Vitamin D Deficiency Associated With Increased Osteoarthritis Symptoms and Reduced Pain Threshold
HONOLULU, HI—Study investigators presented data from the UPLOAD (Understanding Pain & Limitations in OsteoArthritic Disease) study at the American Pain Society's 31st Annual Scientific Meeting demonstrating that hydroxyvitamin D levels <25ng/mL were associated with an increase in osteoarthritis (OA) symptoms and a decreased threshold for pressure pain.
A clinically meaningful threshold value associating vitamin D levels and chronic pain outcomes has yet to be determined. Experts conservatively suggest that hydroxyvitamin D levels <10ng/mL denote severe deficiency, 10–19ng/mL indicate moderate insufficiency, and 20–29ng/mL signify mild insufficiency. Toni Glover, MSN, ARNP, FNP-BC, from the
A total of 155 patients with chronic knee pain, regardless of radiographic evidence of OA were recruited. Patient demographics were 73% female, mean age of 56 years, and racially diverse (48% African Americans/Blacks and 52% Whites). Upon radiographic exam of the knees, 67% of participants had Kellgren-Lawrence OA scores from 2–4 (mild to severe). Total serum vitamin D was obtained by high performance liquid chromatography (total 25-hydroxyvitamin D= 25(OH)D2 + 25(OH)D3). Of the patients, 73% had vitamin D levels <30ng/mL and 9% had severe deficiency at <10ng/mL. Vitamin D supplementation of <1000 IU/day was taken by 28%, 20% supplemented with >1000 IU/day, and 52% did not supplement.
Patients completed the
Using the Short Performance Physical Battery (SPPB), patients were evaluated on their ability to perform balance tests, stand up from sitting in a chair, and walk a 4-meter timed course. There were non-significant main effects of vitamin D level <25ng/mL and BMI >30 on SPPB score, however, there was a significant interaction effect (P<0.01). Thus, investigators stated, if the vitamin D level was <25ng/mL and the BMI was >30, patients had worse lower extremity function as measured by SPPB.
These findings demonstrate that low levels of vitamin D are associated with chronic knee pain and that levels <25ng/mL may be used as a clinical threshold to treat vitamin D insufficiency with the goal of mitigating chronic pain, concluded Dr. Glover.