Aims: Previous studies have found that excessive sport activities are associated with an increased risk of atrial fibrillation (AF). Whether occupational physical activity (OPA) increases the risk for AF is not well studied. We aimed to examine whether OPA influences the risk of AF.
Methods: 80,922 men and women, free from AF, completed in 1997 a questionnaire about their OPA at that time (baseline), and also retrospectively in 1997 their OPA at the age of 30 and 50 years. Participants were categorised into three groups (low, medium and high) based on OPA load. Participants were followed-up in the Swedish National Patient Register for ascertainment of AF. Cox proportional hazards regression models were used to estimate relative risks (RR) with 95% confidence intervals (CI), adjusted for potential confounders.
Results: 11,614 cases of AF were diagnosed during follow-up time of up to 17 years. We observed an increased risk of AF in relation to increased load of OPA regardless of age. Compared with men who reported a low load of OPA, the multivariable RR (95% CI) for men with a high load was 1.10 (1.03-1.17) at 30 years, 1.11 (1.04-1.17) at 50 years and 1.19 (1.10-1.29) at baseline. The results for women were similar with multivariable RR of 1.16 (1.06-1.27) at 30 years, 1.14 (1.05-1.24) at 50 years and 1.11 (0.99-1.24) at baseline.
Conclusion: These findings suggest that high load of OPA previous in life may play a role in increasing the risk for AF in both men and women.
Keywords: Atrial fibrillation; epidemiology; physical activity; risk factors.