Journal of the American Chiropractic Association May 2010 by James Gerber
6 MAY-JUNE 2010 Nutritionally Speaking Vitamin D and Chronic Musculoskeletal Pain By James Gerber, MS, DC Surprising new roles for a vitamin previously associated only with calcium and bone metabolism include a potential role in treating chronic musculoskeletal pain. However, enthusiasm for using vitamin D routinely in the treatment of chronic pain should be tempered by its inconsistent record of effectiveness in clinical trials. Beginning with a 2003 report from an inner city primary care clinic in Minnesota that documented vitamin D deficiency in 93% of patients referred for evaluation of persistent non- specific musculoskeletal pain, this deficiency is increasingly recognized as an important differential in such patients. Also unexpected has been the high prevalence of vitamin D deficiency found recently in the general population, estimated to range from 21 to 58 percent depending on the demographics of the population studied. Reasons speculated for these disturbing statistics include low ultraviolet intensity at higher latitudes and during cooler seasons, less time spent out of doors without sunscreen, increasing populations of residents with darker skin pigmentation, which reduces ultraviolet penetration, age related changes in vitamin D production in the skin, reduced milk consumption, and many other factors. These developments have led to much interest in and debate over the use of vitamin D in patients with chronic musculoskeletal pain. A new case series appeared last year that holds special interest for doctors of chiropractic. The author, a Canadian family practitioner, describes six patients with chronic low-back pain who were given vitamin D supplements with varying degrees of success. Cases were de- scribed as associated with disc injuries, osteoarthritis, or nonspecific lumbar musculoskeletal pain. Three cases had histories of back surgery without long term benefit. Four of the cases had pre-treatment vitamin D blood levels determined, and were judged either deficient or insufficient in the vitamin. Each case was treated with sufficient vitamin D to establish blood levels in the upper end of normal laboratory values; this required from 1,000 to 5,000 IU per day. Four of these cases achieved complete resolution of their pain with no further need for pain medication in three cases. The other two cases had some improvement in pain but little change in need for pain medication. Sufficiently severe vitamin D deficiency is known to cause bone, muscle and joint pain, which can be confused with symptoms of fibromyalgia and other rheumatic diseases.However, some studies have not been able to correlate low vitamin D levels with chronic pain in large populations, and initial attempts to treat chronic pain syndromes with vitamin D have produced mixed results. While numerous case series studies have reported pain reduction after vitamin D supplementation in several types of chronic pain syndromes, double- blind randomized controlled trials (RCTs) have yielded largely negative results. Two RCTs found vitamin D ineffective when added to medical therapies, including anti-inflammatory medications, in patients with either polymyalgia rheumatic or rheumatoid arthritis, although the other therapies would likely have masked a modest benefit of vitamin D.
