The Effect of Diet and Lifestyle on the Course of Diabetic Retinopathy-A Review of the Literature

Gentiopicroside ameliorates glucose and lipid metabolism in T2DM via targeting FGFR1

BACKGROUND

The suppression of the fibroblast growth factor 21/fibroblast growth factor receptor 1 (FGF21/FGFR1) signaling pathway is considered as a vital factor in the type 2 diabetes mellitus (T2DM) progression. Our previous study showed that gentiopicroside (GPS), the main active compound present in Gentiana macrophylla Pall., has the capacity to control disorders related to glucose and lipid metabolism in individuals with T2DM. Nevertheless, the specific mechanism remains unclear.

PURPOSE

In light of the fact that the PharmMapper database suggests FGFR1 as the target of GPS, our investigation aims to determine if GPS can enhance glucose and lipid metabolism issues in T2DM by modulating the FGF21/FGFR1 signaling pathway.

METHODS

In this study, we used palmitic acid (PA)-induced HepG2 cells and db/db mice to investigate the function and mechanism of GPS in the FGF21/FGFR1 signaling pathway. To examine the interaction between GPS and FGFR1, researchers performed Cellular Thermal Shift Assay (CETSA) and Surface Plasmon Resonance (SPR) analysis.

RESULTS

The results suggest that GPS activates the traditional metabolic pathways, including PI3K/AKT and AMPK, which are the subsequent stages of the FGF21/FGFR1 pathway. This activation leads to the enhancement of glucose and lipid metabolism issues in PA-treated HepG2 cells and db/db mice. Furthermore, the depletion of FGFR1 has been noticed to oppose the stimulation of PI3K/AKT and AMPK pathways by GPS in HepG2 cells subjected to PA. Notability, our research affirms that GPS binds directly to FGFR1, hindering the ubiquitinated degradation of FGFR1 by neural precursor cells expressing developmentally decreased protein 4 (NEDD4) and ultimately promoting FGF21 signal transduction.

CONCLUSION

This study demonstrates that GPS targeting FGFR1 activates the PI3K/AKT and AMPK pathways, which is an important mechanism for its treatment of T2DM.

Epigenetics research in eye diseases: a bibliometric analysis from 2000 to 2023

CLINICAL RELEVANCE

A bibliometric analysis is a quantitative study that utilises methods such as citation analysis to evaluate research performance. A bibliometric analysis could provide a valuable reference for ophthalmic researchers to understand the trends in epigenetics research.

BACKGROUND

The number of studies on epigenetics in eye diseases has exceeded 5,000, but the progress and scope of epigenetic research on eye diseases remain unclear. The study aimed to bibliometrically analyse epigenetic research conducted in eye diseases.

METHODS

Studies concerning epigenetic research on eye diseases from 2000-2023 were searched using the Web of Science Core Collection. Following this, the included studies were analysed for citations, journals, keywords, authors, and countries, using the Bibliometrix package in R Studio.

RESULTS

In total, 3758 studies were included in the analysis, including 3099 original articles, 599 reviews, 11 editorials, and 49 early access articles. Investigative Ophthalmology & Visual Science was the most published journal with 185 articles, and Proceedings of the National Academy of Sciences of the United States of America was the most cited journal, with 8727 citations. The journal with the highest h-index was Oncogene (h-index = 38).Renu A Kowluru from the Kresge Eye Institute, Wayne State University, Detroit, USA, had the most citations with 1,690 and the highest h-index (h-index = 23). China and the USA were the countries with the highest number of publications (1739) and total citations (40533), respectively. Furthermore, from 2000-2023, the top five frequent research topics were diabetic retinopathy, 522; microribonucleic acid, 469; retinoblastoma, 370; apoptosis, 268; and epigenetics, 206.

CONCLUSIONS

The results of this bibliometric study provide the current status and trends of epigenetic research in eye diseases and will help researchers identify areas of current interest in the field, which should help highlight new research directions.

Associations Between Life's Essential 8 and Major Ocular Diseases in the American Middle-Aged and Elderly Population

PURPOSE

To explore the correlation between cardiovascular health (CVH) and ocular diseases, given their shared risk factors and biological mechanisms, this study utilizes the newly updated Life's Essential 8 (LE8) algorithm.

DESIGN

A cross-sectional study.

METHODS

This analysis, conducted from February 15 to April 1, 2024, in Changchun, includes data from 4146 participants aged 40 and above, drawn from the National Health and Nutrition Examination Survey database (2005-2008). It covers information on visual health status, dietary habits through interviews, and professional ophthalmological examinations. Participants' CVH status was assessed using the LE8 algorithm, and relationships with major ocular diseases such as retinopathy, cataracts, diabetic retinopathy, glaucoma, and age-related macular degeneration were explored through weighted logistic regression analysis, restricted cubic splines, stratified analysis, and sensitivity analysis.

RESULTS

After multivariable adjustment, lower LE8 scores showed a significant positive relationship with any ocular disease (odds ratio [OR]: 2.03, 95% confidence interval [CI]: 1.39-2.96, P = .001), any objectively determined ocular disease (OR: 2.24, 95% CI: 1.48-3.38, P < .001), retinopathy (OR: 2.88, 95% CI: 1.89-4.41, P < .001), diabetic retinopathy (OR: 10.23, 95% CI: 3.11-33.61, P < .001), and glaucoma (OR: 2.76, 95% CI: 1.47-5.21, P = .003), with all trends significant (all P < .01). Additionally, lower scores in the behavioral subdomain were significantly correlated with an elevated risk of cataracts (OR: 1.45, 95% CI: 1.03-2.04). Subgroup analyses revealed more pronounced negative correlations between LE8 and retinopathy among females and those suffering from chronic kidney disease.

CONCLUSIONS

A low CVH score was linked to an increased likelihood of ocular diseases in a US-populated-based study. This correlation supports the potential benefits of enhancing cardiovascular wellness to mitigate the development of ocular conditions.

Are Hyperglycemia-Induced Changes in the Retina Associated with Diabetes-Correlated Changes in the Brain? A Review from Zebrafish and Rodent Type 2 Diabetes Models

Diabetes is prevalent worldwide, with >90% of the cases identified as Type 2 diabetes. High blood sugar (hyperglycemia) is the hallmark symptom of diabetes, with prolonged and uncontrolled levels contributing to subsequent complications. Animal models have been used to study these complications, which include retinopathy, nephropathy, and peripheral neuropathy. More recent studies have focused on cognitive behaviors due to the increased risk of dementia/cognitive deficits that are reported to occur in older Type 2 diabetic patients. In this review, we collate the data reported from specific animal models (i.e., mouse, rat, zebrafish) that have been examined for changes in both retina/vision (retinopathy) and brain/cognition, including db/db mice, Goto-Kakizaki rats, Zucker Diabetic Fatty rats, high-fat diet-fed rodents and zebrafish, and hyperglycemic zebrafish induced by glucose immersion. These models were selected because rodents are widely recognized as established models for studying diabetic complications, while zebrafish represent a newer model in this field. Our goal is to (1) summarize the published findings relevant to these models, (2) identify similarities in cellular mechanisms underlying the disease progression that occur in both tissues, and (3) address the hypothesis that hyperglycemic-induced changes in retina precede or predict later complications in brain.

Genetic Association between Lipid-Regulating Drug Targets and Diabetic Retinopathy: A Drug Target Mendelian Randomization Study

Background

Diabetic retinopathy (DR) is a diabetic microvascular complication and a leading cause of vision loss. However, there is a lack of effective strategies to reduce the risk of DR currently. The present study is aimed at assessing the causal effect of lipid-regulating targets on DR risk using a two-sample Mendelian randomization (MR) study.

Method

Genetic variants within or near drug target genes, including eight lipid-regulating targets for LDL-C (HMGCR, PCSK9, and NPC1L1), HDL-C (CETP, SCARB1, and PPARG), and TG (PPARA and LPL), were selected as exposures. The exposure data were obtained from the IEU OpenGWAS project. The outcome dataset related to DR was obtained from the FinnGen research project. Inverse-variance-weighted MR (IVW-MR) was used to calculate the effect estimates by each target. Sensitivity analyses were performed to verify the robustness of the results.

Results

There was suggestive evidence that PCSK9-mediated LDL-C levels were positively associated with DR, with OR (95% CI) of 1.34 (1.02-1.77). No significant association was found between the expression of HMGCR- and NPC1L1-mediated LDL-C levels; CETP-, SCARB1-, and PPARG-mediated HDL-C levels; PPARA- and LPL-mediated TG levels; and DR risk.

Conclusions

This is the first study to reveal a genetically causal relationship between lipid-regulating drug targets and DR risk. PCSK9-mediated LDL-C levels maybe positively associated with DR risk at the genetic level. This study provides suggestive evidence that PCSK9 inhibition may reduce the risk of DR.

Effect of High-Sucrose Diet on the Occurrence and Progression of Diabetic Retinopathy and Dietary Modification Strategies

As the most serious of the many worse new pathological changes caused by diabetes, there are many risk factors for the occurrence and development of diabetic retinopathy (DR). They mainly include hyperglycemia, hypertension, hyperlipidemia and so on. Among them, hyperglycemia is the most critical cause, and plays a vital role in the pathological changes of DR. High-sucrose diets (HSDs) lead to elevated blood glucose levels in vivo, which, through oxidative stress, inflammation, the production of advanced glycation end products (AGEs) and vascular endothelial growth factor (VEGF), cause plenty of pathological damages to the retina and ultimately bring about loss of vision. The existing therapies for DR primarily target the terminal stage of the disease, when irreversible visual impairment has appeared. Therefore, early prevention is particularly critical. The early prevention of DR-related vision loss requires adjustments to dietary habits, mainly by reducing sugar intake. This article primarily discusses the risk factors, pathophysiological processes and molecular mechanisms associated with the development of DR caused by HSDs. It aims to raise awareness of the crucial role of diet in the occurrence and progression of DR, promote timely changes in dietary habits, prevent vision loss and improve the quality of life. The aim is to make people aware of the importance of diet in the occurrence and progression of DR. According to the dietary modification strategies that we give, patients can change their poor eating habits in a timely manner to avoid theoretically avoidable retinopathy and obtain an excellent prognosis.

Understanding the Clinical Relationship Between Diabetic Retinopathy, Nephropathy, and Neuropathy: A Comprehensive Review

Diabetic retinopathy, nephropathy, and neuropathy are significant microvascular complications of diabetes mellitus, contributing to substantial morbidity and mortality worldwide. This comprehensive review examines the clinical relationship between these complications, focusing on shared pathophysiological mechanisms, bidirectional relationships, and implications for patient management. The review highlights the importance of understanding the interconnected nature of diabetic complications and adopting a holistic approach to diabetes care. Insights gleaned from this review underscore the necessity for early detection, timely intervention, and integrated care models involving collaboration among healthcare professionals. Furthermore, the review emphasizes the need for continued research to elucidate underlying mechanisms, identify novel therapeutic targets, and assess the efficacy of integrated care strategies in improving patient outcomes. By fostering interdisciplinary collaboration and knowledge exchange, future research endeavors hold the potential to advance our understanding and management of diabetic complications, ultimately enhancing patient care and quality of life.

Trimethylamine N-oxide aggravates vascular permeability and endothelial cell dysfunction under diabetic condition: in vitro and in vivo study

AIM

To provide the direct evidence for the crucial role of trimethylamine N-oxide (TMAO) in vascular permeability and endothelial cell dysfunction under diabetic condition.

METHODS

The role of TMAO on the in vitro biological effect of human retinal microvascular endothelial cells (HRMEC) under high glucose conditions was tested by a cell counting kit, wound healing, a transwell and a tube formation assay. The inflammation-related gene expression affected by TMAO was tested by real-time polymerase chain reaction (RT-PCR). The expression of the cell junction was measured by Western blotting (WB) and immunofluorescence staining. In addition, two groups of rat models, diabetic and non-diabetic, were fed with normal or 0.1% TMAO for 16wk, and their plasma levels of TMAO, vascular endothelial growth factor (VEGF), interleukin (IL)-6 and tumor necrosis factor (TNF)-α were tested. The vascular permeability of rat retinas was measured using FITC-Dextran, and the expression of zonula occludens (ZO)-1 and claudin-5 in rat retinas was detected by WB or immunofluorescence staining.

RESULTS

TMAO administration significantly increased the cell proliferation, migration, and tube formation of primary HRMEC either in normal or high-glucose conditions. RT-PCR showed elevated inflammation-related gene expression of HRMEC under TMAO stimulation, while WB or immunofluorescence staining indicated decreased cell junction ZO-1 and occludin expression after high-glucose and TMAO treatment. Diabetic rats showed higher plasma levels of TMAO as well as retinal vascular leakage, which were even higher in TMAO-feeding diabetic rats. Furthermore, TMAO administration increased the rat plasma levels of VEGF, IL-6 and TNF-α while decreasing the retinal expression levels of ZO-1 and claudin-5.

CONCLUSION

TMAO enhances the proliferation, migration, and tube formation of HRMEC, as well as destroys their vascular integrity and tight connection. It also regulates the expression of VEGF, IL-6, and TNF-α.

Modifiable lifestyle, mental health status and diabetic retinopathy in U.S. adults aged 18-64 years with diabetes: a population-based cross-sectional study from NHANES 1999-2018

BACKGROUND

The relationship between integrated lifestyles, mental status and their impact on overall well-being has attracted considerable attention. This study aimed to evaluate the association between lifestyle factors, depression and diabetic retinopathy (DR) in adults aged 18-64 years.

METHODS

A cohort of 3482 participants diagnosed with diabetes was drawn from the National Health and Nutrition Examination Survey (NHANES) spanning the years 1999-2018. DR was defined based on self-reported diabetic retinopathy diagnoses by professional physicians, relying on Diabetes Interview Questionnaires. Subgroup analysis was employed to assess lifestyle and psychological factors between participants with DR and those without, both overall and stratified by diabetic duration. Continuous variables were analyzed using the student's t test, while weighted Rao-Scott χ2 test were employed for categorical variables to compare characteristics among the groups.

RESULTS

Of the 3482 participants, 767 were diagnosed with diabetic retinopathy, yielding a weighted DR prevalence of 20.8%. Patients with DR exhibited a higher prevalence of heavy drinking, depression, sleep deprivation, and insufficient physical activity compared to those without DR. Furthermore, multivariable logistic regression analysis revealed that sleeping less than 5 h (OR = 3.18, 95%CI: 2.04-4.95, p < 0.001) and depression (OR = 1.35, 95%CI:1.06-1.64, p = 0.025) were associated with a higher risk of DR, while moderate drinking (OR = 0.49, 95%CI: 0.32-0.75, p = 0.001) and greater physical activity (OR = 0.64, 95%CI: 0.35-0.92, p = 0.044) were identified as protective factors.

CONCLUSIONS

Adults aged 18-64 years with DR exhibited a higher prevalence of lifestyle-related risk factors and poorer mental health. These findings underscore the need for concerted efforts to promote healthy lifestyles and positive emotional well-being in this population.

Complementary Approaches to Retinal Health Focusing on Diabetic Retinopathy

Diabetes mellitus affects carbohydrate homeostasis but also influences fat and protein metabolism. Due to ophthalmic complications, it is a leading cause of blindness worldwide. The molecular pathology reveals that nuclear factor kappa B (NFκB) has a central role in the progression of diabetic retinopathy, sharing this signaling pathway with another major retinal disorder, glaucoma. Therefore, new therapeutic approaches can be elaborated to decelerate the ever-emerging "epidemics" of diabetic retinopathy and glaucoma targeting this critical node. In our review, we emphasize the role of an improvement of lifestyle in its prevention as well as the use of phytomedicals associated with evidence-based protocols. A balanced personalized therapy requires an integrative approach to be more successful for prevention and early treatment.

Establishment and health management application of a prediction model for high-risk complication combination of type 2 diabetes mellitus based on data mining

In recent years, the prevalence of T2DM has been increasing annually, in particular, the personal and socioeconomic burden caused by multiple complications has become increasingly serious. This study aimed to screen out the high-risk complication combination of T2DM through various data mining methods, establish and evaluate a risk prediction model of the complication combination in patients with T2DM. Questionnaire surveys, physical examinations, and biochemical tests were conducted on 4,937 patients with T2DM, and 810 cases of sample data with complications were retained. The high-risk complication combination was screened by association rules based on the Apriori algorithm. Risk factors were screened using the LASSO regression model, random forest model, and support vector machine. A risk prediction model was established using logistic regression analysis, and a dynamic nomogram was constructed. Receiver operating characteristic (ROC) curves, harrell's concordance index (C-Index), calibration curves, decision curve analysis (DCA), and internal validation were used to evaluate the differentiation, calibration, and clinical applicability of the models. This study found that patients with T2DM had a high-risk combination of lower extremity vasculopathy, diabetic foot, and diabetic retinopathy. Based on this, body mass index, diastolic blood pressure, total cholesterol, triglyceride, 2-hour postprandial blood glucose and blood urea nitrogen levels were screened and used for the modeling analysis. The area under the ROC curves of the internal and external validations were 0.768 (95% CI, 0.744-0.792) and 0.745 (95% CI, 0.669-0.820), respectively, and the C-index and AUC value were consistent. The calibration plots showed good calibration, and the risk threshold for DCA was 30-54%. In this study, we developed and evaluated a predictive model for the development of a high-risk complication combination while uncovering the pattern of complications in patients with T2DM. This model has a practical guiding effect on the health management of patients with T2DM in community settings.

Prevalence of diabetic retinopathy and vision-threatening diabetic retinopathy in adults with diabetes in China

The current epidemic status of diabetic retinopathy in China is unclear. A national prevalence survey of diabetic complications was conducted. 50,564 participants with gradable non-mydriatic fundus photographs were enrolled. The prevalence rates (95% confidence intervals) of diabetic retinopathy and vision-threatening diabetic retinopathy were 16.3% (15.3%-17.2%) and 3.2% (2.9%-3.5%), significantly higher in the northern than in the southern regions. The differences in prevalence between those who had not attained a given metabolic goal and those who had were more pronounced for Hemoglobin A1c than for blood pressure and low-density lipoprotein cholesterol. The participants with vision-threatening diabetic retinopathy had significantly higher proportions of visual impairment and blindness than those with non-vision-threatening diabetic retinopathy. The likelihoods of diabetic retinopathy and vision-threatening diabetic retinopathy were also associated with education levels, household income, and multiple dietary intakes. Here, we show multi-level factors associated with the presence and the severity of diabetic retinopathy.

A Mediterranean Diet May Be Protective in the Development of Diabetic Retinopathy

The Mediterranean diet is recognized as one of the healthiest available dietary patterns. This perception results from its beneficial effects on the cardiovascular system and, also, on hypertension, diabetes, and cancer compared with other diets. Its impact on the course of diabetes is assessed in the available scientific literature; however, little information is available about its impact on diabetic retinopathy. The MD is characterized mainly by the consumption of fish, seafood, foods of plant origin, and fresh fruit and vegetables. It is also recommended to consume legumes, which are a source of folic acid, magnesium, iron, and dietary fiber. High consumption of nuts and unrefined grains is also recommended in the MD. Marine fish provide polyunsaturated acids from the omega-3 group. Olive oil plays a very important role, especially olive oil obtained from mechanical pressing. Additionally, olive oil contains vitamins E, K, and polyphenols. Polyphenols, which are present in a diverse range of vegetables, fruits, and seeds, have the ability to decrease oxidative stress, inflammation, and insulin resistance. Resveratrol is naturally found in grape skins and seeds, as well as in peanuts and berries, and is a constituent of red wine. Resveratrol can inhibit increased vascular leakage and loss of pericytes and regulate the level of VEGF protein in the retina, thus inhibiting the development of DR. Consumption of fruits, vegetables, fish, and olive oil may be correlated with a lower risk of diabetic retinopathy. This paper presents the definition of the Mediterranean diet and its influence on the course of diabetes and diabetic retinopathy.

New Insights on Dietary Polyphenols for the Management of Oxidative Stress and Neuroinflammation in Diabetic Retinopathy

Diabetic retinopathy (DR) is a neurodegenerative and vascular pathology that is considered one of the leading causes of blindness worldwide, resulting from complications of advanced diabetes mellitus (DM). Current therapies consist of protocols aiming to alleviate the existing clinical signs associated with microvascular alterations limited to the advanced disease stages. In response to the low resolution and limitations of the DR treatment, there is an urgent need to develop more effective alternative therapies to optimize glycemic, vascular, and neuronal parameters, including the reduction in the cellular damage promoted by inflammation and oxidative stress. Recent evidence has shown that dietary polyphenols reduce oxidative and inflammatory parameters of various diseases by modulating multiple cell signaling pathways and gene expression, contributing to the improvement of several chronic diseases, including metabolic and neurodegenerative diseases. However, despite the growing evidence for the bioactivities of phenolic compounds, there is still a lack of data, especially from human studies, on the therapeutic potential of these substances. This review aims to comprehensively describe and clarify the effects of dietary phenolic compounds on the pathophysiological mechanisms involved in DR, especially those of oxidative and inflammatory nature, through evidence from experimental studies. Finally, the review highlights the potential of dietary phenolic compounds as a prophylactic and therapeutic strategy and the need for further clinical studies approaching the efficacy of these substances in DR management.

Elucidating glial responses to products of diabetes-associated systemic dyshomeostasis

Diabetic retinopathy (DR) is a leading cause of blindness in working age adults. DR has non-proliferative stages, characterized in part by retinal neuroinflammation and ischemia, and proliferative stages, characterized by retinal angiogenesis. Several systemic factors, including poor glycemic control, hypertension, and hyperlipidemia, increase the risk of DR progression to vision-threatening stages. Identification of cellular or molecular targets in early DR events could allow more prompt interventions pre-empting DR progression to vision-threatening stages. Glia mediate homeostasis and repair. They contribute to immune surveillance and defense, cytokine and growth factor production and secretion, ion and neurotransmitter balance, neuroprotection, and, potentially, regeneration. Therefore, it is likely that glia orchestrate events throughout the development and progression of retinopathy. Understanding glial responses to products of diabetes-associated systemic dyshomeostasis may reveal novel insights into the pathophysiology of DR and guide the development of novel therapies for this potentially blinding condition. In this article, first, we review normal glial functions and their putative roles in the development of DR. We then describe glial transcriptome alterations in response to systemic circulating factors that are upregulated in patients with diabetes and diabetes-related comorbidities; namely glucose in hyperglycemia, angiotensin II in hypertension, and the free fatty acid palmitic acid in hyperlipidemia. Finally, we discuss potential benefits and challenges associated with studying glia as targets of DR therapeutic interventions. In vitro stimulation of glia with glucose, angiotensin II and palmitic acid suggests that: 1) astrocytes may be more responsive than other glia to these products of systemic dyshomeostasis; 2) the effects of hyperglycemia on glia are likely to be largely osmotic; 3) fatty acid accumulation may compound DR pathophysiology by promoting predominantly proinflammatory and proangiogenic transcriptional alterations of macro and microglia; and 4) cell-targeted therapies may offer safer and more effective avenues for DR treatment as they may circumvent the complication of pleiotropism in retinal cell responses. Although several molecules previously implicated in DR pathophysiology are validated in this review, some less explored molecules emerge as potential therapeutic targets. Whereas much is known regarding glial cell activation, future studies characterizing the role of glia in DR and how their activation is regulated and sustained (independently or as part of retinal cell networks) may help elucidate mechanisms of DR pathogenesis and identify novel drug targets for this blinding disease.

Semaglutide-eye-catching results

Semaglutide is a glucagon-like peptide-1 receptor agonist used either orally every day or subcutaneously once a week for the treatment of type 2 diabetes mellitus and, more recently, at higher doses, for the treatment of obesity. Both diseases are reaching epidemic proportions and often coexist, posing patients with a high risk for cardiovascular disease and death. Therefore, an agent such as semaglutide, which offers clinically significant weight loss and cardiovascular benefits, is essential and will be increasingly used in high-risk patients. However, during the SUSTAIN clinical trial program (Semaglutide Unabated Sustainability in treat-ment of type 2 diabetes), a safety issue concerning the progression and worsening of diabetic retinopathy emerged. The existing explanation so far mainly supports the role of the magnitude and speed of HbA1c reduction, a phenomenon also associated with insulin treatment and bariatric surgery. Whether and to which extent the effect is direct is still a matter of debate and an intriguing topic to investigate for suitable preventative and rehabilitative purposes. In this minireview, we will summarize the available data and suggest guidelines for a comprehensive semaglutide clinical utilization until new evidence becomes available.

Retinal Microvasculature and Neural Changes and Dietary Patterns in an Older Population in Southern Italy

BACKGROUND

Like other parts of the body, the retina and its neurovascular system are also affected by age-related changes. The rising age of populations worldwide makes it important to study the pathologies related to age and their potential risk factors, such as diet and eating habits. The aim of this study was to investigate the predictive power of food groups versus retinal features among noninstitutionalized older adults from Southern Italy using a machine learning approach.

METHODS

We recruited 530 subjects, with a mean age of 74 years, who were drawn from the large population of the Salus in Apulia Study. In the present cross-sectional study, eating habits were assessed with a validated food frequency questionnaire. For the visual assessment, a complete ophthalmic examination and optical coherence tomography-angiography analyses were performed.

RESULTS

The analyses identified 13 out of the 28 food groups as predictors of all our retinal variables: grains, legumes, olives-vegetable oil, fruiting vegetables, other vegetables, fruits, sweets, fish, dairy, low-fat dairy, red meat, white meat, and processed meat.

CONCLUSIONS

Eating habits and food consumption may be important risk factors for age-related retinal changes. A diet that provides the optimal intake of specific nutrients with antioxidant and anti-inflammatory powers, including carotenoids and omega-3 fatty acids, could have beneficial effects.

The U-Shape Relationship between Triglyceride-Glucose Index and the Risk of Diabetic Retinopathy among the US Population

Objective: To explore the association of diabetic retinopathy (DR) with TyG index and TyG-related parameters among the United States population. Methods: This cross-sectional study is conducted in adults with diabetes mellitus based on the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. Multivariate logistic regression, restricted cubic spline, trend test, receiver operating characteristic curve and subgroup analysis are adopted to uncover the association of DR with TyG index and TyG-related parameter levels in diabetics. Results: An aggregate of 888 eligible participants with diabetes is included, involving 263 (29.6%) patients with DR. The participants are stratified according to the quartile of TyG index and TyG-related parameters (Q1–Q4). Following the adjustments of the confounding factors, a multivariate logistic regression analysis finds that TyG-BMI, TyG index and Q4-TyG index are significant risk factors for DR. The restricted cubic spline shows that TyG index and the DR risk of diabetes patients are proved to be U-shaped related (p for nonlinearity = 0.001). Conclusions: The triglyceride-glucose index has a U-shaped correlation with the risk of diabetic retinopathy, which has potential predictive value.

Diabetic retinopathy as the leading cause of blindness and early predictor of cascading complications-risks and mitigation

Proliferative diabetic retinopathy (PDR) the sequel of diabetic retinopathy (DR), a frequent complication of diabetes mellitus (DM), is the leading cause of blindness in the working-age population. The current screening process for the DR risk is not sufficiently effective such that often the disease is undetected until irreversible damage occurs. Diabetes-associated small vessel disease and neuroretinal changes create a vicious cycle resulting in the conversion of DR into PDR with characteristic ocular attributes including excessive mitochondrial and retinal cell damage, chronic inflammation, neovascularisation, and reduced visual field. PDR is considered an independent predictor of other severe diabetic complications such as ischemic stroke. A "domino effect" is highly characteristic for the cascading DM complications in which DR is an early indicator of impaired molecular and visual signaling. Mitochondrial health control is clinically relevant in DR management, and multi-omic tear fluid analysis can be instrumental for DR prognosis and PDR prediction. Altered metabolic pathways and bioenergetics, microvascular deficits and small vessel disease, chronic inflammation, and excessive tissue remodelling are in focus of this article as evidence-based targets for a predictive approach to develop diagnosis and treatment algorithms tailored to the individual for a cost-effective early prevention by implementing the paradigm shift from reactive medicine to predictive, preventive, and personalized medicine (PPPM) in primary and secondary DR care management.

Pro-Inflammatory diet accounts for higher prevalence of retinopathy in diabetes participants rather than normal glucose and prediabetes: Results from NHANES, 2005-2008

Retinopathy is a chronic inflammatory disease whose prognosis could be improved with dietary interventions. However, the association between a pro-inflammatory diet and the prevalence of retinopathy has not been fully elucidated. We assess the association between the dietary inflammatory index (DII), which is a comprehensive index determining inflammatory potential derived from food parameters according to literature, and the prevalence of retinopathy based on the data from the National Health and Nutritional Examination Survey (NHANES) 2005-2008 involving 2,403 participants. Energy-adjusted DII (E-DII) was not related to the occurrence of retinopathy in the general, non-diabetic, or middle-aged participants. In the diabetic and aged participants, one unit increment of E-DII accounted for 14 and 15% higher the prevalence of retinopathy respectively. The highest E-DII group had a 78 and 79% higher prevalence of retinopathy than the lowest group respectively. After adjusting for several covariables, the highest E-DII group was still associated with a 68% increase in retinopathy in diabetic patients. These results suggest that E-DII is positively associated with the prevalence of diabetic retinopathy among diabetic patients.

A risk prediction model for type 2 diabetes mellitus complicated with retinopathy based on machine learning and its application in health management

Objective

This study aimed to establish a risk prediction model for diabetic retinopathy (DR) in the Chinese type 2 diabetes mellitus (T2DM) population using few inspection indicators and to propose suggestions for chronic disease management.

Methods

This multi-centered retrospective cross-sectional study was conducted among 2,385 patients with T2DM. The predictors of the training set were, respectively, screened by extreme gradient boosting (XGBoost), a random forest recursive feature elimination (RF-RFE) algorithm, a backpropagation neural network (BPNN), and a least absolute shrinkage selection operator (LASSO) model. Model I, a prediction model, was established through multivariable logistic regression analysis based on the predictors repeated ≥3 times in the four screening methods. Logistic regression Model II built on the predictive factors in the previously released DR risk study was introduced into our current study to evaluate the model's effectiveness. Nine evaluation indicators were used to compare the performance of the two prediction models, including the area under the receiver operating characteristic curve (AUROC), accuracy, precision, recall, F1 score, balanced accuracy, calibration curve, Hosmer-Lemeshow test, and Net Reclassification Index (NRI).

Results

When including predictors, such as glycosylated hemoglobin A1c, disease course, postprandial blood glucose, age, systolic blood pressure, and albumin/urine creatinine ratio, multivariable logistic regression Model I demonstrated a better prediction ability than Model II. Model I revealed the highest AUROC (0.703), accuracy (0.796), precision (0.571), recall (0.035), F1 score (0.066), Hosmer-Lemeshow test (0.887), NRI (0.004), and balanced accuracy (0.514).

Conclusion

We have built an accurate DR risk prediction model with fewer indicators for patients with T2DM. It can be used to predict the individualized risk of DR in China effectively. In addition, the model can provide powerful auxiliary technical support for the clinical and health management of patients with diabetes comorbidities.

Dietary Intake and Diabetic Retinopathy: A Systematic Review of the Literature

Diabetic retinopathy (DR) is a common microvascular complication of diabetes mellitus. The evidence connecting dietary intake and DR is emerging, but uncertain. We conducted a systematic review to comprehensively summarize the current understanding of the associations between dietary consumption, DR and diabetic macular edema (DME). We systematically searched PubMed, Embase, Medline, and the Cochrane Central Register of Controlled Trials between January 1967 to May 2022 for all studies investigating the effect of diet on DR and DME. Of the 4962 articles initially identified, 54 relevant articles were retained. Our review found that higher intakes of fruits, vegetables, dietary fibers, fish, a Mediterranean diet, oleic acid, and tea were found to have a protective effect against DR. Conversely, high intakes of diet soda, caloric intake, rice, and choline were associated with a higher risk of DR. No association was seen between vitamin C, riboflavin, vitamin D, and milk and DR. Only one study in our review assessed dietary intake and DME and found a risk of high sodium intake for DME progression. Therefore, the general recommendation for nutritional counseling to manage diabetes may be beneficial to prevent DR risk, but prospective studies in diverse diabetic populations are needed to confirm our findings and expand clinical guidelines for DR management.

Physical Activity Status and Diabetic Retinopathy: A Review

Substantial evidence highlights the association between physical inactivity and diabetes onset and complications. Little is known regarding the link between physical inactivity and diabetic retinopathy in terms of onset, progression, and severity. This review aims to investigate these associations and understand the underlying mechanisms behind these associations. Decreased sedentary times and the inclusion of more physical activity have been linked to the delayed onset and progression of diabetic retinopathy and less severe forms of said condition. Physical activity provides both protective and anti-inflammatory effects on the retina. Further research is needed to understand and elucidate the exact mechanisms by which lack of physical activity affects retinal health and the onset, progression, and severity of diabetic retinopathy.