Prevalence of masked hypertension (MH) is far from negligible reaching 40% in some studies. The SHEAF study (Self measurement of blood pressure at Home in the Elderly: Assessment and Follow-Up) and others clearly showed that masked hypertension (MH) as detected by home blood pressure measurement (HBPM) is associated with poor cardiovascular prognosis.
Systematic HBPM to detect MH is not yet routine. The aim of this work is to better define the clinical profile of masked hypertensives within a population with controlled office blood pressure (BP) and the factors associated with a higher prevalence of MH.
Materials and methods
BP was measured at the clinic by the doctor and at home by the patient himself. Risk factors for MH were analysed in a cohort of 1150 treated hypertensive patients over the age of 60 (mean age 70 ± 6.5, 48.9% men) with controlled office BP. (SBP <140 mmHg and DBP <90 mmHg).
463 patients (40%) were masked hypertensives (SBP≥135 mmHg or DBP≥85 mmHg at home). Three parameters were associated with MH (odds ratio OR): office SBP (OR = 1.110), male gender (OR = 2.214) and age (OR = 1.031). Decision trees showed a 130 mmHg SBP was an efficient threshold to propose HBPM with a higher probability to detect MH. Subsequent variables were male gender and age over 70 in males.
To detect masked hypertension, it would be logical to first of all select patients whose office SBP is between 130 and 140 mmHg.