Background:
Chronic pain diagnosis and management is a common and one of the most challenging encounters in occupational medicine practice.

Job-related strains and sprains may constitute a common etiology of musculoskeletal pain in the workplace and most patients respond to usual management; however, some do not respond favorably and challenge our diagnostic and therapeutic skills, and some don’t have a clear etiology.

Interestingly, our feature article “Prevalence and Clinical Correlates of Vitamin D Inadequacy among Patients with Chronic Pain” in Pain Medicine 2008 vol. 9 reports a correlation between diminished serum vitamin D levels and chronic pain.

Dr. Michael Hooten and his colleagues of Mayo Clinic studied 267 chronic pain patients who were referred to the Mayo Comprehensive Pain Rehabilitation Center using retrospective case series. A prevalence of Vitamin D inadequacy among chronic pain patients was identified with this study. They found a significant increase in therapeutic opioid dosage and duration of use in patients with decreased vitamin D levels. Their subscale scores also showed significant poorer health perception and worse physical functioning.

Although adequate for a prevalence study and providing valuable indications for associating factors, the cross-sectional method can not be used to draw conclusion for causal relations. As the article indicated some of the limitations itself, because of the potential selections bias, the external validity could also be a question when applying the result to general chronic pain patient.

In the clinical setting when dealing with chronic pain patients, especially those not responding to conventional methods, it may be useful to consider other contributing factors that may be associated with or delay the optimal recovery.