Relationship between Serum Vitamin D Levels and Health-Related Quality of Life in Maintenance Hemodialysis Patients

Abstract

Objectives: Aim of the study was investigating the effect of serum vitamin D levels on health-related quality of life in hemodialysis patients. Method: One-hundred and twenty-three maintenance hemodialysis patients were enrolled in this cross-sectional study. Patients divided into 2 groups according to serum vitamin D levels. A serum 25-hydroxyvitamin D (25[OH] D) level of < 20 ng/mL was identified as vitamin D deficiency (n = 78), and a serum level of ≥20 ng/mL was identified as normal (n = 45). Kidney Disease Quality of Life 36 (KDQOL-36) survey was used for quality of life measurement. Scores of the all of 5 subscales of KDQOL-36 were calculated. Multiple linear regression analyses were used to define independent risk factors affecting the survey. Results: Mean age of patients was 62 and 56% of patients were male. Mean 25(OH) D levels were 11.86 and 29.57 ng/mL, respectively, in 2 groups. There was statistically significant difference between age and Kt/V levels between 2 groups (p = 0.008 and p = 0.041). Age and gender were found as significant predictors of vitamin D deficiency (p = 0.026 and p = 0.021). In symptom and problem list subscale, gender and comorbidity were detected as independent risk factors (p = 0.050 and p = 0.032). Comorbidity was the only independent risk factor for effect of kidney disease subscale (p < 0.001). Independent risk factors associated with burden of kidney disease subscale were comorbidity and serum 25 (OH) D levels (p = 0.003 and p = 0.023). Serum 25(OH) D, gender, and comorbidity were independently associated with physical component summary (PCS) subscale (p < 0.001, p = 0.008, and p = 0.011). The only independently associated factor with mental component summary (MCS) was serum 25(OH) D (p < 0.001). Conclusion: We first showed the relationship between serum vitamin D levels and KDQOL-36 in hemodialysis patients. Lower serum vitamin D levels were negatively associated with burden of kidney disease, PCS, and MCS subscales.