The influence of estimated creatinine clearance on plasma homocysteine in hypertensive patients with normal serum creatinine

Objectives: To examine the relation of estimated creatinine clearance (eCrCl) and plasma total homocysteine (tHcy) in hypertensive patients with a normal serum creatinine level. Design and methods: A total of 137 hypertensive patients (mean age 66.6?years, 69?men) with serum creatinine level ? 1.5?mg/dL gave 10-h fasting blood samples for measurement of tHcy, serum folic acid, and serum vitamin B12. Results: 95 patients fell into a chronic renal insufficiency (CRI) group (eCrCl ? 60?mL/min/1.73?m2) and 42 into a normal renal function (NRF) group (eCrCl > 60?mL/min/1.73?m2). The CRI group was older (p < 0.001), had higher tHcy (p < 0.001), higher serum urea nitrogen (p < 0.001), higher serum creatinine (p < 0.001), lower eCrCl (p < 0.001), and lower diastolic blood pressure (p = 0.001). In univariate analysis, eCrCl had the strongest correlation with tHcy (r = - 0.453, p < 0.001). Significant correlations, ranging in decreasing order from r = - 0.418, p < 0.001 to r = - 0.170, p = 0.047, were also noted between tHcy and twelve other variables. In multivariate analysis, only eCrCl (p < 0.001), usage of fibrate (p < 0.001), serum level of vitamin B12 (p = 0.002), serum level of folic acid (p = 0.009), and smoking (p = 0.027) were independent predictors of tHcy. Conclusion: eCrCl is a strong independent predictor of tHcy in hypertensive patients with normal serum creatinine. ? 2006 The Canadian Society of Clinical Chemists.