Association of serum and vitreous homocysteine and uric acid concentrations with post-vitrectomy prognosis in patients with proliferative diabetic retinopathy

Table 1 Baseline characteristics, n (%)/mean ± SD

Variables	Control group (n = 46)	PDR group (n = 44)	T	P value
Male	8 (17.4)	27 (61.4)	20.624	< 0.001a
Age (years)	59.5 ± 4.95	54.59 ± 9.26	49.590	0.099
Serum
FBG (mmol/L)	5.59 ± 0.72	5.78 ± 1.35	72.682	0.905
HbA1c	6.04 ± 0.70	7.30 ± 1.22	47.781	0.003a
Hcy (μmol/L)	11.21 ± 2.76	15.10 ± 6.92	72.136	0.005a
UA (μmol/L)	287.67 ± 85.77	397.79 ± 97.55	71.468	0.381
BUN (mmol/L)	5.11 ± 1.52	10.85 ± 6.54	65.065	0.01a
Crea (μmol/L)	68.3 ± 12.73	165.09 ± 195.37	54.824	0.263
eGFR (mL/minute/m2)	85.4 ± 13.94	65.63 ± 36.46	78.432	0.396
UACR (mg/g)	15.7 ± 17.74	842.50 ± 1347.98	47.424	0.075
CysC (mg/L)	0.97 ± 0.12	1.97 ± 1.50	67.702	< 0.001a
Vitreous
Hcy (μmol/L)	0.82 ± 0.49	2.66 ± 1.46	30.935	< 0.001a
UA (μmol/L)	45.17 ± 37.18	198.84 ± 76.86	0.811	< 0.001a

^aP < 0.05.

FBG: Fasting blood glucose; HbA1c: Hemoglobin A1c; Hcy: Homocysteine; UA: Uric acid; BUN: Blood urea nitrogen; Crea: Creatinine; eGFR: Estimated glomerular filtration rate; UACR: Urinary albumin-to-creatinine ratio; CysC: Cystatin C.

Table 2 Correlation analysis of vitreous homocysteine and uric acid, and serum indicators within the proliferative diabetic retinopathy group (n = 44)

Serum variables	Vitreous Hcy		Vitreous UA
	Pearson	P value	Pearson	P value
FBG (mmol/L)	-0.108	0.492	-0.135	0.338
HbA1c (%)	0.049	0.759	0.097	0.542
Hcy (μmol/L)	0.554	< 0.001a	0.472	0.001a
UA (μmol/L)	0.157	0.309	0.480	< 0.001a
BUN (mmol/L)	0.496	< 0.001a	0.591	< 0.001a
Crea (μmol/L)	0.570	< 0.001a	0.552	< 0.001a
eGFR (mL/minute/m2)	-0.521	< 0.001a	-0.588	< 0.001a
CysC (mg/L)	0.584	< 0.001a	0.530	< 0.001a
UACR (mg/g)	0.318	0.071	0.407	0.019a

^aP < 0.05.

Hcy: Homocysteine; UA: Uric acid; FBG: Fasting blood glucose; HbA1c: Hemoglobin A1c; BUN: Blood urea nitrogen; Crea: Creatinine; eGFR: Estimated glomerular filtration rate; UACR: Urinary albumin-to-creatinine ratio; CysC: Cystatin C.

Table 3 Correlation of serum homocysteine, uric acid, and best-corrected visual acuity, superficial capillary plexus within the proliferative diabetic retinopathy group (n = 44)

Variables	Time	Serum Hcy (μmol/L)		Serum UA (μmol/L)
		Pearson	P value	Pearson	P value
BCVA (logMAR)	7 days	-0.029	0.866	-0.079	0.643
	30 days	-0.150	0.474	0.068	0.749
	90 days	-0.046	0.877	0.040	0.893
SCP vessel length density (mm)	7 days	-0.214	0.063	-0.056	0.632
	30 days	-0.116	0.332	-0.154	0.196
	90 days	-0.183	0.115	-0.172	0.141
SCP vessel width density (mm2)	7 days	-0.223	0.053	-0.009	0.936
	30 days	-0.042	0.724	-0.053	0.656
	90 days	-0.126	0.282	-0.170	0.144

Hcy: Homocysteine; UA: Uric acid; BCVA: Best-corrected visual acuity; SCP: Superficial capillary plexus; logMAR: Logarithmic minimum angle of resolution.

Table 4 Correlation analysis of vitreous homocysteine, uric acid, and best-corrected visual acuity, optical coherence tomography parameters within the proliferative diabetic retinopathy group (n = 44)

Variables	Time	Vitreous Hcy (μmol/L)		Vitreous UA (μmol/L)
		Pearson	P value	Pearson	P value
BCVA (logMAR)	1 day	0.594	0.006a	-0.064	0.787
	7 days	0.261	0.113	0.027	0.871
	30 days	0.156	0.448	-0.086	0.676
	90 days	0.264	0.361	0.093	0.753
pRNFL
Optic daysisc	7 days	-0.164	0.354	-0.107	0.548
	30 days	-0.149	0.440	-0.102	0.597
	90 days	-0.382	0.054	-0.297	0.141
Temporal	7 days	-0.105	0.553	-0.046	0.794
	30 days	0.032	0.869	0.057	0.771
	90 days	-0.085	0.631	-0.376	0.058
Superior temporal	7 days	-0.029	0.866	-0.216	0.199
	30 days	0.046	0.804	-0.243	0.180
	90 days	-0.399	0.036a	-0.285	0.142
Inferior temporal	7 days	-0.155	0.361	-0.055	0.745
	30 days	-0.039	0.818	0.053	0.754
	90 days	-0.057	0.747	-0.042	0.812
Nasal	7 days	0.112	0.530	-0.033	0.852
	30 days	-0.113	0.559	-0.132	0.494
	90 days	-0.107	0.603	-0.131	0.523
Superior nasal	7 days	0.118	0.506	-0.002	0.993
	30 days	0.179	0.353	0.032	0.871
	90 days	-0.054	0.761	-0.058	0.743
Inferior nasal	7 days	-0.354	0.043a	0.177	0.323
	30 days	-0.268	0.160	0.065	0.737
	90 days	-0.716	< 0.001a	-0.343	0.086
CMT and SFCT
CMT	7 days	-0.105	0.531	-0.078	0.642
	30 days	-0.114	0.526	-0.043	0.812
	90 days	-0.166	0.400	-0.085	0.669
SFCT	7 days	-0.023	0.894	-0.059	0.727
	30 days	-0.059	0.726	-0.210	0.248
	90 days	-0.012	0.953	-0.080	0.693

^aP < 0.05.

Hcy: Homocysteine; UA: Uric acid; BCVA: Best-corrected visual acuity; LogMAR: Logarithmic minimum angle of resolution; OCT: Optical coherence tomography angiography; pRNFL: Peripapillary retinal nerve fiber layer; CMT: Central macular thickness; SFCT: Subfoveal choroid thickness.

Table 5 Correlation analysis of vitreous homocysteine and uric acid with optical coherence tomography angiography parameters within the proliferative diabetic retinopathy group (n = 44)

Variables	Time	Vitreous Hcy (μmol/L)		Vitreous UA (μmol/L)
		Pearson	P value	Pearson	P value
SCP length density (mm-1)
Superior	7 days	0.015	0.927	0.18	0.261
	30 days	-0.025	0.882	-0.179	0.288
	90 days	0.021	0.898	0.021	0.9
Inferior	7 days	-0.15	0.348	-0.089	0.581
	30 days	-0.013	0.941	0.246	0.143
	90 days	-0.059	0.72	0.018	0.915
Nasal	7 days	-0.063	0.697	0.133	0.407
	30 days	0.255	0.128	-0.413	0.011a
	90 days	-0.058	0.726	0.141	0.392
Temporal	7 days	-0.199	0.212	-0.114	0.476
	30 days	0.06	0.725	0.178	0.292
	90 days	-0.101	0.542	-0.163	0.323
Fovea	7 days	-0.084	0.604	0.066	0.681
	30 days	0.132	0.443	-0.232	0.174
	90 days	-0.22	0.183	-0.009	0.959
Inner ring	7 days	-0.199	0.213	-0.106	0.51
	30 days	0.024	0.883	0.252	0.108
	90 days	-0.196	0.22	-0.013	0.935
Full area	7 days	-0.158	0.307	0.221	0.15
	30 days	-0.01	0.949	0.195	0.215
	90 days	-0.12	0.941	0.1	0.543
SCP width density (mm-2)
Superior	7 days	-0.255	0.108	0.032	0.84
	30 days	-0.006	0.974	-0.083	0.624
	90 days	0.006	0.973	-0.005	0.978
Inferior	7 days	-0.303	0.014a	0.00	1.00
	30 days	0.032	0.85	0.057	0.737
	90 days	-0.07	0.67	-0.009	0.957
Nasal	7 days	-0.157	0.326	0.134	0.405
	30 days	0.18	0.287	0.313	0.06
	90 days	0.027	0.869	-0.007	0.967
Temporal	7 days	-0.237	0.136	0.134	0.403
	30 days	0.278	0.096	-0.391a	0.017a
	90 days	0.143	0.385	-0.205	0.21
Fovea	7 days	-0.238	0.134	0.026	0.874
	30 days	-0.074	0.662	-0.109	0.522
	90 days	-0.096	0.56	-0.015	0.93
Inner ring	7 days	-0.291	0.065	-0.067	0.667
	30 days	-0.151	0.372	-0.341	0.039a
	90 days	0.136	0.408	0.197	0.23
Full area	7 days	-0.3	0.057	-0.073	0.651
	30 days	0.139	0.412	0.315	0.057
	90 days	-0.001	0.997	0.115	0.485
FAZ
FAZ (mm2)	7 days	-0.157	0.326	-0.008	0.959
	30 days	0.177	0.294	0.134	0.428
	90 days	0.343a	0.032a	0.041	0.803
The perimeter of FAZ (mm)	7 days	-0.158	0.325	-0.108	0.503
	30 days	0.084	0.621	-0.013	0.941
	90 days	0.208	0.204	0.03	0.858

^aP < 0.05.

Hcy: Homocysteine; UA: Uric acid; OCTA: Optical coherence tomography angiography; SCP: Superficial capillary plexus; FAZ: Foveal avascular zone.