Relationships between heart rate variability and urinary albumin excretion in patients with type 2 diabetes.
BACKGROUND
Although in type 1 diabetes the close association between heart rate variability and urinary albumin excretion (UAE) is recognized even in patients with normoalbuminuria, this association has not yet been fully established in patients with type 2 diabetes. Therefore, we investigated the association in patients with type 2 diabetes.


METHODS
All the hospital's 185 inpatients with type 2 diabetes were prospectively enrolled. Heart rate variability was evaluated by coefficients of variance of RR intervals (CVRR).


RESULTS
The mean age, duration of diabetes, and hemoglobin A1C of the patients were 59.7+/-9.9 years, 10.4+/-7.8 years, and 9.7+/-2.3%, respectively. An analysis of the patients showed a significant negative correlation between CVRR and log10-transformed (log) UAE (R=-0.3340, P <0.0001). CVRR showed a significant negative correlation with age, duration of diabetes, hemoglobin AIC, systolic blood pressure, diastolic blood pressure, and triglyceride level. Log UAE showed a significant positive correlation with body mass index, hemoglobin A1C, systolic blood pressure, diastolic blood pressure, total cholesterol, and triglyceride level. In the macroalbuminuric group (UAE above 300 mg/g creatinine; n=57), although CVRR showed a significant negative correlation with log UAE (R=-0.3571, P= 0.0064), but in normoalbuminuric (UAE below 30 mg/g Cr; n=79) and in microalbuminuric groups (30 to 300 mg/g Cr; n = 49), CVRR and log UAE showed no correlation.


CONCLUSIONS
Our data suggest that in type 2 diabetes, the association between CVRR and UAE is significant only in patients with macroalbuminuria.
Department of Medicine, Koshigaya Hospital, Dokkyo University School of Medicine, Koshigaya, Japan. takeb@gmail.plala.or.jp
Kohzo
K
Takebayashi
Rika
R
Matsutomo
Sachiko
S
Matsumoto
Mariko
M
Suetsugu
Sadao
S
Wakabayashi
Yoshimasa
Y
Aso
Toshihiko
T
Inukai
D000419:Albuminuria; D001786:Blood Glucose / Q000032:analysis; D001794:Blood Pressure / Q000502:physiology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000503:physiopathology* / Q000652:urine; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies
D001786:Blood Glucose; D006442:Glycated Hemoglobin; D008055:Lipids