Background
Methods
Study subjects
Measurements
Statistical analysis
Results
Clinical and biochemical characteristics of subjects
I (11.2–12.6%) | II (12.7–13.1%) | III(13.2–21.0%) | χ2 | P | |
---|---|---|---|---|---|
n | 181 | 190 | 188 | ||
RDW | 12.3 (12.2–12.5)*# | 13 (12.8–13.1)★# | 13.6 (13.3–14.2)★* | 497.518 | < 0.001 |
male(%) | 130 (71.8)# | 115 (60.5) | 98 (52.1)★ | 15.172 | 0.001 |
age (years) | 52 (44–60)*# | 56 (47–65)★# | 61 (51–69)★* | 34.804 | < 0.001 |
duration (years) | 6 (1–10) | 5 (1–10)# | 7.5 (3–12.5)* | 13.103 | 0.001 |
BMI (kg/m2) | 25.65 (23.83–27.58) | 25.82 (23.45–28.03) | 25.33 (22.84–27.51) | 1.590 | 0.452 |
SBP (mmHg) | 130 (120–140) | 127.5 (118–140) | 130 (118–144) | 2.741 | 0.254 |
DBP (mmHg) | 80 (74–88)# | 79 (70–86) | 79 (70–85.5)★ | 8.369 | 0.015 |
AST (mmol/L) | 18 (14–23) | 20 (15–23) | 19 (16–23) | 4.731 | 0.094 |
TG (mmol/L) | 1.84 (1.29–2.88)# | 1.66 (1.09–2.67) | 1.37 (0.99–2.33)★ | 15.902 | < 0.001 |
TCH (mmol/L) | 4.5 (3.92–5.11) | 4.58 (3.89–5.15) | 4.39 (3.81–5.09) | 2.430 | 0.297 |
LDL (mmol/L) | 2.82 (2.35–3.29) | 2.86 (2.47–3.33) | 2.87 (2.43–3.18) | 2.091 | 0.352 |
HDL (mmol/L) | 0.94 (0.76–1.09) | 0.98 (0.79–1.13) | 0.99 (0.82–1.22) | 3.429 | 0.180 |
ALT (mmol/L) | 21 (14–30) | 21 (15–29) | 19 (13.5–28) | 2.148 | 0.342 |
Cr (umol/L) | 79 (63–91) | 79 (63–91) | 79 (65–93) | 0.495 | 0.781 |
SUA (umol/L) | 286 (249–360) | 295 (236–353) | 291 (237.5–364) | 0.150 | 0.928 |
FBG (mmol/L) | 8.88 (7.18–10.65)# | 8.02 (6.67–10.44) | 7.65 (6.14–9.53)★ | 12.001 | 0.002 |
P2hBG (mmol/L) | 18.1 (15.02–20.34) | 17.9 (14.39–21.17) | 16.94 (14.32–20.17) | 3.462 | 0.177 |
HbA1c (%) | 9.4 (7.8–10.7)# | 8.8 (7.6–11.3)# | 8.3 (6.8–10)★* | 11.338 | 0.003 |
FCP (nmol/L) | 0.73 (0.56–0.96) | 0.71 (0.55–0.97) | 0.71 (0.51–0.96) | 0.301 | 0.860 |
P2hCP (nmol/L) | 1.69 (1.18–2.1) | 1.68 (1.25–2.25) | 1.73 (1.24–2.44) | 0.685 | 0.710 |
hypertension(%) | 68 (37.6) | 62 (32.6) | 75 (39.9) | 2.238 | 0.327 |
poor glycemic control(%) | 180 (99.4) | 185 (97.4) | 185 (98.4) | 2.407 | 0.314 |
hyperuricemia(%) | 23 (12.7) | 26 (13.7) | 30 (16.0) | 0.850 | 0.654 |
Islet function indexes | |||||
FCPI | 0.08 (0.06–0.12) | 0.09 (0.06–0.12) | 0.09 (0.06–0.12) | 1.867 | 0.393 |
PPCPI | 0.09 (0.07–0.14) | 0.09 (0.06–0.15) | 0.1 (0.07–0.15) | 1.378 | 0.502 |
ΔC-peptide | 0.91 (0.53–1.29) | 0.91 (0.57–1.42) | 0.96 (0.6–1.41) | 1.592 | 0.451 |
HOMA2%B | 47.1 (32.9–75.4)# | 54.05 (34.1–81) | 57.9 (38.65–95.4)★ | 6.670 | 0.036 |
HOMA2IR | 1.9 (1.45–2.45) | 1.92 (1.41–2.48) | 1.81 (1.33–2.5) | 1.244 | 0.537 |
Clinical and biochemical characteristics of the patients in different gender subgroups
male(n = 343) | female(n = 216) | Z/χ2 | P | |
---|---|---|---|---|
RDW | 12.9 (12.4–13.2) | 13.1 (12.7–13.6) | 17.601 | < 0.001 |
age (years) | 52 (44–62) | 61 (53–68) | 52.961 | < 0.001 |
duration (years) | 6 (1–10) | 6 (2–10) | 2.252 | 0.133 |
BMI (kg/m2) | 25.73 (23.66–27.92) | 25.29 (22.88–27.55) | 1.608 | 0.205 |
SBP (mmHg) | 130 (118–140) | 130 (119.5–140) | 0.739 | 0.390 |
DBP (mmHg) | 80 (74–88) | 76 (70–82) | 21.217 | < 0.001 |
AST (mmol/L) | 19 (15–24) | 19 (15–23) | 0.027 | 0.869 |
TG (mmol/L) | 1.69 (1.12–2.79) | 1.57 (1.02–2.29) | 4.808 | 0.028 |
TCH (mmol/L) | 4.5 (3.85–5.06) | 4.44 (3.97–5.14) | 0.197 | 0.657 |
LDL (mmol/L) | 2.86 (2.39–3.23) | 2.86 (2.44–3.27) | 1.033 | 0.309 |
HDL (mmol/L) | 0.94 (0.77–1.1) | 1.02 (0.87–1.23) | 14.639 | < 0.001 |
ALT (mmol/L) | 22 (15–33) | 18 (13–27) | 9.213 | 0.002 |
Cr (umol/L) | 83 (72–97) | 68 (55–82) | 75.969 | < 0.001 |
SUA (umol/L) | 313 (265–378) | 261 (221–305) | 52.574 | < 0.001 |
FBG (mmol/L) | 8.27 (6.56–10.56) | 8.21 (6.44–10.25) | 0.158 | 0.691 |
P2hBG (mmol/L) | 17.21 (14.67–20.18) | 17.95 (14.5–20.95) | 1.631 | 0.202 |
HbA1c (%) | 8.8 (7.3–10.7) | 8.6 (7.3–10.7) | 0.136 | 0.712 |
FCP (nmol/L) | 0.71 (0.55–0.99) | 0.7 (0.52–0.93) | 0.860 | 0.354 |
P2hCP (nmol/L) | 1.68 (1.22–2.22) | 1.77 (1.26–2.25) | 0.325 | 0.569 |
hypertension(%) | 128 (37.3) | 77 (35.6) | 0.159 | 0.690 |
poor glycemic control(%) | 338 (98.5) | 212 (98.1) | fisher’s | 0.740 |
hyperuricemia(%) | 48 (14) | 31 (14.4) | 0.014 | 0.906 |
Islet function indexes | ||||
FCPI | 0.09 (0.06–0.12) | 0.08 (0.06–0.12) | 0.236 | 0.627 |
PPCPI | 0.1 (0.07–0.14) | 0.09 (0.07–0.16) | 0.014 | 0.907 |
ΔC-peptide | 0.92 (0.54–1.35) | 0.97 (0.61–1.4) | 1.187 | 0.276 |
HOMA2%B | 51.2 (35.5–82.5) | 52.95 (33.2–83.1) | 0.003 | 0.957 |
HOMA2IR | 1.9 (1.41–2.57) | 1.84 (1.36–2.44) | 0.998 | 0.318 |
I (11.2–12.6%) | II (12.7–13.1%) | III(13.2–21.0%) | χ2 | P | |
---|---|---|---|---|---|
n | 130 | 115 | 98 | ||
RDW | 12.3 (12.2–12.5)*# | 13 (12.8–13.1)★# | 13.6 (13.3–14.1)★* | 303.536 | < 0.001 |
age (years) | 49 (40–59)# | 52 (43–63) | 55 (49–65)★ | 16.594 | < 0.001 |
duration (years) | 7 (1–10) | 4 (0.3–10)# | 7 (2–10)* | 8.893 | 0.012 |
BMI (kg/m2) | 26.07 (24.03–28.04)# | 26.17 (23.7–28.34) | 25.16 (22.34–26.93)★ | 7.548 | 0.023 |
SBP (mmHg) | 130 (120–140) | 126 (117–139) | 130 (116–140) | 1.612 | 0.447 |
DBP (mmHg) | 80 (76–90) | 80 (74–86) | 80 (71–88) | 3.389 | 0.184 |
AST (mmol/L) | 18 (14–24) | 19 (15–22) | 20 (17–23) | 4.945 | 0.084 |
TG (mmol/L) | 2 (1.31–3.21)# | 1.64 (1.15–2.89) | 1.32 (0.95–2.5)★ | 12.766 | 0.002 |
TCH (mmol/L) | 4.52 (3.91–5.16) | 4.52 (3.8–5.02) | 4.42 (3.78–5.1) | 0.426 | 0.808 |
LDL (mmol/L) | 2.82 (2.29–3.19) | 2.87 (2.43–3.29) | 2.88 (2.58–3.18) | 1.532 | 0.465 |
HDL (mmol/L) | 0.92 (0.74–1.02)# | 0.95 (0.77–1.1) | 0.98 (0.83–1.16)★ | 7.984 | 0.018 |
ALT (mmol/L) | 22 (15–34) | 20 (15–30) | 22 (15–33) | 0.836 | 0.658 |
Cr (umol/L) | 82.5 (70–94) | 85 (74–98) | 82.5 (73–97) | 1.535 | 0.464 |
SUA (umol/L) | 306 (260–370) | 306 (250–369) | 331 (270–387) | 2.539 | 0.281 |
FBG (mmol/L) | 8.82 (7.14–10.62) | 8.02 (6.63–10.44) | 7.6 (6.24–10.21) | 4.391 | 0.111 |
P2hBG (mmol/L) | 17.73 (15.02–20.18) | 17.31 (14.29–20.91) | 16.44 (14.19–19.65) | 2.351 | 0.309 |
HbA1c (%) | 9.1 (7.7–10.6) | 8.8 (7.7–11.2) | 8.3 (6.9–10.4) | 3.063 | 0.216 |
hypertension(%) | 52 (40.0) | 37 (32.2) | 39 (39.8) | 1.958 | 0.376 |
poor glycemic control(%) | 129 (99.2) | 113 (98.3) | 96 (98.0) | 0.950 | 0.741 |
hyperuricemia(%) | 17 (13.1) | 16 (13.9) | 15 (15.3) | 0.232 | 0.891 |
Islet function indexes | |||||
FCP (nmol/L) | 0.74 (0.58–1.03) | 0.71 (0.54–0.99) | 0.7 (0.54–0.97) | 0.923 | 0.630 |
P2hCP (nmol/L) | 1.7 (1.26–2.19) | 1.72 (1.22–2.28) | 1.65 (1.22–2.25) | 0.107 | 0.948 |
FCPI | 0.09 (0.06–0.12) | 0.09 (0.06–0.12) | 0.09 (0.07–0.12) | 0.102 | 0.950 |
PPCPI | 0.1 (0.07–0.14) | 0.09 (0.06–0.15) | 0.09 (0.07–0.15) | 0.210 | 0.900 |
ΔC-peptide | 0.91 (0.53–1.34) | 0.91 (0.53–1.45) | 0.93 (0.56–1.31) | 0.194 | 0.908 |
HOMA2%B | 49.65 (33.5–79.5) | 51.2 (34.5–84.1) | 57.9 (38.3–88.9) | 1.070 | 0.586 |
HOMA2IR | 1.92 (1.47–2.68) | 1.91 (1.33–2.51) | 1.8 (1.37–2.46) | 1.425 | 0.490 |
I (11.2–12.6%) | II (12.7–13.1%) | III(13.2–21.0%) | χ2 | P | |
---|---|---|---|---|---|
n | 51 | 79 | 90 | ||
RDW | 12.4 (12.2–12.5)*# | 13 (12.8–13.1)★# | 13.7 (13.4–14.3)★* | 188.296 | < 0.001 |
age (years) | 56 (51–62)# | 61 (54–66) | 64 (53–71)★ | 11.575 | 0.003 |
duration (years) | 6 (1–10) | 5 (2–10) | 8 (3–13) | 5.192 | 0.075 |
BMI (kg/m2) | 24.91 (22.41–26.45) | 25.48 (22.52–27.73) | 25.6 (23.61–28.2) | 3.530 | 0.171 |
SBP (mmHg) | 130 (120–140) | 129 (118–140) | 130 (118–146) | 1.345 | 0.511 |
DBP (mmHg) | 78 (70–86) | 76 (70–82) | 76 (70–81) | 2.030 | 0.362 |
AST (mmol/L) | 18 (14–22) | 21 (15–25) | 18.5 (15–23) | 4.334 | 0.115 |
TG (mmol/L) | 1.58 (1.15–2.5) | 1.67 (0.96–2.3) | 1.46 (1.01–2.13) | 1.712 | 0.425 |
TCH (mmol/L) | 4.36 (3.98–5.1) | 4.66 (4.08–5.71) | 4.35 (3.84–5.03) | 4.834 | 0.089 |
LDL (mmol/L) | 2.84 (2.46–3.32) | 2.86 (2.61–3.45) | 2.86 (2.35–3.18) | 1.954 | 0.376 |
HDL (mmol/L) | 1.07 (0.89–1.35) | 1.01 (0.87–1.17) | 1 (0.78–1.27) | 2.048 | 0.359 |
ALT (mmol/L) | 17 (14–26) | 21 (15–28)# | 17 (12–25)* | 6.930 | 0.031 |
Cr (umol/L) | 62 (55–73) | 65 (53–79) | 74 (58–85) | 6.754 | 0.034 |
SUA (umol/L) | 260 (221–281) | 280 (217–318) | 258.5 (221–302) | 1.328 | 0.515 |
FBG (mmol/L) | 9.36 (7.42–11.83)# | 8.03 (6.7–11.3) | 7.7 (5.69–9.28)★ | 9.464 | 0.009 |
P2hBG (mmol/L) | 18.59 (14.73–20.79) | 18.12 (14.39–21.53) | 17.49 (14.49–20.48) | 1.958 | 0.376 |
HbA1c (%) | 9.8 (8–11.2)# | 8.95 (7.6–11.6)# | 8.4 (6.8–9.8)★* | 10.045 | 0.007 |
hypertension(%) | 16 (31.4) | 25 (33.3) | 36 (40.0) | 1.325 | 0.516 |
poor glycemic control(%) | 51 (100.0) | 72 (96.0) | 89 (98.9) | 2.316 | 0.358 |
hyperuricemia(%) | 6 (11.8) | 10 (13.3) | 15 (16.7) | 0.733 | 0.693 |
Islet function indexes | |||||
FCP (nmol/L) | 0.7 (0.49–0.85) | 0.7 (0.56–0.92) | 0.71 (0.49–0.95) | 1.595 | 0.450 |
P2hCP (nmol/L) | 1.65 (1.1–1.98) | 1.67 (1.26–2.24) | 1.84 (1.32–2.51) | 2.714 | 0.257 |
FCPI | 0.07 (0.05–0.12) | 0.09 (0.06–0.12) | 0.1 (0.06–0.13) | 5.122 | 0.077 |
PPCPI | 0.08 (0.05–0.14) | 0.09 (0.07–0.16) | 0.1 (0.07–0.16) | 2.650 | 0.266 |
ΔC-peptide | 0.9 (0.55–1.22) | 0.91 (0.62–1.4) | 1.01 (0.66–1.5) | 2.816 | 0.245 |
HOMA%2B | 39.6 (28–66.2)# | 54.3 (31.7–79.7) | 58.0 (40.3–97.4)★ | 8.797 | 0.012 |
HOMA2IR | 1.85 (1.31–2.25) | 1.94 (1.44–2.45) | 1.81 (1.31–2.53) | 1.165 | 0.559 |
Correlation between RDW and various metabolic parameters in total and different gender subgroups
total | male | female | ||||
---|---|---|---|---|---|---|
r | P | r | P | r | P | |
age (years) | 0.250 | < 0.001 | 0.224 | < 0.001 | 0.188 | 0.006 |
duration (years) | 0.099 | 0.019 | 0.053 | 0.326 | 0.145 | 0.033 |
BMI (kg/m2) | −0.060 | 0.157 | −0.122 | 0.024 | 0.055 | 0.418 |
SBP (mmHg) | 0.015 | 0.719 | 0.002 | 0.977 | 0.016 | 0.811 |
DBP (mmHg) | −0.137 | 0.001 | − 0.121 | 0.025 | − 0.078 | 0.255 |
TG (mmol/L) | −0.136 | 0.001 | −0.150 | 0.005 | −0.065 | 0.344 |
TCH (mmol/L) | −0.046 | 0.277 | −0.042 | 0.441 | −0.065 | 0.343 |
LDL (mmol/L) | 0.025 | 0.554 | 0.039 | 0.469 | −0.012 | 0.863 |
HDL (mmol/L) | 0.082 | 0.052 | 0.150 | 0.005 | −0.089 | 0.193 |
AST (mmol/L) | 0.091 | 0.031 | 0.118 | 0.029 | 0.052 | 0.445 |
ALT (mmol/L) | −0.069 | 0.104 | −0.005 | 0.929 | −0.140 | 0.040 |
Cr (umol/L) | 0.026 | 0.544 | 0.047 | 0.385 | 0.157 | 0.021 |
SUA (umol/L) | −0.024 | 0.570 | 0.043 | 0.430 | 0.011 | 0.871 |
FBG (mmol/L) | −0.133 | 0.002 | −0.085 | 0.117 | −0.219 | 0.001 |
P2hBG (mmol/L) | −0.054 | 0.201 | −0.046 | 0.401 | −0.098 | 0.151 |
HbA1c (%) | −0.135 | 0.001 | −0.066 | 0.223 | −0.245 | < 0.001 |
FCP (nmol/L) | 0.013 | 0.754 | 0.001 | 0.990 | 0.042 | 0.543 |
P2hCP (nmol/L) | 0.048 | 0.260 | −0.001 | 0.984 | 0.112 | 0.100 |
FCPI | 0.074 | 0.080 | 0.037 | 0.496 | 0.134 | 0.049 |
PPCPI | 0.050 | 0.236 | 0.016 | 0.773 | 0.108 | 0.112 |
ΔC-peptide | 0.047 | 0.272 | −0.006 | 0.917 | 0.113 | 0.097 |
HOMA2%B | 0.110 | 0.009 | 0.056 | 0.297 | 0.196 | 0.004 |
HOMA2IR | −0.012 | 0.771 | −0.013 | 0.814 | 0.001 | 0.993 |
Multiple linear regression analysis of RDW and HOMA2%B, HOMA2IR or HbA1c
Partial regression coefficient (B) | Standard error (SE) | Standard partial regression coefficient (β) | t | P | ||
---|---|---|---|---|---|---|
Total | RDW (unadjusted) | 0.002 | 0.001 | 0.138 | 3.280 | 0.001 |
RDW (adjusted for model 1: age, BMI and diabetes duration) | 0.002 | 0.001 | 0.122 | 2.902 | 0.004 | |
RDW (adjusted for model 1: age, BMI, diabetes duration and HbA1c) | 0.002 | 0.001 | 0.097 | 2.096 | 0.037 | |
Male | RDW (unadjusted) | 0.003 | 0.001 | 0.159 | 2.970 | 0.003 |
RDW (adjusted for model 1: age, BMI and diabetes duration) | 0.003 | 0.001 | 0.158 | 3.044 | 0.003 | |
RDW (adjusted for model 1: age, BMI, diabetes duration and HbA1c) | 0.004 | 0.001 | 0.192 | 3.244 | 0.001 | |
Female | RDW (unadjusted) | 0.002 | 0.001 | 0.113 | 1.666 | 0.097 |
RDW (adjusted for model 1: age, BMI and diabetes duration) | 0.002 | 0.001 | 0.111 | 1.559 | 0.120 | |
RDW (adjusted for model 1: age, BMI, diabetes duration and HbA1c) | 0.0004 | 0.001 | 0.029 | 0.372 | 0.710 |
Partial regression coefficient (B) | Standard error (SE) | Standard partial regression coefficient (β) | t | P | ||
---|---|---|---|---|---|---|
Total | RDW (unadjusted) | −0.059 | 0.017 | −0.142 | −3.381 | 0.001 |
RDW (adjusted formodel 1: age, BMI and diabetes duration) | −0.041 | 0.018 | −0.100 | −2.349 | 0.019 | |
Male | RDW (unadjusted) | −0.030 | 0.020 | −0.082 | −1.507 | 0.133 |
RDW (adjusted formodel 1: age, BMI and diabetes duration) | −0.007 | 0.020 | −0.019 | −0.356 | 0.722 | |
Female | RDW (unadjusted) | −0.104 | 0.031 | −0.221 | −3.301 | 0.001 |
RDW (adjusted formodel 1: age, BMI and diabetes duration) | −0.099 | 0.032 | −0.212 | −3.095 | 0.002 |