TREAT: A Multicentre Cross-sectional TReatment Evaluation of Apparent Resistant hyperTension in Belgium.

The goal of the TREAT study is to estimate the prevalence of true resistant hypertension in a Belgian setting of patients with apparent treatment resistant hypertension (aTRH) and to evaluate which determining factor of pseudo-resistant hypertension contributes the most to this prevalence. TREAT is a single-visit, multicentric, non-interventional, cross-sectional survey. Inclusion criteria included: patients over 18 years receiving 3 or more antihypertensive molecules and referred to specialized hospital centers for aTRH. A total of 201 eligible patients were included. Only 56.7% of the patients were treated with the guideline recommended triple combination therapy (i.e. renin-angiotensin-aldosterone system inhibitor, calcium channel blocker and thiazide (-like) diuretic), and only 23.4% were treated with the maximal recommended dose. WCH was present in 8.7% of the 115 patients with available ambulatory blood pressure recordings. Therapeutic adherence was self-reported as good by 80% of patients, while 20% reported poor or moderate adherence. In this cohort, the prevalence (95% CI) of true resistant hypertension was estimated at 21.9% (14.7%-30.6%). Among patients referred to specialized centers for aTRH, about 3 out of 4 presented with pseudo-resistant hypertension. The occurrence of WCH and poor adherence appeared rather limited in our study, but half of the participants were polymedicated with non-recommended combinations of antihypertensive molecules. Inadequate dosing was observed in the majority of patients and a third was not using a single pill combination. Hence, pseudo-resistant hypertension seems to be mainly associated with the underuse of triple combination therapy and, most likely, with suboptimal dosing.