Abstract 16492: Is There an Obesity and a Lean Paradox? - The Role of Inflammation and Body Composition in the Obesity Paradox

Abstract

Background_Despite the adverse effects of obesity on almost all aspects of coronary heart disease (CHD), many studies of CHD cohorts have demonstrated an inverse relationship between obesity, as defined by body mass index (BMI), and subsequent prognosis (the “obesity paradox”). The etiology of this paradox and the potential role of inflammation in this process remain unknown.

Patients and Methods_We studied 469 patients with CHD before and after phase II cardiac rehabilitation (CR), dividing them into subjects with significant improvement (IMPROV) in high sensitivity C-reactive protein (HSCRP) (defined as improvement in HSCRP to < 3mg/dl) and without significant improvement (nonIMPROV). Body Fat (BF) was measured using the skinfold method and lean mass index (LMI) was calculated ((1-%BF)*BMI). The population was divided according to age and sex adjusted categories based on LMI and BF, and analyzed by total mortality over 3-year follow-up by National Death Index.

Results_During 3-year follow-up, all-cause mortality was higher in the nonIMPROV group, especially in the low BMI and BF subgroups (table 1); mortality appeared high in both groups with low LMI. In proportional hazard analysis, even after adjusting for ejection fraction and peak O2 consumption, higher BMI was associated with lower mortality in both groups (HR 0.29 in IMPROV (p 0.033) vs 0.51 (p 0.04) in nonIMPROV). Overweightness and obesity by BF, however, was associated with lower mortality in the nonIMPROV group(HR 0.20; p 0.007) but not in the IMPROV group.. Conversely, high LMI was associated with markedly lower mortality in the IMPROV group (HR 0.05; p 0.008) with a trend to lower mortality in the nonIMPROV group (HR 0.12; p 0.12). Conclusions_ Inflammation impacts the relationship between body composition and subsequent mortality, with mortality being particularly high in those with low BMI/BF and persistently elevated CRP, as well as in those with low LMI. Table 1 - 3 Year Mortality after Cardiac Rehab