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)-1α, -1β, and -6, tumor necrosis factor (TNF) -α and -β, 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-α (1.64 [1.10-2.44]), TNF-β (1.50 [1.09-2.07]), IL-1β (2.14 [1.49-3.09]), hsIL-1β (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-1α and MCP-3 were inconsistent, as the least active group had lower odds for above the median IL-1α (0.65 [0.49-0.95]) and MCP-3 (0.71 [0.54-0.93]) yet higher odds for ≥75th percentile IL-1α (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-1β 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.