Does Hypovitaminosis D Have a Correlation with Peripheral Polyneuropathy Among Uremic Patients?

Abstract

Background: Chronic kidney disease (CKD), is a syndrome that distresses 11% of the general population. A progressive decline in the renal ability to synthesize an active form of vitamin D (vitD), and failure to preserve physiological vitD levels, required for normal body systems is one of the uremic sequels. Peripheral neuropathy (PNP) is a common neurological disorder complicating subjects with CKD. Uremic PNP (UPNP) arises when kidney dysfunction affects glomerular filtration, causing the accumulation of organic waste, which is usually attributed to end-stage renal disease (ESRD). We hypothesized that in uremic patients, hypovitaminosis D is correlated with PNP, thus this study aimed to assess the correlation of serum blood levels with incidence of UPNP. Materials and Methods: These 215 patients, cross-sectional observational study, involved 116 males and 99 females. The candidates had ESRD, evaluated and managed by qualified nephrologists, 17-80 years of age, being on regular weekly sessions of hemodialysis, for 3-4 hours/session 2-4sessions/week for the last 3-months. Blood samples of VitD (pg/ml) levels were taken from all the candidates. All cases had accomplished neurological examination in the hospital for the sensory and motor nerves and the presence and severity of PNP were assessed using "Baba’s classification". SPSS software was applied for statistical analyses. Results: The mean age of patients was (48.2±13.4) years, and the mean weight was (66.98 ± 12.87) kg. Nearly one-third of patients (N=76) had a duration of 1-3 years of hemodialysis, and only 36 patients had a duration of hemodialysis < 1 year. The majority of patients (N=183) had three times hemodialysis weekly, and only 5 patients had a frequency of hemodialysis four times per week. The prevalence of UPNP among uremic patients was 63.7% (N=137). There was a significant increase in the incidence and severity of UPNP with increasing age and decreasing levels of serum vitD. Conclusion: There was a highly significant decrease in the means of vitD3 serum levels in those with compared to those without UPNP (p-0.005), and the second is the highly significant decrease in the means of serum vitD3 levels with increasing severity of UPNP (p-0.004).