['To assess the association between impaired chronotropic response (CR) and adverse events among patients with diabetes referred for exercise treadmill testing (ETT).', "Impaired CR was defined as achievement of <80% of a patient's heart rate reserve. We used multivariable Cox proportional hazards regression to assess the independent association between impaired CR and adverse outcomes adjusting for demographics, comorbidities, and treadmill variables including the Duke Treadmill score.", 'Of 1,341 patients with diabetes, 35.7% (n = 479) demonstrated impaired CR during ETT. Patients with impaired CR were at increased risk of all-cause mortality, myocardial infarction, or coronary revascularization procedures. In multivariable analyses, impaired CR remained significantly associated with adverse outcomes (hazard ratio 1.53 [95% CI 1.10-2.14]).'] Does impaired chronotropic response to exercise stress testing in patients with diabetes predict future cardiovascular events?