Cardiac autonomic neuropathy (CAN) in type-1 diabetes mellitus patients and its association with the duration of disease and glycemic control.
OBJECTIVE
To determine the frequency of Cardiac Autonomic Neuropathy (CAN) in type-1 Diabetes mellitus patients and its association with the duration of disease and glycemic control.


METHODS
Descriptive study.


METHODS
Department of Medicine, Liaquat University Hospital, Hyderabad/Jamshoro, from December, 2004 to April, 2005.


METHODS
Fifty patients of type-1 Diabetes Mellitus (DM) of >or=10 years duration were selected. CAN was evaluated in terms of presence of resting tachycardia, loss of sinus arrhythmia and heart rate response to Valsalva maneuver by electrocardiogram (ECG). An R-R variation with respiration of >15 beats per minute was taken normal, while 10-15 beats and <10 beats per minute were taken as borderline and definitive CAN respectively. QTc intervals were measured. Patients with HbA1c levels<7% were considered as well-controlled. The associations between CAN, the duration of diabetes and the diabetic control were determined.


RESULTS
The mean age was 35.16+/-10.58 years with 32 males and 18 females. The mean values for the known duration of diabetes and HbA1c were 13+/-7.3 years and 9.36+/-2.5 mg/dl respectively. Definitive and borderline CAN were noted in 20% and 24% respectively. Variability of heart rate with respiration was significantly related to the duration but not to the control of the diabetes (p<0.05). QTc showed a significant correlation with the known duration of diabetes and heart rate variability with respiration (p<0.05). Most of the patients had uncontrolled glycemic status.


CONCLUSIONS
Cardiac autonomic neuropathy is common in long standing type-1 diabetics. CAN resulted in prolonged QTc interval that may result in cardiac arrhythmias and even death. Intensive glycemic control improves the cardiac autonomic nerve functions.
Department of Medicine, Muhammad Medical College, Mirpurkhas. drhajikhan786@yahoo.com
Haji Khan
HK
Khoharo
Shuaib
S
Ansari
Imran
I
Ali Shaikh
Fatima
F
Qureshi
D000328:Adult; D001342:Autonomic Nervous System Diseases / Q000453:epidemiology* / Q000503:physiopathology; D001794:Blood Pressure; D003922:Diabetes Mellitus, Type 1 / Q000150:complications* / Q000503:physiopathology / Q000628:therapy; D018450:Disease Progression; D004562:Electrocardiography; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006331:Heart Diseases / Q000453:epidemiology* / Q000503:physiopathology; D006339:Heart Rate; D006801:Humans; D008133:Long QT Syndrome / Q000453:epidemiology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010154:Pakistan / Q000453:epidemiology; D056152:Respiratory Rate; D012307:Risk Factors; D013997:Time Factors
D006442:Glycated Hemoglobin