Objectives: Identified etiological factors for chronic widespread pain (CWP) are largely related to emotional and behavioral factors, but current management leads to modest improvement in symptoms. Vitamin D deficiency has been suggested as a novel modifiable risk factor for CWP. We examine the association between vitamin D status [measured by 25(OH)D] and CWP in a nationwide population sample of white British adults, accounting for potential mediating and confounding lifestyle factors.
Methods: 9377 participants born one week in March, 1958, in England, Scotland or Wales and completing a biomedical assessment at age 45; 6824 eligible participants had data on 25(OH)D and completed pain manikins.
Results: Prevalence of CWP varied by 25(OH)D concentration in women but not in men, with the lowest prevalence observed for females with 75-99 nmol/l (14.6% for <25nmol/l, 14.7% for 25-49 nmol/l, 11.5% for 50-74nmo/l, 7.7% for 75-99 nmol/l, and 9.7% for participants with >100nmol/l). There was an interaction between 25(OH)D concentration and gender in relation to CWP (interaction, p=0.006), which was not fully explained by differences in lifestyle or social factors, adjusted interaction, p= 0.03). For women, the association between 25(OH)D concentration and CWP persisted after full adjustment (OR for <75nmol/l vs. 75-99 nmol/l 1.57, 95%CI 1.09, 2.26), while no evidence for an association was apparent in men (1.03, 0.75, 1.43).
Conclusion: Current vitamin D status was associated with CWP in women but not in men. Follow-up studies are needed to evaluate whether higher vitamin D intake could have beneficial effects on CWP risk.