Table 5. Logistic regression predicting likelihood of referral with all variables significant in the bivariate analysis
Model 1Model 2Model 3
OR (95% CI)P valueOR (95% CI)P valueOR (95% CI)P value
CKD severity
CKD status
 CKD_catG3bRef.Ref.Ref.
 CKD_catG41.23 (0.92 to 1.63)0.1621.30 (0.97 to 1.74)0.0811.30 (0.97 to 1.74)0.085
 CKD_catG51.02 (0.53 to 2.00)0.9430.99 (0.50 to 1.96)0.9770.98 (0.49 to 1.96)0.961
Albuminuria and proteinuria
 Normal to mildly increasedRef.Ref.Ref.
 Moderately increased0.82 (0.60 to 1.12)0.2010.89 (0.64 to 1.22)0.2430.87 (0.63 to 1.21)0.410
 Severely increased1.11 (0.81 to 1.51)0.5181.18 (0.86 to 1.62)0.3181.14 (0.83 to 1.58)0.417
Sociodemographics
Age group, years
 65–69Ref.Ref.
 70–740.75 (0.51 to 1.13)0.1680.77 (0.52 to 1.16)0.208
 75–790.97 (0.66 to 1.41)0.8561.01 (0.69 to 1.48)0.962
 80–840.43 (0.28 to 0.67)<0.001a 0.47 (0.30 to 0.73)<0.001a
 85–890.49 (0.30 to 0.79)0.003b 0.56 (0.34 to 0.91)0.020c
 ≥900.41 (0.20 to 0.84)0.015c 0.48 (0.23 to 0.99)0.046c
Ethnic group
 ChineseRef.Ref.
 Indian2.18 (1.23 to 3.86)0.008b 2.07 (1.16 to 3.70)0.014c
 Malay1.23 (0.88 to 1.70)0.2231.21 (0.87 to 1.68)0.268
 Others2.74 (1.32 to 5.70)0.007b 2.82 (1.35 to 5.89)0.006b
Medication
Fibrates1.69 (1.00 to 2.83)0.049
Statins1.35 (0.91 to 2.00)0.141
Insulin1.01 (0.72 to 1.43)0.935
Sulfonylureas1.15 (0.85 to 1.54)0.365
DPP41.20 (0.85 to 1.71)0.295
Antiplatelets1.23 (0.94 to 1.60)0.131
  • Results indicate the odds of being referred. a P<0.001; b P<0.01; c P<0.05. CKD = chronic kidney disease. DPP4 = dipeptidyl-peptidase 4 inhibitors.