Directly observed therapy for resistant/refractory hypertension diagnosis and blood pressure control

Objective: To test the impact of directly observed therapy (DOT) at hospital for checking not only adherence/diagnosis in patients with resistant (RHTN) and refractory (RefHTN) hypertension but also blood pressure (BP) control after hospital discharge.

Methods: During 2 years, Brazilian patients with clinical suspicion of RHTN/RefHTN after several attempts (≥3) to control BP in the outpatient setting were invited to perform DOT (including low-sodium diet and supervised medications intake) at the hospital. RHTN and RefHTN were categorised using standard definitions. After hospital discharge, we evaluated the BP values and the number of antihypertensive drugs prescribed by physicians who were not involved with the investigation.

Results: We studied 83 patients clinically suspected for RHTN (31%) and RefHTN (69%) (mean age: 53 years; 76% female; systolic BP 177±28 mm Hg and diastolic BP 106±21 mm Hg; number of antihypertensive drugs: 5.3±1.3). DOT confirmed RHTN in 77%, whereas RefHTN was confirmed in only 32.5%. The number of antihypertensive drugs reduced to 4.5±1.3 and systolic/diastolic BP at hospital discharge reduced to 131±17 mm Hg/80±12 mm Hg. After hospital discharge, systolic BP remained significantly lower than the last outpatient visit prehospital admission (delta changes (95% CI): 1 month: -25.7 (-33.8 to -17.6) mm Hg; 7 months: -27.3 (-35.5 to -19.1) mm Hg) despite fewer number of antihypertensive classes (1 month: -1.01 (-1.36 to -0.67); 7 months: -0.77 (-1.11 to -0.42)). Similar reductions were observed for diastolic BP.

Conclusions: DOT at hospital is helpful not only in confirming/excluding RHTN/RefHTN phenotypes, but also in improving BP values and BP control and in reducing the need for antihypertensive drugs after hospital discharge.