Abstract 20292: The Interaction Between Isolated Low High-Density Lipoprotein Cholesterol With Fitness and Mortality: The Henry Ford Exercise Testing Project (FIT Project)
Introduction: Isolated low high-density lipoprotein cholesterol (HDL-C) is associated with lower fitness and an increased risk of cardiovascular disease (CVD). Whether the association between isolated low HDL-C and mortality is impacted by fitness is uncertain.
Methods: We examined the association of isolated low HDL-C with fitness and mortality in 44,896 participants free of CVD at baseline and not on lipid lowering therapy in The FIT Project. Fitness was directly measured during a physician referred treadmill stress test and categorized as <6, ≥6-10, and ≥10 METS. Isolated low HDL-C was defined as a HDL-C <40 mg/dL for men and <50 mg/dL for women with LDL-C and triglyceride levels <100 mg/dL, while an optimal lipid panel was defined as a HDL-C ≥40 mg/dL for men and ≥50 mg/dL for women with LDL-C and triglyceride levels <100 mg/dL. The risk of mortality was calculated using Cox Proportional hazard models.
Results: Over a mean follow-up of 11.0 (±4) years there were 88 deaths among the 688 participants with an isolated low HDL-C. Among those with an isolated low HDL-C 14% achieved <6 METS while 60% achieved ≥10 METS. The mortality rate per 1,000 person years for participants with isolated low HDL-C was 53.0 and 3.1 for those who achieved <6 and ≥10 METS respectively, while it was 34.3 and 3.3 respectively for those with optimal lipids. Kaplan-Meier models showed a very low long-term hazard of mortality for persons with isolated low HDL-C who achieved ≥10 METS (Figure). In fully adjusted Cox models the hazard of mortality for those with isolated low HDL-C compared to those with optimal lipids was 1.76 (95% CI 1.30-2.38), 1.93 (95% CI 1.31-2.86), and 1.05 (0.61-1.82) across increasing METS categories.
Conclusions: Individuals with a low fitness level and isolated low HDL-C are at increased risk for mortality compared to those with optimal lipids. Cardiovascular fitness can significantly improve risk stratification for individuals with isolated low HDL-C, with few events when ≥10 METS.
Author Disclosures: S. Whelton: None. Z. Dardari: None. C. Brawner: None. J. Ehrman: None. S. Keteyian: None. M. Al Mallah: None. M. Blaha: None.
- © 2016 by American Heart Association, Inc.