Abstract 18253: Hematocrit Level is Associated With Subclinical Vascular Inflammation in a Middle-Aged Brazilian Population

Abstract

BACKGROUND: Hematocrit (Hct) has been inconsistently reported to be a risk marker of cardiovascular morbidity and mortality. Previous studies have shown some association between Hct and cardiovascular risk, however, its association with subclinical disease is not clear. We aimed to investigate whether Hct is related to subclinical vascular inflammation in a middle-aged population. METHODS: We evaluated 6,437 healthy Brazilian subjects (43±10 years, 79% males) without clinical coronary heart disease between November 2008 and July 2010. A C-reactive protein (CRP) ≥ 3mg/dl was used as a marker for vascular inflammation and Hct was divided into quartiles. Anemia was defined as a hematocrit <36% in women and <39% in men. RESULTS: Mean±SD Hct was 43±4%. Overall, one third (31%) had elevated hs-CRP and 5% were anemic. The prevalence of elevated hs-CRP was significantly lower across Hct quartiles (1 st =35%, 2 nd =31%, 3 rd =29%, 4 th =29%, p=0.001). In addition, those with anemia were more likely to have a higher CRP level compared to those with normal Hct (36% vs. 31%, p=0.06). As shown in table below, even after controlling for confounding variables higher Hct levels were 29-35% less likely to have elevated hs-CRP levels. In fully adjusted model, presence of anemia was associated with 1.31 fold (95% CI 1.02-1.68) likelihood of elevated CRP. CONCLUSIONS: In our study, individuals with anemia and lower Hct were more likely to have higher burden of subclinical inflammation; however, causality cannot be proved due to cross-sectional nature of the study. Further prospective studies are needed to fully understand the interactions of maintaining an optimal Hct.