Treatment of Resistant Hypertension: Cohort Study

This is a multicenter, prospective observational cohort study. It will compare effectiveness and safety of various add-on treatment options in regard to arterial blood pressure control in adult patients with treatment resistant hypertension: an aldosterone receptor blocker (e.g. spironolactone), a loop diuretic, a thiazide in large daily dose, an alpha 1 selective blocker or a beta 1 selective blocker. The add-on therapy will be prescribed to the patients within the scope of their routine medical care, independently from the study investigators. The patients will be followed up for 6 months, with monthly visits and continuous home blood pressure diary kept by the patients themselves.