Dietary supplement use among patients with chronic kidney disease

Abstract

Background: Dietary supplements (DS) are available over the counter, but patients with impaired renal function are specifically at risk for toxicity when consuming certain DS. The aim of this study was to evaluate the prevalence and characteristics of DS use in patients with chronic kidney disease (CKD).

Material and methods: A cross-sectional, controlled DS use survey (22 questions) was conducted among 180 CKD patients (stage 1-5, dialysis, kidney transplant), with 60 patients without CKD serving as controls.

Results: DS use did not differ significantly between subjects with and without CKD, unless the CKD patients were on dialysis. In the CKD group, 20% admitted to use DS regularly and 22% did not take the mat all. In the controls, DS consumption was 17% and 13%, respectively (NS). The DS use was higher among women ascompared to men (89% vs. 70%; p < 0.005), and people living in cities versus those living in the country side (81% vs. 63%; p < 0.05). DS most commonly used were: vitamins, minerals, and herbs. Major indications for DS use included: musculoskeletal issues, general health improvement and prevention of urinary tract infections. Subgroup analyses revealed that dialysis patients were characterized by a significantly higher DS use in comparison to CKD stage 1-5 subjects and renal transplant recipients. The decision to introduce DS was made by the physician in 54% of cases; by a pharmacist in 9% of cases, and by the patients themselves in 37%. Only 21% of patients with CKD, and 27% of subjects without CKD, declared knowledge of any possible side-effects associated with DS (NS).

Conclusions: The use of DS among patients with CKD is similar to patients without CKD, with the exception of those on dialysis. Vitamins and minerals were the most commonly reported DS consumed. The knowledge on potential side-effectof DS was limited to approximately one-fourth of those surveyed.

Keywords: chronic kidney disease; dialysis; dietary supplements; minerals; toxicity; vitamins.