Hyperhomocysteinemia and restenosis

This study was undertaken to assess the effect of plasma homocysteine level on angiographic restenosis 6 months after coronary angioplasty. The plasma homocysteine level was measured in 100 consecutive patients at the time of coronary angioplasty, 56 patients who attended a 6-month follow-up angiogram being enrolled to the study; the 44 patients without a control coronary angiogram were not enrolled. Patients with and without angiographic restenosis were designated as groups A (n = 34) and B (n = 22) respectively. The baseline demographic (groups A and B), angiographic (groups A and B) and procedural characteristics were similar in both groups. The mean plasma homocysteine level (SD) was 15.2 (7.7) and 11.1 (2.5) mumol/l in groups A and B respectively (P = 0.007; 95% CI -6.9 to -1.1). With respect to the plasma homocysteine level, the upper and the lower thirds were compared by binary logistic regression (the lower third homocysteine level being < 10.6 mumol/l and the upper third homocysteine level > 14.1 mumol/l). The angiographic restenosis rate for the lower and upper tertiles was 47.4% and 89.5% respectively (P = 0.01; OR = 9.4; 95% CI 1.6-52.7). After adjustment for age and sex, the statistical significance did not change (P = 0.013; OR = 9.43; 95% CI 1.6-54.9). Even after adjustment for age, sex, smoking, hypertension, hypercholesterolemia, and diabetes mellitus, there was a statistically significant difference between the upper and lower tertiles (P = 0.008; OR = 41.3; 95% CI 2.6-635). Increased plasma homocysteine level and diabetes mellitus were independent risk factors for angiographic restenosis after percutaneous transluminal coronary angioplasty and coronary stenting.