In particular, those with high-risk sexual activity, such as engaging in unprotected sex or having multiple sexual partners, were more likely to have IBD diagnoses than men who have sex with women who also have high-risk sexual activity.
“Underrepresented sex and gender minorities have less access to healthcare in general for multiple reasons, and when it comes to gastrointestinal issues, such as IBD, there may be a certain level of shame when going to a doctor or clinic,” senior author Fabio Cominelli, MD, PhD, told Medscape Medical News. Cominelli is a professor of medicine and pathology at Case Western Reserve University and the chief scientific officer of the Digestive Health Institute at University Hospitals Cleveland Medical Center.
“Our overall goal is to improve access to healthcare so people can access all of the resources available,” he said. “If we can learn more about the pathogenesis, or cause of the disease, we can help with diagnosis and treatment.”
The study was published online in the BMJ journal Gut.
The prevalence and natural history of IBD hasn’t been reported for lesbian, gay, bisexual, transgender, queer, intersex, and asexual populations, the study authors write. As of 2022, 7% of Americans identify as LGBTQIA+, up from 5.6% in 2020, according to a Gallup poll from earlier this year, highlighting the importance of understanding the epidemiology of IBD for these patients.
Cominelli and colleagues analyzed data from TriNetX, a large population-based health research network, to evaluate the prevalence of Crohn’s disease and ulcerative colitis in LGBTQIA+ groups between 2002 and 2022. They first identified adult patients based on self-reported sexual orientation, and then further defined those with a diagnostic code of high-risk sexual activity.
Among 11,845 people with high-risk, same-sex sexual activity, 91 (0.77%) were diagnosed with Crohn’s disease and 148 (1.3%) were diagnosed with ulcerative colitis. About 91% were men, and among those who have sex with men, 86 people (0.8%) were diagnosed with Crohn’s disease and 136 people (1.3%) were diagnosed with ulcerative colitis.
Among the 498 women with high-risk, same-sex sexual activity, 5 were diagnosed with Crohn’s disease and 8 were diagnosed with ulcerative colitis. The research team excluded women from the analysis because of a lack of statistical power.
Among the 60,755 men who have sex with women with high-risk sexual activity, 298 (0.49%) had Crohn’s disease and 314 (0.52%) had ulcerative colitis.
Overall, men who have high-risk sex with men were nearly 2.5 times more likely to be diagnosed with ulcerative colitis and 64% more likely to be diagnosed with Crohn’s disease.
“We hope this retrospective study provides a starting point for us and others to do prospective studies where we enroll patients and more closely investigate this idea,” Cominelli said. “Our goal is to develop personalized precision therapy for patients.”
Hypotheses Accounting for the Higher Prevalence
Cominelli and colleagues have received grants from the National Institutes of Health to confirm the increased prevalence of IBD in men who have sex with men, as well as the association between specific sexual practices and the risk of developing Crohn’s disease or ulcerative colitis.
They’re also investigating the potential role of the gut microbiome, with the aim of developing interventions for patients.
“One hypothesis is that sexual preferences and practices — such as anal sex or oral sex — can predispose people to specific infections,” Cominelli said. “Some studies, especially among HIV patients, have provided some preliminary evidence that the gut microbiome can be different and may play a role in IBD, which can affect the prevalence of disease.”
For instance, previous studies have shown that men who have sex with men predominantly have a Prevotella-rich enterotype, whereas other groups have a Bacteroides-rich enterotype. Men who have sex with men also have a significantly richer and more diverse fecal microbiome composition, the study authors write.
In addition, researchers and clinicians should consider the possibility of sexual transmission of specific fecal organisms between men who have sex with men, they write. Several studies have found an increased prevalence of invasive infections by Entamoeba histolytica, Shigella, Cryptosporidia, and Campylobacter among men who have sex with men.
Future Studies Needed to Address Limitations
Even still, additional studies are needed to understand the prevalence rates of IBD among LGBTQIA+ patients and how certain sexual practices may influence the gut microbiome, Adam Ehrlich, MD, associate professor of medicine at Temple University, Philadelphia, Pennsylvania, told Medscape Medical News.
“The challenge here is that using a large database has lots of challenges with bias,” he said. “For example, there are very small numbers of LGBTQIA+ patients with IBD in this analysis, there is no specific definition for ‘high-risk activity’ for either homosexual or heterosexual practices, and racial breakdown includes many of unknown race.”
Ehrlich, who also serves as co-medical director of Temple University Hospital’s Inflammatory Bowel Disease Program, is one of the gender-affirming gastroenterologists at the hospital.
“These database studies are often good to generate hypotheses that can be better analyzed with a cohort of patients that you know more about,” Ehrlich said. “Are patients who identify as LGBTQIA+ more susceptible to IBD? If so, what would the mechanism be? Further study is needed, as they suggest.”
The study was supported by the Clinical Component of the Administrative Core of the NIH Cleveland Digestive Diseases Research Core Center and administrative supplement from the National Institute of Diabetes and Digestive and Kidney Diseases and Sexual and Gender Minority Research Office. The authors and Ehrlich report no relevant financial relationships.
Gut. Published online September 1, 2022. Abstract
Carolyn Crist is a health and medical journalist who reports on the latest studies for Medscape, MDedge, and WebMD.