JMIR Publications

ABSTRACT

Background:

The use of mobile health (mHealth) interventions, including smartphone applications (apps), for cardiovascular disease (CVD) prevention has demonstrated mixed results for overweight/obesity, hypercholesterolemia, diabetes, and hypertension management. A major factor attributing to the variation in mHealth study results may be mHealth user engagement.

Objective:

The purpose of this systematic review was to determine if user engagement with smartphone apps for CVD prevention and management is associated with improved CVD health behavior change and risk factor outcomes.

Methods:

We conducted a comprehensive search of PubMed, CINAHL, and Embase from 2007-2020. Studies were eligible if they assessed whether user engagement with a smartphone app, used by an individual to manage his/her CVD risk factors, was associated with the CVD health behavior change or risk factor outcomes. For eligible studies, data were extracted on study and sample characteristics, intervention description, app user engagement measures, and the relationship between app user engagement and the CVD health behavior change/risk factor outcome. App user engagement was operationalized as general usage (e.g. number of log-ins or usage days per week) and/or self-monitoring within the app (e.g. total number of entries made in the app). The quality of the studies was assessed.

Results:

Of the 24 studies included in this review, 17 used a randomized controlled trial design, four a retrospective analysis, and three a single-arm pre and post-test design. Sample sizes ranged from 55 to 324,649 adults with 19 of the studies recruiting participants from a community setting. Most of the studies assessed weight loss interventions with six addressing additional CVD risk factors including diabetes, sleep, stress, and alcohol consumption. Most of the studies that assessed the relationship between user engagement and reduction in weight [9/13 (69%)], body mass index (BMI) [3/4 (75%)], body fat percentage [2/3 (67%)], waist circumference [2/3 (67%)], and hemoglobin A1c [3/5 (60%)] found statistically significant results; indicating greater app user engagement was associated with better outcomes. Three of four studies (75%) found a statistically significant relationship between higher user engagement and increase in objectively measured physical activity. The studies assessing the relationship between user engagement and dietary and/or diabetes self-care behaviors, blood pressure, and lipid panel components did not find statistically significant results.

Conclusions:

Increased app user engagement for CVD prevention and management may be associated with improved weight/BMI; however, only a few studies assessed the other outcomes, limiting the evidence beyond this. Additional studies are needed to assess user engagement with smartphone apps targeting other important CVD risk factors, including: healthy dietary behaviors, hypercholesterolemia, diabetes, and hypertension. Further research is needed to assess mHealth user engagement in both inpatient and outpatient settings, to determine the effect of integrating mHealth interventions into the existing clinical workflow and on CVD outcomes.