The effect of vitamin D levels on gastrointestinal bleeding in patients with warfarin therapy

Upper tract gastrointestinal system (GIS) bleeding is considered as an important cause of morbidity and mortality despite modern and advanced endoscopic interventions. In patients with thrombotic state and vitamin D deficiency, vitamin D analogs and vitamin D receptor activators have been determined as adjunctive anticoagulant treatment in previous studies. However, these studies did not evaluate or reveal the possible bleeding diathesis. In this article, we evaluated the vitamin D status in patients with warfarin treatment and upper tract GIS bleeding. A total of 75 patients with a definite diagnosis of upper tract GIS bleeding who had a treatment of warfarin and current vitamin D measurement; and a total of 75 control patients without any recent or prior GIS bleeding who had a treatment of warfarin and current vitamin D measurement were enrolled to the study. GIS bleeding group had a proportionally higher vitamin D treatment (29.3 vs. 17.3%). In GIS bleeding group, the prevalence of vitamin D level less than 20 ng/ml was significantly lower (66.7 vs. 82.7%; P = 0.024) and the prevalence of vitamin D level at least 30-100 ng/ml was significantly higher (25.3 vs. 10.7%; P = 0.019). According to a subgroup analysis; in patients with a vitamin D level at least 30-100 ng/ml, major bleeding rate was significantly higher compared with other patients. There was not a significant difference regarding mortality between the groups. Our study is the first which represents the possible bleeding effect of elevated vitamin D levels and vitamin D treatment in patients with warfarin treatment.