Does masked hypertension exist in healthy volunteers and apparently well-controlled hypertensive patients?

BACKGROUND: Home blood pressure (HB P) measurement is considered to reflect BP during the day better than office BP (OB P). But in some patients HB P is higher than OB P. This is called masked hypertension (MH). OBJECTIVE: To examine whether MH occurs in healthy volunteers and apparently well-controlled hypertensives. METHODS: 57 treated hypertensive patients and 31 healthy volunteers (27/22 men) participated. Mean age (+/- SD ) was 61 +/- 13 and 29 +/- 13 years, respectively. Patients were instructed to measure their BP twice daily for three days (3 readings each) with the Omron 705 CP device after at least 10 minutes rest in a comfortable sitting position. In the outpatient department, OB P was measured four times, in duplicate, every ten minutes by the physician using the same device and under similar conditions. RESULTS: Mean HB P of the treated hypertensive group was 146/84 +/- 18/10 mmHg, significantly higher than OB P 136/79 +/- 19/10 (p