BP Telemonitoring
Corey Diamond, PharmD
The need for increasing the reliability and effectiveness of home blood pressure monitoring (HBPM) has stimulated the development of more advanced blood pressure monitoring strategies, particularly in the sphere of team-based care and telehealth. Long-term follow-up data from the Hyperlink trial, published recently in Hypertension, may give insight into future avenues of patient blood pressure management strategies.
The Hyperlink trial randomized 450 patients—across 16 different clinics in the same U.S. health system—to receive clinical pharmacist-guided telemonitoring or conventional hypertension treatment (i.e., usual care from their primary care physician only) with the goal of reducing cardiovascular (CV) events.
Patients in the treatment arm received home blood pressure monitors to use in combination with hypertension case management from a medication
therapy management pharmacist over the phone for 6 months. Additionally, the blood pressure monitors transmitted all of the patient’s blood pressure data to a central server for the clinical pharmacist to interpret. The most recent analysis of Hyperlink’s data found an almost 50% relative reduction in CV events in the pharmacist intervention arm.
Pharmacist impact
Current clinical guidelines, such as the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults, have strongly recommended (Class I recommendation) that all patients with high blood pressure use HBPM for some time now, especially in conjunction with team-based care strategies.
However, an analysis of the reliability of simple self-reported home blood pressure measurements published in the American Journal of Hypertension by Mengden and colleagues, revealed that patient-reported values are extremely variable and unpredictable.
The Hyperlink trial isn’t the first to look at CV outcomes after implementation of pharmacist supervision. A meta-analysis published in the Journal of the American Heart Association in 2014 analyzed 39 randomized controlled trials that included pharmacist interventions on blood pressure management. The findings demonstrated that pharmacists’ interventions can reduce systolic and diastolic blood pressure by an average of 7.6 mm Hg and 3.9 mm Hg, respectively, compared with conventional management strategies.
Long-term relevance
While the inclusion of a pharmacist in managing patients’ blood pressure is effective, how does the Hyperlink trial inform practice beyond what we already know? On the surface, the intervention of the study may not be wholly unique, but its design is of particular relevance for long-term follow-up data.
Currently there is a dearth of long-term, clinically relevant outcomes with most team-based telehealth blood pressure studies—the majority do not follow patients beyond 1 to 2 years. The initial follow-up data from the Hyperlink trial was published in JAMA in 2013 and showed a significantly higher proportion of patients with controlled blood pressure—71.8% versus 57.1% after 18 months—in the telemonitoring intervention arm compared with the usual care arm.
Additionally, a follow-up analysis of Hyperlink’s data, published in JAMA in 2018, suggested that the blood pressure reduction observed from the intervention may last for up to 2 years. While these results were encouraging, they weren’t of particular clinical relevance.
Conversely, the most recent and notable analysis of Hyperlink’s data, published in the American Journal of Hypertension in August, looked at a CV composite outcome of the event rate of heart attack, stroke, heart failure, and CV death 5 years after the intervention.
The results showed that pharmacist telemonitoring interventions reduced the incidence of CV events by approximately 50%. Although these results were not statistically significant, Hyperlink only had 80% power to detect a difference at the 1-year follow-up mark. The fact that the study was able to find a statistical difference at the 18-month mark in blood pressure outcomes, and a difference with such a large effect size, albeit statistically insignificant, at the 5-year mark in clinical outcomes is encouraging.
Using a predictive modeling simulation that incorporated blood pressure patterns from two different HBPM meta-analyses, the authors demonstrated that the difference in blood pressure observed at the 5-year follow-up point was far greater than predicted.
If the reduction in events is not a chance finding, then the intervention may be effective as a long-term treatment strategy and could have implications for general practice, with cost savings of roughly $1900 per patient over 5 years. The results of Hyperlink’s 5-year follow-up data present a promising prospect for future studies that are properly powered to confirm. These results may even lead to new pharmacy-driven telehealth hypertension treatment initiatives for patients.