Independent and synergistic associations of asthma and obesity with systemic inflammation in adolescents.

INTRODUCTION: Both asthma and obesity often occur in the same individual. Each increases the risk of cardiovascular disease (CVD) with systemic inflammation likely playing a vital role. We examined the independent and synergistic associations of asthma and obesity with systemic inflammation using high-sensitivity C-reactive protein (hs-CRP) levels in adolescents. METHODS: This study involves the cross-sectional design carried out in the adolescent and respiratory medicine practices in a children's hospital. Out of 124 adolescents (mean age 16.1 ± 2.3 years), who were either of obese (N = 75) or of normal weight (N = 49). 51 had asthma (18 normal weight and 33 obese). RESULTS: hs-CRP levels were higher in obese versus normal weight groups (geometric mean ± SD: 2.38 ± 2.91 vs. 0.72 ± 3.54; p < .001), and in the asthmatic versus non-asthmatic groups (geometric mean ± SD: 1.21 ± 3.71 vs.1.96 ± 3.28; p = .039). We found a trend of increasing hs-CRP levels across the four groups (p < .001), with the obese asthmatic group having the highest level. In multivariate regression, we found a strong association between obesity and log-CRP (ß ± SE: 1.43 ± 0.23; p < .001) and a moderate association between asthma and log-CRP (ß ± SE: 0.48 ± 0.21; p < .028), with additive synergy between obesity and asthma. CONCLUSIONS: Both asthma and obesity are independently and synergistically associated with systemic inflammation. These findings underline the need of a multifaceted approach to address CVD risk in adolescence.