Musculoskeletal pain: should physicians test for vitamin D level?

The aim of this study was to evaluate vitamin D levels using a reliable method in patients with regional and generalized musculoskeletal (MSK) pain in comparison to healthy controls.

A consecutive prospective case control cohort was recruited. Patients with generalized MSK pain, for example, fibromyalgia (FM), and regional MSK pain, for example, nonspecific low back pain (LBP) and knee osteoarthritis (OA) were screened for 25 hydroxy-vitamin D [25(OH)D₃ ] levels over a period of 9 months in a hospital-based setting.

One hundred and twenty-four patients and 82 age-sex matched controls were evaluated. The mean age for patients was 41.71 ± 13.86 years. Of the 124 patients, 118 (95%) were female, 77 (62.6%) had FM, 18 (14.6%) had LBP and 28 (22.8%) had knee OA. All patients had normal muscle power; 83.7% of females wore long garments, 11.4% wore veils, 95.5% had sun exposure < 10 min/day and 58.5% were multiparaous; 7.3% were strict vegetarians, 45.5% took inadequate dairy products. The mean calcium, parathyroid hormone, alkaline phosphatase and albumin levels were within normal limits for all study subjects. The vitamin D level was deficient in all patients. There was no statistical difference between the mean vitamin D values of the patients and controls, 27.61 ± 13.06 and 25.82 ± 15.06 nmol/L respectively, (P = 0.368).

Our findings suggest that it is unlikely that measuring vitamin D will be of diagnostic value in the routine assessment of regional and generalized MSK pain.