title: Brief episodes of silent atrial fibrillation predict clinical vascular brain disease in type 2 diabetic patients.
abstract: OBJECTIVE
  This study evaluated whether subclinical episodes of atrial fibrillation (AF) were associated with an increased risk of silent cerebral infarct (SCI) and stroke in diabetic patients younger than 60 years who did not have other clinical evidence of AF and cerebrovascular disease at baseline.
  
  
  BACKGROUND
  In type 2 diabetic patients, one-fourth of strokes are of unknown cause, and subclinical episodes of AF may be a common etiologic factor.
  
  
  METHODS
  A total of 464 type 2 diabetic patients younger than 60 years were included in a longitudinal observational study and matched to patients without diabetes. Patients underwent 48-h electrocardiographic Holter monitoring quarterly to detect brief subclinical episodes of AF (duration of AF <48 h) and were followed up for 37 months. The outcomes were SCI, assessed by magnetic resonance imaging of the brain, and stroke events during the follow-up period.
  
  
  RESULTS
  The prevalence of subclinical episodes of AF was significantly greater among patients with diabetes compared with matched healthy subjects (11% vs. 1.6%, p < 0.0001). During an average duration of 37 months, 43 stroke events occurred in the diabetic population and no events occurred in healthy subjects. Diabetic patients with silent episodes of AF (n = 176) had a higher baseline prevalence of SCI (61% vs. 29%; p < 0.01) and a higher number of stroke events (17.3% vs. 5.9%; p < 0.01) during the follow-up period than the other patients (n = 288). An episode of silent AF was an independent determinant of SCI (odds ratio: 4.441; p < 0.001; confidence interval: 2.42 to 8.16) and an independent predictor of the occurrence of stroke in diabetic patients (hazard ratio: 4.6; p < 0.01; confidence interval: 2.7 to 9.1).
  
  
  CONCLUSIONS
  Subclinical episodes of AF occurred frequently in type 2 diabetic patients and were associated with a significantly increased risk of SCI and stroke.
authors.affiliation: Department of Geriatrics and Metabolic Diseases, Second University of Naples, Piazza Miraglia 2, Naples, Italy. raffaele.marfella@unina2.it
authors.forename: Raffaele
authors.initials: R
authors.lastname: Marfella
authors.forename: Ferdinando Carlo
authors.initials: FC
authors.lastname: Sasso
authors.forename: Mario
authors.initials: M
authors.lastname: Siniscalchi
authors.forename: Mario
authors.initials: M
authors.lastname: Cirillo
authors.forename: Pasquale
authors.initials: P
authors.lastname: Paolisso
authors.forename: Celestino
authors.initials: C
authors.lastname: Sardu
authors.forename: Michelangela
authors.initials: M
authors.lastname: Barbieri
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Rizzo
authors.forename: Ciro
authors.initials: C
authors.lastname: Mauro
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Paolisso
mesh_terms: D001281:Atrial Fibrillation / Q000150:complications* / Q000175:diagnosis; D016022:Case-Control Studies; D002544:Cerebral Infarction / Q000175:diagnosis / Q000209:etiology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000175:diagnosis; D015716:Electrocardiography, Ambulatory; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000175:diagnosis / Q000209:etiology*
keywords: 48-h electrocardiographic Holter monitoring; 48HM; AF; CI; ECG; HR; MRI; OR; SCI; atrial fibrillation; cerebrovascular disease; confidence interval; diabetes; electrocardiographic; hazard ratio; magnetic resonance imaging; odds ratio; silent cerebral infarct