Atrial fibrillation: an independent risk factor for nonaccidental falls in older patients.

BACKGROUND: Nonaccidental falls are often the result of a combination of factors including cardiovascular disorders such as orthostatic hypotension and unspecified cardiac arrhythmias. The objective of this study was to determine if there is an association between atrial fibrillation (AF) and nonaccidental falls. METHODS: We reviewed the records of 442 consecutive patients >65 years old who presented to the Emergency Department at the University of Utah Medical Center with a complaint of fall. RESULTS: Two-hundred eleven patients presented with nonaccidental fall, 231 patients with accidental fall. Patients with nonaccidental fall were more likely to be older, have a history of hypertension and neurological disorders, and taking five or more medications when compared to patients with accidental fall. Despite a similar prevalence of sinus rhythm at presentation, the prevalence of a history of AF was significantly higher in patients with nonaccidental fall compared to patients with accidental fall (26% vs 15%; P = 0.003). After adjusting for clinically and statistically significant predictors with a multivariate logistic regression analysis, AF, neurological disorders, and age ≤81 years were independent predictors of nonaccidental fall. In patients ≤81 years old (median age), the risk of nonaccidental falls was 2.5 times greater in patients with a history of AF when compared to those without a history of AF (odds ratio = 2.53 [confidence interval 95% 1.3-5], P = 0.007). CONCLUSION: AF is an independent risk factor for nonaccidental falls. Our results emphasize the need to screen for AF in patients presenting with nonaccidental fall.

Adenosine plasma level and A2A adenosine receptor expression: correlation with laboratory tests in patients with neurally mediated syncope.

OBJECTIVES: The purpose of this study was to investigate the hypothesis that responses to the ATP test and head-up tilt test (HUT) may be correlated with different purinergic profiles. DESIGN AND SETTING: The ATP and HUT identify distinct subsets of patients with neurally mediated syncope (NMS). Adenosine and its A(2A) receptors (A(2A)R) may be implicated in the pathophysiology of NMS in patients with positive HUT. Nothing is known about the purinergic profile of patients with positive ATP. PATIENTS AND MEASURES: This prospective study includes a consecutive series of patients with suspected NMS. All patients underwent both HUT and ATP. Before testing, samples were collected for measurement of baseline adenosine plasma level (APL) and expression. RESULTS: A total of 46 patients (25 men and 21 women) with a mean age of 57±18 years were enrolled. The HUT test was positive in 27 patients and the ATP test in 20. Both tests were positive in 9 and negative in 8. High APL was associated with high probability of positive HUT while low APL was associated with high probability of positive ATP. Expression of A(2A)R was lower in patients with positive ATP than in those with positive HUT. CONCLUSION: These findings indicate that patients with NMS present different purinergic profiles and that responses to HUT and ATP are correlated with these profiles.