Abstract 14503: Patterns of Exposure to Resistant Hypertension and Cardiovascular Morbidity: A 4-Year Prospective Study

Introduction: Even though resistant hypertension (RHT) is a frequent clinical condition, little is known regarding its clinical course and prognosis. Hypothesis: We investigated the associated cardiovascular risk of diverse patterns of RHT evolution. Methods: In a prospective observational study, 1911 treated hypertensive patients (aged 59±11 years, 49% males) were followed for a mean period of 3.9±1.7 years. At baseline, clinical data were collected and patients underwent echocardiographic measurements, routine blood testing and additional workup for exclusion of secondary causes of RHT. Four groups were identified depending on presence or absence of RHT (office-based uncontrolled hypertension under at least 3 drugs including a diuretic or controlled hypertension under 4 or more drugs) at baseline and follow-up: 1,153 patients (60%) never having RHT, 189 (10%) with resolved RHT, 204 (11%) with incident RHT and 365 (19%) with persistent RHT. Endpoint of interest was cardiovascular morbidity set as the composite of coronary heart disease and stroke. Results: During follow-up, 65 events occurred (9.7 cases per 1,000 person-years). Incidence rates of cardiovascular events were 6.4 cases per 1,000 person-years in the never having RHT group, 9.1 cases per 1,000 person-years in the resolved RHT group, 13.2 cases per 1,000 person-years in the incident RHT group and 18.1 cases per 1,000 person-years in the persistent RHT group. Unadjusted analysis showed that patients with persistent RHT exhibited a significantly higher risk by 2.5 times (CI:1.42-4.36, p=0.002) for the composite cardiovascular outcome compared with the never having RHT group, while there was a gradually higher risk in patients with resolved and incident RHT that did not reach statistical significance. After adjusting for a series of established risk factors, persistent RHT remained as an independent predictor of the cardiovascular outcome, associated with a more than twofold risk (OR:2.2, CI:1.21-4.05, p=0.01) Conclusions: In treated hypertensive patients, persistence of RHT is frequent and independently associated with adverse cardiovascular prognosis.