Impact of Dementia on Patients Admitted With Complicated Diverticular Disease: A U.S. Nationwide Analysis

Background Emerging research has suggested a link between diverticular disease and dementia, potentially mediated by alterations in the gut microbiome and chronic systemic inflammation. This study aimed to evaluate in-hospital outcomes in patients admitted with complicated diverticular disease (CDD) and pre-existing dementia. Methods We used the 2021 National Inpatient Sample (NIS), which reflects 97% of the U.S. population. Patients admitted with CDD, defined as diverticulitis, abscess, perforation, or bleeding, were identified and stratified by the presence or absence of a prior dementia diagnosis. In-hospital mortality was compared between groups. Subgroup analysis evaluated the impact of specific complications (perforation/abscess vs. diverticulitis/bleeding) on mortality among patients with dementia. Multivariable logistic regression was used to adjust for potential confounders. Results Of 221,460 patients admitted with CDD, 9,160 (4.1%) had a comorbid dementia diagnosis. Patients with dementia were older (mean age 82.5 years), predominantly female (64.9%), and more likely to have multiple comorbidities. Overall, in-hospital mortality was higher in the dementia group (unadjusted OR 3.41; 95% CI: 2.38-4.90; p < 0.01), though this was not statistically significant after adjustment (aOR 1.45; 95% CI: 0.97-2.16; p = 0.07). Subgroup analysis revealed that dementia was significantly associated with increased mortality among patients with perforation or abscess (aOR 2.07; 95% CI: 1.07-4.04; p = 0.03), but not in those with diverticulitis or bleeding alone. Conclusion Pre-existing dementia was associated with higher unadjusted mortality, but it was not statistically significant after adjustment, except in patients with CDD who presented with perforation or abscess.