Fig. 1Differences in the proportions of the subjects with (A) prediabetes and (B) diabetes among the five groups classified according to serum cystatin C levels. Serum cystatin C groups: first (<0.8 mg/L), second (0.8 mg/L), third (0.9 mg/L), fourth (1.0 mg/L), and fifth (>1.0 mg/L). aP values were calculated using the chi-square test.
Fig. 2Correlations between serum cystatin C and HbA1c levels. (A) Total, (B) men, and (C) women.
Table 1The characteristics of the subjects with normal glucose, prediabetes, and diabetes defined by HbA1c levels
Parameter |
Normal glucose (A1c <5.7%) |
Prediabetes (5.7%≤A1c<6.5%) |
Diabetes (A1c ≥6.5%) |
P value |
Number |
1109 |
339 |
111 |
|
Male sex, n (%) |
648 (58.4) |
210 (61.9) |
79 (71.2) |
|
Age, yr |
50.1±8.9a
|
54.8±7.7b
|
57.5±7.6c
|
<0.001 |
WC, cm |
83.3±8.8a
|
87.7±9.4b
|
89.3±7.6b
|
<0.001 |
BMI, kg/m2
|
23.5±2.9a
|
24.9±3.4b
|
25.2±2.9b
|
<0.001 |
SBP, mm Hg |
115.9±13.2a
|
119.7±12.7b
|
121.6±13.4b
|
<0.001 |
DBP, mm Hg |
76.6±10.3a
|
78.9±9.4b
|
78.9±8.9b
|
<0.001 |
HbA1c, % |
5.2±0.2a
|
5.9±0.2b
|
7.7±1.4c
|
<0.001 |
FBG, mg/dL |
90.8±9.4a
|
102.8±15.0b
|
150.8±46.8c
|
<0.001 |
Insulin, µU/mL |
4.43±2.55a
|
5.64±3.79b
|
6.40±4.87c
|
<0.001 |
HOMA-IR |
1.01±0.63a
|
1.45±1.03b
|
2.31±1.82c
|
<0.001 |
TC, mg/dL |
214.0±35.7a
|
218.5±40.8b
|
199.4±44.6b
|
<0.001 |
LDL-C, mg/dL |
131.3±32.7a
|
135.2±38.2b
|
121.4±38.5b
|
0.001 |
TG, mg/dL (median) |
120.5±84.9 (99.0)a
|
150.9±104.7 (129.0)b
|
157.4±98.0 (136.0)b
|
<0.001d
|
HDL-C, mg/dL |
55.1±13.4a
|
53.6±13.8b
|
48.2±12.0b
|
<0.001 |
AST, IU/L |
27.6±9.9a
|
30.5±12.7b
|
32.0±15.0b
|
<0.001 |
ALT, IU/L |
24.7±14.3a
|
29.9±18.4b
|
34.5±20.9c
|
<0.001 |
GGT, IU/L (median) |
43.6±51.1 (27.0)a
|
50.8±57.8 (32.0)b
|
51.2±46.5 (34.0)b
|
<0.001d
|
BUN, mg/dL |
13.5±3.4a
|
14.4±3.5b
|
14.6±3.5b
|
<0.001 |
Creatinine, mg/dL |
0.85±0.16 |
0.86±0.16 |
0.86±0.16 |
0.641 |
Uric acid, mg/dL |
5.7±1.5a
|
5.9±1.5b
|
5.3±1.5b
|
0.001 |
hs-CRP, mg/dL (median) |
0.13±0.30 (0.06)a
|
0.16±0.28 (0.08)b
|
0.20±0.30 (0.10)c
|
<0.001d
|
Cystatin C, mg/L |
0.88±0.13a
|
0.91±0.14b
|
0.91±0.17b
|
0.001 |
Table 2Differences in the parameter values among the five groups classified according to the range of serum cystatin C levels
Parameter |
Cystatin C levelf
|
P value |
First |
Second |
Third |
Fourth |
Fifth |
Number |
226 |
413 |
429 |
292 |
199 |
|
Male sex, n (%) |
70 (30.9) |
217 (52.5) |
274 (63.9) |
219 (75.0) |
157 (78.9) |
|
Age, yr |
48.1±9.0a
|
49.4±8.8a
|
52.0±8.7b
|
53.9±8.2c
|
56.3±7.7d
|
<0.001 |
WC, cm |
79.8±8.2a
|
83.6±8.9b
|
85.1±8.9c
|
87.2±8.7d
|
88.2±9.2d
|
<0.001 |
BMI, kg/m2
|
22.7±2.6a
|
23.7±2.9b
|
24.0±2.9b
|
24.7±3.3c
|
24.8±3.2c
|
<0.001 |
SBP, mm Hg |
113.1±12.7a
|
115.5±12.9b
|
117.6±13.5c
|
119.6±12.5c,d
|
120.7±13.1d
|
<0.001 |
DBP, mm Hg |
73.5±10.2a
|
76.2±9.9b
|
77.8±10.1b,c
|
79.0±9.8c,d
|
80.3±9.2d
|
<0.001 |
HbA1c, % |
5.5±1.0 |
5.4±0.6 |
5.5±0.8 |
5.5±0.7 |
5.6±0.7 |
0.141 |
FBG, mg/dL |
96.3±30.1 |
95.8±18.3 |
98.2±23.3 |
99.4±20.7 |
99.6±20.9 |
0.125 |
Insulin, µU/mL |
4.35±2.63a
|
4.73±2.86a
|
4.81±3.10a,b
|
4.99±3.23a,b
|
5.44±3.95b
|
0.007 |
HOMA-IR |
1.06±0.80a
|
1.14±0.80a
|
1.20±1.02a,b
|
1.24±0.87a,b
|
1.38±1.18b
|
0.005 |
TC, mg/dL |
202.5±35.0a
|
213.4±37.8b
|
215.3±38.9b
|
217.1±36.9b
|
220.6±37.4b
|
<0.001 |
LDL-C, mg/dL |
120.0±32.6a
|
130.5±35.3b
|
132.0±35.1b
|
135.8±33.0b,c
|
139.1±33.2c
|
<0.001 |
TG, mg/dL (median) |
98.4±85.7 (72.0)a
|
122.6±86.2 (99.0)b
|
133.0±92.7 (105.0)b
|
140.8±91.1 (116.5)c
|
156.9±96.7 (133.0)c
|
<0.001g
|
HDL-C, mg/dL |
59.4±13.3a
|
56.3±13.0a
|
54.1±14.1b
|
50.9±12.6b
|
49.6±12.2c
|
<0.001 |
AST, IU/L |
24.2±8.2a
|
26.8±10.7b
|
29.2±11.4c
|
30.3±11.7c
|
32.9±11.3d
|
<0.001 |
ALT, IU/L |
20.7±12.5a
|
24.6±15.2b
|
27.6 ± 15.7c
|
28.0±16.4c
|
32.5±19.0d
|
<0.001 |
GGT, IU/L (median) |
30.8±31.2 (20.0)a
|
42.0±45.4 (27.0)b
|
46.7±51.9 (30.0)b,c
|
51.8±59.5 (35.0)c,d
|
59.3±68.3 (36.0)d
|
<0.001g
|
BUN, mg/dL |
13.0±3.4a
|
13.3±3.3a
|
13.9±3.6b
|
14.1±3.4b
|
14.8±3.4c
|
<0.001 |
Creatinine, mg/dL |
0.72±0.13a
|
0.81±0.14b
|
0.87±0.14c
|
0.92±0.14d
|
0.98±0.14e
|
<0.001 |
Uric acid, mg/dL |
4.7±1.2a
|
5.5±1.3b
|
5.7±1.4c
|
6.1±1.4d
|
6.7±1.7e
|
<0.001 |
hs-CRP, mg/dL (median) |
0.07±0.12 (0.045)a
|
0.13±0.35 (0.060)b
|
0.13±0.23 (0.070)b,c
|
0.17±0.30 (0.090)d
|
0.21±0.41 (0.100)d
|
<0.001g
|
Table 3OR (95% CI) for the prevalence of diabetic conditions
Cystatin Ca
|
ORb (95% CI) |
P value |
ORc (95% CI) |
P value |
ORd (95% CI) |
P value |
Total |
|
|
|
|
|
|
First |
1 (reference) |
|
1 (reference) |
|
1 (reference) |
|
Second |
1.26 (0.86–1.84) |
0.232 |
1.06 (0.71–1.59) |
0.756 |
1.01 (0.65–1.49) |
0.940 |
Third |
1.44 (0.99–2.09) |
0.055 |
0.99 (0.66–1.48) |
0.963 |
0.89 (0.58–1.35) |
0.588 |
Fourth |
1.29 (0.86–1.94) |
0.210 |
0.75 (0.48–1.17) |
0.215 |
0.61 (0.39–0.97) |
0.037 |
Fifth |
2.35 (1.54–3.58) |
<0.001 |
1.21 (0.76–1.92) |
0.420 |
1.01 (0.62–1.63) |
0.964 |
Men |
|
|
|
|
|
|
First |
1 (reference) |
|
1 (reference) |
|
1 (reference) |
|
Second |
0.75 (0.42–1.33) |
0.329 |
0.92 (0.50–1.69) |
0.802 |
0.84 (0.46–1.54) |
0.584 |
Third |
0.75 (0.43–1.31) |
0.321 |
0.56 (0.31–1.01) |
0.055 |
0.67 (0.37–1.21) |
0.187 |
Fourth |
0.63 (0.35–1.12) |
0.119 |
0.72 (0.41–1.28) |
0.268 |
0.48 (0.26–0.88) |
0.019 |
Fifth |
1.17 (0.65–2.10) |
0.589 |
0.88 (0.49–1.58) |
0.675 |
0.81 (0.43–1.52) |
0.522 |
Women |
|
|
|
|
|
|
First |
1 (reference) |
|
1 (reference) |
|
1 (reference) |
|
Second |
1.57 (0.92–2.68) |
0.094 |
1.11 (0.63–1.96) |
0.698 |
1.07 (0.60–1.91) |
0.813 |
Third |
2.11 (1.22–3.63) |
0.007 |
1.30 (0.72–2.32) |
0.374 |
1.18 (0.65–2.16) |
0.572 |
Fourth |
2.30 (1.20–4.40) |
0.012 |
0.91 (0.45–1.87) |
0.817 |
0.76 (0.36–1.59) |
0.475 |
Fifth |
4.13 (1.97–8.65) |
<0.001 |
1.32 (0.58–3.00) |
0.507 |
1.10 (0.47–2.57) |
0.824 |