Abstract
Background: Cardiovascular
disease (CVD) is the leading cause of death globally and in Canada.
Diabetes and hypertension are major risk factors for CVD events. Despite
the increasing availability of effective treatments, the majority of
diabetic and hypertensive patients do not have adequate blood pressure
and glycemic control. One of the major contributors is poor treatment
adherence.
Objective: This
study aims to evaluate the impact of treatment adherence for patients
with both diabetes and hypertension on acute severe CVD events and
intermediate clinical outcomes in Canadian primary care settings.
Methods: We
will conduct a population-based retrospective cohort study of patients
living with both diabetes and hypertension in Ontario, Canada, between
January 1, 2008, and March 31, 2018. The Social Cognitive Theory will be
used as a conceptual framework by which to frame the reciprocal
relationship between treatment adherence, personal factors, and
environmental determinants and how this interplay impacts CVD events and
clinical outcomes. Data will be derived from the Diabetes Action Canada
National Data Repository. A time-varying Cox proportional hazards model
will be used to estimate the impacts of treatment adherence on CVD
morbidity and mortality. Multivariable linear regression models and
hierarchical regression models will be used to estimate the associations
between treatment adherence of different medication categories and
intermediate clinical outcomes. Our primary outcome is the association
between treatment adherence and the risk of acute severe CVD events,
including CVD mortality. The secondary outcome is the association
between treatment adherence and intermediate clinical outcomes including
diastolic and systolic blood pressures, glycated hemoglobin,
low-density lipoprotein cholesterol, and total cholesterol. Owing to
data limitation, we use medication prescriptions as a proxy to estimate
treatment adherence. We assume that a patient adhered to medications if
she or he had any prescription record in the 4 preceding quarters and 1
quarter after each quarter of interest. Acute severe CVD events are
defined based on the World Health Organization’s Monitoring Trends and
Determinants in Cardiovascular Disease Project, including acute coronary
heart disease, stroke, and heart failure. As causes of death are not
available, the number of CVD deaths will be computed using the most
recent systolic blood pressure distributions and the population
attributable risks related to systolic blood pressure level.
Results: The
project was funded by Diabetes Action Canada (reference number: 503854)
and approved by the University of Toronto Research Ethics Board
(reference number: 36065). The project started in June 2018 and is
expected to be finished by September 2019.
| Original language | English |
|---|---|
| Article number | e13571 |
| Number of pages | 11 |
| Journal | JMIR Research Protocols |
| Volume | 8 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - 31 May 2019 |
Keywords
- Treatment adherence
- Cardiovascular disease
- Primary care
Access to Document
- Su_2019_JMIRProtocols_Treatmentadherence_CC
Copyright © 2019 Min Su, Victoria Haldane, Ross Upshur, Frank Sullivan, France Légaré, Michelle Greiver, Xiaolin Wei. Originally published in JMIR Research Protocols (http://www.researchprotocols.org). This is an open-access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in JMIR Research Protocols, is properly cited. The complete bibliographic information, a link to the original publication on http://www.researchprotocols.org, as well as this copyright and license information must be included.