Effects of a Dietitian-Led, Telehealth Lifestyle Intervention on Blood Pressure: Results of a Randomized, Controlled Trial

Abstract

Background Limited data exist on the benefits of lifestyle behavior change delivered using telehealth and web-based applications with varied support on blood pressure (BP). Methods and Results We conducted a 2-site randomized controlled trial at Geisinger (January 2019-March 2021) to compare the efficacy of 2 remotely delivered strategies using web-based applications in participants with 24-hour systolic BP 120-160 mm Hg and body mass index ≥25 kg/m2. Both arms received access to web-based applications and the same lifestyle guidance per American Heart Association guidelines. One arm received minimal nonclinical staff support, and the other arm received dietitian support with motivational interviewing during weekly calls. The primary outcome was 12-week change in 24-hour systolic BP. A total of 187 participants were randomly assigned, with 156 (83.4%) completing the trial. In both arms, 24-hour systolic BP was reduced at follow-up, but the difference in BP change was not significant (dietitian-led arm, -6.73 mm Hg [95% CI, -8.64 to -4.82]; minimal-support arm, -4.92 [95% CI, -7.01 to -2.77]; P comparing groups=0.2). The dietitian-support arm had greater 12-week improvements in the secondary outcomes sleep systolic BP (mean, -6.92 versus -1.45; P=0.004), sleep diastolic BP (-3.31 versus 0.73; P=0.001), and self-reported physical activity (866 versus -243 metabolic equivalent task minutes per week; P=0.01) and tended to have improvements in weight loss (-5.11 versus -3.89 kg; P=0.1) and Healthy Eating Index-2015 score (9.23 versus 6.43 units; P=0.09). Conclusions Both the dietitian- and minimal-support interventions reduced 24-hour systolic BP similarly, although the dietitian-led intervention led to greater improvements in several secondary cardiometabolic outcomes. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03700710.

Keywords: behavior change; blood pressure; diet; healthy lifestyle; mHealth; motivational interviewing; weight loss.

Figures

Figure 1. Study flow diagram.

ABPM indicates ambulatory blood pressure monitoring; BP, blood pressure; and SV, study visit.

Figure 2. Hourly SBP and DBP measured by 24‐hour ABPM.

Mean hourly SBP and DBP for each study group were calculated at baseline and 12 weeks and plotted using lowess smoothing. ABPM indicates ambulatory blood pressure monitoring; DBP, diastolic blood pressure; and SBP, systolic blood pressure.

Figure 3. American Heart Association blood pressure categories at baseline and 12 weeks.

Breakdown of American Heart Association blood pressure categories at baseline and 12 weeks among participants with complete 24‐hour ambulatory blood pressure monitoring data. At the end of 3 months, 41.0% of the dietitian‐support arm and 28.2% of the minimal‐support arm had awake blood pressure at P value comparing groups=0.09). DBP indicates diastolic blood pressure; and SBP, systolic blood pressure.

Figure 4. Satisfaction by study arm.

χ2 test, P=0.004. BP indicates blood pressure.