Plasma Homocysteine in Patients with Coronary and Carotid Artery Disease: A Case Control Study

Introduction: Homocystein (Hcy) is an amino acid and elevated plasma cause endothelial damage, followed with inflammation in the blood vessels and its progression in atherosclerosis. We aimed to evaluate the correlation between cardiovascular disease and serum homocysteine levels..

Methods: We performed a case control analysis of 212 patients, either for cardiovascular risk stratification or for invasive diagnostics and treatment of cardiovascular ischemic disease (CAD). Patients were divided into 4 groups: Group 1. Patients with low risk for CAD, with no symptoms of CAD and total of 10 years risk <10%. Group 2. High-risk patients with no symptoms of CAD, but 10 years total CAD risk of >20%. Group 3. Patients with symptomatic CAD, where angiography was performed and >50% occlusion of at least one coronary vessel was found. Group 4. Patients with carotid artery disease and documented CAD.

Results: Group 1 consists of 56 subjects, of whom 33 (60%) males and 22 (40%) females. Their mean age was 52.18±8.07 years and their average CAD risk was 5.

Group 2 included 60 patients, with average CAD risk of 23.73. There was a statistically significant difference between plasma homocysteine levels between the control and high CAD risk group, as well as between those with CAD and both CAD and CARD (p=0.001). In the high-risk subjects group, the level of homocysteine correlates albeit weak with the total CAD risk (p=0.04). Homocysteine levels correlate with the WBC count (p=0.02). In the subgroup of smokers with high CAD risk, homocysteine correlates with age, total CAD risk, total cholesterol, BUN (define BUN) and creatinine.

Group 3 consisted of 49 subjects with manifested and angiographically proven CAD, out of whom 80% were males and 20% females, mean age 56.06±9.7 years, with average 2 coronary vessels affected. There were significantly higher homocysteine plasma levels between the control group and the group with manifested CAD (p=0.008).There is no significant difference of homocysteine plasma levels between the high risk group and the group with manifested coronary artery disease (15.03□mol/l vs. 16.38□mol/l). In this group, plasma levels of homocysteine correlate only with the highest level of vessel stenosis (>95%) with (p=0.04).

The study population in group 4 showed a mean of IMT 0.9 +..09 mm and mean Hcy plasma levels of 21 + 11 µmol/L. From the evaluated patients with CAD, 82.9% of patients had elevated level of Hcy. From those, one showed elevated Hcy, 79.4 % had hypertension, 58.9 % had hyperlipidemia, 28.2% had diabetes mellitus as additional risk factors for atherosclerosis. 76.9 % of the patients had increased intima-media thickness; in 58.9 % plaques were detected, while 23 % of the patients had significant stenosis: 10.2 % with intermediate–grade stenosis (50-69%) and 12.8 % with high-grade stenosis (70-99 %). 17.1 % of the patients had normal level of Hcy, and in those ones 62.5 % only had increased IMT. We found linear correlation between IMT and HCy levels (r 0.7, p 0.05).

Case control analysis showed significant higher level of Hcy in the group with CAD and carotid artery disease vs. CAD group (p 0.001).

Conclusion:High plasma homocysteine concentrations are associated with high risk for vascular disease and consequently CAD itself and carotid artery disease, as well, proving its likely role in the development of atherosclerosis on inflammatory and metabolic levels.