SAN FRANCISCO — New data for the first time support assumptions that home monitoring improves blood pressure control because of better adherence to antihypertensive therapy, Gbenga Ogedegbe, M.D., said at the annual meeting of the American Society of Hypertension.
Previous reports showed better control in hypertensive patients performing home blood pressure monitoring, compared with patients monitored in physicians' offices, and clinicians assumed this was due to better adherence to therapy with home monitoring.
The current data—part of a larger and longer study—came from patients with uncontrolled blood pressure on one or more antihypertensive medications who were randomized to home blood pressure monitoring (118 patients) or usual care in offices (60 patients) for 12 weeks. Investigators assessed adherence to therapy using the well-validated Morisky questionnaire, said Dr. Ogedegbe of Columbia University, New York.
At baseline, 47% of patients in the home monitoring group and 65% in the usual care group reported being adherent to therapy, a difference that was not statistically significant.
In the home monitoring group, the patients took their blood pressure three times per week on average, usually at different times of the day, using a “life-link” monitoring system that gave them immediate feedback on their blood pressure control (or lack of it) and electronically sent a report to their physicians.
At follow-up 12 weeks later, patients were asked four questions that have been shown to predict the likelihood of blood pressure control: In the past 4 weeks, have you been careless about taking your blood pressure medication? In the past 4 weeks, have you forgotten to take your blood pressure medication? Do you stop taking the medication when you feel better? Do you stop taking the medication when you feel worse, from side effects? Patients who answered “yes” to any of the questions were considered nonadherent to therapy.
In the home monitoring group, 31% went from being nonadherent at baseline to adherent with therapy at 12 weeks, compared with 12% of patients in the usual care group, a significant difference.
Patients in the home monitoring group were less likely to move from adherent to nonadherent (12%), compared with the usual care group (18%). The rest did not change adherence patterns.
The study was not large enough to detect any significant changes in blood pressure, Dr. Ogedegbe said.