Patients With Inflammatory Bowel Diseases Are at Higher Risk for Meningitis

The epidemiology of meningitis is unknown in inflammatory bowel disease (IBD) patients.

We aimed to determine the incidence of and risk factors for meningitis in IBD patients.

We conducted a retrospective cohort and nested case-control study in the Quintiles IMS Legacy PharMetrics Adjudicated Claims Database from January 2001 to June 2016. We matched IBD patients to those without IBD on age, sex, enrollment, and region. Meningitis was defined as one code for meningitis associated with an emergency department visit or hospitalization. Meningitis risk was calculated with incidence rate ratios. In a nested case-control study of IBD patients, predictors for meningitis were determined with multivariable conditional logistic regression models.

We identified 50,029 patients with Crohn's disease (CD) and 59,830 patients with ulcerative colitis (UC) matched to 296,801 non-IBD comparators. There were 85 CD patients, 77 UC patients, and 235 comparators with meningitis. CD patients had 2.17 times the rate of meningitis and UC patients had 1.63 times the rate of meningitis as non-IBD comparators. After adjusting for relevant covariates among those with IBD, treatment with mesalamine was associated with a significantly lower odds of a meningitis claim (odds ratio: 0.40, 95% confidence interval: 0.26-0.62). Having at least one comorbidity was associated with a significantly higher odds of a meningitis claim (odds ratio: 2.21, 95% confidence interval: 1.76-2.77).

Although the overall rate of meningitis is low, IBD patients are at an increased risk compared with non-IBD comparators. Comorbidities are a risk factor for meningitis in IBD patients. Pneumococcal and meningococcal vaccinations should be discussed.