Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2016 Nov 22;6(11):e011650.
doi: 10.1136/bmjopen-2016-011650.

Comparison of therapy persistence for fixed versus free combination antihypertensives: a retrospective cohort study

Thomas Grimmsmann  1   2 , Wolfgang Himmel  3
Affiliations

Comparison of therapy persistence for fixed versus free combination antihypertensives: a retrospective cohort study

Thomas Grimmsmann et al. BMJ Open. .

Abstract

Objectives: The aim of the study was to compare therapy persistence among patients who started with one of three drug regimens: a monotherapy, or combination therapy either as a fixed combination (ie, 'single pill') or as a free combination (ie, two separate antihypertensive agents).

Design: In a secondary data analysis, we used descriptive statistics and multivariate logistic regression to measure the effect of the three therapy regimens on therapy persistence over 4 years.

Setting: Prescription data from a large German statutory health insurance provider.

Participants: All patients who started with a new antihypertensive therapy in 2007 or 2008 (n=8032) were included and followed for 4 years.

Primary outcome measure: Therapy persistence, defined as receiving a refill prescription no later than within 180 days.

Results: The persistence rates after 4 years were nearly identical among patients who started with a monotherapy (40.3%) or a fixed combination of two drugs (39.8%). However, significantly more patients who started with free-drug combinations remained therapy persistent (56.4%), resulting in an OR of 2.00 (95% CI 1.6 to 2.5; p<0.0001) for free combinations versus fixed combinations. This trend was observed in all age groups and for men and women. At the end of the study period, the number of different antihypertensive agents was still similar between patients who started with a fixed combination (2.41) and patients who started with a free combination (2.28).

Conclusions: While single-pill combinations make it easier to take different drugs at once, the risk is high that these several substances are stopped at once. Therapy persistence was significantly better for patients who started with a free-drug combination without taking much fewer different antihypertensive drugs as those with a fixed combination.

Keywords: Drug adherence; Drug combinations; Drug utilization review; Patient compliance; Primary health care.

PubMed Disclaimer

Conflict of interest statement

Conflicts of Interest: None declared.

Figures

Figure 1
Figure 1
Five repeat prescription scenarios.
Figure 2
Figure 2
Number of different drugs.
See this image and copyright information in PMC

References

    1. Mancia G, Fagard R, Narkiewicz K et al. . 2013 ESH/ESC Guidelines for the management of arterial hypertension: the task force for the management of arterial hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC). Eur Heart J 2013;31:1281–357. - PubMed
    1. Claxton AJ, Cramer J, Pierce C. A systematic review of the associations between dose regimens and medication compliance. Clin Ther 2001;23:1296–310. 10.1016/S0149-2918(01)80109-0 - DOI - PubMed
    1. Gupta AK, Arshad S, Poulter NR. Compliance, safety, and effectiveness of fixed-dose combinations of antihypertensive agents: a meta-analysis. Hypertension 2010;55:399–407. 10.1161/HYPERTENSIONAHA.109.139816 - DOI - PubMed
    1. Dezii CM. A retrospective study of persistence with single-pill combination therapy vs. concurrent two-pill therapy in patients with hypertension. Manag Care 2001;10(2 Suppl):6–10. - PubMed
    1. Jackson K, Brixner D, Oderda G et al. . Compliance and persistence of fixed dose versus free dose combination therapy with valsartan and HCTZ for patients with hypertension. Value Health 2006;9:A363 10.1016/S1098-3015(10)63700-X - DOI

LinkOut - more resources