Abstract
Purpose: :
Noncompliance with topical therapy in glaucoma may lead to visual loss. Glaucoma patients constitute the most important group using long term eyedrop therapy. Retrospective cohort studies suggest the rate of non–adherence in glaucoma patients to be of major importance. Monitoring individual adherence shall permit to improve the understanding of therapy failures and the reasons why certain patients fail and others not. Therefore individual adherence with Brimonidine therapy was studied in glaucoma patients.
Methods: :
Conventional eyedrops containing Brimonidine (Alphagan®, AllerganTM) were equipped with a microprocessor–controlled monitoring device capable to record date and time of each eyedrop application including ambient temperature. After written informed consent 20 glaucoma and ocular hypertensive patients used to eyedrop therapy were randomly assigned to Brimonidine therapy 3x or 2x daily for 4 weeks. IOP was measured at baseline and on days 7, 14, 21, 28. Furthermore ten of the patients were randomly assigned to keep the bottles refrigerated.
Results: :
According to the monitoring devices all patients were non–compliant with regards to total dose and coverage. Electronic records revealed a mean of 1.5 applications per day for patients assigned to Brimonidine 2x daily with a mean dose interval of 15.2 hours (range: 4–71 h). Patients with Brimonidine 3x daily showed a mean rate of 1.8 applications per day and a mean dose interval of 12.8 hours (range: 2–68 h). Recorded temperatures of the patients assigned to keep the bottles refrigerated were significantly lower compared to the other participants. One patient discontinued therapy prematurely. Adherence was not remarkably influenced by return appointments.
Conclusions: :
Individual adherence with conventional Brimonidine eyedrops was studied for the first time using a recently developed compliance monitoring device with a known detection sensitivity for eyedrop applications above 99% (ARVO 2005). The monitoring devices permitted to detect individual patient noncompliance with a mean of 20% missed doses in the Brimonidine 2x group and 40% missed doses in the Brimonidine 3x group and thereby underlining the importance and necessity for further investigations.
Keywords: clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials • pharmacology • clinical research methodology