Microalbuminuria, cardiovascular autonomic dysfunction, and insulin resistance in patients with type 2 diabetes mellitus.
Urinary albumin excretion/microalbuminuria and cardiovascular autonomic dysfunction are associated with high mortality in type 2 diabetic patients. We tested the hypothesis that the presence of microalbuminuria would correlate with cardiovascular autonomic dysfunction and insulin resistance in type 2 diabetic patients. The study group consisted of 15 Japanese patients with type 2 diabetes and microalbuminuria (age: 56 +/- 10 years, mean +/- SD). The control group consisted of 19 age-matched patients with normalbuminuria (56 +/- 7 years). Cardiovascular autonomic function was assessed by baroreflex sensitivity (BRS), heart rate variability, plasma norepinephrine concentration, and cardiac 123I-metaiodobenzylguanidine (MIBG) scintigraphy. BRS was lower in the microalbuminuria group than in the normalbuminuria group (P < .05). Early and delayed 123I-MIBG myocardial uptake values were lower (P < .05 and P < .005, respectively) and the percent washout rate of 123I-MIBG was higher (P < .0005) in the microalbuminuria group than in the normalbuminuria group. Fasting plasma glucose (P < .05) and insulin concentrations (P < .05), and the homeostasis model assessment (HOMA) index (P < .01) were higher in the microalbuminuria group than in the normalbuminuria group. Multiple regression analysis showed that urinary albumin excretion was independently predicted by the myocardial uptake of 123I-MIBG at delayed phase, fasting plasma insulin concentration, and the HOMA index. Our results indicate that the presence of microalbuminuria in our Japanese patients with type 2 diabetes is characterized by depressed cardiovascular autonomic function and insulin resistance, and that the myocardial uptake of 123I-MIBG at delayed phase, fasting plasma insulin, and HOMA index are independent predictors of urinary albumin excretion.
Takahashi
Naohiko
N
Department of Internal Medicine I, Oita University, Idaigaoka, Hasama, Japan.
Anan
Futoshi
F
Nakagawa
Mikiko
M
Yufu
Kunio
K
Ooie
Tatsuhiko
T
Nawata
Tomoko
T
Shigematsu
Sakuji
S
Hara
Masahide
M
Saikawa
Tetsunori
T
Yoshimatsu
Hironobu
H
D019797:3-Iodobenzylguanidine; D000368:Aged; D000375:Aging / Q000097:blood; D000419:Albuminuria / Q000209:etiology / Q000503:physiopathology*; D001342:Autonomic Nervous System Diseases / Q000209:etiology / Q000503:physiopathology*; D017704:Baroreflex / Q000502:physiology; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000209:etiology / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000503:physiopathology*; D004452:Echocardiography; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D007564:Japan; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood; D019275:Radiopharmaceuticals
D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine; D009638:Norepinephrine