Associations Between Sexual Orientation and Disorders of Gut-Brain Interaction in Sexual Minority Populations.

Background & aims: Sexual and gender minority (SGM) individuals (e.g., those identifying as Lesbian, Gay, Bisexual, Transgender, Queer or Other [LGBTQ+]) are disproportionately affected by psychological distress and trauma, all recognized risk factors for disorders of gut-brain interaction (DGBIs). This suggests a potentially higher burden of DGBIs in SGM populations. However, the relationship between SGM status and DGBIs has not been well characterized in large-scale clinical datasets.

Methods: We conducted a retrospective, cross-sectional analysis using All of Us database to identify the relationship between sexual orientation and presence of bowel DGBIs. Eligible participants were adults (≥18 years) who completed a sexual orientation survey and had gastrointestinal diagnostic data available. Participants self-identified as straight, gay or lesbian, or bisexual. Outcomes included irritable bowel syndrome (IBS), functional diarrhea, and chronic constipation, identified using ICD-10 codes. Chi-square tests and multivariable logistic regression models were used to assess associations between sexual orientation and DGBIs, stratified by gender and adjusted for demographic, socioeconomic, and psychological factors. Interaction analyses were conducted to assess whether the association between sexual orientation and DGBIs differs between men and women. Missing data were imputed using multiple imputation by chained equations (MICE) to address missing covariate data under a Missing at Random (MAR) assumption, and sensitivity analyses with pooled results were compared with complete-case analyses to support robustness.

Results: Among 386,242 eligible participants, 3.58% (n=13,843) identified as gay or lesbian, and 4.09% (n=15,788) as bisexual. Gay or bisexual men had significantly higher odds of being diagnosed with IBS (aOR 1.55, 95%CI 1.36-1.76), functional diarrhea (aOR 1.82, 95%CI 1.36-2.38), chronic constipation (aOR 1.33, 95%CI 1.08-1.63), and a composite DGBI outcome of any of these diagnoses (aOR 1.49, 95%CI 1.33-1.66) compared to straight men. Among women, there were no statistically significant associations between sexual orientation and any of the DGBI diagnoses or the composite outcome. Interaction analyses demonstrated that these associations were significantly stronger among men, particularly for any DGBI, functional diarrhea, and IBS.

Conclusions: Sexual orientation was independently associated with DGBI diagnoses among men, with no significant associations observed among women. These findings underscore the importance of considering gender-specific patterns when evaluating gastrointestinal health in sexual minority populations and highlight the need for tailored, inclusive approaches to DGBI care and research.