Determinants of masked hypertension in the general population

Introduction Home blood pressure (BP) measurement has allowed the identification of individuals with normal office and elevated out-of-office BP (masked hypertension). It is, however, not feasible to measure home BP on all office normotensive individuals. The objective of the present study was to identify demographic, lifestyle, clinical and psychological characteristics suggestive of masked hypertension. Methods Study population was drawn from the participants of a multidisciplinary epidemiological survey, the Health 2000 Study. The untreated nationwide population sample (n = 1459, age 45–74 years) underwent office (duplicate measurements on one visit) and home (duplicate measurements on 7 days) BP measurements and risk factor evaluation. Psychometric tests assessed psychological distress, hypochondriasis, depression and alexithymia. Masked hypertension was defined as normal office BP (<140/90 mmHg) with elevated home BP (≥135/85 mmHg). Results The prevalence of masked hypertension was 8.1% in the untreated Finnish adult population. The cardiovascular risk profile of masked hypertensive patients resembled that of sustained hypertensive patients. High-normal systolic and diastolic office BP, older age, greater BMI, current smoking, excessive alcohol consumption, diabetes and electrocardiographic left-ventricular hypertrophy were independent determinants of masked hypertension in multivariate logistic regression analysis. Masked hypertension was also independently associated with hypochondria. Conclusion Masked hypertension is a common phenomenon in an untreated adult population. Physicians should consider home BP measurement if a patient has high-normal office BP, diabetes, left-ventricular hypertrophy, or several other conventional cardiovascular risk factors.