Occupational physical activity and stroke mortality in male Swedish construction workers between 1971 and 2015

Abstract

Background: Contrary to leisure-time physical activity, high levels of occupational physical activity (OPA) have been linked to cardiovascular disease and mortality. Many occupations in the construction industry are known to have high levels of OPA. Aims: This study investigated OPA and stroke mortality risk among 299 382 Swedish male construction workers. Methods: OPA was derived from job titles and categorized as low, medium or high, and stroke mortality was ascertained via the Swedish National Cause of Death Register. The average follow-up was 24 years resulting in a total of 6.9 million person-years, during which 4606 participants died from stroke. Relative risks were estimated with robust Poisson regressions and adjusted for age, calendar year, body mass index and smoking. Results: The relative risk for overall stroke mortality was higher in the medium and high OPA groups compared to the low OPA group [1.15 (1.04, 1.27) and 1.13 (1.04, 1.23), respectively], with no clear dose–response association. Age-stratified analyses showed that higher OPA increased stroke mortality risk in participants between 70 and 89 years. Participants with high versus low OPA had a higher risk of ischaemic stroke mortality [1.15 (1.01, 1.31)]. Conclusions: Construction workers with high OPA have a slight increase in overall stroke mortality, mainly after retirement.