Table 5. Simple and multiple linear regression analyses for D(f).
| Univariate | Multivariate | |||
| β (95% CI) | P value | β (95% CI) | P value | |
| Age, y | −0.0018 (−0.0019, −0.0016) | <0.001 * | −0.0012 (−0.0014, −0.001) | <0.001 * |
| Gender | ||||
| Females (ref: males) | 0.0033 (−0.0013, 0.0078) | 0.157 | ||
| BMI, kg/m2 | ||||
| 24–28 (ref: <24) | −0.0081 (−0.0129, −0.0033) | 0.001 * | 0.0024 (−0.0026, 0.0074) | 0.349 |
| >28 (ref: <24) | −0.0172 (−0.0246, −0.0098) | <0.001 * | 0.0001 (−0.0076, 0.0078) | 0.976 |
| SBP, mm Hg | −0.0008 (−0.0009, −0.0007) | <0.001 * | ||
| DBP, mm Hg | −0.0010 (−0.0012, −0.0008) | <0.001 * | ||
| MAP, mm Hg | −0.0011 (−0.0013, −0.0010) | <0.001 * | −0.0002 (−0.0004, 0) | 0.105 |
| PP, mm Hg | −0.0010 (−0.0011, −0.0009) | <0.001 * | −0.0001 (−0.0003, 0) | 0.151 |
| Blood pressure classification | ||||
| Prehypertension (ref: Normal) | −0.0188 (−0.0241, −0.0136) | <0.001 * | ||
| Hypertension (ref: Normal) | −0.0427 (−0.0476, −0.0378) | <0.001 * | −0.0075 (−0.0134, −0.0015) | 0.014 * |
| HR, beats per minute | −0.0001 (−0.0003, 0.0001) | 0.432 | −0.0131 (−0.0216, −0.0047) | 0.002 * |
| Smoking | ||||
| Current or former (ref: Never) | −0.0009 (−0.0065, 0.0047) | 0.746 | ||
| Alcohol consumption | ||||
| Current or former (ref: Never) | −0.0019 (−0.0079, 0.0042) | 0.540 | ||
| Diabetes | ||||
| Present (ref: Absent) | −0.0186 (−0.0252, −0.0120) | <0.001 * | −0.0029 (−0.0093, 0.0035) | 0.376 |
| Hypertension | ||||
| Present (ref: Absent) | −0.0291 (−0.0336, −0.0246) | <0.001 * | −0.007 (−0.0121, −0.0018) | 0.009 * |
| Metabolic syndrome | ||||
| Present (ref: Absent) | −0.0108 (−0.0152, −0.0065) | <0.001 * | −0.0024 (−0.0075, 0.0028) | 0.363 |
| TG, mmol/L | 0.0084 (0.0040, 0.0127) | <0.001 * | 0.0026 (−0.0017, 0.0069) | 0.243 |
| TC, mmol/L | −0.0038 (−0.0059, −0.0017) | <0.001 * | 0.003 (−0.0002, 0.0062) | 0.07 |
| HDL-C, mmol/L | −0.0018 (−0.0085, 0.0049) | 0.597 | ||
| LDL-C, mmol/L | −0.0071 (−0.0095, −0.0046) | <0.001 * | −0.0037 (−0.0075, 0.0002) | 0.062 |
| FPG, mmol/L | −0.0014 (−0.0029, 0.0001) | 0.061 | ||
| Uric Acid, µmol/L | −0.00002 (−0.0001, 0.000003) | 0.083 | ||
| HbA1c, % | −0.0123 (−0.0155, −0.0091) | <0.001 * | ||
| hs-CRP, mg/L† | −0.0084 (−0.0102, −0.0066) | <0.001 * | −0.0005 (−0.0024, 0.0013) | 0.563 |
BMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure; MAP, mean arterial pressure; PP, pulse pressure; HR, heart rate; TG, triglyceride; TC, total cholesterol; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; FPG, fasting plasma glucose; HbA1c, glycated hemoglobin; hs-CRP, high-sensitivity C-reactive protein; CRAE, central retinal arteriolar equivalent; CRVE, central retinal venular equivalent; D(f), retinal vascular fractal dimension.
β (95% CI): regression coefficient and 95% confidence interval.
*P<0.05 indicates a significant association with D(f).
†
Log transformation was applied.
The R2 for the multivariable regression model was 0.2031.