Home Current Issue Previous Issues Published Ahead-of-Print Collections Blog For Authors Journal Info
Skip Navigation LinksHome > October 2013 - Volume 51 - Issue 10 > Multiple Medication Adherence and its Effect on Clinical Out...
Medical Care:
doi: 10.1097/MLR.0b013e31829fa8ed
Original Articles

Multiple Medication Adherence and its Effect on Clinical Outcomes Among Patients With Comorbid Type 2 Diabetes and Hypertension

An, JaeJin PhD*,†; Nichol, Michael B. PhD

Supplemental Author Material
Collapse Box

Abstract

Objective:

To investigate multiple medication adherence (MMA) and its impact on microvascular and macrovascular complications using instrumental variables (IVs).

Research Design:

A retrospective observational study was conducted using administrative claims and electronic medical records from a large physician group in Southern California (N=2334).

Subjects:

We identified individuals between January 2006 and June 2009 newly starting oral diabetes (DM) or hypertension (HTN) medications with preexisting comorbid HTN or DM prescription history.

Measures:

MMA was defined as a proportion of days covered where both DM and HTN medications were simultaneously available over a 33-month follow-up period. Microvascular or macrovascular complications included myocardial infarction, stroke, renal failure, and diabetic retinopathy. Multivariable logistic regressions and an IV estimation using physician-related variables were implemented.

Results:

MMA was supoptimal as the mean (SD) proportion of days covered was 0.53 (0.32). Patients were more adherent to medications for a preexisting condition in comparison with those for the newer disease. Older age, number of index medications [OR (95% CI)=1.36 (1.22–1.52)], receiving care from a physician who prescribed statin more frequently [OR (95% CI)=2.63 (1.67–4.14)], and receiving care from the same physician for both DM and HTN [OR (95% CI)=1.57 (1.08–2.27)] were significant factors of being adherent. Using physician-related IVs, MMA reduced microvascular and macrovascular complications. The increase in MMA from 50% to 80% reduced the average predicted probability of microvascular or macrovascular complication rate by 29.5%.

Conclusions:

Adherence to medications for DM and HTN were differed and higher MMA reduced microvascular or macrovascular complications when controlling for endogeneity bias.

Copyright © 2013 by Lippincott Williams & Wilkins

Login

Article Tools

Share

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.