Fig. 1Correlation between serum soluble dipeptidyl peptidase-4 (sDPP-4) levels and (A) serum creatinine or (B) estimated glomerular filtration rate (GFR) calculated by modification of diet in renal disease (MDRD) equation.
Table 1Baseline characteristics of whole study subjects
Characteristic |
Value |
Number |
140 |
Sex, male/female |
80/60 |
Age, yr |
62.1±8.2 |
Duration of diabetes, yr |
9.4±7.1 |
Smoking |
|
Non-smoker |
76 (54.3) |
Ex-smoker |
24 (17.1) |
Current smoker |
40 (28.6) |
BMI, kg/m2
|
25.3±3.0 |
Waist circumference, cm |
89.0±7.4 |
SBP, mm Hg |
132±16 |
DBP, mm Hg |
79±9 |
FBS, mg/dL |
139±34 |
HbA1c, % |
7.3±1.1 |
hs-CRP, mg/dL |
0.08 (0.04–0.19) |
Serum creatinine, mg/dL |
1.0±0.2 |
eGFR by MDRD, mL/min/1.73 m2
|
80.2±17.0 |
Microalbuminuria, mg/g creatinine |
14.8 (7.0–31.2) |
Total cholesterol, mg/dL |
181±31 |
Triglyceride, mg/dL |
147±79 |
HDL-C, mg/dL |
47±10 |
LDL-C, mg/dL |
109±27 |
sDPP-4 activity, ng/mL |
645±152 |
CAC scores, AU |
16.5 (0–128.8) |
Medications when enrolled |
|
Sulfonyureas |
97 (69.3) |
Metformin |
110 (78.6) |
Glitazone |
33 (23.6) |
Insulin |
15 (10.7) |
Statin |
29 (20.7) |
Antihypertensivesa
|
82 (58.6) |
Aspirin |
30 (21.4) |
Table 2Univariate correlation between soluble dipeptidyl peptidase-4 levels and clinical and biochemical variables
Variable |
Correlation coefficient |
P value |
Age |
0.012 |
0.898 |
BMI |
0.103 |
0.263 |
Waist circumference |
0.046 |
0.628 |
Duration of diabetes |
−0.051 |
0.579 |
SBP |
0.127 |
0.168 |
DBP |
0.129 |
0.162 |
HbA1c |
−0.124 |
0.178 |
hs-CRP |
−0.030 |
0.743 |
Serum creatinine |
−0.315 |
<0.001 |
eGFR by MDRD equation |
0.303 |
0.001 |
Urinary albumin-creatinine ratio |
−0.118 |
0.200 |
Total cholesterol |
0.214 |
0.019 |
LDL-C |
0.173 |
0.058 |
HDL-C |
0.074 |
0.423 |
Triglycerides |
0.044 |
0.637 |
Log (CACs+1) |
−0.121 |
0.186 |
Table 3Multiple linear regression analysis of variables influencing serum creatinine levels
|
Unstandardized coefficients |
Standardized coefficients |
P value |
B |
Standard error |
β |
Age |
0.003 |
0.002 |
0.129 |
0.060 |
Sex |
0.214 |
0.024 |
0.612 |
<0.001 |
BMI |
0.001 |
0.004 |
0.024 |
0.730 |
Duration of diabetes |
0.001 |
0.002 |
0.047 |
0.495 |
sDPP-4 |
0.000 |
0.000 |
−0.181 |
0.010 |
Table 4Multiple linear regression analysis of variables influencing estimated glomerular filtration rate by the MDRD equation (mL/min/1.73 m2)
|
Unstandardized coefficients |
Standardized coefficients |
P value |
B |
Standard error |
β |
Age |
−0.437 |
0.156 |
−0.184 |
0.006 |
Sex |
−20.821 |
2.289 |
−0.620 |
<0.001 |
BMI |
0.111 |
0.374 |
0.020 |
0.767 |
Duration of diabetes |
0.005 |
0.174 |
0.002 |
0.975 |
sDPP-4 |
0.018 |
0.007 |
0.167 |
0.014 |