Plasma homocysteine levels in patients with coronary heart disease.

Hyperhomocysteinemia is being identified as a risk factor for coronary heart disease but its role among Asian Indians has not been studied. This has practical importance because (1) the data generated in the West may not represent Indian population, and (2) the condition is remediable. To assess the magnitude of this problem, we studied 56 patients with coronary heart disease, and 53 control subjects. Details of diet, smoking, medication, hypertension and diabetes were recorded; lipids and sugar levels were estimated in all. Patients with renal and liver diseases were excluded. Serum homocysteine was estimated using liquid chromatography. Both the groups were comparable by age and sex. Higher, but statistically insignificant homocysteine levels were seen in patients with coronary heart disease: 10.98 +/- 9.04 nmol/ml vs 9.41 +/- 3.60 nmol/ml in control subjects. Among males, higher, but statistically insignificant levels were seen in coronary heart disease patients: 11.96 +/- 9.41 nmol/ml vs 9.87 +/- 3.50 nmol/ ml in control subjects; among females, the levels were lower though not significant: 5.10 +/- 1.64 nmol/ml vs 6.39 +/- 2.99 nmol/ml. Sub-group analysis with age 40 as dividing point did not show significant difference. Six (10.7%) patients with coronary heart disease and three (5.7%) control subjects had homocysteine levels above 95th percentile of control subjects (p = NS). Twenty-three (41.1%) coronary heart disease patients and 19 (35.9%) control subjects had levels above 10 nmol/ml (p = NS). We conclude that homocysteine is not a major risk factor for coronary heart disease in the study population. The lack of statistical significance could be due to inadequate sample size although some past studies reporting statistically significant association between coronary heart disease and homocysteine involved similar or smaller number of subjects. Larger studies are warranted to see if ethnic differences also have any role.