Documents Knutsson, Anders 4 results

"Objective The aim of this study was to investigate whether shift work (with or without night work) is associated with increased risk of breast cancer.Methods The population consisted of 4036 women. Data were obtained from WOLF (Work, Lipids, and Fibrinogen), a longitudinal cohort study. Information about baseline characteristics was based on questionnaire responses and medical examination. Cancer incidence from baseline to follow-up was obtained from the national cancer registry. Two exposure groups were identified: shift work with and without night work. The group with day work only was used as the reference group in the analysis. Cox regression analysis was used to calculate relative risk.Results In total, 94 women developed breast cancer during follow-up. The average follow-up time was 12.4 years. The hazard ratio for breast cancer was 1.23 [95% confidence interval (95% CI) 0.70–2.17] for shifts without night work and 2.02 (95% CI 1.03–3.95) for shifts with night work. When including only women <60 years of age, the risk estimates were 1.18 (95% CI 0.67–2.07) for shifts without night work, and 2.15 (95% CI 1.10–4.21) for shifts with night work.Conclusions Our results indicate an increased risk for breast cancer among women who work shifts that includes night work.

The aim of this study was to analyze the relationship of job strain (high psychological job demands and low decision latitude) to hypertension, serum lipids, and plasma fibrinogen.No strong associations were found between job strain and plasma fibrinogen. The males reporting job strain had lower levels of total cholesterol and high-density lipoprotein cholesterol than the other males. Similar tendencies were found for the females. The females, but not the males, with job strain had an increased prevalence of hypertension when compared with the subjects with relaxed psychosocial work characteristics. In the subgroups of younger males and females an adverse association between job strain and the ratio between low-density and high-density lipoprotein cholesterol was noted.The results do not support the hypothesis that job strain has an adverse impact on serum total cholesterol and plasma fibrinogen levels. They suggest that an increased risk of coronary heart disease in association with job strain, if causal, is mediated by other factors, possibly partly by hypertension and low levels of high-density lipoprotein cholesterol.

"Objectives: To study cancer morbidity patterns in concrete workers.

Methods: A cohort of 33,503 concrete workers was enrolled in the study from 1971-86. The average duration of follow up was 19.4 years (582,225 person-years). The workers' cancer morbidity was compared with the morbidity of the general population.

Results: A total of 3572 incident cancers were observed. Significantly increased standardised incidence ratios (SIRs) were found for all malignant neoplasms (SIR 107; 95% confidence interval (95%CI) 103 to 110), cancer of the lip (SIR 179; 95%CI 134 to 234), cancer of the stomach (SIR 139; 95%CI 122 to 158), cancer of the lung (SIR 125; 95%CI 114 to 137), and cancer of the prostate (SIR 108; 95%CI 101 to 116). Reduced risk was found for cancer of the large intestine (SIR 80; 95%CI 69 to 93) and cancer of the testis (SIR 50; 95%CI 26 to 87). Smoking was more prevalent among the concrete workers than in the general population (50% v 35%).

Conclusion: The study has shown a slightly increased overall risk of cancer among concrete workers. The increased risk of lung cancer could entirely be due to differences in smoking habits between concrete workers and the general population. There is a possibility that the smoking also has contributed to the increased risks of stomach cancer and lip cancer, but occupational factors may have contributed to these cancer sites."

"Objective:Our aim was to review published literature on the association between shift work and gastrointestinal (GI) disorders.Methods:A systematic review of the literature was conducted of studies that have reported GI symptoms and diseases among shift workers. We used Medline to search for articles from 1966–2009. Next, we manually searched articles in the reference list of each article and previous reviews.Results: Twenty studies met the inclusion criteria. Four of six studies showed a significant association between shift work and GI symptoms, and five of six studies reported an association between shift work and peptic ulcer disease. Two of three studies showed an association between shift work and functional GI disease. Only a few studies have examined gastroesophageal reflux disease, chronic inflammatory bowel diseases, or GI cancers in relation to shift work.Conclusions: Our general judgment is that shift workers appear to have increased risk of GI symptoms and peptic ulcer disease. However, control for potential confounders (eg, smoking, age, socioeconomic status, and other risk factors) was often lacking or insufficient in many of the studies we examined."