75-79, 80-84, ≥85 dB(A). We identified residential address history and estimated 1-year average road traffic noise at baseline. Using national patient and mortality registers, we identified 7777 stroke cases with a median follow-up of 20.2 years. Analyses were conducted using Cox proportional hazards models adjusting for individual and area-level potential confounders. RESULTS: Exposure to occupational noise at baseline was not associated with overall stroke in the fully adjusted models. For ischaemic stroke, occupational noise was associated with HRs (95% CI) of 1.08 (0.98 to 1.20), 1.09 (0.97 to 1.24) and 1.06 (0.92 to 1.21) in the 75-79, 80-84 and ≥85 dB(A) exposure groups, compared with <70 dB(A), respectively. In subanalyses using time-varying occupational noise exposure, we observed an indication of higher stroke risk among the most exposed (≥85 dB(A)), particularly when restricting analyses to people exposed to occupational noise within the last year (HR: 1.27; 95% CI: 0.99 to 1.63). CONCLUSIONS: We found no association between occupational noise and risk of overall stroke after adjustment for confounders. However, the non-significantly increased risk of ischaemic stroke warrants further investigation.

Occupational stress and pregnancy-related hypertension and diabetes: Results from a nationwide prospective cohort.

OBJECTIVES: Using a large, national, prospective cohort, while adjusting for other work exposures, this study aims to investigate whether exposure to occupational stress during pregnancy is associated with hypertensive disorders of pregnancy (HDP) and gestational diabetes. METHODS: Our cohort consisted of 1 102 230 singleton births between 1994-2014 in Sweden, based on high-quality register data of Swedish pregnancies. Exposure to occupational stress was obtained from a job exposure matrix (JEM) constructed from 12 questions pertaining to the psychosocial work environment from the 1997-2013 cycles of Swedish Work Environment Survey, including approximately 75 000 individuals. We utilized the decision authority, demands, and social support indices. Decision authority and demands were combined to categorize occupations into low, active, passive, and high strain work. We estimated relative risks (RR) and adjusted for relevant confounders, such as age, smoking and other work exposures. RESULTS: Occupations with lower levels of decision authority were associated with increased risks of 12-23% for HDP and preeclampsia and 36-58% for gestational diabetes compared to occupations with the highest levels of decision authority. Passive occupations had increased risks of 10% for HDP and preeclampsia and 15% for gestational diabetes when compared to low strain jobs. No significant associations were found for high strain occupations. CONCLUSIONS: As a whole, occupational stress was not consistently associated with pregnancy outcomes in our study. However, decision authority was associated with an increased risk for pregnancy-related complications. Further studies should investigate whether improvements in working conditions can help decrease these risks.

Working life, health and well-being of parents: a joint effort to uncover hidden treasures in European birth cohorts.

OBJECTIVE: Birth cohorts collect valuable and under-utilized information on employment and health of parents before and during pregnancy, at birth, and sometimes after birth. In this discussion paper, we examine how these data could be exploited to study the complex relationships and interactions between parenthood, work, and health among parents themselves. METHODS: Using a web-based database of birth cohorts, we summarize information on maternal employment and health conditions and other potentially related variables in cohorts spread throughout Europe. This provided information on what data are available and could be used in future studies, and what was missing if specific questions are to be addressed, exploiting the opportunity to explore work-health associations across heterogenous geographical and social contexts. RESULTS: We highlight the many potentialities provided by birth cohorts and identify gaps that need to be addressed to adopt a life-course approach and investigate topics specific to the peri-pregnancy period, such as psychosocial aspects. We address the technical difficulties implied by data harmonization and the ethical challenges related to the repurposing of data, and provide scientific, ecological and economic arguments in favor of improving the value of data already available as a result of a serious investment in human and material resources. CONCLUSIONS: There is a hidden treasure in birth cohorts that deserves to be brought out to study the relationships between employment and health among working parents in a time when the boundaries between work and life are being stretched more than ever before.

Occupational exposure to noise in relation to pregnancy-related hypertensive disorders and diabetes.

Objectives Exposure to environmental noise has been associated with an increased risk of cardiovascular diseases and diabetes, but evidence for occupational noise is limited and conflicting, especially related to pregnancy outcomes. This study aimed to evaluate the association of occupational noise exposure with hypertensive disorders of pregnancy (HDP) and gestational diabetes. Methods Our population-based cohort study utilized data on 1 109 516 singletons born to working mothers in Sweden between 1994-2014 from the Medical Birth Register and the Longitudinal Integration Database for Health Insurance and Labor Market Studies. Noise exposure came from a job exposure matrix (JEM) in five categories <70, 70-74, 75-80, 80-85, >85 dB(A). Relative risks (RR), adjusted for confounders and other job exposures, were calculated by modified Poisson regressions for the full sample and a subsample of first-time mothers reporting full-time work. Results Exposure to 80-85 dB(A) of noise was associated with an increased risk of all HDP [RR 1.12, 95% confidence interval (CI) 1.05-1.18] and preeclampsia alone (RR 1.14, 95% CI 1.07-1.22) in the full sample. Results were similar for first-pregnancy, full-time workers. Exposure to >85 dB(A) of noise was also associated with an increased risk of gestational diabetes (RR 1.57, 95% CI 1.10-2.24) in the analysis restricted to first-time mothers working full-time. Conclusion In this study, exposure to noise was associated with an increased risk for HDP and gestational diabetes, particularly in first-time mothers who work full-time. Further research is needed to confirm findings and identify the role of hearing protection on this association so prevention policies can be implemented.

Persistent emotional distress after a first-time myocardial infarction and its association to late cardiovascular and non-cardiovascular mortality.

BACKGROUND: Patients with symptoms of depression and/or anxiety - emotional distress - after a myocardial infarction (MI) have been shown to have worse prognosis and increased healthcare costs. However, whether specific subgroups of patients with emotional distress are more vulnerable is less well established. The purpose of this study was to identify the association between different patterns of emotional distress over time with late cardiovascular and non-cardiovascular mortality among first-MI patients aged <75 years in Sweden. METHODS: We utilized data on 57,602 consecutive patients with a first-time MI from the national SWEDEHEART registers. Emotional distress was assessed using the anxiety/depression dimension of the European Quality of Life Five Dimensions questionnaire two and 12 months after the MI, combined into persistent (emotional distress at both time-points), remittent (emotional distress at the first follow-up only), new (emotional distress at the second-follow up only) or no distress. Data on cardiovascular and non-cardiovascular mortality were obtained until the study end-time. We used multiple imputation to create complete datasets and adjusted Cox proportional hazards models to estimate hazard ratios. RESULTS: Patients with persistent emotional distress were more likely to die from cardiovascular (hazard ratio: 1.46, 95% confidence interval: 1.16, 1.84) and non-cardiovascular causes (hazard ratio: 1.54, 95% confidence interval: 1.30, 1.82) than those with no distress. Those with remittent emotional distress were not statistically significantly more likely to die from any cause than those without emotional distress. DISCUSSION: Among patients who survive 12 months, persistent, but not remittent, emotional distress was associated with increased cardiovascular and non-cardiovascular mortality. This indicates a need to identify subgroups of individuals with emotional distress who may benefit from further assessment and specific treatment.

Factors associated with emotional distress in patients with myocardial infarction: Results from the SWEDEHEART registry.

Background Emotional distress, symptoms of depression and anxiety, is common among patients after a myocardial infarction (MI), and is associated with an increased risk of cardiovascular morbidity. Real world population data on factors associated with emotional distress in MI patients are scarce. The aim was to determine factors associated with incident emotional distress two and 12 months post MI respectively, and with persistent emotional distress, versus remittent, in patients <75 years old. Design This was a registry-based observational study. Methods Data from the national SWEDEHEART registry on 27,267 consecutive patients with a first-time MI, followed up at two and 12 months post MI ( n = 22,911), were included in the analyses. Emotional distress was assessed with the EuroQol-5D questionnaire. Several candidate sociodemographic and clinical factors were analysed for their association with emotional distress in multivariate models. Results Symptoms of emotional distress were prevalent in 38% and 33% at two and 12 months post MI respectively. At both time-points, previous depression and/or anxiety, readmission for new cardiovascular event, female gender, younger age, born outside the neighbouring Nordic countries, smoking and being neither employed nor retired showed the strongest associations with emotional distress. Other factors related to medical history, the MI and its care or were only modestly associated with emotional distress. Persistent emotional distress was associated with younger age, female gender, smoking and being born outside of the Nordic countries. Conclusion Previous depression/anxiety, female gender, younger age, smoking, born outside of the Nordic countries, neither employed nor retired and readmission due to cardiovascular events were strongly associated with emotional distress post MI. These factors may be of relevance in tailoring rehabilitation programmes.

Young adulthood cognitive ability predicts statin adherence in middle-aged men after first myocardial infarction: A Swedish National Registry study.

Background Cognitive ability (CA) is positively related to later health, health literacy, health behaviours and longevity. Accordingly, a lower CA is expected to be associated with poorer adherence to medication. We investigated the long-term role of CA in adherence to prescribed statins in male patients after a first myocardial infarction (MI). Methods CA was estimated at 18-20 years of age from Military Conscript Register data for first MI male patients (≤60 years) and was related to the one- and two-year post-MI statin adherence on average 30 years later. Background and clinical data were retrieved through register linkage with the unselected national quality register SWEDEHEART for acute coronary events (Register of Information and Knowledge about Swedish Heart Intensive Care Admissions) and secondary prevention (Secondary Prevention after Heart Intensive Care Admission). Previous and present statin prescription data were obtained from the Prescribed Drug Register and adherence was calculated as ≥80% of prescribed dispensations assuming standard dosage. Logistic regression was used to estimate crude and adjusted associations. The primary analyses used 2613 complete cases and imputing incomplete cases rendered a sample of 4061 cases for use in secondary (replicated) analyses. Results One standard deviation increase in CA was positively associated with both one-year (OR 1.15 (CI 1.01-1.31), P < 0.05) and two-year (OR 1.14 (CI 1.02-1.27), P < 0.05) adherence to prescribed statins. Only smoking attenuated the CA-adherence association after adjustment for a range of > 20 covariates. Imputed and complete case analyses yielded very similar results. Conclusions CA estimated on average 30 years earlier in young adulthood is a risk indicator for statin adherence in first MI male patients aged ≤60 years. Future research should include older and female patients and more socioeconomic variables.

Status and determinants of individual actions to reduce health impacts of air pollution in US adults.

Although regulation of emissions is the primary strategy to reduce air pollution-related morbidity, individual-level interventions are also helpful in mitigating health impacts. We used data from 2007-2008 National Health and Nutrition Examination Survey to study the prevalence of individual-level action among the US adult population if informed of air pollution, and to see if this differed by demographic and health factors. Only 13.5% (95% confidence interval [CI]: 11.6-15.4%) of participants aware of air quality reported changing their individual behaviors. Males (adjusted odds ratio [AOR]: 0.66, 95% CI: 0.56-0.77) and those without cardiovascular disease (AOR: 0.58, 95% CI: 0.47-0.71) were least likely to take action. Results show that individual action was infrequent among the population. Health promotion of individual intervention is necessary, and this effort may need to target specific subgroups of the population. Further studies on effective individual interventions are needed.

Racial Differences in Age-Related Variations of Testosterone Levels Among US Males: Potential Implications for Prostate Cancer and Personalized Medication.

AIM: The magnitude of the age-related declines in testosterone rather than levels measured at single point in time may be related to the genesis of prostate cancer (PCa). We examined age-related variations of testosterone levels among black and white males, which may provide important insights into racial disparities in PCa incidence and mortality. METHOD: We analyzed data from the 1999-2004 National Health and Nutritional Examination Survey to compare age-related variations in the testosterone levels of 355 black and 631 white males. RESULT: Overall, between the ages of 12 and 15, black males had lower testosterone levels than white males. Testosterone levels increased rapidly with age and reached higher and earlier peak levels in black males compared to white males at 20-30 years of age. After reaching a peak level, testosterone levels declined earlier in blacks than in whites. Further analyses showed that black males had considerably higher levels of testosterone compared to white males aged 20-39 years after adjusting for covariates, including age, body mass index, cigarette smoking, physical activity, and waist circumference; however, no statistically significant differences were observed between the groups at any other age. CONCLUSION: Our study revealed that testosterone levels in black males decrease substantially with increasing age compared to those in white males. This rapid drop in testosterone levels may contribute to racial disparities in PCa. Our findings also suggest that personalized medication for hormone replacement therapy may be necessary to avoid sudden drops in testosterone levels, particularly for black males.

Health effects of air pollution on length of respiratory cancer survival.

BACKGROUND: Air pollution has been extensively and consistently linked with mortality. However, no study has investigated the health effects of air pollution on length of survival among diagnosed respiratory cancer patients. METHODS: In this study, we conducted a population-based study to investigate if air pollution exposure has adverse effects on survival time of respiratory cancer cases in Los Angeles (LA), CA and Honolulu, HI. We selected all White respiratory cancer patients in the two study areas from the 1992-2008 Surveillance Epidemiology and End Results cancer data. Death from respiratory cancer and length of survival were the main outcomes. RESULTS: Kaplan-Meier survival analysis shows that all respiratory cancer cases exposed to high air pollution referring to the individuals from LA had a significantly shorter survival time than the low pollution exposure group referring to those from Honolulu without adjusting for other covariates (p <0.0001). Moreover, the results from the Cox Proportional-Hazards models suggest that exposure to particles less than 10 micrometers in diameter (PM10) was associated with an increased risk of cancer death (HR = 1.48, 95% CI: 1.44-1.52 per 10 µg/m3 increase in PM10) after adjusting for demographic factors and cancer characteristics. Similar results were observed for particles less than 2.5 micrometers in diameter and ozone. CONCLUSION: Our study indicates that air pollution may have deleterious effects on the length of survival among White respiratory cancer patients. This study calls for attention to preventive effort from air pollution for this susceptible population in standard cancer patient care. The findings from this study warrant further investigation.

Association between ozone exposure and onset of stroke in Allegheny County, Pennsylvania, USA, 1994-2000.

BACKGROUND: Epidemiological studies have shown adverse short-term effects of air pollution on health including cardiovascular morbidity and mortality. However, air pollution-related stroke has received less attention. METHODS: In this study, we performed a time-stratified case-crossover analysis to evaluate the relationships between stroke hospital admissions and O3, among patients aged 65 years and older in Allegheny County, Pa., USA, between 1994 and 2000. We also examined whether the effects of air pollutants differed across strata defined by patient demographic characteristics and ambient temperature. RESULTS: Exposures to O3 on the current day increase the risk of total stroke hospitalization by 1.9% (95% CI: 0.01-3.8) per interquartile range increase in concentration. Furthermore, the results suggest that males were more sensitive to adverse health effects of O3 on stroke hospitalization than females. CONCLUSION: These results suggest that O3 has an adverse effect on stroke hospitalization. Specific patient subgroups, such as males, may be at increased risk.