Refractory Hypertension: Prevalence And Patients Characteristics

Objective: To characterize the prevalence and the baseline profile of patients with refractory hypertension in a large cohort of resistant hypertensives. Design and method: A cross-sectional study evaluated 1048 patients [72% females, mean (SD) age: 61.2(11.3) years] referred for resistant hypertension (RHT) to a hypertension clinic. A total of 146 patients (13.9%) remained refractory (uncontrolled office blood pressure (BP) despite the use of at least 5 anti-hypertensive drug class) after a minimum 3 months follow-up period. All patients were submitted to a standard protocol that included a thorough clinical examination, laboratory evaluation, 24-hour ABPM, 2D echocardiography, and pulse wave velocity measurement. When suitable, T test, Mann Whitney or X2 test were done to compare patients with resistant and refractory hypertension. Results: Compared with RHT, patients with refractory hypertension were younger (58 [12] vs 62 [11] years, p = 0.002), more obese (59.6 vs 46.2%, p = 0.003) and most frequent smoking habits (15.1 vs 8.9%, p = 0.02). They presented a high prevalence of previous cerebrovascular diseases (21.9 vs 14.7%, p = 0.04), but no difference was found in relation to coronary or chronic kidney diseases. In subclinical lesions evaluation, patients with refractory hypertension presented more left ventricular hypertrophy (79% vs 70%, p = 0.04), but urinary albumin excretion rates and pulse wave velocity measurement were similar at baseline. Systolic and diastolic 24-hour BP was higher in refractory hypertensives (142 [19] vs 135 [18] and 82 [16] vs 78 [22], p < 0.001, respectively) but no difference was found in nocturnal BP profile. Conclusions: In a large cohort of patients with RHT, refractory hypertension had a high prevalence especially in younger patients and presented a closer correlation with a high cardiovascular risk profile.