The impact of hypertension on retinal nerve fiber layer thickness and its association with carotid intima media thickness

Figures & data

Table I. Comparison of the clinical and biochemical parameters in patients with hypertension and control group.

	Patients with hypertension (n = 59)	Healthy subjects (n = 54)	p
Age (years)	53.6 ± 10.8	51.0 ± 8.2	0.146
Gender (% female)	52.1	47.9	0.514
BMI (kg/m^2)	32.8 ± 5.8	32.1 ± 6.6	0.562
WC (cm)	101.5 ± 10.5	103.9 ± 15.1	0.318
SBP (mmHg)	146.7 ± 19.9	127.5 ± 13.1	< 0.0001
DBP (mmHg)	87.5 ± 10.9	76.4 ± 8.1	< 0.0001
FPG (mg/dl)	100.1 ± 9.4	95.7 ± 7.1	0.006
Total cholesterol (mg/dl)	247.1 ± 33.5	225.5 ± 40.9	0.002
LDL-cholesterol (mg/dl)	162.8 ± 33.9	145.6 ± 38.1	0.018
HDL-cholesterol (mg/dl)	48.2 ± 10.5	51.5 ± 19.7	0.264
Triglyceride (mg/dl)	167.5 ± 79.7	136.8 ± 65.0	0.028
Urea (mg/dl)	30.7 ± 10.33	27.1 ± 7.712	0.039
Creatinine (mg/dl)	0.8 ± 0.2	0.8 ± 0.1	0.247
Uric acid (mg/dl)	6.9 ± 8.1	4.6 ± 1.3	0.044
Microalbuminuria (mg/g)	94.5 ± 266.6	13.7 ± 96.7	0.029
hsCRP (mg/dl)	0.6 ± 0.9	0.5 ± 0.7	0.470
CIMT (mm)	0.8 ± 0.1	0.71 ± 0.1	0.001

Values are expressed as means± SD. BMI, body mass index; WC, waist circumference; SBP, systolic blood pressure; DBP, diastolic blood pressure; FPG, fasting plasma glucose; LDL, low-density lipoprotein; HDL, high-density lipoprotein; hs-CRP, high-sensitive C-reactive protein; CIMT, carotid intima media thickness.

Table II. Retinal nerve fiber layer thickness in patients with hypertension and healthy controls.

Location	RNFL thickness		p-value
	HT	Controls
Average	86.6 ± 10.7	93.6 ± 7.3	< 0.001
Superior	106.9 ± 17.5	118.9 ± 14.7	< 0.001
Temporal	61.7 ± 14.3	63.7 ± 11.1	0.401
Inferior	109.0 ± 18.7	118.6 ± 13.8	0.003
Nasal	68.7 ± 10.9	71.9 ± 12.5	0.150

RNFL, retinal nerve fiber layer; HT, hypertension.

Figure 1. The correlation between average retina nerve fiber layer (RNFL) thickness and carotid intima media thickness (CIMT). The patient who had a CIMT of 1.5 mm was excluded from the calculation.

Table III. The correlation between retinal nerve fiber layer thickness, carotid intima media thickness (CIMT) and cardiometabolic parameters in the study population.

Variable	Average		Superior		Temporal		Inferior		Nasal
	r	p	r	p	r	p	r	p	r	p
Age	− 0.173	0.067	− 0.113	0.235	− 0.172	0.069	− 0.176	0.062	− 0.030	0.755
BMI	0.116	0.223	0.123	0.195	0.029	0.757	0.070	0.464	0.119	0.241
SBP	− 0.127	0.181	− 0.180	0.056	0.008	0.935	− 0.003	0.975	− 0.177	0.061
DBP	− 0.112	0.038	− 0.165	0.082	0.093	0.327	− 0.210	0.026	− 0.225	0.016
FPG	− 0.033	0.733	− 0.054	0.571	0.070	0.460	0.029	0.758	0.120	0.206
Total cholesterol	− 0.066	0.487	0.072	0451	0.073	0.441	− 0.177	0.061	− 0.145	0.124
Triglyceride	0.059	0.536	0.123	0.191	0.038	0.696	0.015	0.873	− 0.049	0.610
LDL-cholesterol	− 0.039	0.680	0.066	0.489	0.144	0.127	− 0.136	0.151	− 0.176	0.062
HDL-cholesterol	0.011	0.680	− 0.023	0.806	− 0.083	0.380	0.009	0.925	0.129	0.173
hsCRP	− 0.010	0.984	0.059	0.536	− 0.094	0.327	− 0.007	0.942	− 0.014	0.880
Uric acid	0.038	0.704	− 0.079	0.427	0.220	0.026	− 0.003	0.973	0.029	0.771
MA	0.002	0.982	− 0.015	0.874	0.169	0.075	− 0.006	0.948	− 0.129	0.175
CIMT	− 0.201	0.034	− 0.185	0.049	− 0.104	0.277	− 0.063	0.508	− 0.156	0.100

r indicates Spearman's rho correlation coefficient; correlation is significant at the 0.05 level. BMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure; FPG, fasting plasma glucose; LDL, low-density lipoprotein; HDL, high-density lipoprotein; hs-CRP, high-sensitive C-reactive protein; MA, microalbuminuria.