Table 2.
Multiple regression models of (a) foveal avascular zone area, (b) vessel density, (c) fractal dimension with variables that showed significant associations in univariate analysis
| Beta coefficient | Standard error | 95% CI | P-value | |
|---|---|---|---|---|
| (a) Foveal Avascular Zone (FAZ) Area | ||||
| Severity of DR | ||||
| Severe NPDR or PDR vs. No DR | 0.687 | 0.330 | 0.041 to 1.333 | 0.037 |
| Moderate NPDR vs. No DR | 0.103 | 0.148 | −0.187 to 0.392 | 0.487 |
| Mild NPDR vs. No DR | 0.221 | 0.130 | −0.034 to 0.475 | 0.089 |
| Presence of DME | 0.138 | 0.171 | − 0.196 to 0.473 | 0.418 |
| LogMAR, per SD increase | 0.102 | 0.058 | −0.012 to 0.215 | 0.079 |
| Axial length, per SD increase | −0.171 | 0.057 | −0.282 to − 0.059 | 0.003 |
| Subfoveal choroidal thickness, per SD increase | −0.122 | 0.056 | −0.232 to − 0.011 | 0.031 |
| Body mass index, per SD increase | −0.090 | 0.046 | −0.180 to − 0.001 | 0.047 |
| Systolic blood pressure, per SD increase | 0.077 | 0.067 | −0.053 to 0.207 | 0.246 |
| Age, per SD increase | 0.051 | 0.053 | −0.052 to 0.154 | 0.336 |
| (b) Vessel Density (VD) | ||||
| Severity of DR | ||||
| Severe NPDR or PDR vs. No DR | −0.842 | 0.245 | −1.322 to − 0.363 | 0.001 |
| Moderate NPDR vs. No DR | −0.249 | 0.145 | −0.532 to 0.035 | 0.085 |
| Mild NPDR vs. No DR | −0.345 | 0.124 | −0.588 to − 0.101 | 0.006 |
| Presence of DME | −0.160 | 0.167 | −0.488 to 0.168 | 0.340 |
| Axial length, per SD increase | 0.107 | 0.052 | 0.005 to 0.209 | 0.039 |
| LogMAR, per SD increase | −0.133 | 0.057 | −0.245 to − 0.020 | 0.021 |
| Subfoveal choroidal thickness, per SD increase | 0.104 | 0.056 | −0.005 to 0.213 | 0.062 |
| Body mass index, per SD increase | 0.073 | 0.054 | −0.033 to 0.178 | 0.176 |
| Systolic blood pressure, per SD increase | −0.030 | 0.057 | −0.143 to 0.082 | 0.595 |
| Age, per SD increase | −0.078 | 0.058 | −0.192 to 0.036 | 0.182 |
| (c) Fractal Dimension (FD) | ||||
| Severity of DR | ||||
| Severe NPDR or PDR vs. No DR | −0.891 | 0.225 | −1.331 to − 0.451 | < 0.001 |
| Moderate NPDR vs. No DR | −0.357 | 0.128 | −0.607 to − 0.107 | 0.005 |
| Mild NPDR vs. No DR | −0.307 | 0.109 | −0.521 to − 0.093 | 0.005 |
| LogMAR, per SD increase | −0.074 | 0.055 | −0.183 to 0.034 | 0.180 |
| Average GC-IPL, per SD increase | 0.113 | 0.054 | 0.007 to 0.220 | 0.037 |
| Body mass index, per SD increase | 0.077 | 0.037 | 0.005 to 0.149 | 0.035 |
| Systolic blood pressure, per SD increase | 0.062 | 0.045 | −0.026 to 0.151 | 0.168 |
| Age, per SD increase | −0.142 | 0.050 | −0.239 to − 0.044 | 0.004 |
CI= confidence interval; SD= standard deviation; DR= diabetic retinopathy; NPDR= non-proliferative diabetic retinopathy; PDR= proliferative diabetic retinopathy; DME= diabetic macular edema; GC-IPL= ganglion cell inner plexiform layer; LogMAR= logarithm of the minimum angle of resolution