Cancer incidence among male Danish nurses, 1980-2003

The Effect of Shift Work on Urogenital Disease: a Systematic Review

PURPOSE OF REVIEW

Non-standard shift work schedules negatively impact the overall health of shift workers, and several studies have shown that shift work, specifically, is detrimental to urogenital health. The aims of this study are to systematically review the literature and determine the effect of shift work on the outcomes of hypogonadism, male infertility, lower urinary tract symptoms, and urogenital cancers.

RECENT FINDINGS

Recent evidence supports associations between non-standard shift work and an increase in the frequency of prostate cancer and the severity of erectile dysfunction, lower urinary tract symptoms, and hypogonadal symptoms, as well as worsening of semen parameters and fertility. These associations are strengthened by the presence of shift work sleep disorder (SWSD) which affects up to 20% of shift workers. No studies have assessed the impact of shift work on the frequency or severity of nephrolithiasis, interstitial cystitis, pelvic pain, prostatitis, or urinary tract infections. Non-standard shift work has been associated with a variety of negative health outcomes and urologic complications, especially with concurrent shift work sleep disorder. Recognition of these elevated risks among shift workers can aid in more effective screening for urologic conditions.

the risk of cancer among Taiwanese female registered nurses: a nationwide retrospective study

Background

To evaluate the risk of cancer among Taiwanese female registered nurses (RNs) using a nationwide population-based dataset.

Methods

We recruited female RNs without antecedent cancer from the Taiwan National Health Insurance Research database during 2000–2010. Standardized incidence ratios (SIRs) of cancer were calculated. We also compared rates of Papanicolaou (Pap) smear use between the RNs and the general population matched by age and sex.

Results

A total of 2,077 cancers developed among 184,809 female RNs, with a follow-up of 1,371,910 person-years (median follow-up of 7.86 years), leading to an increased SIR of 1.10 [95% confidence interval (CI) 1.05–1.15]. RNs aged between 40–59 years also had a significantly increased SIR (1.14, 95% CI 1.08–1.21). For specific cancer types, RNs had an increased SIR for breast (1.28, 95% CI 1.19–1.37), thyroid (1.26, 95% CI 1.10–1.43), lung and mediastinum (1.36, 95% CI 1.13–1.62), and uterine cancers (1.23, 95% CI 1.01–1.49). A decreased SIR was found for cervix (0.48, 95% CI 0.37–0.61) and liver and biliary tract cancers (0.68, 95% CI 0.50–0.90). Pap smear use averaged 5.80 times per person among female RNs aged 35 years or older and 5.50 times per person in the age-matched control group (p = 0.009).

Conclusion

This study found that overall cancer risk was higher among female RNs than general population. For individual cancers, the risks of breast, lung, thyroid and uterine cancer were higher and the risks of cervix and liver cancer were lower than general population. The lower risk of cervical cancer might be partially explained by the increased use of Pap smears in the RNs group. Further large, unbiased population-based prospective studies are needed to investigate the association between nurses and cancer risk and identify the risk factors of cancer in nurses.