Article

Autonomic control of the cardiovascular system may be impaired in
type 2 diabetes and is associated with increased morbidity and mortality.
Parameters obtained during stress testing may reflect early stages of cardiac
autonomic dysfunction and provide prognostic information in asymptomatic type 2
diabetes. METHODS: We performed maximal exercise treadmill testing in 594
patients with type 2 diabetes without known coronary heart disease. The
prognostic significance of physiological parameters associated with autonomic
dysfunction was assessed, including chronotropic incompetence (<80% heart rate
reserve), abnormal heart rate recovery at 1 minute <18 beats/minute, and resting
tachycardia >100 beats/minute. Cox proportional hazards analysis was used to
determine the association of exercise parameters with a composite outcome of
all-cause mortality, myocardial infarction or stroke. RESULTS: Resting heart rate
>100 beats/minute was observed in 18% of patients, chronotropic incompetence in
30% and heart rate recovery at 1 minute <18 beats/minute in 35%. Over 79 +/- 16
months, there were 72 (12%) events. Each parameter was significantly associated
with event risk in an adjusted multivariate analysis: chronotropic incompetence
(hazard ratio 1.89, 95% confidence interval 1.18-3.01; P = 0.008), resting heart
rate >/=100 beats/minute (hazard ratio 1.97, 95% confidence interval 1.19-3.26; P
= 0.008) and heart rate recovery at 1 minute <18 beats (hazard ratio 1.77, 95%
confidence interval 1.12-2.81; P = 0.015). A progressive relationship between the
number of abnormal parameters and event risk was observed (log rank P < 0.001).
CONCLUSIONS: Chronotropic incompetence, resting tachycardia and reduced heart
rate recovery are independently and additively associated with long-term
mortality, myocardial infarction or stroke in type 2 diabetes without known
coronary heart disease.
CI - (c) The European Society of Cardiology 2015.

Langue : ANGLAIS