Prevalence and risk factors of diabetic retinopathy in patients with type 2 diabetes in Shanghai

Gut microbiota induced abnormal amino acids and their correlation with diabetic retinopathy

AIM

To explore the correlation of gut microbiota and the metabolites with the progression of diabetic retinopathy (DR) and provide a novel strategy to elucidate the pathological mechanism of DR.

METHODS

The fecal samples from 32 type 2 diabetes patients with proliferative retinopathy (PDR), 23 with non-proliferative retinopathy (NPDR), 27 without retinopathy (DM), and 29 from the sex-, age- and BMI- matched healthy controls (29 HC) were analyzed by 16S rDNA gene sequencing. Sixty fecal samples from PDR, DM, and HC groups were assayed by untargeted metabolomics. Fecal metabolites were measured using liquid chromatography-mass spectrometry (LC-MS) analysis. Associations between gut microbiota and fecal metabolites were analyzed.

RESULTS

A cluster of 2 microbiome and 12 metabolites accompanied with the severity of DR, and the close correlation of the disease progression with PDR-related microbiome and metabolites were found. To be specific, the structure of gut microbiota differed in four groups. Diversity and richness of gut microbiota were significantly lower in PDR and NPDR groups, than those in DM and HC groups. A cluster of microbiome enriched in PDR group, including Pseudomonas, Ruminococcaceae-UCG-002, Ruminococcaceae-UCG-005, Christensenellaceae-R-7, was observed. Functional analysis showed that the glucose and nicotinate degradations were significantly higher in PDR group than those in HC group. Arginine, serine, ornithine, and arachidonic acid were significantly enriched in PDR group, while proline was enriched in HC group. Functional analysis illustrated that arginine biosynthesis, lysine degradation, histidine catabolism, central carbon catabolism in cancer, D-arginine and D-ornithine catabolism were elevated in PDR group. Correlation analysis revealed that Ruminococcaceae-UCG-002 and Christensenellaceae-R-7 were positively associated with L-arginine, ornithine levels in fecal samples.

CONCLUSION

This study elaborates the different microbiota structure in the gut from four groups. The relative abundance of Ruminococcaceae-UCG-002 and Parabacteroides are associated with the severity of DR. Amino acid and fatty acid catabolism is especially disordered in PDR group. This may help provide a novel diagnostic parameter for DR, especially PDR.

Research progress of diabetic retinopathy and gut microecology

According to the prediction of the International Diabetes Federation, global diabetes mellitus (DM) patients will reach 783.2 million in 2045. The increasing incidence of DM has led to a global epidemic of diabetic retinopathy (DR). DR is a common microvascular complication of DM, which has a significant impact on the vision of working-age people and is one of the main causes of blindness worldwide. Substantial research has highlighted that microangiopathy and chronic low-grade inflammation are widespread in the retina of DR. Meanwhile, with the introduction of the gut-retina axis, it has also been found that DR is associated with gut microecological disorders. The disordered structure of the GM and the destruction of the gut barrier result in the release of abnormal GM flora metabolites into the blood circulation. In addition, this process induced alterations in the expression of various cytokines and proteins, which further modulate the inflammatory microenvironment, vascular damage, oxidative stress, and immune levels within the retina. Such alterations led to the development of DR. In this review, we discuss the corresponding alterations in the structure of the GM flora and its metabolites in DR, with a more detailed focus on the mechanism of gut microecology in DR. Finally, we summarize the potential therapeutic approaches of DM/DR, mainly regulating the disturbed gut microecology to restore the homeostatic level, to provide a new perspective on the prevention, monitoring, and treatment of DR.

Risk Factors for Diabetic Retinopathy in Chinese Patients with Different Diabetes Duration: Association of C-Peptide and BUN/Cr Ratio with Type 2 Diabetic Retinopathy

Background and Aim

Controlling the risk factors was the most effective strategy to prevent diabetic retinopathy (DR). This study aimed to recognize the risk factors of DR, and explores whether the effect of those factors is modified by diabetes mellitus (DM) duration.

Methods

A total of 1058 DM patients with information about DR assessment were included. DR was measured by a complete ophthalmic examination and was classified as having one or more distinct microaneurysms in the eyes. Data from the lab and clinical factors were gathered. Multivariate logistic analysis was used to examine the risk factors, and the best-fitting model was selected by a backward stepwise based on A1C.

Results

In the current study, 274 (25.9%) patients developed DR. In the entire subjects, baseline age, the level of C-peptide, and urinary creatinine were all presented as protective effects of DR, whose odds ratios (ORs) and 95% confidence intervals (CIs) were 0.79 (0.62, 0.99), 0.75 (0.61, 0.91), and 0.70 (0.52, 0.93), respectively. Conversely, systolic pressure (SBP), urinary albumin, and BUN/Cr ratio were the important risk factors for DR with ORs (95% CIs) 1.21 (1.01, 1.46), 1.55 (1.30, 1.84), and 1.33 (1.11, 1.59), respectively. In stratification analysis, females with higher SBP would be more likely to develop DR in the short-duration group, while C-peptide and urinary creatinine showed protective effects in the long-duration group. BUN/Cr ratio all presented as a risk factor, with ORs 1.38 (p = 0.041) and 1.33 (p = 0.014) in short- and long-duration groups, respectively.

Conclusion

Although renal functions presented a significant association with DR in all DM patients, the risk factors of DR varied widely in different disease-duration subjects. Target strategies to prevent DR should be put forward individually, considering the patient's DM duration. Improving the BUN/Cr ratio may be beneficial to delaying DR.

Correlation between diabetic retinopathy and Helicobacter pylori infection: a cross-sectional retrospective study

AIM

To explore the correlation between diabetic retinopathy (DR) and Helicobacter pylori (Hp) infection, based on data from a physical examination population.

METHODS

This cross-sectional retrospective analysis included data of 73 824 health examination participants from December 2018 to December 2019. Participants were divided into the diabetic group and non-diabetic group, non-diabetic retinopathy (NDR) group, non-proliferative diabetic retinopathy (NPDR) group, proliferative diabetic retinopathy (PDR) group, and Hp infection group. Gender, age, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting plasma glucose (FPG), glycated hemoglobin A1c (HbA1c), triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and Hp data were recorded to compare the degree of DR lesions and Hp infection. Logistic regression analysis was used to evaluate the correlation between DR and Hp infection.

RESULTS

There was a statistically significant difference between the diabetic and non-diabetic group (χ2=94.17, P<0.0001). Logistic regression analysis showed that male sex, age, BMI, SBP, TG, LDL-C, and Hp infection were independent risk factors for DR. There was no correlation between the degree of DR lesions and Hp infection (ρ=-0.00339, P=0.7753). Age [odds ratio (OR)=1.035, 95%CI: 1.024, 1.046, P<0.0001] and SBP (OR=1.009, 95%CI: 1.004, 1.015, P=0.0013) were independent risk factors for the degree of DR.

CONCLUSION

There is a significant correlation between DR and Hp infection in the physical examination population. Hp infection is a risk factor for DR, and there is no significant difference between Hp infection and DR of different pathological degrees. Actively eradicating Hp may be of help to prevent DR.

Prevalence and risk factors of diabetic retinopathy among Chinese adults with type 2 diabetes in a suburb of Shanghai, China

Background

To investigate the prevalence and risk factors of diabetic retinopathy (DR) in a Chinese population with type 2 diabetes mellitus (T2DM) in a suburb (Qingpu) of Shanghai, China.

Methods

A population-based cross-sectional study. A total of 7462 residents with T2DM in Qingpu were enrolled according to the resident health archives from January 2020 to December 2020. Blood and urine samples of the subjects were collected. Disc- and macula-centred retinal images were taken to assess DR. SPSS was used to analyse and investigate the prevalence and risk factors of DR.

Results

The fundus images of 6380 (85.5%) subjects were of sufficiently good quality for grading. The average (range) age of 6380 subjects was 63.46±7.77 (28–92) years. Six hundred forty-four subjects were diagnosed with DR. The prevalence of DR was 10.1% (95% CI 9.4%-10.8%), with mild, moderate, and severe non-proliferative retinopathy and proliferative retinopathy being 2.1%, 6.3%, 1.3% and 0.4%, respectively. The prevalence of bilateral DR was 6.5%. Higher T2DM duration (OR, 1.057), fasting plasma glucose (OR, 1.063), glycated hemoglobinA1c (OR, 1.269), urea nitrogen (OR, 1.059), and urinary albumin (OR, 1.001) were associated with the higher DR prevalence.

Conclusion

The prevalence of DR among Chinese adults with T2DM in Qingpu was 10.1%, in which non-proliferative DR was more common. Higher fasting plasma glucose and glycated hemoglobinA1c are well-known risk factors of DR, consistent with the findings in our study. Our study didn’t find the risk between lipid indicators and DR. However, several renal function indicators, like higher urea nitrogen and urinary albumin, were risk factors for DR in this study. Appropriate diagnosis and intervention should be taken in time to prevent and control DR development.

Association between Transcription Factor 7-Like 2 C/T Polymorphism and Diabetic Retinopathy Risk: A Meta-Analysis

BACKGROUND

Previous studies have suggested a close association between transcription factor 7-like 2 (TCF7L2) polymorphisms and diabetic retinopathy (DR) susceptibility. However, the published results were inconsistent. This meta-analysis was conducted to review and examine the relationship between TCF7L2 rs7903146 C/T polymorphism and DR risk.

MATERIALS AND METHODS

Online databases were searched, and the related studies were identified in this meta-analysis. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated to examine the statistical power. Moreover, heterogeneity test, sensitivity accumulative analysis, and publication bias were conducted to measure the statistical effect.

RESULT

6 studies involving 12,982 subjects were included in this meta-analysis to assess the association between rs7903146 C/T polymorphism and DR susceptibility. The synthetic results indicated that the mutation of rs7903146 C/T polymorphism maybe accompanied with an increased risk for DR (T vs. C: OR = 1.26, 95% CI = 1.00-1.60, p = 0.05, I2 = 83.5%; TT vs. CC: OR = 1.79, 95% CI = 1.12-2.86, p = 0.02, I2 = 80.2%; TT vs. CC + CT: OR = 1.62, 95% CI = 1.38-1.92, p < 0.01, I2 = 32.3%). Moreover, the subgroup analysis also demonstrated an increasing risk for DR with T mutations in Caucasian descendants.

CONCLUSION

The current evidences of meta-analysis suggested that the TCF7L2 rs7903146 C/T polymorphism might play an important role in DR susceptibility.

Emerging Trends and Research Foci in Artificial Intelligence for Retinal Diseases: A Bibliometric and Visualized Study (Preprint)

Background

Patients with retinal diseases may exhibit serious complications that cause severe visual impairment owing to a lack of awareness of retinal diseases and limited medical resources. Understanding how artificial intelligence (AI) is used to make predictions and perform relevant analyses is a very active area of research on retinal diseases. In this study, the relevant Science Citation Index (SCI) literature on the AI of retinal diseases published from 2012 to 2021 was integrated and analyzed.

Objective

The aim of this study was to gain insights into the overall application of AI technology to the research of retinal diseases from set time and space dimensions.

Methods

Citation data downloaded from the Web of Science Core Collection database for AI in retinal disease publications from January 1, 2012, to December 31, 2021, were considered for this analysis. Information retrieval was analyzed using the online analysis platforms of literature metrology: Bibliometrc, CiteSpace V, and VOSviewer.

Results

A total of 197 institutions from 86 countries contributed to relevant publications; China had the largest number and researchers from University College London had the highest H-index. The reference clusters of SCI papers were clustered into 12 categories. “Deep learning” was the cluster with the widest range of cocited references. The burst keywords represented the research frontiers in 2018-2021, which were “eye disease” and “enhancement.”

Conclusions

This study provides a systematic analysis method on the literature regarding AI in retinal diseases. Bibliometric analysis enabled obtaining results that were objective and comprehensive. In the future, high-quality retinal image–forming AI technology with strong stability and clinical applicability will continue to be encouraged.

Prevalence of and risk factors for diabetic retinopathy in residents with different types of abnormal glucose metabolism with or without hypertension: A suburban community-based cross-sectional study

AIMS

The present study examined the prevalence and risk factors for diabetic retinopathy (DR) in residents with abnormal glucose metabolism in a community.

METHODS

6029 subjects were included and underwent standardized interviews and comprehensive examinations. Residents with diabetes were divided into nondiabetic retinopathy (NDR) and DR groups and non-hypertension and hypertension groups. Unconditional multivariate logistic regression models were used to analyze the risk factors for DR in different groups.

RESULTS

The prevalence of DR in diabetes was 9.9%, and the prevalence of retinopathy, which also has the typical signs of DRs, such as retinal microaneurysms, in prediabetes and normal glucose tolerance was 5.2% and 5.3%, respectively. An elevated waist-to-hip ratio (WHR) (female≥0.85, male≥0.9)[OR 1.683, 95% CI (1.016, 2.790)], systolic blood pressure (SBP)≥140 mmHg [OR 1.875, 95% CI (1.158, 3.034)], elevated HbA1c [OR 1.410, 95% CI (1.220, 1.629)], HbA1c ≥6.5% [OR 2.149, 95% CI (1.320, 3.498)], antidiabetic drug use [OR 3.798, 95% CI (2.209, 6.529)], elevated fasting blood glucose [OR 1.176, 95% CI (1.072, 1.289)], elevated postprandial blood glucose [OR 1.090, 95% CI (1.033, 1.150)] and nonspecific ST-T segment changes on electrocardiography [OR 2.555, 95% CI (1.556, 4.196)] were risk factors for DR. Duration of diabetes [OR 1.206, 95% CI (1.028, 1.415)], elevated WHR [OR 3.796, 95% CI (1.144, 12.603)], elevated waist circumference [OR 6.874, 95% CI (1.403, 33.665)], elevated HbA1c [OR 1.435, 95% CI (1.046, 1.970)], HbA1c ≥6.5% [OR 6.850, 95% CI (1.771, 26.501)], and concurrent metabolic syndrome [OR 3.975, 95% CI (1.144, 13.815)] were risk factors for DR in diabetes without hypertension, and elevated HbA1c [OR 1.395, 95% CI (1.183, 1.645)], HbA1c ≥6.5% [OR 1.745, 95% CI (1.027, 2.966)], use of antidiabetic drugs [OR 4.781, 95% CI (2.624, 8.711)], elevated fasting blood glucose [OR 1.146, 95% CI (1.034, 1.270)], elevated postprandial blood glucose [OR 1.083, 95% CI (1.020, 1.151)], and nonspecific ST-T segment changes on electrocardiography [OR 2.616, 95% CI (1.531, 4.469)] were risk factors for DR in diabetes with hypertension.

CONCLUSION

Retinopathy was found in subjects with normal glucose tolerance and prediabetes. There were differences in risk factors for DR in diabetic patients with and without hypertension.