Association between different domains of physical activity and markers of inflammation

Physical activity has recently been established as a potential modifier of the inflammatory process, suggesting that it mitigates inflammation and consequently reduces the incidence of several chronic diseases such as cardiovascular events.

This study examined the association between different domains ofself-reported physical activity (work, transportation, household, and leisure time) and three inflammatory markers (fibrinogen, C-reactive protein (CRP), and interleukin 6 (IL-6)). Study subjects included 796 men and women aged 35-74 yr with complete data for the main study variables who participated in the 1989/1990 MONItoring trends and determinants in CArdiovascular disease (MONICA) Augsburg Survey. Data were collected using the MONICA Optional Study on Physical Activity (MOSPA) questionnaire, and activity levels were classified into low, moderate, and vigorous physical activities.

Fibrinogen showed an inverse relationship with higher levels of work (Ptrend = 0.038), transportation (Ptrend = 0.025), leisure time (Ptrend = 0.013), and summary physical activity (Ptrend< 0.001). This relationship was still observed after adjusting for age and sex and further correction for body mass index, waist-to-hip ratio, smoking status, hypertension, diabetes, total-to-HDL cholesterol ratio, education, and self-reported limited physical activity due to health problems. IL-6 showed significant results for transportation (Ptrend = 0.031), leisure time (Ptrend = 0.016), and summary physical activity (Ptrend < 0.001), whereas CRP was inversely related with the summary activity (Ptrend = 0.003) in the fully adjusted model. No statistically significant inverse association between household physical activity and any of the investigated markers was found. We observed interactions between summary physical activity and smoking (fibrinogen: P = 0.003) as well as ex-smoking (CRP: P < 0.001; IL-6: P = 0.049).

These data indicate that beyond leisure time, work and transportation physical activity may reduce inflammation.