Lung cancer mortality in a cohort of UK cotton workers: an extended follow-up

BACKGROUND: A recent systematic review and meta-analysis suggested that occupational exposure to endotoxins protects against lung cancer. To explore this hypothesis further, the follow-up of mortality of a cohort of 3551 workers, who were employed in the British cotton industry during 1966-1971, was extended by 23 years. METHODS: Subjects had originally been recruited to a survey of respiratory disease, which collected information about occupation and smoking habits. Cumulative exposures to endotoxins were estimated from data on endotoxin levels by work areas in cotton mills. Risks of lung cancer were estimated using survival modelling. RESULTS: During follow-up, 2018 deaths were recorded before the age of 90 years, including 128 deaths from lung cancer. After adjustment for smoking, hazard ratios (95% confidence intervals) for cumulative endotoxin exposures of =30,000, >30,000 and =200,000, >200,000 and =400,000, >400,000 and =600,000 and >600,000 endotoxin units (EU) m(-3) years were 1, 0.8 (0.5-1.6), 0.7 (0.4-1.3), 0.6 (0.3-1.0) and 0.5 (0.3-0.9), respectively (P for trend=0.005). CONCLUSION: Our findings strengthen the evidence that occupational exposure to endotoxins protects against lung cancer, and suggest that the effect depends on cumulative dose and persists after exposure ceases

Lung cancer mortality in a cohort of UK cotton workers: an extended follow-up

BACKGROUND: A recent systematic review and meta-analysis suggested that occupational exposure to endotoxins protects against lung cancer. To explore this hypothesis further, the follow-up of mortality of a cohort of 3551 workers, who were employed in the British cotton industry during 1966-1971, was extended by 23 years. METHODS: Subjects had originally been recruited to a survey of respiratory disease, which collected information about occupation and smoking habits. Cumulative exposures to endotoxins were estimated from data on endotoxin levels by work areas in cotton mills. Risks of lung cancer were estimated using survival modelling. RESULTS: During follow-up, 2018 deaths were recorded before the age of 90 years, including 128 deaths from lung cancer. After adjustment for smoking, hazard ratios (95% confidence intervals) for cumulative endotoxin exposures of =30,000, >30,000 and =200,000, >200,000 and =400,000, >400,000 and =600,000 and >600,000 endotoxin units (EU) m(-3) years were 1, 0.8 (0.5-1.6), 0.7 (0.4-1.3), 0.6 (0.3-1.0) and 0.5 (0.3-0.9), respectively (P for trend=0.005). CONCLUSION: Our findings strengthen the evidence that occupational exposure to endotoxins protects against lung cancer, and suggest that the effect depends on cumulative dose and persists after exposure ceases

Lung cancer mortality in the European cohort of titanium dioxide workers: a reanalysis of the exposure-response relationship.

Animal bioassays have demonstrated convincing evidence of the potential carcinogenicity to humans of titanium dioxide (TiO <sub>2</sub> ), but limitations in cohort studies have been identified, among which is the healthy worker survivor effect (HWSE). We aimed to address this bias in a pooled study of four cohorts of TiO <sub>2</sub> workers. We reanalysed data on respirable TiO <sub>2</sub> dust exposure and lung cancer mortality among 7341 male workers employed in TiO <sub>2</sub> production in Finland, France, UK and Italy using the parametric g-formula, considering three hypothetical interventions: setting annual exposures at 2.4 (U.S. occupational exposure limit), 0.3 (German limit) and 0 mg/m <sup>3</sup> for 25 and 35 years. The HWSE was evidenced. Taking this into account, we observed a positive association between lagged cumulative exposure to TiO <sub>2</sub> and lung cancer mortality. The estimated number of lung cancer deaths at each age group decreased across increasingly stringent intervention levels. At age 70 years, the estimated number of lung cancer deaths expected in the cohort after 35-year exposure was 293 for exposure set at 2.4 mg/m <sup>3</sup> , 235 for exposure set at 0.3 mg/m <sup>3</sup> , and 211 for exposure set at 0 mg/m <sup>3</sup> . This analysis shows that HWSE can hide an exposure-response relationship. It also shows that TiO <sub>2</sub> epidemiological data could demonstrate an exposure-effects relationship if analysed appropriately. More epidemiological studies and similar reanalyses of existing cohort studies are warranted to corroborate the human carcinogenicity of TiO <sub>2</sub> . This human evidence, when combined with the animal evidence, strengthens the overall evidence of carcinogenicity of TiO <sub>2</sub>

Predictors of Occupational Burnout: A Systematic Review.

We aimed to review occupational burnout predictors, considering their type, effect size and role (protective versus harmful), and the overall evidence of their importance. MEDLINE, PsycINFO, and Embase were searched from January 1990 to August 2018 for longitudinal studies examining any predictor of occupational burnout among workers. We arranged predictors in four families and 13 subfamilies of homogenous constructs. The plots of z-scores per predictor type enabled graphical discrimination of the effects. The vote-counting and binomial test enabled discrimination of the effect direction. The size of the effect was estimated using Cohen's formula. The risk of bias and the overall evidence were assessed using the MEVORECH and GRADE methods, respectively. Eighty-five studies examining 261 predictors were included. We found a moderate quality of evidence for the harmful effects of the job demands subfamily (six predictors), and negative job attitudes, with effect sizes from small to medium. We also found a moderate quality of evidence for the protective effect of adaptive coping (small effect sizes) and leisure (small to medium effect sizes). Preventive interventions for occupational burnout might benefit from intervening on the established predictors regarding reducing job demands and negative job attitudes and promoting adaptive coping and leisure