Introduction: Hypertensive patients with poor blood pressure (BP) control are commonly referred to tertiary centers with a diagnosis of resistant hypertension (RH). The aim of the study was to identify the causes of insufficient BP control and to assess the incidence of true resistant hypertension.
Material and methods: We ran a questionnaire-based, multicenter study (10 high volume tertiary centers in Poland) of patients referred with an initial diagnosis of RH. Only patients with ABPM-confirmed uncontrolled hypertension (systolic ≥140 mmHg and/or diastolic ≥90mmHg despite maximal doses of ≥3 medications, including a diuretic) were included. We assessed the causes of non-optimal BP control, a proportion of patients with excluded secondary hypertension, and the burden of hypertension-related complications.
Results: We analyzed 124 patients aged 41-88, with a history of hypertension of 17.5±9 years. 90% of them had developed systemic complications, the most common being LV hypertrophy (73.4%) and LV diastolic dysfunction (63.4%). In only 47% all major causes of secondary hypertension were excluded. In 90.3% of subjects, at least one factor affecting BP control was identified. The most frequent factors were medication noncompliance (52.4%), metabolic syndrome (43.6%) excessive sodium intake (66.1%) and chronic administration of non-steroid anti-inflammatory drugs (40%). The incidence of real resistant hypertension was only 4.8%.
Conclusions: Among patients referred with uncontrolled hypertension, the incidence of real resistant hypertension is small. A majority of these patients have multiple factors potentially responsible for poor BP control, the most common being medication non-adherence, use of drugs increasing BP, excessive salt intake and metabolic syndrome.
Keywords: resistant hypertension; pseudo-resistant hypertension; non-compliance.