Current prevalence of vitamin B 6 deficiency in hemodialysis and peritoneal dialysis patients

Abstract

Objective: To describe the current prevalence of vitamin B 6 deficiency based on erythrocyte glutamic pyruvic transaminase (EGPT) index in dialysis patients. Design: Cross-sectional descriptive study. Setting: Four ambulatory clinical sites, including two hemodialysis clinics, one outpatient clinic for peritoneal dialysis patients, and one site providing care to both hemodialysis and peritoneal dialysis patients (a university-affiliated medical center). Patients: One hundred five adult dialysis patients (63 men and 42 women; ages 21 to 84 years) participated in this study. The ethnic makeup of the patient population in this study is as follows: 76 white, 24 black, and 5 patients of unknown ethnicity. Seventy-five percent were hemodialysis patients, and 25% were peritoneal dialysis patients. Intervention: Vitamin B6 status was measured with the EGPT index. Assessment of dietary intake during the preceding 3 months was conducted with a standardized food frequency questionnaire. Body composition was estimated with skinfold thickness measures. Main outcome measure: Fifteen (14%) patients were found to be vitamin B 6 deficient on the basis of an abnormal EGPT index of ≥1.25. Vitamin B6 supplementation, dietary vitamin B 6 or protein intake, type of dialysis, medication usage, gender, age, and ethnic group were not associated with or predictive of vitamin B6 status. Diabetes comorbidity and abnormal EGPT index were significantly associated ( P < .02), and logistic regression analysis revealed diabetes to be a significant independent predictor of vitamin B 6 deficiency (odds ratio = 7.32, 95% confidence interval = 2.06–25.99). Conclusion: Diabetes comorbidity is associated with increased risk for vitamin B 6 deficiency in dialysis patients.