Adherence with topical glaucoma medication monitored electronically the Travatan Dosing Aid study.
OBJECTIVE
To assess patient adherence and behaviors with topical once-daily therapy for glaucoma.


METHODS
Prospective, observational cohort study.


METHODS
One hundred ninety-six patients with glaucoma who were being treated with a prostaglandin analog in 1 or both eyes at the Scheie or Wilmer Eye Institutes between August 2006 and June 2007.


METHODS
Detailed medical history was obtained from each patient. All subjects used the Travatan Dosing Aid (DA; Alcon, Fort Worth, TX) to administer travoprost as prescribed. Devices were collected at 3 months and the data of drop usage was downloaded using software provided with the dosing aid. Data were analyzed for the 8-week period starting 2 weeks after the enrollment visit and ending 2 weeks before the 3-month visit.


METHODS
Assessment of adherence and patterns of drop usage as indicated by the DA.


RESULTS
A total of 282 subjects consented to be in the study and 86 (30%) withdrew before study completion or had device errors, leaving 196 subjects (70%) with evaluable data at 3 months. The overall mean (+/-standard deviation) adherence rate was 0.71 (+/-0.24), ranging from 0.02 to 0.97. One hundred nine of these patients (55.6%) took greater than 75% of the expected doses. Those with adherence of less than 50% of expected doses showed substantially increased dose taking immediately after the office visit and just before the return visit at 3 months (P = 0.03). The mean adherence rate estimates of the physician and patient self-report were 0.77 and 0.95, respectively. The agreement between the physician assessment and DA-recorded adherence rate showed poor correlation for individual cases (intraclass correlation coefficient, 0.09; 95% confidence interval, 0.00-0.19).


CONCLUSIONS
Nearly 45% of patients using an electronic monitoring device who knew they were being monitored and were provided free medication used their drops less than 75% of the time. Patients reported far higher medication use than their actual behavior. The ability of the physician to identify which persons are poorly adherent from their self-report or from other subjective clues is poor.


BACKGROUND
Proprietary or commercial disclosure may be found after the references.
Okeke
Constance O
CO
Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA. constance.okeke@uphs.upenn.edu
Quigley
Harry A
HA
Jampel
Henry D
HD
Ying
Gui-shuang
GS
Plyler
Ryan J
RJ
Jiang
Yuzhen
Y
Friedman
David S
DS
D000287:Administration, Topical; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000008:administration & dosage*; D001294:Attitude to Health; D003008:Cloprostenol / Q000008:administration & dosage / Q000031:analogs & derivatives*; D015331:Cohort Studies; D016903:Drug Monitoring / Q000295:instrumentation; D005260:Female; D005500:Follow-Up Studies; D015812:Glaucoma, Angle-Closure / Q000188:drug therapy*; D005902:Glaucoma, Open-Angle / Q000188:drug therapy*; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D009798:Ocular Hypertension / Q000188:drug therapy; D009883:Ophthalmic Solutions / Q000008:administration & dosage; D010349:Patient Compliance / Q000706:statistics & numerical data*; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D000069557:Travoprost
D000959:Antihypertensive Agents; D009883:Ophthalmic Solutions; D003008:Cloprostenol; D000069557:Travoprost