Figures (3)  Tables (2)

    • Figure 1. 

      Illustration of the whole study design.

    • Figure 2. 

      Flowchart to show the development and validation of the VTDR prediction models. Abbreviations: HBP, hypertension; NDPH, Nanhai District People's Hospital; GDPH, Guangdong Provincial People's Hospital; MLR, multivariate logistic regression; LASSO, least absolute shrinkage and selection operator; ROC, receiver operating characteristic; AUC, area under the ROC curve; DCA, decision curve analysis.

    • Figure 3. 

      Nomograms were established to predict VTDR in patients with T2DM. Nomograms of (a) Model 1, (b) Model 2, (c) Model 3, and (d) Model 4 are from the development cohort. 'Points' refers to points for the individual variable and adds to the 'Total points'. 'VTDR risk of T2DM' was calculated according to the 'Total points'. ROC curves of the nomograms of Models 1, 2, 3, and 4 are derived from (e) development and (h) validation cohorts. The x-axis represents the false positive rate of the risk prediction. The y-axis represents the true positive rate of the risk prediction. Calibration curves of the nomograms generated from (f) development and (i) validation cohorts. The ordinate represents the actual probability of VTDR, while the abscissa represents the nomogram-predicted probability of VTDR. The diagonal dashed line means that the predicted probability is equal to the actual probability, and the greater the deviation from the diagonal, the greater the error of prediction. Decision curve analysis for nomograms established in (g) development and (j) validation cohorts. The abscissa shows the threshold probability, while the ordinate shows the net benefit. The gray line represents the assumption of all VTDR-positive cases, and the black line represents the assumption of all VTDR-negative cases.

    • Variables Development cohort Validation cohort
      No VTDR (n = 1,559) Yes VTDR (n = 74) p value No VTDR (n = 1,100) Yes VTDR (n = 177) p value
      Sex (n, %) 0.344 1.000
      Male 871 (55.9%) 46 (62.2%) 666 (60.5%) 107 (60.5%)
      Female 688 (44.1%) 28 (37.8%) 434 (39.5%) 70 (39.5%)
      Age (years) 57.0 [48.0, 64.5] 56.5 [45.8, 63.8] 0.670 56.0 [48.0, 65.0] 57.0 [50.0, 64.0] 0.647
      Diabetes duration (years) 3.33 [0.00, 9.50] 8.62 [1.44, 13.0] < 0.001 5.88 [0.50, 11.4] 10.2 [6.67, 17.0] < 0.001
      SBP (mm Hg) 126 [120, 138] 132 [121, 145] 0.021 129 [117, 141] 141 [125, 153] < 0.001
      DBP (mm Hg) 78 [72.0, 83] 79 [72, 86] 0.066 76 [68, 84] 78 [71, 87] 0.004
      FBG (mmol/L) 8.01 [6.24, 10.70] 9.47 [7.02, 12.60] 0.009 7.44 [5.81, 9.45] 8.17 [5.95, 10.7] 0.063
      PG-2h (mmol/L) 14.5 [11.4, 18.0] 14.4 [10.7, 17.0] 0.529 12.2 [8.93, 15.4] 11.0 [8.52, 15.5] 0.106
      Scr (μmol/L) 65.0 [53.0, 79.0] 66.5 [57.2, 106] 0.028 70.6 [57.8, 84.6] 81.0 [65.4, 123] < 0.001
      eGFR (mL/min/1.73 m2) 101 [77.9, 130] 87.4 [67.5, 110] 0.009 96.5 [78.3, 108] 83.6 [52.5, 100] < 0.001
      UA (μmol/L) 368 [298, 452] 402 [342, 481] 0.006 365 [296, 434] 387 [326, 467] 0.001
      TG (mmol/L) 1.63 [1.06, 2.65] 1.54 [1.06, 2.58] 0.65 1.54 [1.09, 2.26] 1.41 [0.97, 2.31] 0.223
      TC (mmol/L) 4.99 [4.20, 5.80] 4.80 [4.17, 5.81] 0.646 4.89 [4.06, 5.70] 5.00 [4.20, 6.30] 0.008
      HDLc (mmol/L) 1.23 [1.05, 1.46] 1.23 [1.02, 1.51] 0.895 0.99 [0.85, 1.15] 1.02 [0.88, 1.28] 0.05
      LDLc (mmol/L) 2.75 [2.06, 3.46] 2.74 [1.99, 3.42] 0.749 3.20 [2.59, 3.81] 3.40 [2.75, 4.18] 0.022
      RBC (1012/L) 4.76 [4.38, 5.23] 4.54 [4.21, 4.91] 0.002 4.66 [4.27, 5.04] 4.29 [3.86, 4.75] < 0.001
      WBC (109/L) 7.16 [5.97, 8.49] 7.46 [6.53, 8.85] 0.052 7.05 [5.92, 8.38] 7.47 [6.17, 8.71] 0.064
      PLT (109/L) 247 [208, 290] 242 [206, 297] 0.949 236 [197, 281] 232 [185, 301] 0.721
      HCT (%) 41.7 [38.6, 44.9] 39.3 [35.9, 42.8] < 0.001 40.6 [38.0, 43.0] 36.0 [32.0, 41.0] < 0.001
      Hb (g/L) 138 [126, 150] 131 [118, 145] < 0.001 136 [126, 147] 122 [109, 137] < 0.001
      HbA1c (%) 8.80 [6.90, 11.3] 10.80 [8.83, 12.20] < 0.001 9.50 [7.70, 11.3] 9.80 [8.20, 11.5] 0.03
      UACR (mg/g) < 0.001 < 0.001
      < 30 1,193 (76.5%) 25 (33.8%) 834 (75.8%) 61 (34.5%)
      30−300 309 (19.8%) 23 (31.1%) 190 (17.3%) 44 (24.9%)
      ≥ 300 57 (3.66%) 26 (35.1%) 76 (6.91%) 72 (40.7%)
      BMI (kg/m2) 0.254 0.126
      < 24 629 (40.3%) 37 (50.0%) 448 (40.7%) 85 (48.0%)
      24−28 618 (39.6%) 25 (33.8%) 443 (40.3%) 67 (37.9%)
      ≥ 28 312 (20.0%) 12 (16.2%) 209 (19.0%) 25 (14.1%)
      CVD 0.269 0.955
      No 1,482 (95.1%) 68 (91.9%) 958 (87.1%) 155 (87.6%)
      Yes 77 (4.94%) 6 (8.11%) 142 (12.9%) 22 (12.4%)
      Hypertension 0.972 < 0.001
      No 976 (62.6%) 47 (63.5%) 647 (58.8%) 77 (43.5%)
      Yes 583 (37.4%) 27 (36.5%) 453 (41.2%) 100 (56.5%)
      Hypoglycemic therapy < 0.001 < 0.001
      No 76 (4.87%) 1 (1.35%) 351 (31.9%) 24 (13.6%)
      Oral drugs 943 (60.5%) 22 (29.7%) 421 (38.3%) 77 (43.5%)
      Insulin 79 (5.07%) 4 (5.41%) 71 (6.45%) 17 (9.60%)
      Oral drugs and insulin 461 (29.6%) 47 (63.5%) 257 (23.4%) 59 (33.3%)
      Continuous variables are presented as median [interquartile range], and categorical variables as frequency (percentage). p-values < 0.05 were considered statistically significant, indicating a significant difference between the No-VTDR and Yes-VTDR groups. Bold values represent key outcome-related indicators.

      Table 1. 

      Clinical characteristics of the development and validation cohorts.

    • Variables Univariate analysis Multivariate analysis
      OR (95% CI) p value OR (95% CI) p value
      Sex (n, %) Male Reference
      Female 0.77 (0.48–1.25) 0.291
      Age (years) 1.00 (0.98–1.02) 0.642
      Diabetes duration (years) 1.07 (1.04–1.10) < 0.001 1.04 (1.00–1.08) 0.051#
      SBP (mm Hg) 1.03 (1.01–1.04) < 0.001 1.02 (1.00–1.03) 0.091#
      DBP (mm Hg) 1.03 (1.00–1.05) 0.042
      FBG (mmol/L) 1.04 (0.99–1.08) 0.103
      PG-2h (mmol/L) 0.98 (0.93–1.03) 0.392
      Scr (μmol/L) 1.00 (1.00–1.00) 0.233
      eGFR (mL/min/1.73 m2) 0.99 (0.99–1.00) 0.042 1.01 (1.00–1.01) 0.072#
      UA (μmol/L) 1.00 (1.00–1.00) 0.030 1.00 (1.00–1.00) 0.091#
      TG (mmol/L) 0.96 (0.87–1.07) 0.492
      TC (mmol/L) 1.01 (0.85–1.21) 0.890
      HDLc (mmol/L) 0.96 (0.58–1.61) 0.880
      LDLc (mmol/L) 1.03 (0.84–1.26) 0.790
      RBC (1012/L) 0.57 (0.40–0.82) < 0.001
      WBC (109/L) 1.00 (0.98–1.02) 0.942
      PLT (109/L) 1.00 (1.00–1.00) 0.673
      HCT (%) 0.90 (0.86–0.94) < 0.001 0.94 (0.89–0.99) 0.020#, *
      Hb (g/L) 0.98 (0.97–0.99) < 0.001
      HbA1c (%) 1.16 (1.07–1.26) < 0.001 1.16 (1.05–1.28) < 0.001#, *
      BMI (kg/m²) 0.98 (0.92–1.04) 0.542
      UACR (mg/g) < 30
      30−300 3.55 (1.99–6.34) < 0.001 2.81 (1.53–5.15) < 0.001#, *
      ≥ 300 21.77 (11.83–40.04) < 0.001 11.69 (5.67–24.09) < 0.001#, *
      CVD No Reference
      Yes 1.70 (0.71–4.04) 0.231
      Hypertension No Reference
      Yes 0.96 (0.59–1.56) 0.873
      Hypoglycemic therapy No Reference Reference
      Oral drugs 1.77 (0.24–13.32) 0.582 2.59 (0.29–22.88) 0.392
      Insulin 3.85 (0.42–35.18) 0.231 3.75 (0.34–40.95) 0.281
      Oral drugs and insulin 7.75 (1.06–56.87) 0.043 7.83 (0.92–66.61) 0.062#
      # represents variables with p < 0.10 in the MRL that were used to construct Model 1, including duration, SBP, eGFR, UA, HCT, HbA1c, UACR, and hypoglycemic therapy. * represents variables with p < 0.05 in the MRL that were used to construct Model 2, including duration, HCT, HbA1c, and UA. Bold values indicate key outcome-related indicators.

      Table 2. 

      Univariate and multivariable logistic regression analyses for risk of VTDR in the development cohort.