Home blood pressure telemonitoring with pharmacist management lowered blood pressure more than usual care for 18 months… but the benefits weren’t sustained long-term
A study recently published in JAMA has suggested that long-term maintenance strategies may be needed to sustain the positive effects of blood pressure interventions over several years.
Between 2009 and 2015, a cluster randomised clinical trial was conducted with 450 patients with uncontrolled hypertension at HealthPartners Medical Group, a multi-specialty practice in Minnesota.
The patients had a blood pressure of uncontrolled 140/90m Hg or higher (or 130/80mm Hg if diabetes or kidney disease were present) at the two most recently primary care encounters in the previous year.
Patients randomised to the telemonitoring intervention group received a home automated oscillometric BP monitor that stored and transmitted blood pressure data to the secure AMC Health website.
“Pharmacists met with patients in person for a one-hour intake visit during which they conducted a personalised medication review, taught them how to use the home BP telemonitoring system, and provided information about hypertension management,” the authors write.
“Patients were instructed to transmit at least six BP measurements weekly (three in the morning and three in the evening) and were given an individualised home BP goal (ie, <135/85 mm Hg or <125/75 mm Hg for patients with diabetes or kidney disease).
“During the first six months of the intervention, patients and pharmacists met every two weeks via telephone until BP control was sustained for six weeks, and then the frequency was reduced to monthly.
“During the second six months of the intervention period, telephone visits were reduced to every two months. After 12 months, patients returned the telemonitors, went back to their primary physicians’ care, and received no further pharmacist support unless they or their physicians sought it outside of the study.
“Telephone visits included review of home BP data, discussion of adherence to medication and lifestyle changes, and treatment issues that patients might be experiencing.
“Pharmacists were asked to adjust antihypertensive drug therapy if less than 75% of readings since the last visit met the BP goal. Regardless of BP control, the drug dosage could be lowered or the drug changed if patients experienced adverse effects. Pharmacists communicated with patients’ primary care teams through the EHR after each visit.”
During the study period, patients randomised to the usual care group worked with their primary care physicians as usual. For some, this could include referral to an MTM pharmacist for consultation (one or two visits without telephone follow-up or prolonged monitoring) and conventional home BP measurement.
This long-term assessment was planned after the initial study results through 18 months were analysed.
“Among 450 patients, 228 (mean [SD] age, 62.0 [11.7] years; 54.8% male) were randomised to the telemonitoring intervention and 222 (mean [SD] age, 60.2 [12.2] years; 55.9% male) to usual care,” the authors write.
“Research clinic BP measurements were obtained from 326 of 450 (72.4%) study patients at the 54-month follow-up visit, including 162 (mean [SD] age, 62.0 [11.1] years; 54.9% male) randomised to the telemonitoring intervention and 164 (mean [SD] age, 60.0 [11.2] years; 57.3% male) to usual care.
“Routine clinical care BP measurements were obtained from 439 of 450 (97.6%) study patients at 6248 visits during the follow-up period. Based on research clinic measurements, baseline mean SBP was 148 mm Hg in both groups.
“In the intervention group, mean SBP at 6-, 12-, 18-, and 54-month follow-up was 126.7, 125.7, 126.9, and 130.6 mm Hg, respectively. In the usual care group, mean SBP at 6-, 12-, 18-, and 54-month follow-up was 136.9, 134.8, 133.0, and 132.6 mm Hg, respectively.
“The differential reduction by study group in SBP from baseline to 54 months was −2.5 mm Hg (95% CI, −6.3 to 1.2 mm Hg; P = .18). The DBP followed a similar pattern, with a differential reduction by study group from baseline to 54 months of −1.0 mm Hg (95% CI, −3.2 to 1.2 mm Hg; P = .37). The SBP and DBP results from routine clinical measurements suggested significantly lower BP in the intervention group for up to 24 months.”
The authors concluded that intensive interventions like this can achieve substantial reductions in blood pressure, which have sustained effects for 24 months – 12 months after the intervention finished.
“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 authors write.
“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.”