Background: Previous studies have found that hyperhomocysteinemia is an independent risk factor for coronary disease. Homocysteine levels, and factors involved in their increase, are unknown in Spanish patients with coronary disease.
Patients and methods: In 202 Spanish patients with coronary disease (174 men and 28 women) and age < 70 years old, homocysteine, creatinine, fibrinogen, lipoproteins, folic acid and vitamin B12 levels were determined. Controls were 40 healthy subjects whose age was not different from patients.
Results: Plasma homocysteine levels were increased in patients compared to controls (mean [SD] 11.7 [4.2], 95% confidence interval [CI]: 11.1-12.2, vs 8.4 [2.4], 95% CI: 7.7-9.2 mumol/l; p < 0.001). Hyperhomocysteinemia was found in 52 patients and in one control (26% vs 2.5%, odds ratio: 13.5, 95% CI: 1.8-100.8; p = 0.001). Homocysteine levels were positively associated in patients with creatinine level and negatively associated with folic acid level (p = 0.02 for both), but association with age, gender, fibrinogen, lipoproteins and vitamin B12 was not found. By multivariate analysis, folic acid was the only independent variable related with homocysteine levels (odds ratio: 0.32%, 95% CI: 0.122-0.882). In a subgroup of 30 patients with a low profile of cardiovascular risk (total-cholesterol < 225 mg/dl, nonsmokers and without diabetes and hypertension) an increase of homocysteine levels was also found, and 33% of them had hyperhomocysteinemia.
Conclusion: Hyperhomocysteinemia was present in 26% of the patients with coronary disease. A similar percentage was found in the patients with a low profile of cardiovascular risk. Homocysteine levels were negatively associated with folic acid levels.