Arterial stiffness and renal impairment in non-proteinuric type 2 diabetic patients.
Aims/Introduction:  Although increases in urinary protein excretion generally precede a decline in the glomerular filtration rate, non-proteinuric renal impairment is common in patients with diabetes. In the present study, we examined the relationship between indices of arterial stiffness and renal function in type 2 diabetic patients without proteinuria.


METHODS
Blood sampling, 24-h urine collection, brachial-ankle pulse wave velocity, and 24-h ambulatory blood pressure monitoring were performed in type 2 diabetic patients without overt proteinuria. The ambulatory arterial stiffness index was calculated as (1 - the regression slope of diastolic/systolic ambulatory blood pressure). Estimated glomerular filtration rate (eGFR)was calculated using the simplified prediction equation proposed by the Japanese Society of Nephrology.


RESULTS
Of 213 non-proteinuric patients with type 2 diabetes, 60 (28.2%) had a reduced eGFR (<60 mL/min per 1.73 m(2)). Although the urinary albumin excretion rate was significantly correlated with the eGFR, 34 of 152 patients with normoalbuminuria (22.4%) had a reduced eGFR. The eGFR was significantly and negatively correlated with the ambulatory arterial stiffness index and brachial-ankle pulse wave velocity, but not with 24-h pulse pressure. Multivariate analysis revealed that increased age and increased urinary albumin excretion were independently associated with decreased eGFR. In addition, the ambulatory arterial stiffness index, but not brachial-ankle pulse wave velocity, were found to be independently and significantly associated with eGFR.


CONCLUSIONS
Ambulatory arterial stiffness index is a marker for increased risk of renal failure in non-proteinuric patients with type 2 diabetes. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2011.00146.x, 2012).
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Keiko
K
Nakao
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Takashi
T
Uzu
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Shin-Ichi
S
Araki
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Shinji
S
Kume
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Naoko
N
Deji
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Masami
M
Chin-Kanasaki
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Hisazumi
H
Araki
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Keiji
K
Isshiki
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Toshiro
T
Sugimoto
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Hiromichi
H
Kawai
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Yoshihiko
Y
Nishio
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Atsunori
A
Kashiwagi
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Hiroshi
H
Maegawa
Albuminuria; Chronic kidney disease; Vascular compliance