Study finds masked and white coat hypertension prevalent and associated with higher risk of adverse cardiovascular events
Both white coat hypertension and masked hypertension were independently associated with increased biomarkers for organ damage, as well as higher risk of cardiovascular events compared with normal blood pressure, even after adjustment for traditional cardiovascular risk factors.
Masked hypertension and white coat hypertension were independently associated with cardiovascular events, according to a recent study.
Researchers looked at markers for organ damage and adverse cardiovascular outcomes associated with white coat hypertension (clinic BP ≥140/90 mm Hg, home BP <135/85 mm Hg), masked hypertension (home BP ≥135/85 mm Hg, clinic BP <140/90 mm Hg), and sustained hypertension (high home and clinic blood pressure) in the Dallas Heart Study, a large, multiethnic, probability-based population study.
The study cohort comprised 3,027 subjects (50% African-Americans). The sample-weighted prevalence rates of white coat hypertension and masked hypertension were 3.3% and 17.8%, respectively. Researchers assessed aortic pulsed-wave velocity by magnetic resonance imaging, urinary albumin-to-creatinine ratio, and cystatin C level at baseline, then followed patients for a median of 9 years to assess associations between white coat hypertension and masked hypertension and the outcomes of coronary heart disease, stroke, atrial fibrillation, heart failure, and cardiovascular death.
Study results appeared in the Nov. 17/24 Journal of the American College of Cardiology.
Over a median follow-up period of 9.4 years (interquartile range, 9.0 to 9.8 years), 47 cardiovascular deaths and 194 composite cardiovascular events were recorded. Both white coat hypertension and masked hypertension were independently associated with increased aortic pulsed-wave velocity, cystatin C level, and urinary albumin-to-creatinine ratio. Both white coat hypertension (adjusted hazard ratio [HR], 2.09; 95% CI, 1.05 to 4.15) and masked hypertension (adjusted HR, 2.03; 95% CI, 1.36 to 3.03) were independently associated with higher risk of cardiovascular events compared with normal BP, even after adjustment for traditional cardiovascular risk factors.
The authors noted that masked hypertension occurred in 14% of those not receiving antihypertensive treatment, comprising more than half of the hypertension cases in the cohort, and that white coat hypertension and masked hypertension were associated with markers of organ damage, including increased aortic stiffness and renal damage, as shown by albuminuria and higher cystatin C levels. The authors wrote, “Given the high prevalence of [masked hypertension] in our cohort, which could have been missed with office BP monitoring alone, the present study provides support for routine use of home BP monitoring in U.S. adults with and without antihypertensive drug treatment.”
An editorial noted that the risk for events was significantly higher in the masked hypertension and sustained hypertension groups compared with the normotensive group, whereas it barely approached significance (adjusted HR, 2.02; 95% CI, 1.01 to 4.03) in the white coat hypertension group. The editorial also noted that the study showed almost the same risk for events in the normotensive group and in the white coat hypertension group among non-African-American patients, whereas a significantly higher risk for events was found in the white coat hypertension group compared with the normotensive group in African-American patients.
The editorial cautioned, “From a practical standpoint, we have no evidence from controlled trials that patients with [masked hypertension] should be treated, or treated more aggressively to further lower their BP outside the office.”