Abstract
Purpose: :
Non-adherence is a critical factor associated with failure of topical therapy in glaucoma. Electronic reminder systems for eye drop medications may allow improving adherence to intraocular-pressure lowering agents. This pilot study aimed to assess the functionality of a new visual and audible reminder system for latanoprost eye drops and its impact on adherence rates in patients with glaucoma or ocular hypertension.
Methods: :
Commercially available eye drops containing 0.005 % latanoprost (Xalatan®, Pfizer Pharma GmbH, Germany) were placed in modified dosing aids (Xal-Ease™, Pfizer Pharma GmbH) equipped with electronic adherence monitoring and reminder devices. After written informed consent and with approval of the ethics committee 9 patients with glaucoma or ocular hypertension applied latanoprost eye drops once-daily for 2 months. Patients received new medication on monthly return appointments. During the first month the devices were programmed to record adherence without emission of any reminder signal. During the second month the therapy was enforced by audible and visual signals emitted from the electronic devices in case of non-adherence at designated hours (9 pm). Electronic dosing information was analyzed for mean rates of adherence, coverage and dosing time intervals. End of coverage was defined as dosing intervals exceeding 27 hours. The effect of the reminder signals was assed by comparisons of means for the first month (without reminder signal) the second month (with reminder signal) and used non parametric tests: Mann-Whitney-U test or Wilcoxon signed rank test where applicable.
Results: :
One patient quit the study due to handling difficulties with the Xal-Ease™ device. The mean dose adherence rate of the remaining 8 patients with activated audible and visual reminder signals was 99.8 ±1.1 % and thus significantly higher than without reminder signals (mean 91.1 ±25.8 %, p=0.03). Accordingly, the mean dosing intervals were also reduced from 31.3 ±20.2 to 23.7 ±0.6 hours (p=0.04) with active reminder signals. Without reminder signals 3 out of 8 patients had a drug coverage rate below 90% (mean 85.7 ±25.9 %), whereas with activated reminder signal all patients had a coverage rate above 95% (mean 98.7 ±1.9 %, p=0.09).
Conclusions: :
Audible and visual reminder signals improved significantly adherence to topical latanoprost for glaucoma in this pilot study. Our data show that electronic reminder devices can be useful in glaucoma therapy even for medications with a once-daily dosing schedule. Still, the long-term effect of this reminder system on adherence remains to be studied in large cohorts.
Keywords: clinical (human) or epidemiologic studies: systems/equipment/techniques • clinical (human) or epidemiologic studies: health care delivery/economics/manpower • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials