Among patients with uncontrolled hypertension, an intervention consisting of home BP telemonitoring and pharmacist management may aid in reducing BP for up to 24 months, but other maintenance strategies may be required to sustain these effects over a longer time period, according to a study published in JAMA Network Open.
“Studies conducted in a variety of settings have found that telemedicine interventions can significantly improve hypertension management when combined with nurse-led or pharmacist-led care,” Karen L. Margolis, MD, MPH, senior medical director at HealthPartners Institute and professor of medicine at the University of Minnesota Medical School, Minneapolis, and colleagues wrote. “The results were previously reported of a cluster-randomized clinical trial evaluating home BP telemonitoring with pharmacist management compared with usual care, with significant reductions in BP favoring the intervention group over 18 months. However, a barrier to implementing similar interventions in clinical practice is the scarcity of data on long-term treatment results beyond 12 months.”
Effectiveness of telemedicine
Researchers investigated the effectiveness of telemedicine on long-term hypertension outcomes by conducting a follow-up analysis of a cluster-randomized clinical trial, which included 16 primary care clinics and 450 patients with uncontrolled hypertension (BP 140 mm Hg systolic/90 mm Hg diastolic) at HealthPartners Medical Group, from March 2009 to November 2015. Researchers randomly assigned 228 patients to the intervention group, in which they were given a home BP monitor and engaged in visits and phone calls with a pharmacist for management (mean age, 62 years; 55% men; mean baseline BP, 148.2 mm Hg systolic/84.5 mm Hg diastolic). The other 222 were randomly assigned to usual care, in which patients continued with their primary care physicians as they normally would (mean age, 60 years; 56% men; mean baseline BP, 147.7 mm Hg systolic/84.9 mm Hg diastolic).
The primary outcome was change in systolic BP from baseline to 54 months as determined by the mean of three measurements recorded at each research clinic visit. BP data obtained from the electronic health record at clinic visits — not associated with the research clinic visits — were also considered. Other outcomes included changes in diastolic BP from baseline to 54 months and the number of antihypertensive medication classes that were recorded from the medication inventory at each visit.
BP was also measured at 6, 12 and 18 months.
Researchers found that, for the intervention group, mean systolic BP at 6-, 12-, 18- and 54-month follow-up was 126.7 mm Hg, 125.7 mm Hg, 126.9 mm Hg and 130.6 mm Hg, respectively. For usual care, mean systolic BP at 6, 12, 18 and 54 months was 136.9 mm Hg, 134.8 mm Hg, 133 mm Hg and 132.6 mm Hg, respectively.
From baseline to 54 months, the differential reduction by study group in systolic BP was –2.5 mm Hg (95% CI, –6.3 to 1.2) and –1 mm Hg (95% CI, –3.2 to 1.2) for diastolic BP.
Increases in the number of antihypertensive medication classes from baseline to 54 months were 0.63 (95% CI, 0.46-0.79) in the intervention group and 0.64 (95% CI, 0.47-0.8) in usual care.
Systolic and diastolic BP readings from routine clinical measurements documented in the electronic health record suggested a sustained significant difference favoring the intervention group through 24 months, Margolis and colleagues wrote.
There was no differential long-term increase in the use of home BP monitoring with 59.6% of the intervention group using home BP monitoring — compared with 50% of the usual care group — at 54 months.
“Such BP reductions of this magnitude and duration have the potential to result in clinically important effects on cardiovascular events, even if BP was not different at 54 months,” the researchers wrote. “Nevertheless, long-term maintenance of BP control is likely to require continued monitoring and resumption of the intervention if BP increases. More work is needed to determine the content, intensity and duration of reinforcement that are needed for maintaining intervention benefits over a longer period.” – by Melissa J. Webb
Margolis reports receiving grants from the NIH/NHLBI and from the Patient-Centered Outcomes Research Institute. Please see the study for all other authors’ relevant financial disclosures.