https://immattersacp.org/weekly/archives/2018/03/06/5.htm

Self-monitoring of blood pressure led to better hypertension control than usual care

At 12 months, two intervention groups that self-monitored blood pressure had lower systolic blood pressure than a usual care group, with no significant difference between groups with and without telemonitoring.


Patients with hypertension who self-monitored their blood pressure had lower systolic blood pressure at 12 months than those measured in clinic, a randomized trial found.

At 138 general practices in the U.K., researchers enrolled patients who had medication-treated hypertension, were older than 35 years, had blood pressure higher than 140/90 mm Hg, and were willing to self-monitor their blood pressure. They randomized 1,182 participants to three groups: self-monitoring blood pressure (n=395), self-monitoring with telemonitoring (n=393), and usual care (clinic blood pressure; n=394).

In the self-monitoring group, patients used an automated electronic sphygmomanometer to measure their blood pressure twice each morning and evening for the first week of every month. They mailed their readings to their clinicians, who used the measurements to titrate antihypertensive medications. Patients in the telemonitoring group used a text service to report their readings to clinicians, who accessed them through a web interface. The primary outcome was systolic blood pressure, measured in clinic, 12 months after randomization.

Results were published online on Feb. 27 by The Lancet.

A total of 1,003 participants were included in the primary analysis. At 12 months, both intervention groups had lower systolic blood pressure than the usual care group (self-monitoring, 137.0 mm Hg and telemonitoring, 136.0 mm Hg vs. usual care, 140.4 mm Hg). The adjusted mean differences were −3.5 mm Hg (95% CI, −5.8 to −1.2 mm Hg; P=0.0029) between usual care and self-monitoring and −4.7 mm Hg (95% CI, −7.0 to −2.4 mm Hg; P<0.0001) between usual care and telemonitoring. There was no significant difference between the self-monitoring and telemonitoring groups.

At 12 months, patients in the usual-care group had been prescribed fewer medications than those in the self-monitoring group (1.63 antihypertensives vs. 1.55 antihypertensives; adjusted mean difference, 0.11; 95% CI, 0.02 to 0.19; P=0.0129) and those in the telemonitoring (1.70 antihypertensives vs. 1.55 antihypertensives; adjusted mean difference, 0.13; 95% CI, 0.04 to 0.21; P=0.0038).

The study authors noted limitations, such as how the majority of patients were of white British ethnicity, potentially limiting generalizability. In addition, an accompanying comment noted that it's unclear whether the results would be as robust if clinicians were caring for patients taking more than three antihypertensives, who were excluded.

“[T]hese results are important and reassuringly validate current clinical practice, as already applied to many individuals with hypertension worldwide. Although certainly not yet the norm, increasingly in many practices, patients bring in a more or less structured set of self-monitored blood pressure measurements on which physicians often base their therapeutic actions,” the comment authors wrote.

The March 2018 ACP Internist includes a story on managing hypertension, including information on patient self-monitoring.