Association between physical activity and inflammatory markers in community-dwelling, middle-aged adults

Physical activity has been known to deter inflammatory process; yet, the evidence is scarce in healthy, middle-aged population. We assessed the association between physical activity and inflammatory biomarkers, including high sensitivity (hs) C-reactive protein, interleukin (IL)-1a,-1b, and-6, tumor necrosis factor (TNF)-a and-b, and monocyte chemotactic protein (MCP)-1 and-3. Functional and leisure-time physical activity was assessed by the International Physical Activity Questionnaire. Inflammatory biomarkers were measured by multiplex enzyme-linked immunosorbent assay. Compared with highly physically active participants based on total metabolic equivalent of task, the most sedentary group had significantly higher odds ratio and [95% confidence interval] for ≥75th percentile of TNF-a (1.64 [1.10–2.44]), TNF-b (1.50 [1.09–2.07]), IL-1b (2.14 [1.49–3.09]), hsIL-1b (1.72 [1.15–2.58]), IL-6 (1.84 [1.24–1.73]), hsIL-6 (2.05 [1.35–3.12]), and MCP-1 (1.91 [1.28–2.87]) levels. Results for IL-1a and MCP-3 were inconsistent, as the least active group had lower odds for above the median IL-1a (0.65 [0.49–0.95]) and MCP-3 (0.71 [0.54–0.93]) yet higher odds for ≥75th percentile IL-1a (2.36 [1.63–3.42]) and MCP-3 (2.44 [1.63–3.64]) levels. Based on duration of moderate-to-vigorous physical activity, sedentary participants had significantly higher odds for above median (1.40 [1.13–1.73]) and ≥75th percentile (1.33 [1.00–1.77]) IL-1b compared with those fulfilling the guideline recommendation. Subgroup analyses showed minimal sex differences. Routine inflammatory assessment may help to achieve primordial prevention of cardiovascular and metabolic diseases. Novelty: Healthy, middle-aged adults with physically active lifestyle were generally at lower odds for elevated inflammatory status. The associations persisted regardless of sex, age, comorbidities, adiposity, and diet.