Vitamin D is a significant micronutrient in muscle function. It is hypothesized that vitamin D deficiency may contribute to fecal incontinence (FI) symptoms by affecting the anal continence mechanism. The objective of this study was to characterize the association of vitamin D deficiency as a variable affecting FI symptoms and its impact on health-related quality of life (HR-QoL). This case-control study assessed women seen at a tertiary-care referral center. Participants were identified as having had a serum vitamin D level obtained within a year of their visit: cases were women presenting for care for FI symptoms; controls were women without any pelvic floor symptoms presenting to the same clinical site for general gynecologic care. Cases completed the Modified Manchester Health Questionnaire (MMHQ) and the Fecal Incontinence Severity Index to measure symptom severity and burden on QoL. Among the 31 cases and 81 controls, no demographic or medical differences were present. Women with FI had lower vitamin D levels (mean 29.2 ± 12.3 cases vs. 35 ± 14.1 ng/ml controls p = 0.04). The odds of vitamin D deficiency were higher in women with FI in comparison to controls [odds ratio (OR) 2.77, 95 % confidence interval (CI) 1.08-7.09]. Among cases, women with vitamin D deficiency (35 %) had higher MMHQ scores, indicating greater FI symptom burden [51.3 ± 29.3 (vitamin D deficient) vs. 30 ± 19.5 (vitamin D sufficiency), p = 0.02]. No differences were noted for FI severity, p = 0.07.
Vitamin D deficiency is common in women with fecal incontinence and could contribute to patient symptom burden.