Abstract 16: Association of Baseline & Longitudinal Changes in Fitness & Body Mass Index With Risk of Heart Failure in Individuals With Type 2 Diabetes Mellitus: An Analysis From the Look Ahead Trial

Abstract

Introduction: Type 2 Diabetes (T2DM) is associated with higher risk for HF. The contributions of baseline measures of and changes in fitness (CRF) toward HF risk in T2DM is not well-established. Methods: Participants of the Look AHEAD trial without prevalent HF randomized to the intensive lifestyle intervention (ILI) vs. usual care arms were included. Incident HF hospitalization and its subtypes [HF with preserved ejection fraction (EF>= 50%, HFpEF) & HF with preserved ejection fraction (EF < 50%, HFrEF)] were adjudicated through the end of 2014 using a validated approach. The associations of baseline CRF estimated from a maximal treadmill test and changes in CRF (from baseline to year 4) with risk of HF and its subtypes were evaluated using adjusted Cox models. Results: Among the 5,109 study participants, there was no significant difference in the risk of HF (n = 257 events) between the ILI vs. usual care groups [HR (95% CI) = 0.96 (0.75 - 1.23)] over 12.4 years follow up. In adjusted analysis, the risk of HF was 39% and 62% lower among moderate fit [Tertile 2] and high fit [Tertile 3] groups, respectively [vs. low fit (Tertile 1), Table]. Among HF subtypes, the risk of HFpEF was 40% lower in moderate fit and 77% lower in the high fit groups (vs. low fit). In contrast, baseline CRF was not associated with risk of HFrEF after adjustment for potential confounders (Table). BMI was also not associated with risk of HF after adjustment for CV risk factors. Among participants with repeat CRF testing (n = 3,902), improvements in CRF and weight loss over 4-year follow-up was significantly associated with lower risk of HF [HR (95% CI) per 10% increase in CRF = 0.90 (0.82 to 0.99), per 10% decrease in BMI = 0.80 (0.69 to 0.94)]. Conclusion: Higher baseline CRF is independently associated with lower risk of HF, particularly HFpEF, among individuals with T2DM. Improvements in CRF and weight loss can significantly lower risk of HF in this high-risk population. However, the ILI implemented in the LookAHEAD trial did not modify the risk of HF among the study participants.