Prevalence of Resistant Hypertension in Non-Elderly Adults: Prospective Study in a Clinical Setting

Background: In face of variable definitions and sampling criteria, the real prevalence of resistant hypertension in a clinical setting is unknown. Objective: We investigated the prevalence of true resistant hypertension in an outpatient hypertension clinic. Methods: True resistant hypertension was diagnosed when white coat phenomenon, lack of compliance and secondary hypertension were excluded in patients with blood pressure >= 140/90 mmHg in two consecutive visits, despite to be using three blood pressure-lowering agents, including a diuretic. Results: In the total, 606 patients, with 35 to 65 years of age, mostly women, with BP of 156.8 +/- 23.8 mmHg by 91.9 +/- 15.6 mmHg and a BMI of 29.7 +/- 5.9 Kg/m(2) were sequentially evaluated. One hundred and six patients using three BP drugs had uncontrolled blood pressure (17.5% of the whole sample) in the first visit. Eighty-six patients (81% of the patients with uncontrolled BP in the first evaluation) returned for the confirmatory evaluation. Twenty-five had controlled BP, 21 had evidence of low adherence to treatment, 13 had white coat phenomenon and 9 had secondary hypertension, leaving only 18 patients (20.9% of those uncontrolled in the confirmatory visit and 3% of the whole sample) with true resistant hypertension. Considering patients with secondary hypertension as cases of resistant hypertension, the prevalence of resistant hypertension increased to 4.5%. Conclusion: The frequency of patients with true resistant hypertension in non-elderly patients is low in a clinical setting, and is not substantially increased with the inclusion of patients with secondary hypertension. (Arq Bras Cardiol 2012;99(1):630-635)