The effect of vitamin D on nonspecific low back pain

Background Nonspecific low back pain is known as one of the most common reasons for chronic low back pain ( CLBP ) that burdens healthcare systems with high costs. According to a hypothesis, CLBP has been associated with vitamin D 3 deficiency, the goal of this study is to evaluate the effect of vitamin D 3 administration on improvements in CLBP . Materials and Methods This double blind randomized clinical trial included 53 patients aged between 18–40 years with nonspecific CLBP . Pain was measured using the pain visual analogue scale score ( VAS ), and serum 25‐ OH ‐vitamin D level was measured using an enzyme‐linked immunosorbent assay kit. The patients were randomly divided into two groups based on sex and weight. Pearl of vitamin D 3 (50 000 IU ) or placebo was administered orally every week for 8 weeks. Data were analyzed via SPSS 17th edition software using two‐tailed paired t ‐test and chi‐square test. Results There were 26 and 27 patients in drug and placebo groups respectively. Out of 53 subjects, 75.47% were female. There was no statistically significant difference in the mean age, sex, and mean weight between the two groups. The mean serum 25‐ OH ‐vitamin D level was 18.86 ± 9.24 nmol/L on the first visit. After 8 weeks of intervention, the mean serum 25‐ OH ‐vitamin D level changed from 17.88 ± 9.04 to 27.52 ± 9.04 ( P  = 0.043) and from 19.81 ± 9.60 to 18.91 ± 7.84 ( P  = 0.248) in drug and placebo groups, respectively. The mean VAS score for pain decreased from 5.42 ± 1.65 to 3.03 ± 3.14 ( P  = 0.001) and from 6.42 ± 1.62 to 3.11 ± 3.08 ( P  = 0.001) among drug and placebo groups, respectively. The mean changes in chronic pain were 2.38 ± 2.62, 95% confidence interval ( CI ) = 1.32–3.44 in the drug group and 3.33 ± 3.67, 95% CI  = 0.61–2.55 in the placebo group. No significant statistical difference between the two groups was observed. Conclusion According to our results, both vitamin D 3 and placebo treatments improved CLBP and there was no significant difference between vitamin D 3 and placebo groups.