Reproducibility of masked uncontrolled hypertension detected through home blood pressure monitoring

Masked uncontrolled hypertension (MUCH) is an entity described in treated hypertensive subjects, where office blood pressure (BP) is well controlled and out-of-office BP is elevated. It has been related to a higher cardiovascular risk. However, the reproducibility of MUCH has been scarcely studied. In this study, we aimed to determine the reproducibility of MUCH detected through home blood pressure monitoring (HBPM). Two sets of measurements were performed in hypertensive adults under stable treatment with a 1-week interval. Each set of measurements included three office BP readings and a 4-day HBPM with duplicate readings in the morning, afternoon, and evening (the same validated oscillometric device was employed in both settings). We determined the percentage of agreement regarding the presence of MUCH in the two sets of measurements and quantified such agreement through the Cohen's kappa coefficient (κ), its 95% confidence interval, and P value. We included 105 patients (median age 58.6 [IQR 45.6-67.2] years old, 53.4% men). MUCH prevalence on at least one occasion was 22.3% (95% CI: 15.2-31.5). The reproducibility of MUCH was scant: κ = 0.19 (95% CI: 0.0002-0.38), P = 0.02, due to the poor reproducibility of the office BP component of MUCH in comparison with the home BP component: κ = 0.21 (95% CI: 0.03-0.39), P = 0.01 vs κ = 0.48 (95% CI 0.29-0.67), P < 0.001, respectively. In conclusion, the reproducibility of MUCH detected through HBPM is minimal, mainly due to the poor reproducibility of office BP measurements. An HBPM-based strategy for the management of patients with MUCH may be more adequate in terms of cardiovascular morbidity and mortality.