Clinical Utility of Pre-Exercise Stress Testing in People With Diabetes

Abstract

BackgroundAlthough suggested by practice guidelines, the need for pre-exercise stress testing in asymptomatic people with diabetes remains controversial. We examined the utility of screening with pre-exercise stress testing in patients with diabetes. MethodsWe completed a cohort study, evaluating patients with diabetes who attended an exercise program intake session between 2007 and 2012. The exposure of interest was referral for pre-exercise stress testing determined by an algorithm requiring sedentary patients with diabetes and ≥ 1 cardiac risk factor to undergo testing. Outcomes included cardiac catheterization, revascularization, cardiovascular-related admissions, mortality, and change in care. ResultsAmong 1705 people with diabetes, 676 (40%) were referred for pre-exercise stress testing. In patients who were referred for stress testing compared with those who were not, there was no difference in the composite of cardiovascular outcomes (revascularization, cardiovascular-related admissions, and cardiovascular-related death) within 1 year (2.8% vs 1.9%, P = 0.250), or subsequent to the first year (3.1% vs 4.6%, P = 0.164). Within 1 year, more revascularizations were performed in patients referred for stress testing compared with those who were not (2.1% vs 0.8%, P = 0.027) but not during longer-term follow-up (mean 3.4 years). ConclusionsThe rates of cardiovascular outcomes in both tested and untested patients were low. Patients undergoing stress testing had no difference in adverse cardiovascular outcomes over the follow-up periods. Referral for stress testing did not result in a change in care for most patients. Our findings suggest stress testing before beginning an exercise program is not necessary for most asymptomatic patients with diabetes.