Renal function exerts only a minor influence on high plasma homocysteine concentrations in patients with acute...

Area of Science:

• Cardiovascular Medicine
• Nephrology
• Clinical Biochemistry

Background:

• Hyperhomocysteinemia is linked to occlusive vascular disease.
• Reduced renal function secondary to renovascular disease is a proposed cause.
• Serum cystatin C is a sensitive marker for glomerular filtration rate.

Purpose of the Study:

• To investigate the role of subtle renal dysfunction in causing high plasma homocysteine (tHcy) in acute coronary syndrome (ACS) patients.
• To assess the relationship between serum cystatin C, a marker of glomerular filtration, and plasma tHcy levels in ACS patients.

Main Methods:

• Measured serum cystatin C, serum creatinine, plasma homocysteine (tHcy), serum cobalamin, and blood folate in 59 ACS patients with high tHcy, 34 patients with low-normal tHcy, and 50 controls.
• Administered vitamin therapy (folic acid, pyridoxine, cyanocobalamin) to a subgroup of high tHcy patients.
• Analyzed correlations between renal function markers and tHcy levels before and after vitamin therapy.

Main Results:

• Patients with low-normal tHcy showed better renal function markers (lower cystatin C, creatinine) and higher vitamin levels compared to controls and high tHcy patients.
• No significant differences in renal function markers were observed between high tHcy patients and controls.
• Vitamin therapy significantly reduced plasma tHcy but did not strengthen the correlation between cystatin C and tHcy.

Conclusions:

• Subtle renal dysfunction is unlikely to be a primary cause of high plasma tHcy in patients with acute coronary syndromes.
• While vitamin supplementation effectively lowers tHcy, it does not alter the association with renal function, suggesting other etiological factors are more significant.