Workplace social capital and risk of chronic and severe hypertension: A cohort study

Objective: The association between workplace factors and the development of hypertension remains uncertain. We examined the risk of hypertension as a function of workplace social capital, that is, social cohesion, trust and reciprocity in the workplace. Methods: A total of 11 777 male and 49 145 female employees free of chronic hypertension at baseline in 2000-2004 were followed up for incident hypertension until the end of 2005 (the Finnish Public Sector Study). We used survey responses from the participants and their coworkers in the same work unit to assess workplace social capital at baseline. Follow-up for incident hypertension was based on record linkage to national health registers (mean follow-up 3.5 years, 1424 incident hypertension cases). Results: Male employees in work units characterized by low workplace social capital were 40-60% more likely to develop chronic hypertension compared to men in work units with high social capital [age-adjusted hazard ratio 1.57, 95% confidence interval (CI) 1.15-2.14 for self-assessed social capital and 1.41, 95% CI 1.01-1.97 for coworkers' assessment]. According to path analysis adjusted for covariates, the association between low self-reported social capital and hypertension was partially mediated by obesity (P for pathway = 0.02) and alcohol consumption (P = 0.03). For coworker-assessed social capital, the corresponding mediation pathways did not reach statistical significance (P = 0.055 and 0.22, respectively). No association between workplace social capital and hypertension was found for women. Conclusion: These data suggest that low self-reported workplace social capital is associated with increased near-term risk of hypertension in men in part due to unhealthy lifestyle.