Background Job strain is implicated in many cardiovascular diseases, including coronary heart disease and stroke. However, its role in peripheral artery disease (PAD), a major cause of cardiovascular morbidity worldwide, is unclear. We investigated the longitudinal association of job strain with PAD, using individual-level data from 11 prospective, register-linked cohort studies from Finland, Sweden, Denmark and the United Kingdom.

Methods Job strain (a combination of high demands and low control at work) was self-reported at baseline (1985–2008) and PAD diagnoses during the follow-up were ascertained from national hospital registers. Individuals with a pre-baseline hospital record of PAD were excluded from the analyses. Data on job strain, PAD and covariates were harmonised across the studies. We used Cox regression to examine the associations of job strain with PAD in each study in turn, adjusting the association estimates for age, sex, socioeconomic position, tobacco smoking, alcohol intake, body mass index and leisure time physical activity. The study-specific estimates were combined using random effects meta-analyses. Heterogeneity was quantified using τ-squared and I-squared and potential sources for heterogeneity were examined by stratification and meta-regression analyses.

Results Our analyses were based on data from 139,132 men and women, aged 17–70 years. Of these participants, 32,489 (23.4%) reported job strain at baseline. During 1,718,132 person-years at risk (mean follow-up 12.8 years), 667 individuals had a hospital record of PAD (3.88 per 10,000 person-years). Job strain was associated with a 1.41-fold increase (95% confidence interval: 1.11 to 1.80) in the average risk of hospitalisation with PAD, independently of age, sex, socioeconomic position and lifestyle-related characteristics. The study-specific estimates were moderately heterogeneous (τ-squared=0.0427, I-squared: 26.9%), but we found no clear evidence of sex, socioeconomic position, smoking or baseline diabetes explaining the heterogeneity. The average absolute risk difference between the job strain and no strain groups was firmly positive (3.28, 95% confidence interval: 0.78 to 5.78).

Discussion Job strain, a marker of psychosocial stress at work, was associated with small but consistent increase in the risk of hospitalisation with PAD. The risk estimates for PAD were similar in magnitude to those previously estimated for coronary heart disease and ischaemic stroke, suggesting that job strain is at least as important a risk factor for PAD as it is for these severe cardiovascular disease outcomes. Our findings highlight the need for physicians in occupational health and primary care to recognise and target work-related stress as a risk factor for PAD.