Background: Adherence plays an important role in the therapeutic effectiveness of medical therapy in inflammatory bowel disease (IBD). We assessed whether trust-in-physician and Black race were predictors of adherence.
Methods: We performed a cross-sectional study of Black (n = 120) and White (n = 115) IBD patients recruited from an outpatient IBD clinic. Self-reported adherence to taking medication and keeping appointments, trust-in-physician, and health-related quality of life were measured using the validated instruments, the modified Hill-Bone Compliance Scale (HBCS), the Trust-in-Physician Scale (TIPS), and the Short IBD Questionnaire (SIBDQ), respectively.
Results: Overall adherence was 65%. Higher adherence correlated with greater trust-in-physician (r = -0.30; P < 0.0001), increasing age (r = -0.19; P = 0.01), and worsening health-related quality of life (r = -0.18; P = 0.01). Adherence was also higher among White IBD patients compared to Blacks (HBSC: 15.6 versus 14.0, P < 0.0001). Trust-in-physician, race, and age remained predictors of adherence to medical management after adjustment for employment, income, health insurance, marital and socioeconomic status, and immunomodulator therapy. The adjusted odds ratio for adherence in Blacks compared to Whites was 0.29 (95% confidence interval: 0.13-0.64). Every half standard deviation increase in trust-in-physician and every incremental decade in age were associated with 36% and 47% higher likelihood of adherence, respectively.
Conclusions: Trust-in-physician is a potentially modifiable predictor of adherence to IBD medical therapy. Black IBD patients exhibited lower adherence compared to their White counterparts. Understanding the mechanisms of these racial differences may lead to better optimization of therapeutic effectiveness.