Impact of interventions on medication adherence and blood pressure control in patients with essential hypertension: a systematic review by the ISPOR medication adherence and persistence special interest group.
OBJECTIVE
To systematically review the evidence on the impact of interventions to improve medication adherence in adults prescribed antihypertensive medications.


METHODS
An electronic search was undertaken of articles published between 1979 and 2009, without language restriction, that focused on interventions to improve antihypertensive medication adherence among patients (≥18 years) with essential hypertension. Studies must have measured adherence as an outcome of the intervention. We followed standard guidelines for the conduct and reporting of the review and conducted a narrative synthesis of reported data.


RESULTS
Ninety-seven articles were identified for inclusion; 35 (35 of 97, 36.1%) examined interventions to directly improve medication adherence, and the majority (58 of 97, 59.8%) were randomized controlled trials. Thirty-four (34 of 97, 35.1%) studies reported a statistically significant improvement in medication adherence.


CONCLUSIONS
Interventions aimed at improving patients' knowledge of medications possess the greatest potential clinical value in improving adherence with antihypertensive therapy. However, we identified several limitations of these studies, and advise future researchers to focus on using validated adherence measures, well-designed randomized controlled trials with relevant adherence and clinical outcomes, and guidelines on the appropriate design and analysis of adherence research.
Faculty of Science, Department of Computer Science, The University of Western Ontario, London, Ontario, Canada. femida.gwadry-sridhar@lhsc.on.ca
Femida H
FH
Gwadry-Sridhar
Elizabeth
E
Manias
Lincy
L
Lal
Maribel
M
Salas
Dyfrig A
DA
Hughes
Alexandria
A
Ratzki-Leewing
Maja
M
Grubisic
D000959:Antihypertensive Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D001794:Blood Pressure; D000075222:Essential Hypertension; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D055118:Medication Adherence; D010353:Patient Education as Topic / Q000379:methods; D017010:Reminder Systems
D000959:Antihypertensive Agents
hypertension; intervention; medication adherence; uncontrolled blood pressure