ASPO Abstracts
The association of physical activity and sedentary behavior with biomarkers of inflammation among women
Category: Molecular Epidemiology & Environment
Conference Year: 2019
Abstract Body:
Physical activity (PA) and sedentary behavior (SB) have been associated with multiple chronic diseases, including cancer, diabetes, and cardiovascular disease. The impact of PA and SB on inflammatory pathways is one potential mechanism underlying these associations. The aim of this study was to assess the cross-sectional association of PA and SB with inflammatory biomarkers in the prospective Nurses’ Health Studies (NHS & NHSII). We used previously collected data on c-reactive protein (CRP, N=11,104), Interleukin 6 (IL-6, N=8,037), and tumor necrosis factor alpha receptor 2 (TNFαR2, N=7,690) levels in women included as controls in previous nested case-control studies. After applying a batch-correction procedure, biomarker levels were log-transformed. Self-reported data on participation in various physical activities, time spent sitting (TSIT), and covariates were collected using questionnaires near the time of blood collection. Multivariable linear regression models were used to calculate percent differences in biomarker levels between categories of activity or sitting. After adjusting for age, menopausal status, smoking, aspirin use, hormone therapy use, and an inflammatory diet index (Model 1), CRP levels were higher among women with lower total PA. For example, CRP levels were 60.5% (p=<0.0001) higher in women with <3 versus ≥27 MET hours/week of PA. After further adjustment for BMI and TSIT, the percent difference attenuated to 22% but remained significant. Similar trends were seen with PA and IL-6 levels but not TNFαR2 levels. Similarly, in Model 1, CRP levels were higher among women with longer TSIT, particularly sitting while watching TV (55.2% comparing >41 versus ≤10 hours/week, p=<0.0001), however this was attenuated after adjustment for BMI and PA (9.8%, p=0.23). Total TSIT was not associated with IL-6 or TNFαR2, however higher TNFαR2 levels were associated with sitting while watching TV after adjusting for all covariates (6.1% comparing >41 versus ≤10 hours/week, p=0.01). These results suggest that lower PA and sedentariness may play a role in higher inflammation levels. In future analyses, we will evaluate associations with specific types of PA and assess relationships with changes in inflammatory biomarker levels over 10 years.
Keywords: cancerepidemiologyinflammationbiomarkersprevention