The effects of vitamin D intake and status on symptom severity and quality-of-life in adults with irritable bowel syndrome (IBS): a systematic review and meta-analysis
Creators: name: Cara, Kelly C.
name: Taylor, Salima F.
name: Alhmly, Haya F.
name: Wallace, Taylor C.
Publisher: name: Taylor & Francis
Year: 2024
Subjects: Medicine
Biotechnology
Chemical Sciences not elsewhere classified
Science Policy
Mental Health

description: Many individuals with irritable bowel syndrome (IBS) have insufficient or deficient serum 25-hydroxyvitamin D [25(OH)D] status; however, it is not clear if improved vitamin D nutritional status through higher intake can improve symptom severity and quality of life. This systematic review and meta-analysis aimed to identify if changes in vitamin D intake or status affect symptom severity and quality of life in adults with IBS. <i>Data Sources:</i> MEDLINE<sup>®</sup>, Cochrane Central Register of Controlled Trials, Global Health, EMBASE, and Web-of-Science databases were systematically searched for relevant articles to August 12, 2024, in the English language. <i>Study Selection:</i> Clinical trials, prospective observational studies, and Mendelian randomization (MR) analyses reporting the effect of vitamin D intake or status on IBS-related outcomes were included. <i>Data Extraction and Synthesis:</i> Article review and data extraction were conducted by 2 authors following the PRISMA guidelines. Random effects meta-analyses and the Nutrition Quality Evaluation Strengthening Tools to assess risk of bias were employed for randomized controlled trials. <i>Main Outcome(s) and Measure(s):</i> Primary outcomes included measures of serum 25(OH)D status, symptom severity, and quality of life. 12 studies from 15 articles were included (<i>n</i> = 7 RCTs; <i>n</i> = 3 single-arm interventions; <i>n</i> = 2 MR). Seven study populations had deficient (&lt;20 ng/mL) and three had insufficient (21–29 ng/mL) baseline serum 25(OH)D status. RCTs measured changes in serum 25(OH)D after 6–26 wks with 3,000 IU daily to 50,000 IU bi-weekly vitamin D dosages. Meta-analyses of low risk-of-bias RCTs revealed increased 25(OH)D levels in groups treated with oral vitamin D compared to placebo (<i>n</i> = 5; Pooled mean difference [95% CI]: 20.33 [12.91, 27.74] ng/mL; <i>I</i><sup>2</sup> = 97.9%). Quality of life scores improved significantly in deficient populations (<i>n</i> = 3; 3.19 [2.14, 4.24]; <i>I</i><sup>2</sup> = 0.0%). Non-significant decreased trends in IBS symptom severity were shown across populations (<i>n</i> = 6: −25.89 [-55.26, 3.48]; <i>I</i><sup>2</sup> = 92.8%). Moderate level evidence indicate vitamin D supplementation may improve status in adults with IBS and quality of life in those with deficient status at baseline. Question: Do changes in vitamin D intake or status affect symptom severity and quality of life in adults with irritable bowel syndrome? FindingsIn this systematic review and meta-analysis, moderate level evidence supports vitamin D supplementation for improving serum 25-hydroxyvitamin D status in adults with IBS and for increasing quality of life scores in those with deficient status at baseline. Meaning: Vitamin D supplementation may improve quality of life in IBS patients with deficient serum 25-hydroxyvitamin D status.