Abstract 17839: Predictors of New Nonfatal Cardiac Events in Apparently Healthy Patients with Type 2 Diabetes with Negative Stress Echocardiogram

Abstract

Background: Pts with Type 2 diabetes (DM) who have a negative stress echo (ExE), remain at higher risk for new cardiac events, compared to non-DM. We sought the predictive role of previously diagnosed obstructive sleep apnea (OSA) on 5-year incident heart failure (HF), coronary artery disease (CAD), and atrial fibrillation (AF) in DM, in a routine clinical setting.

Methods: We studied 901 consecutive pts with DM (age 56±11y, 403 women), without HF, chest pain, AF, cardiac surgery, valvular heart disease, ejection fraction <50%, or CAD, who underwent a negative ExE between 2004 and 2007. Data were collected prospectively, including demographics, BMI, Duke Treadmill score, indications for ExE, cardiac risk factors, symptoms, heart rate, blood pressure, prior diagnoses and medications. Nested Cox proportional hazards models were used to identify predictors of incident HF, CAD and AF.

Results: 188 pts (21%) had diagnosed OSA but only 72 (38%) were using continuous positive airway pressure (CPAP). Over 4.7±1.5 yrs, 22 (2.6%) pts developed new HF, 72 (8.6%) new CAD and 40 (4.8 %) new AF. OSA showed significant association with incident CAD (age adjusted HR=2.6 [1.5-4.5], p<0.001) and AF (age adjusted HR=2.9 [1.5-5.8], p=0.002) and marginal association with incident HF (age adjusted HR=2.4 [0.97-5.8], p=0.06) in unadjusted and adjusted models (table), while overweight/obesity was not predictive for incident cardiac events. Resting systolic blood pressure was a significant predictor of all new cardiac events (HF, CAD, AF) while female gender was a significant predictor of new CAD events.

Conclusions: OSA in apparently healthy pts with DM with a negative ExE predicts higher risk of incident cardiac events over 5 years, independently of known risk factors.