Correlation of altered Q-T interval and sympathetic nervous system dysfunction in diabetic autonomic neuropathy.
We examined the relationship between the Q-T interval and autonomic dysfunction in 74 diabetic patients and age-matched controls. The expected Q-T interval was standardized as a function of the R-R interval in 646 healthy controls, and the delta Q-T defined as the difference from the expected value. Propranolol increased delta Q-T, confirming this as a parameter of autonomic function. No relationship between delta Q-T and duration of disease, glucose control, retinopathy or proteinuria was observed. However, significant correlations were found between the delta Q-T and delay of nerve conduction velocity, orthostatic hypotension, altered Valsalva ratio, abnormal Valsalva overshoot, cold pressor response, decreased norepinephrine concentration and sympathetic function score in diabetic patients.
Oka
H
H
Third Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan.
Mochio
S
S
Sato
K
K
Isogai
Y
Y
D000328:Adult; D001342:Autonomic Nervous System Diseases / Q000175:diagnosis / Q000503:physiopathology*; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure / Q000502:physiology; D003929:Diabetic Neuropathies / Q000175:diagnosis / Q000503:physiopathology*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008133:Long QT Syndrome / Q000175:diagnosis / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood; D012016:Reference Values; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D014636:Valsalva Maneuver / Q000502:physiology
D001786:Blood Glucose; D009638:Norepinephrine