Adherence to Oral Hypoglycemic Agents in 26 782 Chinese Patients: A Cohort Study

Abstract

This study evaluated the factors associated with adherence to oral hypoglycemic agents (OHAs) among Chinese patients. A validated clinical database was used to include all adult patients who were prescribed an OHA in any of the government clinics in a large territory of Hong Kong from January 1, 2004, to June 30, 2007 and made 1 or more subsequent visits for OHA refill. Patients with medication possession ratio (MPR) 0.8 or greater were regarded as medication adherent. One binary logistic regression analysis was performed to test the association between age, gender, visit types (new vs follow-up visits), and MPR while controlling for socioeconomic status, service settings, number of comorbidities, and the medication class prescribed (sulphonylurea vs biguanide vs combination of both). Among 26,782 patients, 89.6% were adherent. Older patients (aged 50-59 years; adjusted odds ratio [AOR] 1.19; 95% confidence interval [CI], 1.06-1.34, P = .004; 60-69 years; AOR 1.37; 95% CI, 1.21-1.55, P < .001; ≥70 years; AOR 1.52; 95% CI, 1.34-1.72, P < .001) and follow-up visitors (AOR 3.89; 95% CI, 3.55-4.27, P < .001) were more likely to be medication adherent. Male subjects were less likely to adhere (AOR 0.84; 95% CI, 0.77-0.91, P < .001). Newer medication adherence-enhancing strategies should be implemented, especially among younger patients, male subjects, and new clinic attendees to secure optimal adherence.