Active commuting and atherosclerosis in a population-based sample of middle-aged adults: the Swedish CArdioPulmonary...

To investigate the relationship between active commuting and atherosclerosis in middle age using state-of-the-art coronary CT angiography (CCTA).

This cross-sectional study used data from the Swedish CArdioPulmonary bioImage Study (SCAPIS) and included 23 722 randomly recruited individuals aged 50-64 years from six different regions in Sweden. The exposure was commuting mode, assessed using self-reported questionnaires and categorised as year-round walking and/or cycling (active commuting), commuting by bus/train, commuting by car or mixed commuting patterns. The outcome was atherosclerosis, evaluated using CCTA for coronary stenosis and coronary artery calcium (CAC) score and ultrasound for carotid plaques. Associations were analysed using multivariate binomial logistic regression models.

After adjusting for confounders (age, sex, SCAPIS site, education, occupational physical activity and leisure time exercise habits, sleep, diet and smoking habits), active commuting was associated with lower odds of coronary stenosis (OR 0.87; 95% CI 0.80 to 0.94) and a CAC score ≥1 Agatston units (OR 0.93; 95% CI 0.86 to 1.00), as compared with car commuting. No associations were observed between active commuting and the presence of carotid plaques (OR 0.97; 95% CI 0.90 to 1.03). When stratified, the inverse association with coronary stenosis appeared to be somewhat stronger for cycling (OR 0.86; 95% CI 0.78 to 0.95) than for walking (OR 0.89; 95% CI 0.79 to 1.01).

Using advanced CCTA imaging in a large, randomly selected sample of middle-aged adults, we show for the first time that coronary atherosclerosis is less common in active commuters, particularly those cycling, compared with car commuters. While this indicates that active commuting might be a potential preventive measure to reduce atherosclerosis and subsequent cardiovascular disease, further causal analyses are needed to confirm our findings.