P121. Vitamin D deficiency in Crohn's disease Portuguese patients: prevalence and risk factors
R. Cerqueira1, M. Correia2, C. Fernandes2, C. Manso3, 1S Sebastiao Hospital, Gastroenterology, Porto, Portugal, 2S Sebastiao Hospital, Portugal, 3University Fernando Pessoa, Biostatistics, Porto & REQUIMTE-UP, Portugal
Vitamin D deficiency is highly prevalent worldwide. It is even more common in specific risk groups as adolescents and young adults, and patients with malabsorption, which are typical features of Crohn's disease. Besides its well known role in bone health through calcium and phosphorus homeostasis regulation there is increasing evidence of anti-inflammatory and anti-cancer roles in the gut. However, its prevalence has never been assessed in Portuguese patients. The aim of this single center study was to assess the prevalence and risk factors of Crohn's disease patients in an outpatient setting.
We conducted a cross-sectional study by going through the clinical records of 61 Crohn's disease patients who had undergone a serum 25(OH)D assessment. Their average age was 36.1 years (±12) and 31 (50.8%) were female. Serum 25-hydroxyvitamin D [(25(OH)D] was determined by radioimmunoassay and levels of <30 ng/ml were considered deficient. Summer season was classed as the time period from April to October. Univariate analysis was performed using the chi-square test and the independent effect of significant variables (p < 0.05) was assessed using multivariate logistic regression analysis (Wald backward stepwise method).
The prevalence of 25(OH)D deficiency was 69.7% (37 patients). Mean Summer 25(OH)D levels were significantly higher than Winter ones (34.4±19.2 vs 23±20.8, p < 0.002). On univariate analysis 25(OH)D deficiency was associated with Winter season (OR = 6.24; 95% CI:1.90–20.48, p = 0.002) and no physical exercise (OR = 7.7; 95% CI=1.67–35.5, p = 0.005). There was a trend association with more than 60 months disease lenght (OR = 7.5; 95% CI:1.53–36.75, p = 0.006). On multivariate analysis Winter season and physical exercise remained significantly associated. Applying a receiver operating characteristic (ROC) analysis, the area under the curve (AUC) derived from a model including Winter season and no physical exercise was 0.84 (95% CI:0.72–0.95) for 25(OH)D deficiency in Crohn's disease patients.
Vitamin D deficiency was common in Crohn's disease patients and was associated with absence of physical exercise and winter time.
As serum 25(OH)D were frequently below levels assumed to maintain bone homeostasis balance and modulate inflammation, its levels must be measured on a regular basis to identify patients in need for pharmacological vitamin D supplementation in winter or all year long.