Table 1

Comparisons of clinical characteristics and foveal microcirculation parameters according to diabetic retinopathy grade in patients with type 2 diabetes

NDRNPDRControlP value
No of subjects807575
Age (years)61.2±4.061.8±5.761.2±3.90.654
Gender (male:female)39:4137:3836:390.995
Refractive error (dioptres)–0.39±1.83−0.37±2.19−0.47±1.790.722
Presence of hypertension (n)555217<0.001*
Presence of stroke (n)6520.239
History of insulin treatment (n)10250.002*
Diabetic duration (years)8.3±7.113.9±8.5<0.001†
HbA1c (%)7.3±1.37.8±1.90.040†
Total cholesterol (mg/dL)176±44162±38187±410.002†
Triglyceride (mg/dL)178±102155±89107±530.001†
BUN (mg/dL)15.8±4.818.4±9.315.5±4.00.015†
Creatinine (mg/dL)0.74±0.330.91±0.760.74±0.150.067
Retinal thickness of parafoveal 1–3 mm (µm)310±18.2313±19.1318±16.90.051
mGCIPL thickness (µm)78.7±6.478.5±6.682.3±4.9<0.001†
LogMAR BCVA0.04±0.080.06±0.090.01±0.040.007†
FAZ area (mm2)
 SRL0.38±0.110.38±0.090.33±0.110.001†
 DRL0.58±0.120.59±0.100.48±0.11<0.001†
FAZ perimeter (mm)2.65±0.352.66±0.332.40±0.52<0.001†
FAZ circularity index0.63±0.060.62±0.070.69±0.08<0.001†
Vessel density in SRL
 Parafovea (3×3 mm)17.8±1.8017.5±1.6619.6±1.39<0.001†
 Perifovea (6×6 mm)16.6±1.5516.4±1.6218.3±1.22<0.001†
Perfusion index in SRL
 Parafovea (3×3 mm)0.32±0.030.31±0.030.39±0.05<0.001†
 Perifovea (6×6 mm)0.34±0.050.34±0.040.41±0.05<0.001†
  • 2 analysis=statistically significant at 5% level of significance.

  • †One-way analysis of variance.

  • BCVA, best-corrected visual acuity; BUN, blood urea nitrogen; DRL, deep retinal capillary layer; FAZ, foveal avascular zone; HbA1c, glycated haemoglobin; logMAR, logarithm of the minimum angle of resolution; mGCIPL, macular ganglion cell/inner plexiform layer; NDR, no diabetic retinopathy; NPDR, non-proliferative diabetic retinopathy; SRL, superficial retinal capillary layer.