Objective: The clinical significance of masked and white-coat hypertension is still somewhat controversial. The aim of the present study was to investigate the prognosis of masked and white-coat hypertension using home blood pressure (BP) measurement.
Design and methods: A nationwide population sample (n = 2046, age 44-74 years) underwent office (duplicate measurements on one visit by a nurse) and home (duplicate measurements on 7 days) BP measurements and risk factor evaluation. During the follow-up of 7.5 years, 221 fatal and nonfatal cardiovascular events and 142 all-cause deaths occurred. Masked hypertension was defined as office BP less than 140/90 mmHg with home BP at least 135/85 mmHg.
Results: The prevalence of baseline risk factors and the incidence of cardiovascular events and all-cause deaths increased from normotension to white-coat, masked and sustained hypertension. Unadjusted hazard ratios for white-coat hypertension were 1.18 (P = 0.5) for cardiovascular events and 1.23 (P = 0.5) for all-cause deaths. Masked hypertension had a significantly higher age-adjusted risk of cardiovascular events and a higher risk of all-cause mortality after adjustment for age, sex and office BP than normotension (hazard ratios 1.64, P = 0.05, and 2.09, P = 0.01). Masked hypertension lost its predictive significance after adjustment for home BP or concomitant other cardiovascular risk factors.
Conclusion: Neither masked nor white-coat hypertension was an independent predictor of cardiovascular risk or all-cause mortality when concomitant other risk factors or baseline home BP levels were taken into account. The present study suggests that home BP level, along with other traditional risk factors, may be enough to stratify cardiovascular risk.