Effects of an American Heart Association step I diet and weight loss on lipoprotein lipid levels in obese men with silent myocardial ischemia and reduced high-density lipoprotein cholesterol

Abstract

Reduced plasma concentrations of high-density lipoprotein cholesterol (HDL-C) are a risk factor for coronary artery disease (CAD). In this study, we examined the sequential effects of an isocaloric American Heart Association (AHA) step I diet and a hypocaloric AHA step I diet (AHA step I diet + weight loss) on lipoprotein lipid levels in 14 middle-aged and older (60 +/- 6 years, mean +/- SD) obese (body mass index [BMI] > 27 kg/m2) nondiabetic men with exercise-induced silent myocardial ischemia (SI) and reduced HDL-C levels (0.85 +/- 0.14 mmol/L). Nine men of comparable age and obesity and with no evidence of exercise-induced ischemia that were evaluated longitudinally served as metabolic controls. In men with SI, after 3 months on the isocaloric AHA step I diet plasma triglyceride (TG) levels decreased by 26% (2.25 +/- 0.66 to 1.67 +/- 0.69 mmol/L, P < .005), cholesterol by 12% (5.24 +/- 0.84 to 4.62 +/- 0.78 mmol/L, P < .01), and low-density lipoprotein cholesterol (LDL-C) by 10% (3.40 +/- 0.69 to 3.05 +/- 0.70 mmol/L, P < .01). However, plasma HDL-C levels also decreased by 7% (0.85 +/- 0.14 to 0.79 +/- 0.13 mmol/L, P < .05). Subsequent weight loss (11 +/- 4 kg) in conjunction with the AHA step I diet resulted in an additional decrease of 24% in TG (P < .005), 10% in cholesterol (P < .05), and 10% in LDL-C (P < .05). Plasma HDL-C levels increased by 8% (P < .01), thereby correcting the decline seen on the AHA step I diet alone.(ABSTRACT TRUNCATED AT 250 WORDS)