A new study led by Marfella et al. has linked subclinical atrial fibrillation to patients with type 2 diabetes….
Approximately 25% of strokes experienced by type 2 diabetic patients are of unknown cause, however, a recent study is finding subclinical Afib as a possible "common etiologic factor." In the cohort designed study, 462 type 2 diabetic patients under the age of 60 were matched to "healthy controls" (patients without diabetes) to compare the prevalence of subclinical Afib. Episodes of subclinical Afib in patients were detected by having them monitored through a Holter, an ambulatory electrocardiography device, for the duration of 48 hours. Within 30 days after the Holter monitoring, patients were also scanned with an MRI of the brain to determine if silent cerebral infarcts (SCI) were occurring.
Diabetic patients demonstrated a higher prevalence of subclinical Afib episodes with 11% vs. 1.6% for the matched group. It was also reported that patients experiencing subclinical Afib were at an increased risk of silent cerebral infarcts (61% versus 29%) and strokes (17% versus 6%). About 41% of all diabetic patients in the study experienced silent cerebral infarcts compared to 0.5% of patients without diabetes.
Researchers found a significant relationship between the occurrence and size of SCI’s and the presence of asymptomatic Afib in patients. Moreover, all silent infarcts were lacunar in nature and less than 15 mm.
The average age of the participants in the study was 52, with a BMI of about 30 kg/m2, a mean blood pressure of about 130/79 mmHG, and a fasting blood glucose ~ 150 mg/dL in the diabetics and ~ 86 mg/dL in the healthy controls. During the first year of the study, patients were monitored for subclinical Afib every 3 months and then yearly for another 3 years.
Since screenings for Afib initially occurred at a quarterly interval, a limitation of the study was that not all subclinical Afib episodes might have been recorded.
Marfella R, et al "Brief episodes of silent atrial fibrillation predict clinical vascular brain disease in type 2 diabetic patients" J Am Coll Cardiol 2013; 62: 525-30