Appointment adherence and disparities in outcomes among patients with diabetes.

Background: Successful control of diabetes mellitus requires lifelong adherence to multiple self-management activities in close collaboration with health professionals. We examined the association of such control with appointment keeping behavior in a rural health system.

Methods: Among 4,253 predominantly lower socioeconomic status patients with diabetes, the association of metabolic control (most recent A1c <7% or >9% in two models of respectively 'good' and 'poor' control) with 'missed appointment rate' over a 3-year period was examined using multiple logistic regression.

Main Results: For each 10% increment in missed appointment rate, the odds of good control decreased 1.12x (p < 0.001) and the odds of poor control increased 1.24x (p < 0.001). The missed appointment rate was substantially higher among African-American patients (15.9% vs. 9.3% for white patients, p < 0.001). Controlling for the missed appointment rate and insurance status in multivariate analysis attenuated the racial association with good control, and the racial association with poor control was no longer significant. Older, white patients with health insurance tended to have significantly better metabolic control. There was no independent association of metabolic control with patient income, gender, or number of primary care visits.

Conclusion: Adherence to appointments, independent of visit frequency, was a strong predictor of diabetes metabolic control. We hypothesize that missed appointment behavior may serve as an indicator for other diabetes adherence behaviors and associated barriers that serve to undermine successful diabetes self-management.