Burden of diabetic retinopathy in mainland China: Protocol for an updated systematic review and meta-analysis of prevalence and risk factors to identify prevention policies

AST/ALT ratio is an independent risk factor for diabetic retinopathy: A cross-sectional study

The aspartate to alanine transaminase (AST/ALT) ratio indicates oxidative stress and inflammatory reactions related to the occurrence of diabetic retinopathy (DR). Currently, there are no reports on the correlation between AST/ALT ratio and DR. Hence, this study aimed to explore the relationship between AST/ALT ratio and DR. This cross-sectional study utilized data from the Metabolic Management Center of the First People's Hospital in City. In total, 1365 patients with type 2 diabetes mellitus (T2DM) participated in the study, including 244 patients with DR and 1121 patients without DR. We collected the results of fundus photography, liver function, and other research data and grouped them according to tertiles of AST/ALT ratios. DR prevalence was the highest in the group with the highest AST/ALT ratio (22.12%, P = .004). Both univariate (OR = 2.25, 95% CI: 1.51-3.34, P < .001) and multivariable logistic regression analyses (adjusted for confounding factors) showed that the risk of DR increased by 36% when the AST/ALT ratio increased by 1 standard deviation (SD) (OR = 1.36, 95% CI: 1.16-1.59, P < .001), and 29.3% was mediated by the duration of diabetes. A sensitivity analysis confirmed the stability of the results. This study showed that an increase in AST/ALT ratio is an independent risk factor for DR.

Comparative study of the vascular structures of the retina and choroid in Chinese Han and Uygur populations with proliferative diabetic retinopathy: An OCTA study

BACKGROUND

To compare the vascular structures of the retina and choroid in Chinese Han and Uygur populations with proliferative diabetic retinopathy (PDR) using swept-source OCTA (SS-OCTA).

METHODS

Fifty-three eyes of 53 healthy volunteers (25 from Hans and 28 from Uygurs) and 40 eyes of 40 PDR patients (20 from Hans and 20 from Uygurs) were included. Retinal and choroidal parameters, including thickness, vessel flow density (VFD), foveal avascular zone (FAZ) area, choroidal vascularity volume and index (CVV and CVI) were evaluated.

RESULTS

Compared with the respective controls, superficial capillary plexus (SCP)-VFD and deep capillary plexus (DCP)-VFD, the areas of FAZ in SCP and DCP were significantly decreased in both Han and Uygur PDR patients. choroidal parameters analysis found that Uygur controls had substantially higher choroidal thickness (CT) than Han controls (p = 0.020) and PDR eyes showed significantly decreased CT. Both races with PDR exhibited significantly reduced choriocapillaris layer-VFD, large and medium choroidal vessel (LMCV) layer-VFD, CVV and CVI, however, Uygur PDR patients had significant lower LMCV layer-VFD, CVV and CVI compared to Han PDR patients. Diabetes duration was the most significant factor affecting CVV and CVI.

CONCLUSION

Both Han and Uygur PDR patients had significantly lower CT and decreased vessel densities compared to controls, but the Uygur PDR patients had more severe choroidal damage than Han PDR patients, which is most likely related to worse visual prognosis. These findings indicate that more frequent screenings and prompt therapy are urgent for Uygur PDR patients.

The effect of a new design of patient gowns for prone position patients after vitrectomy: A non-randomized, concurrent, controlled study

BACKGROUND

The existing patient clothing is not suitable for patients that have to maintain a prone position for a long time after vitrectomy.

OBJECTIVE

To investigate the effect of a new design of patient gowns for prone position patients after vitrectomy.

METHOD

This study designed a kind of patient's gown for prone position patients. A non-randomized, concurrent, controlled study was conducted on 212 patients who met the inclusion criteria for the prone position after vitrectomy in Grade III at a Class A hospital department of ophthalmology in Zhejiang Province from April to August 2020. The experimental group (106 patients in prone position) and the control group (106 patients in common position) were managed by the same group of nurses. The study recorded and compared the comfort degree of patients' clothing used in the course of operation rehabilitation between the two groups and the satisfaction degree of doctors with nurses to patients' clothing used in the prone position.

RESULTS

The satisfaction degree and comfort degree of patients and the health care providers in the experiment group were significantly higher than those in the control group (p< 0.001).

CONCLUSION

The process of making patient gowns for prone position patients is simple, which can improve the safety and comfort of patients when they were in the prone position. The new design also facilitated the treatment and nursing procedures of the medical staff and improved satisfaction among patients and medical staff.

Serum Untargeted Metabolomics Reveal Potential Biomarkers of Progression of Diabetic Retinopathy in Asians

Purpose: To reveal molecular mechanisms of diabetic retinopathy (DR) in Asians and facilitate the identification of new therapeutic targets through untargeted metabolomics. To determine the differences in serum metabolites and metabolic pathways between different stages of diabetic retinopathy in patients with type 2 diabetic mellitus (T2DM) and proliferative DR (PDR) and non-proliferative DR (NPDR) and identify differential metabolites between T2DM and DR (NPDR and PDR) patients. Methods: This prospective observational registration study described the differential metabolites between 45 T2DM patients and 15 control cases with no significant differences in clinical characteristics. Their biospecimens and clinical information were collected and recorded in their medical reports. DR phenotypes of the subjects were verified by retina specialists. Serum metabolites were analyzed using high-resolution mass spectrometry with liquid chromatography. Untargeted metabolomics was performed on serum samples from 15 T2DM patients, 15 non-proliferative diabetic retinopathy patients, 15 proliferative diabetic retinopathy patients, and 15 diabetic controls. Discriminatory metabolic features were identified through partial least squares discriminant analysis (PLS-DA), hierarchical clustering analysis (HCA), and generalized linear regression models. Result: Through untargeted metabolomics, 931 features (523 in positive and 408 in negative modes) with 102 common metabolites highly relevant to the presence of DR were detected. In the adjusted analysis, 67 metabolic features differed significantly between T2DM and NPDR patients. Pathway analysis revealed alterations in metabolisms of amino acids and fatty acids. Glutamate, phosphatidylcholine, and 13-hydroperoxyoctadeca-9,11-dienoic acid (13-PHODE) were key contributors to these pathway differences. A total of 171 features distinguished PDR patients from T2DM patients, and pathway analysis revealed alterations in amino acid metabolism, fatty acid metabolism, nitrogen metabolism, and tricarboxylic acid cycle. Aspartate, glutamate, glutamine, ornithine, N-acetyl-l-glutamate, N-acetyl-l-aspartate, citrate, succinate, N-(L-arginino)succinate, 2-oxoglutarate, 13-hydroperoxyoctadeca-9,11-dienoic acid, methionine, lysine, threonine, phenylalanine, N(pi)-methyl-l-histidine, phosphatidylcholine, and linoleate were major contributors to the pathway differences. Between NPDR patients and PDR patients, there were 79 significant differential metabolites. Enrichment pathway analysis showed changes in amino acid metabolism, fatty acid metabolism, pantothenate, and CoA biosynthesis. Aspartate, glutamine, N-acetyl-l-glutamate, N-acetyl-l-aspartate, pantothenate, dihomo-gamma-linolenate, docosahexaenoic acid, and icosapentaenoic acid were key factors for the differences of these pathways. Conclusion: This study demonstrated that the pathways of arginine biosynthesis metabolism, linoleic acid metabolism, alanine, aspartate, and glutamate metabolism, as well as d-glutamine and d-glutamate metabolism, were dysregulated in DR patients of the Asian population. Increased levels of glutamate, aspartate, glutamine, N-acetyl-l-glutamate, and N-acetyl-l-aspartate and decreased levels of dihomo-gamma-linolenate, docosahexaenoic, and icosapentaenoic were considered as the metabolic profile that could distinguish PDR from NPDR in Asians. Phosphatidylcholine and 13-PHODE were identified as two major novel metabolite markers in advanced stages of DR in our study.

Potential value of lncRNAs as a biomarker for proliferative diabetic retinopathy

OBJECTIVES

To investigate the differences in lncRNAs expression in whole blood between diabetic retinopathy (DR) patients and healthy subjects, and to evaluate the potential value of lncRNAs as a diagnostic biomarker for proliferative diabetic retinopathy (PDR).

METHODS

A series of 34 PDR patients, 34 patients with non-proliferative DR (NPDR) and 34 healthy participants were enroled. Differentially expressed lncRNAs were demonstrated using high-throughput sequencing and validated using qRT-PCR. Gene Ontology (GO) was performed to explore the possible biological function of the differentially expressed lncRNAs. lncRNA/mRNA coexpression network was built to determine the targets of differentially expressed lncRNAs. Receiver operating characteristic (ROC) analysis was utilized to evaluate the diagnostic value of lncRNAs for PDR.

RESULTS

We identified 175 and 179 differentially expressed lncRNAs in PDR patients compared with control samples and NPDR patients, respectively. GO analysis showed that the various metabolic processes were possibly influenced by these dysregulated lncRNAs. Using the differently expressed lncRNAs data, we further identified 82 overlapping lncRNAs in PDR patients with NPDR and control subjects. Part of these overlapping lncRNAs was significantly correlated with nuclear factor kappa B (NF-κB) and Wnt signal pathways. ROC curves were constructed for two upregulated lncRNAs and the ROC analysis indicated that both of them had potential diagnostic value and could distinguish PDR from control subjects and NPDR patients.

CONCLUSIONS

LncRNAs expression was altered in PDR patients compared with NPDR and control subjects. Moreover, it provides a resource that lncRNAs might be novel diagnostic and prognostic biomarker for PDR.

Proteomic profiling and correlations with clinical features reveal biomarkers indicative of diabetic retinopathy with diabetic kidney disease

Diabetic retinopathy (DR) and diabetic kidney disease (DKD) are complications of diabetes and place serious health and economic burdens on society. However, the identification and characterization of early biomarkers for DKD, especially for nonproliferative DR (NPDR) patients with DKD, are still needed. This study aimed to demonstrate the plasma proteomic profiles of NPDR+DKD and NPDR patients and identify potential biomarkers for early diagnosis of DKD. Fifteen plasma samples from the NPDR group and nine from the NPDR+DKD group were analyzed by LC-MS/MS to identify the differentially expressed proteins between the two groups. Functional enrichment, protein-protein interaction and clinical feature correlation analyses revealed the target protein candidates, which were verified using ELISA and receiver operating characteristic (ROC) analysis. In total, 410 proteins were detected in plasma; 15 were significantly upregulated and 7 were downregulated in the NPDR+DKD group. Bioinformatics analysis suggested that DKD is closely related to cell adhesion and immunity pathways. β-2-Microglobulin (B2M) and vimentin (VIM) were upregulated in NPDR+DKD, enriched as hub proteins and strongly correlated with clinical features. ELISA showed that B2M (p<0.001) and VIM (p<0.0001) were significantly upregulated in NPDR+DKD compared with NPDR. In ROC analysis, B2M and VIM could distinguish DKD from NPDR with area under the curve values of 0.9000 (p < 0.0001) and 0.9950. Our proteomic study revealed alterations in the proteomic profile and identified VIM and B2M as early biomarkers of DKD, laying the foundation for the prevention, diagnosis and treatment of DKD.

Autophagy is required for the promoting effect of angiogenic factor with G patch domain and forkhead-associated domain 1 (AGGF1) in retinal angiogenesis

OBJECTIVE

To investigate the effect of angiogenic factor with G patch domain and forkhead-associated domain 1 (AGGF1) on retinal angiogenesis in ischemic retinopathy and its association with autophagy.

METHODS

RF/6A cells were divided into the control group, hypoxia group and high-glucose group, and the expression of AGGF1 in cells was detected. C57BL/6 J mice were divided into the control group, oxygen-induced retinopathy (OIR) group and diabetic retinopathy (DR) group, and AGGF1 expression in the retina was observed. RF/6A cells were then divided into the control group and different AGGF1 concentration groups, and the expression of autophagy marker, LC3 was detected. Then, RF/6A cells were divided into the control group, AGGF1 group, 3-methyladenine (3-MA, an early autophagy inhibitor) + AGGF1 group and chloroquine (CQ, a late autophagy inhibitor) + AGGF1 group, and the expression of autophagy markers, LC3 and p62, autophagic flux, as well as was key signaling pathway proteins in autophagy, PI3K, AKT, and mTOR was detected. Finally, the cell proliferation, migration and tube formation were detected in the four groups.

RESULTS

AGGF1 expression in RF/6A cells and in the retinas of OIR and DR mouse model was found to be increased in the state of hypoxic and high glucose condition. AGGF1 treatment led to increased expressions of LC3 and decreased p62; therby induced autophagic flux, and the phosphorylation of PI3K, AKT and mTOR was down-regulated in RF/6A cells. When autophagy was inhibited by 3-MA or CQ, confirmed by corresponding changes of these indicators of autophagy, cellular proliferation, migration and tube formation of RF/6A cells were weakened by AGGF1 treatment when compared with that of AGGF1 treatment alone.

CONCLUSION

This study experimentally revealed that AGGF1 activates autophagy to promote angiogenesis for ischemic retinopathy and inhibition of PI3K/AKT/mTOR pathway may be involved in the activation of autophagy by AGGF1.

Serum superoxide dismutase activity: a sensitive, convenient, and economical indicator associated with the prevalence of chronic type 2 diabetic complications, especially in men

To investigate the relationship between serum superoxide dismutase (SOD) activity and the presence of chronic complications in patients with type 2 diabetes mellitus (T2DM). We conducted a retrospective cross-sectional study in patients with T2DM. They were assigned to three groups (Q1, Q2, and Q3) by SOD levels in both sexes. Clinical characteristics, cardiovascular disease, diabetic retinopathy, nephropathy, and peripheral neuropathy were compared. The relationship between the SOD and the prevalence of chronic complications was analyzed by binary logistic regression. Statistical analysis was performed in SPSS 26.0 (SPSS Inc., Chicago, IL). A total of 645 T2DM patients (401 men and 244 women) with complete data for SOD and medical records of complications were included. In men, patients in the Q1 group (lowest serum SOD activity) had the highest prevalence of diabetes with atherosclerosis (AS) (p<.001), DN (p=.029), and DPN (p=.001). In comparison, only DN was found to have the highest prevalence in the Q1 group in women (p=.010). In the multivariate analysis, patients in the Q1 group had a 3.0-, 1.6-, 1.9-, and 2.4-fold risk for the prevalence of AS, DR, DN, and DPN, respectively, compared with the Q3 group. In women, a 7.0-fold risk for the prevalence of DN in the Q1 group was found compared with the Q3 group. After adjusting for the age, duration of T2DM, body mass index, pulse pressure, alanine transaminase, clearance of creatinine, triglyceride, glycosylated hemoglobin, and fasting C-peptide in the models, the differences found in both men and women persisted. SOD activity is related to cardiovascular and microvascular diseases in men and the prevalence of diabetic nephropathy in women in T2DM.

Burden of vision loss due to diabetic retinopathy in China from 1990 to 2017: findings from the global burden of disease study

PURPOSE

To conduct a detailed analysis on the burden of vision loss due to diabetic retinopathy (DR) by year, age and gender in China from 1990 to 2017.

METHODS

This is a between-country, retrospective, comparative burden-of-disease study. Prevalence and Years Lived with Disability (YLDs) data caused by DR in China and relative territories were extracted from the Global Burden of Disease (GBD) study 2017 to observe the changing trends of vision loss.

RESULTS

Prevalence and YLDs of DR in China increased significantly from 1990 to 2017. The age-standardized prevalence and YLDs rate witnessed a slowly declining trend recently. Higher prevalence and YLDs were observed in female subjects in the past three decades. Middle-aged and elderly people suffered from a higher burden of DR-induced vision loss. The total age-standardized prevalence rate of China in 1990 (17.68) and 2017 (21.88) was lower than that of other seven neighbouring countries. In 2017, moderate vision loss (MVL) (17.19) accounted for the largest proportion in China. The all-age YLDs of DR showed the second-highest increase (150.26%) while the age-standardized YLDs rate showed the third-highest increase (14.91%) among fifteen common causes of vision impairment (VI) from 1990 to 2017. China ranked 3rd among G20 countries in terms of all-age YLDs while ranked 18th in age-standardized YLDs rate in 2017.

CONCLUSIONS

In the past three decades, the prevalence and YLDs due to DR in China have improved in both genders. This study highlights the importance of prevention for DR, especially for women and the elderly.

Intravitreal aflibercept partially reverses severe non-proliferative diabetic retinopathy in treatment-naïve patients

Objective

To evaluate whether diabetic retinopathy can be reversed after aflibercept, based on improvements in diabetic macular edema, hard exudates (HEs) of the posterior pole, and retinal microaneurysms (MAs).

Methods

This was a single-center retrospective study of 30 patients (34 eyes) with severe non-proliferative diabetic retinopathy (NPDR) who were treated between August and October 2018. Best-corrected visual acuity (BCVA), central foveal thickness (CFT), area of HEs, and number of MAs were compared before and after treatment.

Results

The mean patient age was 61.4 ± 7.1 years; 14 patients (46.7%) were men. The mean number of injections per patient was 3.5 ± 0.5. The time between the last injection and the last follow-up was 82 days (range, 78–110 days). Six months after the first intravitreal injection, significant improvement was observed in BCVA (from 0.70 ± 0.18 to 0.42 ± 0.19 logMAR), CFT (from 377.17 ± 60.41 to 261.21 ± 31.50 µm), and number of MAs (from 182.2 ± 77.4 to 101.5 ± 59.6). Observations over 6 months after the first intravitreal injection showed a statistically significant reduction in the area of HEs (P = 0.007). No adverse events occurred during the treatment period.

Conclusion

Diabetic retinopathy might be partially reversed by aflibercept treatment, as indicated by BCVA, CFT, number of MAs, and area of HEs.

A Diagnostic Model for Screening Diabetic Retinopathy Using the Hand-Held Electroretinogram Device RETeval

PURPOSE

To construct a proper model to screen for diabetic retinopathy (DR) with the RETeval.

METHOD

This was a cross-sectional study. Two hundred thirty-two diabetic patients and seventy controls were recruited. The DR risk assessment protocol was performed to obtain subjects' DR risk score using the RETeval. Afterwards, the receiver operating characteristic (ROC) curve was used to determine the best cutoff for diagnosing DR. Random forest and decision tree models were constructed.

RESULTS

With increasing DR severity, the DR score gradually increased. When the DR score was used to diagnose DR, the ROC curve had an area under the curve of 0.881 (95% confidence interval: 0.836-0.927, P < 0.001), with a best cutoff value of 22.95, a sensitivity of 74.3% (95 CI: 66.0%~82.6%), and a specificity of 90.6% (95 CI: 83.7% ~94.8%). The top four risk factors selected by the random forest were used to construct the decision tree for diagnosing DR, which had a sensitivity of 93.3% (95% CI: 86.3%~97.0%) and a specificity of 80.3% (95% CI: 72.1% ~86.6%).

CONCLUSIONS

The DR risk assessment protocol combined with the decision tree model was innovatively used to evaluate the risk of DR, improving the sensitivity of diagnosis, which makes this method more suitable than the current protocol for DR screening.

An Interpretable Ensemble Deep Learning Model for Diabetic Retinopathy Disease Classification

Diabetic retinopathy (DR) is one kind of eye disease that is caused by overtime diabetes. Lots of patients around the world suffered from DR which may bring about blindness. Early detection of DR is a rigid quest which can remind the DR patients to seek corresponding treatments in time. This paper presents an automatic image-level DR detection system using multiple well-trained deep learning models. Besides, several deep learning models are integrated using the Adaboost algorithm in order to reduce the bias of each single model. To explain the results of DR detection, this paper provides weighted class activation maps (CAMs) that can illustrate the suspected position of lesions. In the pre-processing stage, eight image transformation ways are also introduced to help augment the diversity of fundus images. Experiments demonstrate that the method proposed by this paper has stronger robustness and acquires more excellent performance than that of individual deep learning model.