Vitamin D Supplementation in Patients with Chronic Low Back Pain: An Open Label, Single Arm Clinical Trial

Background: Vitamin-D deficiency may possibly be related to chronic low back pain (CLBP). Objective: The study is aimed to assess the impact of vitamin-D supplementation on pain intensity, functional disability, and vitamin-D levels in patients with CLBP. Study Design: Single arm open-label study. Setting: Outpatient pain clinic of a tertiary care hospital. Methods: Sixty-eight eligible patients (CLBP for >= 3 months, pain score >= 50 on visual analogue scale (VAS) and plasma 25-Hydroxyvitamin D3 levels < 30 ng/mL) were enrolled. Patients were supplemented with 60,000 IU of oral vitamin-D3 given every week for 8 weeks. Efficacy parameters included pain intensity and functional disability measured by VAS and modified Oswestry disability questionnaire (MODQ) scores at baseline, 2, 3, and 6 months post-supplementation. Plasma 25(OH) D3 levels were measured at baseline and 8 weeks. Results: Baseline mean (SD) vitamin-D levels were 12.8 (5.73) ng/mL and increased to 36.07 (12.51) post supplementation (P < 0.01). Forty-five (66%) patients attained normal levels (> 29 ng/mL) post supplementation. Significant reduction in VAS was observed at 2, 3, and 6 months [61 (19), 45 (19), 36 (18)] as compared to 81 (19) at baseline (P <= 0.001 at all-time intervals). A significant improvement in the functional ability was also observed at 2, 3, and 6 months [36 (12), 31 (13), and 26 (10)] as compared to baseline 45 (16) (P <= 0.001 at all-time intervals). Conclusion: Vitamin-D supplementation in deficient CLBP patients may lead to improvement in pain intensity and functional ability apart from normalization of the levels. Future controlled clinical trials are required to confirm the hypothesis.