PT  - JOURNAL ARTICLE
AU  - Janssens, Wim
AU  - Bouillon, Roger
AU  - Claes, Bart
AU  - Carremans, Claudia
AU  - Lehouck, An
AU  - Buysschaert, Ian
AU  - Coolen, Johan
AU  - Mathieu, Chantal
AU  - Decramer, Marc
AU  - Lambrechts, Diether
TI  - Vitamin D deficiency is highly prevalent in COPD and correlates with variants in the vitamin D-binding gene
AID  - 10.1136/thx.2009.120659
DP  - 2010 Mar 01
TA  - Thorax
PG  - 215--220
VI  - 65
IP  - 3
4099  - http://thorax.bmj.com/content/65/3/215.short
4100  - http://thorax.bmj.com/content/65/3/215.full
SO  - Thorax2010 Mar 01; 65
AB  - Introduction Vitamin D deficiency has been associated with many chronic illnesses, but little is known about its relationship with chronic obstructive pulmonary disease (COPD).Objectives Serum 25-hydroxyvitamin D (25-OHD) levels were measured in 414 (ex)-smokers older than 50 years and the link between vitamin D status and presence of COPD was assessed. The rs7041 and rs4588 variants in the vitamin D-binding gene (GC) were genotyped and their effects on 25-OHD levels were tested.Results In patients with COPD, 25-OHD levels correlated significantly with forced expiratory volume in 1 s (FEV1) (r=0.28, p<0.0001). Compared with 31% of the smokers with normal lung function, as many as 60% and 77% of patients with GOLD (Global Initiative for Obstructive Lung Disease) stage 3 and 4 exhibited deficient 25-OHD levels <20 ng/ml (p<0.0001). Additionally, 25-OHD levels were reduced by 25% in homozygous carriers of the rs7041 at-risk T allele (p<0.0001). This correlation was found to be independent of COPD severity, smoking history, age, gender, body mass index, corticosteroid intake, seasonal variation and rs4588 (p<0.0001). Notably, 76% and 100% of patients with GOLD stage 3 and 4 homozygous for the rs7041 T allele exhibited 25-OHD levels <20 ng/ml. Logistic regression corrected for age, gender and smoking history further revealed that homozygous carriers of the rs7041 T allele exhibited an increased risk for COPD (OR 2.11; 95% CI 1.20 to 3.71; p=0.009).Conclusion Vitamin D deficiency occurs frequently in COPD and correlates with severity of COPD. The data warrant vitamin D supplementation in patients with severe COPD, especially in those carrying at-risk rs7041 variants.