Abstract
Abstract: :
Purpose:To determine the predictors of treatment and predictors of treatment persistence and adherence for glaucoma and suspect glaucoma patients in a nationally representative sample of diagnosed persons. Methods:Retrospective cohort study using health insurance claims of 35,754 new glaucoma suspects and 5,265 new open angle glaucoma patients. Linked pharmacy and patient care information were used to assess factors possibly predictive of treatment (medicines, laser or surgery) and to calculate duration of continuous treatment with initially prescribed topical medication (persistence) as well as the prevalence of medication use (adherence). A logistic regression model adjusting for diagnostic group (suspect vs. diagnosed), age group, sex, region of the country, date of initial diagnosis divided into two periods (1995 – 1998 and 1999 – 2001), and length of follow–up was performed to assess the predictors of treatment and persistence/adherence in this cohort. Results:Treatment was prescribed in 42% of those with glaucoma and 8% of suspects. Women were less likely to undergo treatment than men (OR = 0.76, 95% CI 0.71, 0.81). Factors other than gender that were associated with greater likelihood of treatment were glaucoma diagnosis, older age, region, and longer follow–up. Half of those filling an initial prescription discontinued therapy within 6 months and only 37% had recently refilled their initial medication 3 years after dispensing. Prostaglandins were associated with better persistence and adherence among glaucoma patients (hazard ratios for discontinuation compared with beta–blockers = 0.40 (95% CI, 0.35–0.44)). Glaucoma patients were more likely to adhere than suspects (OR = 1.21; 95% CI, 1.12–1.31). Conclusions:Many persons with glaucoma or suspect glaucoma discontinue care. Persistence and adherence are substantially better with prostaglandins than with other drugs. Patients diagnosed with glaucoma are more likely to adhere to treatment than glaucoma suspects. Furthermore, women are 24% less likely to be treated than men, and younger individuals are less likely to be treated than older ones. Understanding the reasons for poor adherence and persistence as well as the causes for variation in who is treated will help in developing better management strategies for individuals with glaucoma and suspect glaucoma.
Keywords: clinical (human) or epidemiologic studies: health care delivery/economics/manpower • clinical (human) or epidemiologic studies: natural history • pharmacology