Prostate cancer in firefighting and police work: a systematic review and meta-analysis of epidemiologic studies

OBJECTIVES We conducted a systematic review and meta-analysis to evaluate potential associations between firefighting and police occupations, and prostate cancer incidence and mortality. METHODS Original epidemiological studies published from 1980 to 2017 were identified through PubMed and Web of Science. Studies were included if they contained specific job titles for ever/never firefighting and police work and associated prostate cancer risk estimates with 95% confidence intervals (CI). Study quality was assessed using a 20-point checklist. Prostate cancer meta-risk estimates (mRE) and corresponding 95% CIs were calculated for firefighting and police work separately and by various study characteristics using random effects models. Between-study heterogeneity was evaluated using the I2 score. Publication bias was assessed using Begg's and Egger's tests. RESULTS A total of 26 firefighter and 12 police studies were included in the meta-analysis, with quality assessment scores ranging from 7 to 19 points. For firefighter studies, the prostate cancer incidence mRE was 1.17 (95% CI = 1.08-1.28, I2 = 72%) and the mortality mRE was 1.12 (95% CI = 0.92-1.36, I2 = 50%). The mRE for police incidence studies was 1.14 (95% CI = 1.02-1.28; I2 = 33%); for mortality studies, the mRE was 1.08 (95% CI = 0.80-1.45; I2 = 0%). By study design, mREs for both firefighter and police studies were similar to estimates of incidence and mortality. CONCLUSION Small excess risks of prostate cancer were observed from firefighter studies with moderate to substantial heterogeneity and a relatively small number of police studies, respectively. There is a need for further studies to examine police occupations and to assess unique and shared exposures in firefighting and police work.