The prognostic relevance of masked uncontrolled hypertension (MUCH) is incompletely clear, and its global impact on cardiovascular outcomes and mortality has not been assessed. The aim of this study was to perform a meta-analysis on the prognostic value of MUCH. We searched for articles assessing outcome in patients with MUCH compared with those with controlled hypertension (CH) and reporting adjusted hazard ratio and 95% CI. We identified 6 studies using ambulatory blood pressure monitoring (12 610 patients with 933 events) and 5 using home blood pressure measurement (17 742 patients with 394 events). The global population included 30 352 patients who experienced 1327 events. Selected studies had cardiovascular outcomes and all-cause mortality as primary outcome, and the main result is a composite of these events. The overall adjusted hazard ratio was 1.80 (95% CI, 1.57-2.06) for MUCH versus CH. Subgroup meta-analysis showed that adjusted hazard ratio was 1.83 (95% CI, 1.52-2.21) in studies using ambulatory blood pressure monitoring and 1.75 (95% CI, 1.38-2.20) in those using home blood pressure measurement. Risk was significantly higher in MUCH than in CH independently of follow-up length and types of studied events. MUCH was at significantly higher risk than CH in all ethnic groups, but the highest hazard ratio was found in studies, including black patients. Risk of cardiovascular events and all-cause mortality is significantly higher in patients with MUCH than in those with CH. MUCH detected by ambulatory or home blood pressure measurement seems to convey similar prognostic information.
Keywords: blood pressure; hypertension; masked hypertension; mortality; risk.