Improving Medication Adherence through Graphically Enhanced Interventions in Coronary Heart Disease (IMAGE-CHD): a randomized controlled trial.
BACKGROUND
Up to 50 % of patients do not take medications as prescribed. Interventions to improve adherence are needed, with an understanding of which patients benefit most.


OBJECTIVE
To test the effect of two low-literacy interventions on medication adherence.


METHODS
Randomized controlled trial, 2 × 2 factorial design.


METHODS
Adults with coronary heart disease in an inner-city primary care clinic.


METHODS
For 1 year, patients received usual care, refill reminder postcards, illustrated daily medication schedules, or both interventions.


METHODS
The primary outcome was cardiovascular medication refill adherence, assessed by the cumulative medication gap (CMG). Patients with CMG<0.20 were considered adherent. We assessed the effect of the interventions overall and, post-hoc, in subgroups of interest.


RESULTS
Most of the 435 participants were elderly (mean age=63.7 years), African-American (91 %), and read below the 9th-grade level (78 %). Among the 420 subjects (97 %) for whom CMG could be calculated, 138 (32.9 %) had CMG<0.20 during follow-up and were considered adherent. Overall, adherence did not differ significantly across treatments: 31.2 % in usual care, 28.3 % with mailed refill reminders, 34.2 % with illustrated medication schedules, and 36.9 % with both interventions. In post-hoc analyses, illustrated medication schedules led to significantly greater odds of adherence among patients who at baseline had more than eight medications (OR=2.2; 95 % CI, 1.21 to 4.04) or low self-efficacy for managing medications (OR=2.15; 95 % CI, 1.11 to 4.16); a trend was present among patients who reported non-adherence at baseline (OR=1.89; 95 % CI, 0.99 to 3.60).


CONCLUSIONS
The interventions did not improve adherence overall. Illustrated medication schedules may improve adherence among patients with low self-efficacy, polypharmacy, or baseline non-adherence, though this requires confirmation.
Section of Hospital Medicine, Division of General Internal Medicine and Public Health, Department of Medicine, Vanderbilt University, Nashville, TN 37232, USA. sunil.kripalani@vanderbilt.edu
Sunil
S
Kripalani
Brian
B
Schmotzer
Terry A
TA
Jacobson
D000328:Adult; D000368:Aged; D000553:Ambulatory Care / Q000379:methods; D000704:Analysis of Variance; D002317:Cardiovascular Agents / Q000008:administration & dosage*; D016009:Chi-Square Distribution; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000188:drug therapy*; D004348:Drug Labeling; D004522:Educational Status; D005260:Female; D006801:Humans; D008297:Male; D008488:Medical Illustration; D008875:Middle Aged; D016017:Odds Ratio; D010349:Patient Compliance / Q000706:statistics & numerical data; D010353:Patient Education as Topic / Q000379:methods*; D019338:Polypharmacy; D011203:Poverty; D011320:Primary Health Care / Q000379:methods; D058996:Quality Improvement; D017010:Reminder Systems / Q000706:statistics & numerical data*; D016037:Single-Blind Method; D014505:Urban Population; D016903:Drug Monitoring
D002317:Cardiovascular Agents