Home-Based and Office Blood Pressure Measurement Complementary
A study that compared self-measurement with office measurement of blood pressure has concluded that office measurement using conventional sphygmomanometry remains key to the diagnosis and management of hypertension, although self measurement and ambulatory monitoring are useful to confirm the diagnosis and to diagnose white coat or masked hypertension. The Treatment of Hypertension Based on Home or Office Blood Pressure (THOP) trial was carried out mainly in Belgium (56 primary care practices plus 3 hospital-based outpatient clinics plus 1 specialized hypertension clinic in Dublin, Ireland). Four hundred patients with a DBP of ≥ 95 mm Hg were enrolled between March 1997 and April 2002, randomized to treatment based on their blood pressure measured at home vs the physician's office, and followed for 1 year.
The target for all patients was a DBP of 80-89 mm Hg. After randomization, patients were started on an ACE inhibitor, lisinopril 10 mg/day (Step 1). Based on whether self-measured DBP (average of 6 measurements per day during one week) or office DBP (average of 3 sitting DBP measurements) was above, at, or below target, treatment was intensified in a stepwise manner:
Step 2: lisinopril 20 mg/day
Step 3: lisinopril 20 mg/day + hydrochlorothiazide 25 mg/day or amlodipine 5 mg/day
Step 4: lisinopril 20 mg/day + hydrochlorothiazide 25 mg/day + amlodipine 5 mg/day; or lisinopril 20 mg/day + amlodipine 5 mg/day + prazosin ≤ 6 mg/day
A beta-blocker, atenolol 50 mg (Step 1) and 100 mg/day (Steps 2-4), was substituted for lisinopril in patients who were ACE-inhibitor intolerant.
At the end of follow-up, more patients in the home blood pressure measurement group had stopped antihypertensive drug treatment than in the office measurement group (25.6% vs 11.3%, P < .001), incurring lower related healthcare costs. However, blood pressure was less well controlled in the home measurement group, which had higher final blood pressure measurements than the office measurement group (SBP/DBP on average 6.8/3.5 mm Hg higher by conventional measurement at the physician's office and 4.9/2.9 mm Hg higher by home measurement). Final 24-hour ambulatory blood pressure measurements were also higher in the home measurement group. There were no differences between the 2 groups in terms of overall feelings of well-being or with regard to left ventricular mass.
On the basis of their findings, the THOP trial investigators conclude that the management of hypertension based exclusively on home blood pressure measurements cannot be recommended until prospective studies have been done to establish the normal range of home blood pressure and the thresholds at which drug treatment should be started or stopped.
Medscape Cardiology. 2004;8(1) © 2004 Medscape
Cite this: Hypertension, But not "Prehypertension," Increases Stroke Risk -- and Should Combination Therapy Include a Calcium Antagonist? - Medscape - Mar 17, 2004.