Vitamin D deficiency among inflammatory bowel disease patients in Argentina : a cross-sectional study

Background – An association has been established between low serum values of vitamin D and inflammatory bowel disease. There is a lack of evidence on whether this association is still observed in regions where sun exposure throughout the year is higher. Objective – To compare the prevalence of vitamin D deficiency between inflammatory bowel disease patients and healthy controls. Methods – Inflammatory bowel disease patients were consecutively enrolled as cases. Age and gender-matched healthy subjects who agreed to undertake a determination of serum vitamin D were enrolled as controls. Demographic features, medical treatment, need for hospital admission at diagnosis, steroid treatment, smoking, need for surgical treatment were evaluated as factors associated with vitamin D deficiency. Results – Overall, 59 patients with a diagnosis of either Crohn’s disease or ulcerative colitis were enrolled, as well as 56 controls. Median age was 41 years (19-79) and 56% were male. Vitamin D deficiency was observed in 66.1% of inflammatory bowel disease patients versus 21.42% of healthy controls (OR 7.15 (3.1-16.48), P=0.001). Among inflammatory bowel disease patients, male gender, disease duration, moderate-to-severe disease and hospital admission at the moment of diagnosis were found to be associated with vitamin D deficiency. On multivariate analysis, only longer disease duration [(OR 1.01 (1-1.06)] and hospital admission at diagnosis [(OR 5.63 (1.01-31.61)] were found to be significantly associated with the latter. Conclusion – Vitamin D deficiency was more frequent among inflammatory bowel disease patients. Longer disease duration and need for hospital admission at diagnosis were associated to vitamin D deficiency among these patients. HEADINGS – Ulcerative colitis. Crohn’s disease. Vitamin D. Declared conflict of interest of all authors: none Disclosure of funding: no funding received Gastroenterology Department, Hospital Británico de Buenos Aires, Buenos Aires, Argentina. Corresponding author: Juan Lasa. Orcid: 0000-0003-0957-5591. E-mail: drjuanslasa@gmail.com terms of the magnitude of the inflammatory response observed among IBD patients. For instance, there seems to be a correlation between vitamin D3 values in serum and the severity of the inflammatory response among CD patients(6). This correlation has also been observed among UC patients. As it is known, vitamin D3 activity is related to solar exposure(7). Most of the evidence regarding vitamin D3 and IBD comes from Northern Hemisphere countries, in which solar exposure and thus vitamin D deficiency can be a prevalent condition. Coincidentally, IBD incidence is slightly higher in many countries from the Northern Hemisphere than from the Southern Hemisphere. There is also a lack of local evidence regarding the prevalence of vitamin D deficiency among IBD patients and possible risk factors that could be potentially associated with vitamin D deficiency. Hence, we sought to compare vitamin D3 serum values between a cohort of IBD patients versus healthy volunteers and to determine which clinical features among IBD patients were linked to a higher odds of low vitamin D values.