Homocysteine, vitamins and gene mutations in peripheral arterial disease

A case–control study was undertaken involving 51 consecutive patients with peripheral artery obstructive disease (PAOD) scheduled for angioplasty. Blood samples of these patients were analysed for plasma homocysteine (tHcy) and levels of vitamin B12 and folate, and the MTHFR gene was assessed for mutation. Patients were compared with age- and sex-matched controls who did not present with cardiovascular risk factors. Mean tHcy did not differ between cases and controls (13.3 ± 5.7 and 12.6 ± 4.9 μmol/l, P = 0.49). More patients were above the 95th percentile as determined from the data in the control group with an odds ratio (OR) that almost reached statistical significance [OR, 2.8; 95% confidence interval (CI), 0.9–8.7], but on separate analyses only female patients showed higher tHcy than female controls (15.6 versus 12.0 μmol/l, P = 0.05), with an odds ratio for tHcy above the 95th percentile of 10.5 (95% CI, 1.1–96.6). The TT genotype of the MTHFR gene was found in 24% of the patients and in 12% of the controls (OR, 2.3; 95% CI, 0.8–6.7). Our findings point to a modest association between tHcy and PAOD, with a difference between cases and controls restricted to the highest percentile in female patients. A weak but not significant association was also found for the TT genotype of the MTHFR gene.