Dysglycemia and incident heart failure among blacks: The jackson heart study

Background We aimed to investigate the associations of glycemic markers (hemoglobin A(1C) [HbA(1C)], fasting plasma glucose [FPG] and glycemic status [normoglycemia, prediabetes and diabetes]) with incident heart failure (HF) and its subtypes, among Blacks. Methods We included 2,290 community-dwelling Blacks (64% women, mean age 58 years) without prevalent HF from the Jackson Heart Study who attended the second exam (2005 - 2008). The associations between glycemic markers and incident HF (and subtypes including HF with preserved ejection fraction [HFpEF] and reduced ejection fraction [HFrEF]) were evaluated using Cox proportional hazards regression models, adjusting for risk factors and coronary heart disease. Results There were 119 incident HF events (48 HFpEF, 58 HFrEF, and 13 unclassified HF events) over a median follow-up of 10.5 years. Higher levels of HbA1C (HR per SD increment, 1.30; 95% CI 1.12, 1.51) and FPG (HR per SD increment FPG: 1.32; 95% CI: 1.17, 1.48) were associated with a higher risk of incident HF. Compared to normal glycemia, diabetes status was associated with a higher risk of incident HF (HR: 1.24; 95%CI: 1.02, 2.05). HbA1C was significantly associated with higher risks of HFpEF (HR per SD increment: 1.41, 95% CI: 1.18, 1.69) and HFrEF (HR per SD increment: 1.32; 95% CI: 1.12, 1.56). FPG was significantly associated with higher risk of HFpEF (HR per SD increment: 1.35, 95% CI: 1.14, 1.62) but not HFrEF (HR per SD increment: 1.12; 95% CI: 0.53, 2.35). Conclusions Among community-dwelling Blacks, higher levels of glycemic markers were associated with higher risk of HF subtypes.