title: The effect of vitamin D on nonspecific low back pain.
abstract: 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 D3 deficiency, the goal of this study is to evaluate the effect of vitamin D3 administration on improvements in CLBP.
  
  
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Internal Medicine, Ali-Ebne-Abitaleb Hospital, Zahedan University of Medical Sciences, Zahedan, Iran.
authors.forename: Mahnaz
authors.initials: M
authors.lastname: Sandoughi
authors.affiliation: Department of Internal Medicine, Ali-Ebne-Abitaleb Hospital, Zahedan University of Medical Sciences, Zahedan, Iran.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Zakeri
authors.affiliation: Department of Internal Medicine, Ali-Ebne-Abitaleb Hospital, Zahedan University of Medical Sciences, Zahedan, Iran.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Mirhosainee
authors.affiliation: Biostatistics, Health promotion research center, Zahedan University of Medical Sciences, Zahedan, Iran.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Mohammadi
authors.affiliation: Tehran University of Medical Sciences (TUMS), Tehran, Iran.
authors.forename: Sogol
authors.initials: S
authors.lastname: Shahbakhsh
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood; D016009:Chi-Square Distribution; D002762:Cholecalciferol / Q000008:administration & dosage* / Q000009:adverse effects; D019587:Dietary Supplements; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007492:Iran; D017116:Low Back Pain / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control*; D008297:Male; D010147:Pain Measurement; D013997:Time Factors; D016896:Treatment Outcome; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D014807:Vitamin D; D002762:Cholecalciferol; C104450:25-hydroxyvitamin D
keywords: low back pain; pain; vitamin D3