Results of studies using self-reporting of blood pressure measurement by way of telecommunication systems have demonstrated declines in both systolic and diastolic blood pressure, but patients are known to often report inaccurate blood pressures, especially when the blood pressure is high. Rogers and associates conducted a randomized, controlled trial that used 24-hour ambulatory blood pressure monitoring measurements to more accurately identify changes in blood pressure and reported these results by electronic transmission to physicians.
Patients with essential hypertension were included in the study if they were being considered for a change in antihypertensive therapy because of elevated blood pressure despite antihypertensive treatment; adverse side effects from hypertensive medication; an office systolic pressure of at least 180 mmHg or a diastolic pressure of at least 110 mmHg, and no current use of antihypertensive agents. All patients received printed material on nonpharmacologic approaches to blood pressure control including weight reduction, increased physical activity and a change in diet, when necessary. Baseline height, weight, and body mass index were recorded.
Of the 121 patients in the trial, 60 were randomly assigned to the home-service group and 61 to the usual-care group. The intervention was automatic blood pressure recording at home. Patients in the intervention group took their blood pressure three times in the morning before eating or drinking and three times in the evening before going to bed at least three times weekly for a minimum of eight weeks. Data were automatically transmitted to a support center at Welch Allyn, the manufacturer of the telecommunication devices. Weekly reporting of systolic and diastolic pressures and heart rate was provided to both the primary physician and the patient. Physicians adjusted medications by telephone or office visit.
The usual-care group had no home blood pressure monitoring. The primary study end point was change in mean arterial pressure during the trials. This was obtained using a 24-hour ambulatory blood pressure monitoring device at baseline and at the conclusion of the study. The median time of the study was 11 weeks.
The mean arterial blood pressure decreased in patients receiving the home service regardless of gender, age, or ethnicity. Medication changes were significantly more common in the study (home-service) group, but the mean decrease in arterial pressure was not related to a medication change.
The authors conclude that patients with essential hypertension who use a telecommunication service to report measurements have a greater decrease in blood pressure than patients receiving usual care. Part of this beneficial effect may have been caused by more frequent medication changes, but blood pressure also decreased in home-service patients who did not have a change of medication. Patients may have been more motivated to make healthy lifestyle changes or were more adherent to their medication regimens when they were able to see their pressure readings on the home device.