Correlation of symptoms with vitamin D deficiency and symptom response to cholecalciferol treatment: a randomized controlled trial.
OBJECTIVE
To examine the association of symptoms with vitamin D deficiency and symptom response to cholecalciferol treatment in a randomized, double-blind, placebo-controlled trial.


METHODS
Adult primary care patients in Duluth, Minnesota, were screened for vitamin D deficiency in February 2007. Participants completed questionnaires pertaining to a variety of symptoms, vitamin D intake, and selected medical conditions. Patients with mild to moderate vitamin D deficiency (25-hydroxyvitamin D [25(OH)D], 10-25 ng/mL) participated in a randomized controlled trial (RCT) of vitamin D replacement and its effect on symptoms. Participants were randomly assigned to receive 50 000 units of cholecalciferol (vitamin D3) weekly or placebo for 8 weeks. Patients with severe vitamin D deficiency (25[OH]D <10 ng/mL) were treated in an unblinded fashion, and symptoms were reevaluated post treatment.


RESULTS
A total of 610 patients underwent initial screening, and 100 patients with mild to moderate vitamin D deficiency participated in the RCT. Thirty-eight severely deficient patients were treated in an unblinded fashion. On initial screening, 46.2% of participants were deficient in vitamin D. Self-reported vitamin D supplementation, milk intake, celiac disease, gastric bypass, and chronic pancreatitis were predictive of vitamin D status. Severely deficient participants reported increased musculoskeletal symptoms, depression (including seasonal), and higher (worse) scores on a fibromyalgia assessment questionnaire. In the RCT, the treated group showed significant improvement in fibromyalgia assessment scores (P = 0.03), whereas the placebo-treated participants did not. Severely deficient patients did not show symptom improvement over the 8-week trial period or when followed up 1 year later.


CONCLUSIONS
Compared with participants in the placebo group, patients in the treatment group showed mild short-term improvement in the overall fibromyalgia impact score, but did not show significant improvement in most musculoskeletal symptoms or in activities of daily living.
St Luke's Internal Medicine Associates, Duluth, Minnesota 55802, USA. DArvold@slhduluth.com
David S
DS
Arvold
Marilyn J
MJ
Odean
Maude P
MP
Dornfeld
Ronald R
RR
Regal
Judith G
JG
Arvold
Gene C
GC
Karwoski
David J
DJ
Mast
Paul B
PB
Sanford
Robert J
RJ
Sjoberg
D000328:Adult; D000368:Aged; D000465:Algorithms; D054316:Biomarkers, Pharmacological / Q000032:analysis*; D002112:Calcifediol / Q000097:blood; D002762:Cholecalciferol / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010919:Placebos; D011379:Prognosis; D012307:Risk Factors; D011795:Surveys and Questionnaires; D016896:Treatment Outcome; D014808:Vitamin D Deficiency / Q000097:blood / Q000175:diagnosis* / Q000188:drug therapy* / Q000209:etiology
D054316:Biomarkers, Pharmacological; D010919:Placebos; D002762:Cholecalciferol; D002112:Calcifediol