At-Home Blood Pressure Monitoring More Telling Than Doctor's Office Readings

MONDAY, June 27 (HealthDay News) — Blood pressure readings logged over a 24-hour period on a portable home monitoring device appear more effective than blood pressure readings taken in a doctor’s office for predicting whether patients with chronic kidney disease will experience kidney failure or death.

That’s the finding of an Italian study that included 436 chronic kidney disease patients who were not on dialysis.

In the study, each patient’s blood pressure was measured multiple times while at a clinic over the course of two days. They were also given an ambulatory blood pressure monitor that took readings every 15 minutes during the day and every half hour at night over a 24-hour period.

At-home blood pressure monitors are believed to help overcome what’s known as “white coat hypertension,” in which a patient’s blood pressure spikes because of stress and anxiety when visiting a physician’s office. According to background information in the article, chronic kidney disease patients are especially vulnerable to this.

Prior research has also suggested that nighttime blood pressure readings may be a better measure of a patient’s actual blood pressure status because readings are taken when the patient is at rest and free of the physical and emotional stresses of everyday life that can have an impact on readings.

During an average follow-up of 4.2 years, 86 patients developed kidney failure and 69 died. There were also 63 non-fatal cardiovascular events and 52 deaths caused by cardiovascular problems.

Patients with the highest risk of kidney or cardiovascular problems were those whose daytime systolic (top number) blood pressure was 135 mm Hg or higher; those with high diastolic (bottom number) readings; those with nighttime systolic readings of 124 mm Hg or higher; and those with nighttime diastolic readings of 70 mm Hg or higher. All these readings were provided by the ambulatory device.

“In contrast, office [blood pressure] measurements … did not predict cardiovascular or renal events,” the researchers wrote.

The study appears in the June issue of the journal Archives of Internal Medicine.

More information

The American Academy of Family Physicians has more about chronic kidney disease.