Whelton SP, et al. - Researchers determined the impact of fitness on the association between isolated low high-density lipoprotein cholesterol (HDL-C) and mortality in patients in the Henry Ford Exercise Testing Project (FIT Project). Participants were asked to complete a physician referred treadmill stress test. Excluded subjects were those prescribed lipid-lowering medications or with known cardiovascular disease. The definition of isolated low HDL-C was HDL-C <40mg/dL for men and <50mg/dL for women with low-density lipoprotein cholesterol (LDL-C) and triglycerides <100mg/dL (n=688). Via Social Security Death Index linkage, mortality was determined. Patients with isolated low HDL-C had a mean age of 48.9±12.9 years and 62.9% were women. A mean follow-up of 10.3±5 years was performed, during which death of 12.8% of patients with isolated low HDL-C and 8.7% with optimal lipids was reported. They found that patients with isolated low HDL-C fitness significantly improved risk stratification. An increased totality mortality risk was observed for only those with lower fitness.