Anxiety and irritable bowel syndrome may each be associated with more than a twofold increase in the likelihood of a subsequent diagnosis of the other condition compared with controls, according to a recent study.
In the retrospective cohort study, investigators used the TriNetX Global Collaborative Network, which aggregates de-identified electronic health records from more than 100 health care organizations, primarily in the United States. Adult patients aged 18 years or older with diagnoses of anxiety disorders, irritable bowel syndrome (IBS), or inflammatory bowel disease (IBD) recorded between January 1, 2021, and January 1, 2024, were eligible. Separate exposure cohorts were created to evaluate risk in both temporal directions. To reduce confounding and ensure temporal clarity, the patients were excluded if they had prior psychiatric disorders; gastrointestinal (GI) disease; recent GI infections; or documented exposure to antidepressants, benzodiazepines, sedative-hypnotics, antipsychotics, or opioids. Diagnoses were identified using International Classification of Diseases, Tenth Revision codes. Propensity score matching was performed using age, sex, race, ethnicity, smoking status, and history of depressive episodes, resulting in balanced exposure and control cohorts.
After matching, the anxiety analysis included 601,315 patients with anxiety and an equal number of matched controls. After a follow-up period of up to 5 years, 1.1% of the patients with anxiety developed IBS compared with 0.4% of controls. Anxiety preceded IBD slightly more often compared with in matched controls, although absolute incidence was low in both groups. Associations between anxiety and IBD were weaker and asymmetric, with anxiety modestly preceding IBD but IBD not associated with an increased subsequent risk of anxiety.
In reciprocal analyses, 127,205 patients with IBS and matched controls were evaluated. During follow-up, 6.6% of the patients with IBS developed anxiety compared with 3.0% of controls. Among 89,509 patients with IBD, the incidence of anxiety was similar between exposed patients and controls, at 2.6% and 2.7%, respectively.
The investigators acknowledged several limitations. The retrospective observational design limited causal inference despite clear temporal sequencing. Because diagnoses were identified using administrative codes, misclassification was possible, and the investigators couldn't assess disease severity or changes in disease activity. Residual confounding from unmeasured factors, including socioeconomic status, diet, stress, and medication adherence may have persisted regardless of propensity score matching. Additionally, extensive exclusion criteria may have limited the generalizability of the findings to broader clinical populations.
“Comparison across disorders indicates that the associations in both temporal directions between anxiety and IBS are substantially stronger than those between anxiety and IBD,” noted lead study author Zachary Li, a medical student at the Drexel University College of Medicine, and colleagues.
Full disclosures can be found in the study.
Source: Cureus
