BACKGROUND AND OBJECTIVE: Chronic musculoskeletal pain may  persist for more than three months and is often resistant to treatment. The aim of this study was to examine the relationship between chronic musculoskeletal pain and vitamin D deficiency in the elderly population of Amirkola, Iran.

METHODS: This cross-sectional study was part of a health survey on the elderly population of Amirkola (AHAP=Amirkola Health and Ageing Project), including 1616 senior citizens, aged ≥ 60 years. Overall, 857 individuals without rheumatoid arthritis, cancer, depression, diabetes or osteoarthritis were enrolled in this study. Demographic data were collected and a questionnaire on chronic musculoskeletal pain was applied. The anatomical site of pain was determined by inquiring the elderly. The serum level of vitamin D was measured in two groups with and without chronic pain, using the ELISA method. Vitamin D deficiency, insufficiency and sufficiency were defined as serum vitamin D levels of < 20, 20-29.99 and ≥30 ng/ml, respectively.

FINDINGS: Among 857 participants, 599 (69.9%) and 258 (30.1%) cases were male and female, respectively. Moreover, 666 participants (77.7%) complained of chronic pain. The most common sites of pain were the knees (54%), back (40%), feet (35.7%) and shoulders (27.5%), respectively. Also, 41.9% of the elderly had vitamin D deficiency. However, vitamin D level was not significantly different between the two groups (with and without chronic pain), and frequency of chronic pain did not significantly vary between these groups. Based on the logistic regression model, gender (OR=2.73, 95%CI=1.78-4.21, p=0.001), body mass index and physical activity (OR=0.42, 95% CI=0.28-0.62, p=0.001) had significant impacts on chronic pain.

CONCLUSION: The results showed no significant relationship between vitamin D level and chronic musculoskeletal pain in the elderly population of Amirkola, Iran.