PT  - JOURNAL ARTICLE
AU  - Azali, Payam
AU  - Barbasso Helmers, Sevim
AU  - Kockum, Ingrid
AU  - Olsson, Tomas
AU  - Alfredsson, Lars
AU  - Charles, Peter J
AU  - Piehl Aulin, Karin
AU  - Lundberg, Ingrid E
TI  - Low serum levels of vitamin D in idiopathic inflammatory myopathies
AID  - 10.1136/annrheumdis-2012-201849
DP  - 2013 Apr 01
TA  - Annals of the Rheumatic Diseases
PG  - 512--516
VI  - 72
IP  - 4
4099  - http://ard.bmj.com/content/72/4/512.short
4100  - http://ard.bmj.com/content/72/4/512.full
SO  - Ann Rheum Dis2013 Apr 01; 72
AB  - Objectives To evaluate serum levels of 25(OH) vitamin D in patients with idiopathic inflammatory myopathies (IIM) (polymyositis (PM), dermatomyosistis (DM), inclusion body myositis (IBM) and juvenile DM (JDM)) and to compare these with healthy controls. Methods Serum samples from 149 patients with IIM and 290 healthy controls matched for gender and the month of blood sampling were analysed for 25(OH) vitamin D. ORs for vitamin D classes with 95% CI were calculated using a matched (conditional) logistic regression model. Groups were compared by the Kruskal–Wallis test and p values <0.05 were considered significant. Results Patients with IIM had significantly lower serum levels of 25(OH) vitamin D than healthy controls (median 39 (10–168) nmol/l vs 68 (19–197) nmol/l; p=0.0001). There was no significant difference in vitamin D levels between the myositis subgroups. When vitamin D levels were subclassified into deficient (<50 nmol/l), insufficient (50–74 nmol/l) and normal (≥75 nmol/l), most of the patients with PM (68%), DM (65%) and IBM (53%) had deficient levels compared with only 60 (21%) healthy individuals. In patients with IIM the OR for deficient versus normal was 17.7 (95% CI 8.1 to 38.6) and the OR for insufficient versus normal was 2.4 (95% CI 1.2 to 4.7). Conclusions Low serum levels of vitamin D were found in most patients with IIM and may confer a risk factor for developing adult myositis, similar to some other autoimmune diseases.