Prevalence of resistant hypertension in non-elderly adults: prospective study in a clinical setting

In face of variable definitions and sampling criteria, the real prevalence of resistant hypertension in a clinical setting is unknown.

We investigated the prevalence of true resistant hypertension in an outpatient hypertension clinic.

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.

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/m² 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%.

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.