Study Highlights

• The investigators identified adult patients with IBD who were new users of biologic agents (TNF-alpha antagonists, ustekinumab, vedolizumab) from 5 academic institutions in California between 2010 and 2017.
• Using 1:4 propensity score matching and survival analysis, they compared risks for all-cause hospitalization, IBD-related surgery, and serious infections in 240 Hispanic vs 960 non-Hispanic patients.
• Hispanic patients were 53% male, 73% were TNF-alpha antagonist-treated, 20% had prior biologic exposure, and 45% had ulcerative colitis.
• Non-Hispanic patients were 51% male, 67% were TNF-alpha antagonist-treated, 27% had prior biologic exposure, and 44% had ulcerative colitis.
• Before propensity score matching, Hispanic patients were significantly younger, more likely to be overweight and obese, more likely to have increased C-reactive protein and low albumin levels, more likely to be receiving a concomitant immunomodulator and opiates when biologics were started, and more likely to be hospitalized at baseline 1 year before biologic initiation.
• After propensity score matching, Hispanics were younger (37±15 vs 40±16 years; P=.02) and had a higher comorbidity burden (Elixhauser index, >0; 37% vs 26%; P<.01), but patterns of medication use, inflammation burden, and hospitalizations did not differ.
• Within 1 year of starting a biologic, Hispanics had higher rates of hospitalizations (31% vs 23%; adjusted hazard ratio [aHR], 1.32; 95% CI, 1.01-1.74) and IBD-related surgery (7.1% vs 4.6%; aHR, 2.00; 95% CI, 1.07-3.72), and a trend toward higher risk for serious infections (8.8% vs 4.9%; aHR, 1.74; 95% CI, 0.99-3.05).
• Results for hospitalization and IBD surgery were similar in the full cohort in patients with Crohn's disease and ulcerative colitis.
• Hispanics treated with TNF-alpha antagonists had higher hospitalization risks than non-Hispanics (32% vs 21%; P<.01), but those treated with vedolizumab (30% vs 27%; P=.88) and ustekinumab (29% vs 28%; P=1.00) did not.
• In Cox proportional hazard analysis adjusting for demographic-, disease-, and treatment-related factors and health care use, Hispanics were 33% more likely to be hospitalized than non-Hispanics (aHR, 1.33; 95% CI, 1.05-1.70) and 71% more likely to undergo IBD-related surgery (aHR, 1.71; 95% CI, 1.01-1.92).
• Risks for hospitalization were increased with Hispanic ethnicity, higher comorbidity burden (aHR, 1.45; 95% CI, 1.23-1.70), prior hospitalization at baseline (aHR, 1.40; 95% CI, 1.18-1.65), and concomitant use of opiates (aHR, 3.37; 95% CI, 2.89-3.92) and corticosteroids (aHR, 1.43; 95% CI, 1.23-1.67).

Risks for IBD-related surgery were increased with Hispanic ethnicity, increased baseline C-reactive protein (aHR, 2.83; 95% CI, 1.66-4.85), prior IBD-related surgery (aHR, 1.92; 95% CI, 1.01-3.64), prior biologic exposure (aHR, 1.77; 95% CI, 1.08-2.72), and concomitant opiate use (aHR, 3.45; 95% CI, 2.25-5.29). 

Table 1.

CI = confidence interval; HR = hazard ratio.

• The investigators concluded that in a multicenter cohort of biologic-treated patients with IBD, Hispanic patients had higher rates of hospitalization, surgery, and serious infections after propensity score matching accounting for differences in demographic, clinical, and treatment-related factors, including inflammatory burden and prior medication exposure.
• Combined with evidence from previous studies, these findings suggest that biologic agents may not be as effective or safe in Hispanic patients as they are in non-Hispanic Caucasians, with differences perhaps driven by biological or socioeconomic factors.
• Lower effectiveness of biologics may be driven by differences in disease duration resulting from potential delays in biologic initiation in Hispanics, endoscopic severity, and other unmeasured factors.
• The findings suggest disproportionately higher rates of unplanned health care use compared with non-Hispanic patients, as well as ethnicity driving potential differences in biologic agent effectiveness.
• Genetic determinants also may influence the effectiveness of specific biologic agents, but this has been incompletely studied in Hispanic patients.
• National Health Interview Survey data showed that Hispanic patients with IBD had a higher prevalence of negative social determinants of health, particularly food insecurity (27%) and lack of adequate social support (83%) compared with non-Hispanic Caucasians.
• Previous research has also shown limited access of Hispanics to appropriate specialist care and lack of insurance coverage.
• Risk for hospitalization and surgery was higher in Hispanic patients treated with TNF-alpha antagonists but not in ustekinumab-treated patients, but this should be interpreted with caution because of the small number of Hispanic patients treated with non-TNF biologics.
• The investigators recommend additional research to identify biological, social, and environmental drivers of these disparities in health care use and treatment outcomes.
• Study limitations include lack of data on primary vs secondary discharge diagnoses preventing determination of the primary reason for hospitalization, reliance on prescriptions written rather than filled, and selection bias as only patients treated with biologics were included, not those who may have needed a biologic treatment but were unable to receive it.