Lipoprotein(a) in coronary heart disease: a case-control study.

To determine the significance of lipoprotein(a) levels in coronary heart disease patients, a case-control study was performed with 48 newly diagnosed coronary heart disease patients and 23 controls who were evaluated using clinical history and biochemical examination. Lipoprotein(a) was measured by quantitative latex-enhanced immunoturbidimetric method. Geometric means of biochemical parameters were obtained. Comprehensive lipid tetrad index was calculated using a previously validated formula. There was no significant difference in prevalence of diabetes, hypertension and smoking in cases and controls. Dietary intake of calories, fats, fatty acids and antioxidant vitamins was also similar. The levels of fasting glucose, cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides were not significantly different in cases and controls (p > 0.05). Low-density lipoprotein/high-density lipoprotein ratio (4.33 +/- 1.5 vs 4.29 +/- 1.8) and total cholesterol/high-density lipoprotein ratio (6.59 + 1.7 vs 6.69 +/- 2.2) were similar. The mean lipoprotein(a) levels were significantly greater in cases (11.95 +/- 2.8 mg/dL, range 1-102 mg/dL) as compared to controls (6.68 +/- 3.4 mg/dL, range 1-73 mg/dL) (t = 2.08, p = 0.041). As compared to controls, in coronary heart disease cases, mean lipoprotein(a) levels in patients upto 50 years (10.27 +/- 2.8 vs 7.27 +/- 3.4 mg/dL) as well as those over 50 years (12.99 +/- 2.9 vs 4.91 +/- 3.5 mg/dL) were significantly more (p < 0.05). Coronary heart disease patients had a slightly greater prevalence of high lipoprotein(a) levels, 20 mg/dL or more (31.3 vs 13.0%; chi 2 = 2.83, l-tailed p < 0.05). Comprehensive lipid tetrad index (total cholesterol x triglycerides x lipoprotein(a) divided by high-density lipoprotein cholesterol) was also slightly higher in cases (14688.2 +/- 3.6) than in controls (8358.2 +/- 4.3) (t = 1.68, 1-tailed p < 0.05). This study shows that lipoprotein(a) levels are significantly more in both younger and older coronary heart disease patients as compared to controls.

Dietary and serum iron, body iron stores and coronary heart disease.

OBJECTIVES: To determine the role of body-iron stores as measured by serum iron, total iron binding capacity (TIBC), transferrin, ferritin and ferritin:transferrin ratio (FTR) in patients with coronary heart disease (CHD). METHODS: A case-control study was performed in 58 newly diagnosed CHD patients and 24 controls who were evaluated using clinical history, dietary history and biochemical examination. Dietary iron was determined by history; serum iron and TIBC were measured biochemically and ferritin by enzyme-linked immunoassay. Case-control comparisons were performed by non-parametric Mann-Whitney test. RESULTS: There was no significant difference in mean age, prevalence of diabetes, hypertension and smoking, and dietary intake of calories and fats in cases and controls. Dietary iron intake was 11.2 +/- 3.4 mg/day in cases and 11.3 +/- 3.8 mg/day in controls (p > 0.05). Serum fasting glucose, cholesterol, LDL cholesterol, HDL cholesterol and triglycerides were not significantly different in cases and controls (p > 0.05). LDL/HDL ratio (4.17 +/- 1.4 vs. 4.62 +/- 2.3) and total cholesterol/HDL ratio (6.47 +/- 1.6 vs. 6.91 +/- 2.4) were also similar. In the whole study group serum iron (54.8 +/- 35.7 mcg/dl), transferrin (11.6 +/- 7.4%) and ferritin (52.4 +/- 57.8 ng/ml) levels were low. In cases as compared to controls serum iron (56.9 +/- 31 vs. 49.6 +/- 45 mcg/dl; z = 1.707, p = 0.088) and transferrin saturation (12.5 +/- 7.8 vs. 9.5 +/- 6.2%; z = 1.83, p = 0.066) were slightly more. Ferritin levels (48.8 +/- 55 vs. 60.9 +/- 64 ng/ml; z = 2.048, p = 0.040) as well as FTR (5.51 +/- 8.6 vs 7.47 +/- 6.1, z = 2.054, p = 0.040) was significantly lower in cases. CONCLUSIONS: In Indian CHD patients the body iron stores are lower as compared to controls.