Plasma homocysteine and lipoprotein profile in patients with peripheral arterial occlusive disease

Several studies have identified moderate hyperhomocysteinemia (HCy) as an i ndependent risk factor for atherosclerosis. The purpose of this case contro l study was to determine lipoprotein profile and homocysteine concentration in serum of 85 male patients with peripheral arterial occlusive disease (P AOD) and in 51 normolipidemic age-matched male controls. Cholesterol, trigl ycerides, and high-density lipoprotein (HDL) cholesterol as well as subfrac tions HDL2 and HDL3 cholesterol, low-density lipoprotein (LDL) cholesterol, apo B, apo A-I, and lipoprotein particles LpA-I and LpA-I:A-II were measur ed in serum. Homocysteine, folic acid, and vitamins Bg and Bit were determi ned with the help of high-pressure liquid chromatography. The 677 C --> T m utation in the methylenetetrahydrofolate reductase (MTHFR) gene was analyze d in PAOD patients. Patients with peripheral arterial occlusive disease sho wed a significantly higher mean concentration of homocysteine than control subjects (p<0.001). There was a negative correlation between the levels of homocysteine and vitamin B-12 as well as folic acid (for vitamin B-12: r=-0 .40 and for folic acid: r=-0.38). The prevalence of hyperhomocysteinemia (H cy >16 mu mol/L) in the patients was 45% in contrast to 8% in controls. HDL cholesterol, HDL3 cholesterol, Apo A-I, and Lp A-I were significantly redu ced in patients and triglycerides were elevated. The elevated plasma homocy steine concentration is frequently seen in homozygous carriers of a point m utation (677 C --> T) in the methylenetetrahydrofolate reductase gene, as t he product of this gene is an enzyme, participating in homocysteine remethy lation. The homozygous state for the 677 C --> T mutation was found in 13.3 % of PAOD patients.