White-coat and masked hypertension as risk factors for progression to sustained hypertension: the Finn-Home study

To assess the risk of progression from white-coat hypertension (WCHT) and masked hypertension (MHT) to sustained hypertension (SHT) in a nationwide unselected population sample.

Both office and home blood pressure (BP), along with other cardiovascular risk factors, were measured in an unselected population sample of 944 participants in 2000 and 2011. We compared the risk of progression to SHT (office BP ≥140/90 mmHg and home BP ≥135/85 mmHg or start of treatment with antihypertensive medication) between 528 participants with normotension (office BP <140/90 mmHg and home BP <135/85 mmHg), 142 participants with WCHT (office BP ≥140/90 mmHg and home BP < 135/85 mmHg), and 63 participants with MHT (office BP < 140/90 mmHg and home BP ≥135/85 mmHg) at baseline. We used the χ test and a multivariable-adjusted log-binomial regression model to evaluate the association between baseline BP categories and incident SHT.

During an 11-year follow-up, the rate of progression to SHT increased from normotension (18%) to WCHT (52%) and MHT (73%), P < 0.0001. Progression to SHT became more likely with an increasing baseline home BP category (Ptrend < 0.0001). The multivariable-adjusted relative risks (95% confidence interval) for developing SHT, as compared with normotension, were 2.8 (2.2-3.6, P < 0.0001) for WCHT and 3.8 (2.9-5.0, P < 0.0001) for MHT.

Persons with WCHT and MHT have a three to four-fold risk for developing SHT than those with NT and could benefit from active follow-up and lifestyle counselling.