Risk factors for vitamin D deficiency in patients with Crohn’s disease

Background Although the pathogenesis of osteopenia in Crohn’s disease is not established, vitamin D deficiency is thought to be an important risk factor. However, little is known about the prevalence of vitamin D deficiency in patients with Crohn’s disease in Japan. This study aimed to clarify the prevalence of vitamin D deficiency in patients with Crohn’s disease in Japan and to examine the possible causes of the deficiency.