Progression of cardiovascular autonomic dysfunction in patients with type 2 diabetes: a 7-year follow-up study.
OBJECTIVE
We investigated whether cardiovascular autonomic dysfunction was associated with glycemic control status over time in patients with type 2 diabetes.


METHODS
From 1999 to 2000, cardiovascular autonomic nerve function testing (AFT) was performed on patients with type 2 diabetes (n = 1,021) and was followed-up in 2006 and February 2008. Tests for cardiovascular autonomic functions measured heart rate variability parameters (expiration-to-inspiration [E/I] ratio, responses to the Valsalva maneuver, and standing). AFT scores were determined from the results of the each test as follows: 0 for normal and 1 for abnormal. We began with those who had a score of 0 and assessed the changes in total score along with biannual A1C levels.


RESULTS
At follow-up, the development of cardiovascular autonomic dysfunction was 34.5% (E/I ratio 21.9%, Valsalva maneuver 77.8%, and posture 58.9%; n = 783). The development of cardiovascular autonomic dysfunction was higher in older patients (P < 0.001); in those with longer duration of diabetes (P < 0.001); of hypertension (P = 0.005), and of diabetic retinopathy (P < 0.001); and in those who had higher levels of microalbuminuria (P = 0.002). Logistic regression analysis revealed that the development of cardiovascular autonomic dysfunction was strongly associated with the mean A1C level during the follow-up period (mean A1C >9.0% vs. <or=7.0%, odds ratio 2.984, 95% CI 1.177-7.561; P = 0.021).


CONCLUSIONS
The development of cardiovascular autonomic dysfunction was independently associated with microvascular complications and glycemic control status during this 7.5-year follow-up in patients with type 2 diabetes.
Division of Endocrinology and Metabolism, Department of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
Seung-Hyun
SH
Ko
Shin-Ae
SA
Park
Jae-Hyoung
JH
Cho
Ki-Ho
KH
Song
Kun-Ho
KH
Yoon
Bong-Yun
BY
Cha
Ho-Young
HY
Son
Ki-Dong
KD
Yoo
Keon-Woong
KW
Moon
Yong-Moon
YM
Park
Yu-Bai
YB
Ahn
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000503:physiopathology*; D003925:Diabetic Angiopathies / Q000503:physiopathology*; D003929:Diabetic Neuropathies / Q000503:physiopathology*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011187:Posture; D012044:Regression Analysis; D013997:Time Factors; D014636:Valsalva Maneuver
D001786:Blood Glucose