Peripheral arterial disease is associated with retinal fluid and microvascular alterations in type 2 diabetes

Table 1 Baseline demographic and clinical characteristics of all participants with type 2 diabetes mellitus based on peripheral arterial disease status, n (%)/mean ± SD

	Patients with type 2 diabetes mellitus		P value
	PAD- (n = 187)	PAD+ (n = 25)
Age, years	56.9 ± 9.7	61.6 ± 8.9	0.023
Sex, male	120 (64.2)	19 (76.0)	0.345
Smoking status			0.267
Never	89 (51.4)	10 (40.0)
Current	42 (24.3)	9 (36.0)
Ex-smoker	42 (24.3)	6 (24.0)
Smoking, pack-years	9.5 ± 14.6	14.5 ± 17.0	0.459
Duration of diabetes, years	17.3 ± 7.7	19.6 ± 10.6	0.310
Medication			0.671
Insulin only	1 (0.5)	0 (0.0)
OHA	121 (64.7)	19 (76.0)
Insulin + OHA	65 (34.8)	6 (24.0)
HTN	79 (42.2)	15 (60.0)	0.202
DR stage			0.793
No DR	23 (12.3)	3 (11.5)
Mild NPDR	81 (43.3)	13 (50.0)
Moderate NPDR	41 (21.9)	6 (23.1)
Severe NPDR	32 (17.1)	4 (15.4)
PDR	10 (5.3)	0 (0.0)
Biological parameters
HbA1c	7.8 ± 1.3	7.5 ± 0.8	0.174
Glucose	148.0 ± 49.4	136.4 ± 30.7	0.111
Total cholesterol	144.1 ± 35.0	146.5 ± 33.4	0.746
Triglyceride	132.8 ± 75.9	125.4 ± 55.7	0.640
HDLc	45.1 ± 11.3	42.4 ± 8.7	0.257
LDLc	89.6 ± 28.2	96.1 ± 30.6	0.284
Creatinine	1.0 ± 0.8	1.1 ± 0.3	0.553
eGFR	82.5 ± 21.7	71.7 ± 18.8	0.018
Clinical parameters
BMI, kg/m2	25.6 ± 3.7	26.3 ± 4.2	0.327
SBP, mmHg	132.0 ± 17.8	144.0 ± 18.3	0.002
DBP, mmHg	74.7 ± 10.5	81.0 ± 12.9	0.006
Visual acuity, logMAR	0.07 ± 0.09	0.04 ± 0.07	0.158
OCTA parameters
SCP fovea VD, %	15.1 ± 4.7	15.6 ± 5.6	0.372
SCP parafoveal VD, %	46.4 ± 3.9	43.9 ± 3.7	0.003
DCP fovea VD, %	28.2 ± 6.0	29.5 ± 8.0	0.409
DCP parafoveal VD, %	49.7 ± 3.8	46.6 ± 3.6	< 0.001
Signal strength	65.8 ± 6.8	66.0 ± 7.4	0.090
OCT parameters
CFT, μm	251.0 ± 23.1	250.2 ± 25.3	0.872
PFT, μm	315.7 ± 16.8	313.7 ± 20.8	0.582
Inner retinal CFT, μm	70.0 ± 12.7	71.0 ± 14.1	0.702
Inner retinal PFT, μm	128.0 ± 9.8	126.6 ± 11.8	0.521

PAD: Peripheral arterial disease; OHA: Oral hypoglycemic agents; HTN: Hypertension; DR: Diabetic retinopathy; NPDR: Non-proliferative diabetic retinopathy; PDR: Proliferative diabetic retinopathy; HbA1c: Glycated hemoglobin; HDLc: High-density lipoprotein cholesterol; LDLc: Low-density lipoprotein cholesterol; eGFR: Estimated glomerular filtration rate; BMI: Body mass index; SBP: Systolic blood pressure; DBP: Diastolic blood pressure; logMAR: Logarithm of the minimum angle of resolution; OCTA: Optical coherence tomography angiography; SCP: Superficial capillary plexus; VD: Vascular density; DCP: Deep capillary plexus; OCT: Optical coherence tomography; CFT: Central foveal thickness; PFT: Parafoveal thickness.