Active vitamin D (1,25 dihydroxyvitamin D) is associated with chronic pain in older Australian men: the Concord Health and Ageing in Men Project.

Background: Although there is a conflicting evidence for an association between low serum 25-hydroxyvitamin D (25D) levels and pain, the relationship between pain and the active vitamin D metabolite, 1,25-hydroxyvitamin D (1,25D), has not been investigated. The aim of this study was to examine the associations between serum vitamin D metabolites: 25D and 1,25D with intrusive or chronic pain in community-living men aged ≥70 years.

Methods: Population-based, cross-sectional analysis of the baseline phase of the Concord Health and Ageing in Men Project, a large epidemiological study conducted in Sydney between January 2005 and May 2007. Participants included 1,659 community dwelling men aged ≥70 years, taking part in Concord Health and Ageing in Men Project. Main outcome measurements were symptoms of chronic or intrusive pain. Covariates included 25D and 1,25D, parathyroid hormone, estimated glomerular filtration rate as well as age, country of birth, season of blood collection, body mass index, health conditions, and medication, including nonsteroidal anti-inflammatory drugs and statins.

Results: The prevalence of intrusive pain was 22.9% and of chronic pain was 29.7%. Low serum 25D concentrations were associated with intrusive and chronic pain in unadjusted analysis, but after adjustment, the associations were no longer significant. Low 1,25D levels (<62.0 pmol/L) remained independently associated with chronic pain (odds ratio: 1.53 [1.05, 2.21, p = .02]), even after adjustment for a wide range of potential confounders and covariates of clinical significance.

Conclusions: Low serum 1,25D concentrations are associated with chronic pain in older men. This raises the question whether vitamin D metabolites may influence pain states, mediated through different biological mechanisms and pathways.