Incidence of diabetic retinopathy onset by different risk factors
| At risk (n) | Incidence, % (95% CI) | Age, sex-adjusted RR (95% CI) | P value | Multivariate RR (95% CI) | P value | |
| Age (years) | – | – | 0.99 (0.97 to 1.02) | 0.62 | 0.99 (0.96 to 1.02) | 0.55 |
| Sex* | ||||||
| Male | 323 | 5.4 (3.0 to 7.9) | Reference | Reference | ||
| Female | 439 | 6.1 (3.8 to 8.3) | 0.95 (0.59 to 1.53) | 0.84 | 1.21 (0.72 to 2.02) | 0.46 |
| Duration of diabetes (years) | ||||||
| <5 | 383 | 6.5 (4.1 to 9.0) | Reference | Reference | ||
| 5–10 | 237 | 8.4 (4.9 to 12.0) | 1.32 (0.74 to 2.36) | 0.34 | 1.13 (0.66 to 1.96) | 0.65 |
| ≥10 | 142 | 13.4 (7.8 to 19.0) | 2.13 (1.19 to 3.81) | 0.01 | 1.95 (1.09 to 3.50) | 0.02 |
| FPG (mmol/L) | ||||||
| <9 | 526 | 7.6 (5.3 to 9.9) | Reference | Reference | ||
| 9–12 | 150 | 8.0 (3.7 to 12.3) | 1.05 (0.57 to 1.95) | 0.87 | 0.57 (0.30 to 1.07) | 0.08 |
| ≥12 | 81 | 14.8 (7.1 to 22.5) | 1.95 (1.03 to 3.68) | 0.04 | 0.72 (0.34 to 1.54) | 0.40 |
| HbA1c (%) | ||||||
| <7 | 361 | 5.5 (3.2 to 7.9) | Reference | Reference | ||
| 7–9 | 273 | 9.2 (5.7 to 12.6) | 1.65 (0.94 to 2.90) | 0.08 | 1.68 (0.95 to 2.97) | 0.07 |
| ≥9 | 123 | 15.5 (9.1 to 21.8) | 2.79 (1.55 to 5.02) | <0.001 | 2.95 (1.54 to 5.67) | 0.001 |
| Current smoking | ||||||
| No | 575 | 7.7 (5.5 to 9.8) | Reference | Reference | ||
| Yes | 171 | 11.7 (6.9 to 16.5) | 1.64 (0.96 to 2.80) | 0.07 | 1.69 (0.96 to 2.95) | 0.07 |
| SBP (mmHg) | ||||||
| <140 | 343 | 7.3 (4.5 to 10.0) | Reference | Reference | ||
| 140–170 | 331 | 8.2 (5.2 to 11.1) | 1.15 (0.68 to 1.96) | 0.60 | 1.05 (0.61 to 1.80) | 0.85 |
| ≥170 | 88 | 13.6 (6.5 to 20.8) | 2.00 (1.03 to 3.90) | 0.04 | 2.19 (1.12 to 4.30) | 0.02 |
| Proteinuria | ||||||
| No | 567 | 6.7 (4.6 to 8.8) | Reference | Reference | ||
| Yes | 193 | 13.5 (8.7 to 18.3) | 2.02 (1.26 to 3.23) | 0.003 | 1.94 (1.19 to 3.17) | 0.01 |
| CRVE (μm) | ||||||
| <210 | 207 | 6.8 (3.3 to 10.2) | Reference | Reference | ||
| 210–250 | 444 | 7.7 (5.2 to 10.1) | 1.13 (0.61 to 2.08) | 0.70 | 1.10 (0.59 to 2.04) | 0.76 |
| ≥250 | 103 | 15.5 (8.5 to 22.5) | 2.28 (1.15 to 4.52) | 0.02 | 2.17 (1.09 to 4.32) | 0.03 |
| Total† | 762 | 5.8 (4.7 to 6.9) | – | – | – | – |
Bold values denote p<0.05.
*Age-standardised prevalence.
†Age-standardised and sex-standardised prevalence. Both were standardised to the year 2010 China population census data.
RR, relative risk; FPG, fasting plasma glucose; HbA1c, glycosylated haemoglobin A1c; SBP, systolic blood pressure; CRVE, central retinal vein equivalent.