Bowel symptoms are associated with hypovitaminosis D in individuals with medically complicated obesity

We reported that 30% of individuals with medically complicated obesity have bowel symptoms, suggesting irritable bowel syndrome, but this prevalence of bowel symptoms is not related to body mass index or diabetes mellitus. Hypovitaminosis D is common in individuals with obesity and type 2 diabetes mellitus and is associated with depressive symptoms. Because antidepressants improve global symptoms in individuals with bowel symptoms, we hypothesize that the high prevalence of bowel symptoms in medically complicated obesity is associated with hypovitaminosis D. This is a single-institution, retrospective cohort study performed in a large, urban community teaching hospital. Over 2 years, individuals considering bariatric surgery completed a Manning symptom questionnaire to quantify bowel symptoms. Serum 25-hydroxy vitamin D was ordered, and the results were recorded for all individuals. Among 271 subjects, 229 subjects (80% women, 20% men; 67% black, 31% white; age range: 23-73 years; body mass index range: 35-91 kg/m²) completed 25-hydroxy vitamin D testing. Sixty-seven subjects (29%) have 3 to 6 Manning bowel symptoms, suggesting irritable bowel syndrome; 84 (37%) have type 2 diabetes; and 180 (79%) had vitamin D insufficiency. There are significant negative associations between Manning bowel symptoms and vitamin D concentrations in subjects with obesity (P = .01) and with type 2 diabetes mellitus and obesity (P = .007). The results support our hypothesis that the high prevalence of bowel symptoms in people with medically complicated obesity is associated with hypovitaminosis D. A prospective study is required to evaluate vitamin D supplementation and relief of bowel symptoms in people with medically complicated obesity.