The study included a total of 76 patients with RVO, comprising 37 with CRVO and 39 with BRVO, and 76 controls without retinal vascular pathologies. There was no significant difference between the two groups in terms of age and gender (p = 0.161 and 0.061, respectively); however, a significant difference was found in BCVA and CMT (p < 0.001 and 0.001, respectively) (Table 1).
Table 1
Hematological parameters and demographic characteristics of the groups
Variables
|
RVO
|
Control
|
p
|
Gender (f/M)
|
42/34
|
39/46
|
0.061
|
age (year)
|
62.04 ± 10.28
|
59.84 ± 8.91
|
0.161
|
BCVA (Logmar)
|
1.39 ± 1.30
|
0.028 ± 1.22
|
<.001
|
BMI (kg/m2)
|
24.80 ± 1.34
|
24.20 ± 1.37
|
0.010
|
Diabetes n (%)
|
31 (40.8)
|
13 (17.1)
|
0.002
|
Hypertension n (%)
|
48 (63.2)
|
15 (19.7)
|
0.001
|
Hyperlipidemia n (%)
|
28 (36.8)
|
7 (9.2)
|
0.001
|
CAD n (%)
|
16 (21.1)
|
8 (10.5)
|
0.118
|
Smoking n (%)
|
26 (34.2)
|
15 (19.7)
|
0.067
|
CMT (µm)
|
588.76 ± 104.02
|
265.20 ± 45.11
|
0.001
|
TG (mg/dL)
|
166.1 ± 58.3
|
155.9 ± 76.6
|
0.360
|
TC (mg/dL)
|
188.2 ± 28.6
|
178.3 ± 45.6
|
0.114
|
HDL (mg/dL)
|
43.4 ± 7.6
|
44.7 ± 9.8
|
0.355
|
LDL (mg/dL)
|
115.5 ± 39.1
|
107.3 ± 39.4
|
0.201
|
ESR (mm/sa)
|
19.9 ± 17.7
|
18.8 ± 11.4
|
0.667
|
crp (mg/dL)
|
0.72 ± 1.67
|
0.83 ± 1.01
|
0.622
|
d-dimer (ng/mL)
|
481.8 ± 421.6
|
309.4 ± 161.6
|
0.012
|
Hgb (g/dL)
|
14.7 ± 1.69
|
13.9 ± 2.91
|
0.036
|
Htc (%)
|
46.1 ± 6.2
|
42.0 ± 8.5
|
0.011
|
K
|
4.26 ± 0.41
|
4.23 ± 0.65
|
0.713
|
Na
|
140.1 ± 3,6
|
138.8 ± 3.5
|
0.064
|
AST
|
18.6 ± 6.9
|
17.4 ± 6.7
|
0.290
|
ALT
|
18.7 ± 11.1
|
16.7 ± 7.8
|
0.198
|
Urea
|
42.6 ± 15.1
|
38.4 ± 22.9
|
0.185
|
Independant Sample t test, Chi-Square test |
CRVO: Central Retinal Vein Occlusion, BRVO: Branch Retinal Vein Occlusion, BCVA: Best Corrected Visual Acuity, BMI: Body Mass Index, CAD: Coronary Artery Disease, CMT: Central Macular Thickness, TG: Triglyceride, TC: Total Cholesterol, HDL: High-Density Lipoprotein, LDL: Low-Density Lipoprotein, ESR: Erythrocyte Sedimentation Rate, CRP: C-Reactive Protein, Hgb: Hemoglobin, Htc: Hemotocrit |
While there was a significant difference between the two groups in terms of the presence of diabetes, hypertension, and hyperlipidemia (p = 0.002, 0.001, and 0.001, respectively), no significant difference was observed in relation to smoking status and CAD (p = 0.118 and 0.067, respectively). The TG, TC, HDL, LDL, ESR, CRP, Na, K, AST, ALT and urea values did not statistically significantly differ between the RVO and control groups (p = 0.360, 0.114, 0.355, 0.201, 0.667, 0.622, 0.064, 0.713, 0.290, 0.198, and 0.185 respectively), but there was a significant difference in D-dimer, Hgb, Htc (p = 0.012, 0.036, and 0.011, respectively) (Table 1).
There was no significant difference between the RVO and control groups in the basal and maximum brachial artery diameters (p = 0.676 and 0.139, respectively); however, a statistically significant difference was detected in FMD, PWV, and CIMT on both sides (p < 0.001 for all) (Table 2).
Table 2
FMD, PWV and CIMT values according to groups.
Variables
|
RVO
|
Control
|
p
|
Brachial artery Basal Diameter (mm)
|
5.08 ± 0.62
|
5.12 ± 0.57
|
0.676
|
Brachial Artery Maximum Diameter (mm)
|
5.42 ± 0.65
|
5.58 ± 0.63
|
0.139
|
FMD (%)
|
6.57 ± 2.41
|
8.82 ± 1.97
|
<.001
|
PWV (m/sn)
|
6.67 ± 0.71
|
6.12 ± 0.19
|
<.001
|
Right CIMT (mm)
|
0.76 ± 0.08
|
0.64 ± 0.09
|
<.001
|
Left CIMT (mm)
|
0.75 ± 0.09
|
0.64 ± 0.09
|
<.001
|
Independant Sample t test |
RVO: Retinal Vein Occlusion, FMD: Flow-mediated Dilation, CIMT: Carotid Intima Media Thickness, PWV: Pulse Wave Velocity |
The binary logistic regression analysis was performed for the parameters found to be significant risk factors for RVO using the chi-square test (diabetes, hypertension, and hyperlipidemia). The results were as follows: diabetes OR: 0.460, 95% CI: 0.704–3.567, p = 0.266; hypertension OR: 1.455, 95% CI: 1.981–9.272, p = 0.001, and hyperlipidemia OR: 0.124, 95% CI: 0.371–3.456, p = 0.828 (Table 3). A multivariate regression analysis was also conducted for the risk factors that were found to be related to RVO in the univariate analysis (BMI, D-Dimer, Hgb, Htc, FMD, PWV, and the right and left CIMT). The results of this analysis were: d-Dimer OR: 0.015, 95% CI: 0.000-0.001, p < 0.001); Htc OR: 0.021, 95% CI: 0.008–0.035, p = 0.002, FMD OR: 0.050, 95% CI: 0.020–0.080, p = 0.001; PWV OR 0.392, 95% CI: 0.271–0.513, p < 0.001), right CIMT OR: 2.434, 95% CI: 1.801–3.055, p < 0.001), and left CIMT OR: 2.284, 95% CI: 1.646–2.922, p < 0.001) (Table 4).
Table 3
Independent predictors of RVO with binary logistic regression analysis P-value, OR with 95% CI
Variable
|
p-value
|
Odd ratio
|
95% C.I.
|
Diabetes n (%)
|
0.266
|
0.460
|
0.704–3.567
|
Hypertension n (%)
|
0.001
|
1.455
|
1.981–9.272
|
Hyperlipidemia n (%)
|
0.828
|
0.124
|
0.371–3.456
|
Binary Logistic Regression Analysis |
Table 4
Independent predictors of RVO with univariate and multivariate P-value, OR with 95% CI
Variable
|
Univariate analysis of RVO
P-value Odd ratio 95% C.I
|
Multivariate analysis of RVO
P-value Odd ratio 95% C.I.
|
BMI (kg/m2)
|
0.010
|
0.076
|
0.019–0.133
|
0.130
|
0.036
|
0.011–0.083
|
D-dimer (ng/mL)
|
0.015
|
< .001
|
0.000-0.001
|
0.152
|
< .001
|
< .001-<.001
|
Hgb (g/dL)
|
0.145
|
0.034
|
0.012–0.080
|
0.599
|
0.015
|
0.041–0.071
|
Htc (%)
|
0.002
|
0.021
|
0.008–0.035
|
0.309
|
0.009
|
0.008–0.026
|
FMD (%)
|
< .001
|
0.093
|
0.122 − 0.064
|
0.001
|
0.050
|
0.020–0.080
|
PWV (m/sn)
|
< .001
|
0.392
|
0.271–0.513
|
0.842
|
0.015
|
0.136–0.167
|
Right CIMT (mm)
|
< .001
|
2.434
|
1.801–3.055
|
0.086
|
2.203
|
0.317–4.724
|
Left CIMT (mm)
|
< .001
|
2.284
|
1.646–2.922
|
0.613
|
0.647
|
1.898–3.173
|
Univariant and Multivariant Lineer Logistic Regression |
RVO: Retinal Vein Occlusion, BMI: Body Mass Index, HGB: Hemoglobin, HTC: Hemotocrit,, FMD: Flow-mediated Dilation, PWV: Pulse Wave Velocity, CIMT: Carotid Intima Media Thickness, |
The PWV and CIMT values were significantly higher and the FMD values were significantly lower in patients with CRVO than those with BRVO, suggesting that systemic endothelial disfunction was more severe in the former. (Fig. 1)