Table 1 Characteristics of Type 2 diabetes patients with no diabetic retinopathy and mild non-proliferative DR at baseline (n = 4570)

Age (years), median (IQR)

61.0 (55.0–67.0)

60.0 (55.0–67.0)

0.295

Male gender, n (%)

2429 (54.6)

70 (57.9)

0.478

Diabetes duration (years), median (IQR)

6.0 (3.0–10.0)

8.0 (3.0–11.0)

0.037

Ethnicity, n (%)

0.843

 Chinese

3028 (68.1)

79 (65.3)

 Malay

971 (21.8)

29 (24.0)

 Indian

427 (9.6)

13 (10.7)

 Eurasian

23 (0.5)

0 (0.0)

Educational attainment, n (%)

0.722

 Primary or lower

1005 (22.6)

29 (24.0)

 Secondary or above

3443 (77.4)

92 (76.0)

Housing type, n (%)

0.085

 Public

3921 (88.3)

113 (93.4)

 Private

519 (11.7)

8 (6.6)

Monthly Household Income, n (%)

0.679

  < $2000

1164 (36.0)

34 (34.0)

 $2000 and above

2068 (64.0)

66 (66.0)

Occupation, n (%)

0.488

 Unemployed

155 (3.5)

7 (5.8)

 Housewife

499 (11.2)

13 (10.7)

 Retired

1113 (25.0)

26 (21.5)

 Working

2682 (60.3)

75 (62.0)

Marital status, n (%)

0.287

 Single or never married

564 (12.7)

14 (11.6)

 Married

3359 (75.5)

87 (71.9)

 Separated, divorced or widowed

526 (11.8)

20 (16.5)

Polyclinic Location, n (%)

0.129

 Bedok

1203 (27.0)

37(30.6)

 Bukit Merah

911 (20.5)

23 (19.0)

 Outram

1113 (25.0)

38 (31.4)

 Pasir Ris

1222(27.5)

23 (19.0)

 Lives alone (yes), n (%)

365 (8.2)

14 (11.6)

0.185

Smoking status, n (%)

0.335

 Never

3409 (76.6)

88 (72.7)

 Past

471 (10.6)

12 (9.9)

 Current

569 (12.8)

21 (17.4)

Alcohol use, n (%)

0.445

 Never

3390 (76.2)

96 (79.3)

 Past

315 (7.0)

5 (4.1)

 Current

744 (16.7)

20 (16.5)

BMI (kg/m2), median (IQR)

26.7 (24.1–30.2)

26.9 (24.1–30.5)

0.559

BMI categories (kg/m2)

0.898

  < 18.5

34 (0.8)

1 (0.8)

 18.5—23.0

657 (14.9)

16 (13.2)

 23.0—27.5

1814 (41.0)

49 (40.5)

  ≥ 27.5

1919 (43.4)

55 (45.4)

Blood pressure (mmHg), median (IQR)

 Systolic

130.0 (121.5–138.0)

133.0 (124–139.0)

0.054

 Diastolic

70.0 (64.5–77.0)

69.0 (64.0–77.0)

0.309

 Hypertension^b, n (%)

3520 (79.1)

101 (83.5)

0.244

 Dyslipidaemia^c, n (%)

4128 (92.8)

111 (91.7)

0.660

History of cardiovascular disease, n (%)

 Coronary artery disease (yes)

506 (11.4)

18 (14.9)

0.242

 Stroke

179 (4.0)

10 (8.3)

0.021

 Kidney disease, n (%)

620 (14.0)

19 (15.7)

0.580

Diabetes treatment, n (%)

 Insulin

288 (6.5)

11 (9.1)

0.251

 Oral anti-diabetic medications

3395 (76.3)

105 (86.8)

0.007

PVA (Better eye)

0.683

 None (LogMAR ≤ 0.3)

4228 (95.1)

116 (95.9)

 Mild (LogMAR > 0.3)

220 (4.9)

5 (4.1)

 HbA1c (%),median (IQR)

6.8 (6.3–7.4)

7.0 (6.5–8.0)

0.004

Lipids, median (IQR)

 Total cholesterol (mmol/L)

4.0 (3.57–4.6)

3.9 (3.4–4.6)

0.146

 Triglycerides (mmol/L)

1.4 (1.0–1.8)

1.5 (1.2–2.1)

0.004

 HDL cholesterol (mmol/L)

1.3 (1.1–1.5)

1.2 (1.0–1.4)

0.001

 LDL cholesterol (mmol/L)

2.1 (1.7–2.5)

2.0 (1.6–2.3)

0.046

 Serum creatinine (umol/L), median (IQR)

75.0 (62.0–89.0)

76.0 (64.0–90.0)

0.413

 eGFR^a (ml/min/1.72m2), median (IQR)

88.0 (73.5–97.9)

88.0 (72.2–98.3)

0.920

 Urine albumin/Creatinine (mg/mmol), median (IQR)

2.0 (1.1–4.7)

3.4 (2.0–10.1)

 < 0.001