Incidence and risk factors for non-cardiac syncope in a cohort of patients addressing an accredited Arterial Hypertension Center: the Innocent Study.

Background: Hypotensive susceptibility in hypertensive patients could facilitate orthostatic hypotension, syncope and fall. The aim of this study was to identify incidence, clinical form, complications and risk factors for non-cardiac syncope in a cohort of hypertensive patients.

Methods: This is an observational, case-controlled, retrospective study carried out on 168 patients, evaluated at the Hypertension Center of the University Hospital of Parma (Italy). Based on the presence of episodes of syncope during the six months prior to enrolment, we identified cases and controls and then we compared them to personal data, comorbidities, current drug regimens, presence of orthostatic hypotension, office and ambulatory blood pressure monitoring (ABPM) blood pressure (BP) values.

Results: In patients with previous syncopal episodes (29.8% of total), we more frequently found female gender, comorbidities associated with autonomic dysfunction, diuretics and non-CV drugs potentially associated with hypotension in their current drug regimen, orthostatic hypotension and lower office and ABPM BP values.

Conclusions: To identify hypertensive patients at higher risk for syncope and falls, physicians should focus on comorbidities and current drug regimens, systematically perform an active standing test to identify orthostatic hypotension, employ ABPM to compare BP values with the pre-established target and highlight systolic BP drops and abnormalities suggesting concomitant autonomic dysfunction. The modulation of antihypertensive therapy is an effective tool to counteract the risk of non-cardiac syncope, with possible trauma or other negative influences.