Physical activity and risk of diabetic retinopathy: a systematic review and meta-analysis

The Quantitative Impact of Visual Function on Accelerometer-measured Physical Activity in Older United States Adults: A Nationwide Cross-sectional Analysis

Purpose

To explore the impact of objective vision measures on novel metrics of objectively-measured physical activity (PA) in a nationally representative sample of United States (US) older adults.

Design

Cross-sectional analysis using data from the National Health and Aging Trends Study.

Participants

Adults had their distance and near visual acuity (VA) and contrast sensitivity (CS) tested. Any objective vision impairment (VI), defined as any VI in distance VA, near VA, or CS, was the primary exposure. Physical activity data were collected using the Actigraph CentrePoint Insight Watch worn for 7 days.

Methods

Multivariable regression models were used to investigate the association between vision and PA measures. All analyses accounted for the survey design and models were adjusted for age, sex, race, living arrangement, education, and comorbidities.

Main Outcome Measures

Physical activity metrics included (1) total daily activity (active minutes per day, number of active bouts, and mean length of active bouts), (2) activity fragmentation, and (3) time until 75% activity. An active bout was defined as ≥ 1 consecutive active minute. Activity fragmentation was defined as the probability of an active minute being followed by a sedentary minute, with higher values indicating more fragmented activity. Time until 75% activity was defined as the time taken to complete 75% of daily PA starting from their first active bout.

Results

Among 723 participants, sampled from 10 443 338 older adults in the US, 30% had any objective VI. Any objective VI was significantly associated with lower number of active minutes per day (7.8% fewer [95% confidence interval {CI}: -13.6% to -1.7%]), shorter active bouts (7.0% shorter [95% CI: -12.3% to -1.4%]), and greater activity fragmentation (2.5% [95% CI: 0.8% to 4.2%]), while no associations were found with number of active bouts. Time until 75% activity did not significantly differ between adults with any objective VI and those without (P = 0.34).

Conclusions

Older US adults with any objective VI displayed lower total daily activity, as well as more fragmented, shorter periods of PA, despite having a similar number of active bouts compared to their normally sighted counterparts. Implementing interventions that increase bout duration may help promote PA in adults with VI.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Assessing the importance of risk factors for diabetic retinopathy in patients with type 2 diabetes mellitus: Results from the classification and regression tree models

BACKGROUND

Diabetic retinopathy (DR) is one of the serious complications of diabetes mellitus (DM). Many studies have identified the risk factors associated with DR, but there is not much evidence on the importance of these factors for DR. This study aimed to investigate the associated factors for patients with type 2 DM (T2DM) and calculate the importance of the identified factors.

MATERIALS AND METHODS

Using probability proportionate to size sampling method in this community-based cross-sectional study, 22 community health service centers were selected from 10 administrative districts in Shenzhen, China. Approximately 60 T2DM patients were recruited from each center. The participants completed a structural questionnaire, had their venous blood collected, and underwent medical examinations and fundus photography. Logistic regression models were used to identify the risk factors of DR. The classification and regression tree (CART) model was used to calculate the importance of the identified risk factors.

RESULTS

This study recruited 1097 T2DM patients, 266 of whom were identified as having DR, yielding a prevalence rate of 24.3% (95% confidence interval [CI]: 21.7%-26.9%). Results showed that a longer duration of DM, indoor-type lifestyle, and higher levels of hemoglobin A1c (HbA1c) or urea increased the risk of DR. Patients with HbA1c values ≥7% were about 2.45 times (odds ratio: 2.45; 95% CI: 1.83-3.29) more likely to have DR than their counterparts. The CART model found that the values of variable importance for HbA1c, DM duration, lifestyle (i.e., indoor type), and urea were 48%, 37%, 10%, and 4%, respectively.

CONCLUSION

The prevalence of DR is high for T2DM patients who receive DM health management services from the primary healthcare system. HbA1c is the most important risk factor for DR. Integration of DR screening and HbA1c testing into the healthcare services for T2DM to reduce vision impairment and blindness is urgently warranted.

A tree-based corpus annotated with Cyber-Syndrome, symptoms, and acupoints

Prolonged and over-excessive interaction with cyberspace poses a threat to people's health and leads to the occurrence of Cyber-Syndrome, which covers not only physiological but also psychological disorders. This paper aims to create a tree-shaped gold-standard corpus that annotates the Cyber-Syndrome, clinical manifestations, and acupoints that can alleviate their symptoms or signs, designating this corpus as CS-A. In the CS-A corpus, this paper defines six entities and relations subject to annotation. There are 448 texts to annotate in total manually. After three rounds of updating the annotation guidelines, the inter-annotator agreement (IAA) improved significantly, resulting in a higher IAA score of 86.05%. The purpose of constructing CS-A corpus is to increase the popularity of Cyber-Syndrome and draw attention to its subtle impact on people's health. Meanwhile, annotated corpus promotes the development of natural language processing technology. Some model experiments can be implemented based on this corpus, such as optimizing and improving models for discontinuous entity recognition, nested entity recognition, etc. The CS-A corpus has been uploaded to figshare.

Effects and potential mechanisms of exercise and physical activity on eye health and ocular diseases

In the field of eye health, the profound impact of exercise and physical activity on various ocular diseases has become a focal point of attention. This review summarizes and elucidates the positive effects of exercise and physical activities on common ocular diseases, including dry eye disease (DED), cataracts, myopia, glaucoma, diabetic retinopathy (DR), and age-related macular degeneration (AMD). It also catalogues and offers exercise recommendations based on the varying impacts that different types and intensities of physical activities may have on specific eye conditions. Beyond correlations, this review also compiles potential mechanisms through which exercise and physical activity beneficially affect eye health. From mitigating ocular oxidative stress and inflammatory responses, reducing intraocular pressure, enhancing mitochondrial function, to promoting ocular blood circulation and the release of protective factors, the complex biological effects triggered by exercise and physical activities reveal their substantial potential in preventing and even assisting in the treatment of ocular diseases. This review aims not only to foster awareness and appreciation for how exercise and physical activity can improve eye health but also to serve as a catalyst for further exploration into the specific mechanisms and key targets through which exercise impacts ocular health. Such inquiries are crucial for advancing innovative strategies for the treatment of eye diseases, thereby holding significant implications for the development of new therapeutic approaches.

Sight-threatening diabetic retinopathy and its predictors among patients with diabetes visiting Adare General Hospital in Southern Ethiopia: a hospital-based cross-sectional study

OBJECTIVE

The study aimed to determine the prevalence of sight-threatening diabetic retinopathy and its predictors among patients with diabetes attending Adare General Hospital in Southern Ethiopia.

DESIGN

A hospital-based cross-sectional study was conducted using a systematic random sampling method.

SETTING

The study was conducted at the diabetic clinic of Adare General Hospital in Sidama region, Southern Ethiopia.

PARTICIPANTS

The study included 391 patients with diabetes aged ≥18 years who had attended the diabetic clinic of Adare General Hospital in Southern Ethiopia.

MAIN OUTCOME MEASURES

Data were collected using questionnaires completed by an interviewer, a review of medical records and eye examinations.

RESULT

The study included 391 patients with diabetes with a median age of 49 years. The prevalence of sight-threatening diabetic retinopathy was 10.7% (95% CI: 7.7% to 14%). Rural dwellers (adjusted OR (AOR)=2.17, 95% CI: 1.05 to 4.46), duration of diabetes ≥6 years (AOR=2.43, 95% CI: 1.06 to 5.57), poor glycaemic control (AOR=2.80, 95% CI: 1.03 to 7.64), low physical activity (AOR=2.85, 95% CI: 1.01 to 8.05), hypertension (AOR=3.25, 95% CI: 1.48 to 7.15) and diabetic peripheral neuropathy (AOR=3.32, 95% CI: 1.18 to 9.33) were significantly associated with sight-threatening diabetic retinopathy.

CONCLUSION

This study showed a high prevalence of sight-threatening diabetic retinopathy. Sight-threatening diabetic retinopathy was significantly associated with modified factors such as glycaemic control, hypertension, physical activity and diabetic peripheral neuropathy. Therefore, all patients with diabetes were recommended to maintain normal blood glucose, avoid hypertension, exercise regularly and have regular eye examinations.

Deep learning innovations in diagnosing diabetic retinopathy: The potential of transfer learning and the DiaCNN model

Diabetic retinopathy (DR) is a significant cause of vision impairment, emphasizing the critical need for early detection and timely intervention to avert visual deterioration. Diagnosing DR is inherently complex, as it necessitates the meticulous examination of intricate retinal images by experienced specialists. This makes the early diagnosis of DR essential for effective treatment and prevention of eventual blindness. Traditional diagnostic methods, relying on human interpretation of medical images, face challenges in terms of accuracy and efficiency. In the present research, we introduce a novel method that offers superior precision in DR diagnosis, compared to traditional methods, by employing advanced deep learning techniques. Central to this approach is the concept of transfer learning. This entails the utilization of pre-existing, well-established models, specifically InceptionResNetv2 and Inceptionv3, to extract features and fine-tune selected layers to cater to the unique requirements of this specific diagnostic task. Concurrently, we also present a newly devised model, DiaCNN, which is tailored for the classification of eye diseases. To prove the efficacy of the proposed methodology, we leveraged the Ocular Disease Intelligent Recognition (ODIR) dataset, which comprises eight different eye disease categories. The results are promising. The InceptionResNetv2 model, incorporating transfer learning, registered an impressive 97.5% accuracy in both the training and testing phases. Its counterpart, the Inceptionv3 model, achieved an even more commendable 99.7% accuracy during training, and 97.5% during testing. Remarkably, the DiaCNN model showcased unparalleled precision, achieving 100% accuracy in training and 98.3% in testing. These figures represent a significant leap in classification accuracy when juxtaposed with existing state-of-the-art diagnostic methods. Such advancements hold immense promise for the future, emphasizing the potential of our proposed technique to revolutionize the accuracy of DR and other eye disease diagnoses. By facilitating earlier detection and more timely interventions, this approach stands poised to significantly reduce the incidence of blindness associated with DR, thus heralding a new era of improved patient outcomes. Therefore, this work, through its novel approach and stellar results, not only pushes the boundaries of DR diagnostic accuracy but also promises a transformative impact in early detection and intervention, aiming to substantially diminish DR-induced blindness and champion enhanced patient care.

Leisure-Time Physical Activity and Risk of Microvascular Complications in Individuals With Type 2 Diabetes: A UK Biobank Study

OBJECTIVE

The aim of this study was to determine dose-response associations, including the minimal effective level, between leisure-time physical activity and risk of incident neuropathy, nephropathy, and retinopathy.

RESEARCH DESIGN AND METHODS

This cohort study included 18,092 individuals with type 2 diabetes from the UK Biobank. Self-reported leisure-time physical activity was converted into MET-hours per week. Participants were categorized into no physical activity (0 MET-h/week), below recommendations (0-7.49 MET-h/week), at recommendations (7.5-14.9 MET-h/week), and above recommendations (≥15 MET-h/week). Microvascular complications were identified from hospital inpatient records using diagnosis codes. We used Cox proportional hazards regression analysis to calculate adjusted hazard ratios (aHRs) and restricted cubic splines to identify the minimal effective level of physical activity.

RESULTS

During a median follow-up of 12.1 years, 672 individuals (3.7%) were diagnosed with neuropathy, 1,839 (10.2%) with nephropathy, and 2,099 (11.7%) with retinopathy. Any level of physical activity was associated with a lower risk of neuropathy and nephropathy but not retinopathy. Compared with those reporting no physical activity, the aHR of neuropathy was 0.71 (95% CI 0.53, 0.90) below recommendations, 0.73 (0.56, 0.96) at recommendations, and 0.67 (0.52, 0.87) above recommendations. Corresponding aHRs for nephropathy were 0.79 (0.68, 0.92), 0.80 (0.67, 0.95), and 0.80 (0.68, 0.95). The association with retinopathy was weaker, with aHRs of 0.91 (0.78, 1.06), 0.91 (0.77, 1.08), and 0.98 (0.84, 1.15), respectively.

CONCLUSIONS

Any level of leisure-time physical activity was associated with a lower risk of neuropathy and nephropathy but not retinopathy in individuals with type 2 diabetes. For both neuropathy and nephropathy, the minimal effective physical activity level may correspond to <1.5 h of walking per week.

The effect of moderate-intensity aerobic exercise on non-proliferative diabetic retinopathy in type II diabetes mellitus patients: A clinical trial

INTRODUCTION

Diabetic retinopathy (DR) is one of the most threatening complications of diabetes and a leading cause of visual loss in working-age population. Although exercise is beneficial in diabetes, previous studies have showed contradictory and inconclusive results on how it effects DR. In this study, we aimed to investigate the effect of moderate-intensity aerobic exercise on non-proliferative diabetic retinopathy.

MATERIALS & METHODS

In this before-after clinical trial, 40 patients with diabetic retinopathy were enrolled by convenient sampling method in Shahid Labbafinejad Hospital in Tehran during 2021-2022. Before the intervention, central macular thickness (CMT, microns) measured by optical coherence tomography (OCT) and fasting blood sugar (FBS, mg/dl) were obtained. Then, patients took part in a 12-week moderate-intensity aerobic exercise (3 sessions per week, each session 45 min). Data were analyzed using SPSS version 26.0.

RESULTS

Out of 40 examined patients, 21 (52.5 %) were male and 19 (47.5 %) were female. The mean age of the patients was 50.8 years. The mean rank of FBS (mg/dl) significantly decreased from 21.12 before the exercise to 8.75 after the exercise (p < 0.001). Also, the mean rank of CMT (microns) showed a significant decrease from 21.11 before the intervention to 16.20 after the exercise (p < 0.001). There was a significant positive correlation between patients' age and FBS (mg/dl) before (rho = 0.457, p = 0.003) and after (rho = 0.365, p = 0.021) the intervention. Also, a significant positive correlation was found between patients' age and CMT (microns) before (rho = 0.525, p = 0.001) and after (rho = 0.461, p = 0.003) moderate exercise.

CONCLUSION

Moderate-intensity aerobic exercise leads to lower FBS (mg/dl) and CMT (microns) in patients with diabetic retinopathy, so it may be beneficial for diabetic patients to avoid sedentary lifestyle.

Diet and ideal food pyramid to prevent or support the treatment of diabetic retinopathy, age-related macular degeneration, and cataracts

Many eye diseases, such as diabetic retinopathy (DR), age-related macular degeneration (AMD), and cataracts are preventable and treatable with lifestyle. The objective of this review is to assess the most recent research on the ideal dietary approach to prevent or support the treatment of DR, AMD, and cataracts, as well as to construct a food pyramid that makes it simple for people who are at risk of developing these pathologies to decide what to eat. The food pyramid presented here proposes what should be consumed every day: 3 portions of low glycemic index (GI) grains (for fiber and zinc content), 5 portions (each portion: ≥200 g/day) of fruits and vegetables (spinach, broccoli, zucchini cooked, green leafy vegetables, orange, kiwi, grapefruit for folic acid, vitamin C, and lutein/zeaxanthin content, at least ≥42 μg/day, are to be preferred), extra virgin olive (EVO) oil (almost 20 mg/day for vitamin E and polyphenols content), nuts or oil seeds (20-30 g/day, for zinc content, at least ≥15.8 mg/day); weekly: fish (4 portions, for omega-3 content and eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) 0.35-1.4 g/day), white meat (3 portions for vitamin B12 content), legumes (2 portions for vegetal proteins), eggs (2 portions for lutein/zeaxanthin content), light cheeses (2 portions for vitamin B6 content), and almost 3-4 times/week microgreen and spices (saffron and curcumin). At the top of the pyramid, there are two pennants: one green, which indicates the need for personalized supplementation (if daily requirements cannot be met through diet, omega-3, and L-methylfolate supplementation), and one red, which indicates that certain foods are prohibited (salt and sugar). Finally, 3-4 times per week, 30-40 min of aerobic and resistance exercises are required.

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.

The Correlation between Waist Circumference and the Pro-Inflammatory Adipokines in Diabetic Retinopathy of Type 2 Diabetes Patients

Central obesity is one of the major risk factors for type 2 diabetes mellitus (DM), and the most common complication of DM is diabetic retinopathy. However, the exact relationship between obesity and DR remains unknown. In this study, we evaluate the effect of obesity on DR by comparing the aqueous humor-derived adipokines. For the analysis, 37 DR patients and 29 non-DR-patients participated. To evaluate the obesity of the patients, body mass index (BMI) and waist circumference (WC) were used. By comparing the concentrations of adipokines obtained from the aqueous humor of the two groups, the relationship between DR and adipokines was analyzed. In addition, by analyzing the correlation between obesity and adipokines in patients, the relationship between central obesity and DR was finally confirmed. The WC was significantly higher in patients than in the non-patient group. The concentrations of all adipokines compared in this study were significantly higher in the DR group than in the non-DM group (p < 0.05). Among them, adiponectin, leptin, TNF-α, Factor D (adipsin), lipocalin-2 (NGAL), Serpin E1 (PAI-1), and CXCL8 (IL-8) were confirmed to have a positive correlation with central obesity (defined as WC). These findings suggest that central obesity is strongly associated with the risk of DR.

Physical Activity and Risk of Major Diabetes-Related Complications in Individuals With Diabetes: A Systematic Review and Meta-Analysis of Observational Studies

BACKGROUND

Physical activity is a cornerstone in diabetes management; however, evidence synthesis on the association between physical activity and long-term diabetes-related complications is scarce.

PURPOSE

To summarize and evaluate findings on physical activity and diabetes-related complications, we conducted a systematic review and meta-analysis.

DATA SOURCES

We searched PubMed, Web of Science, and the Cochrane Library for articles published up to 6 July 2021.

STUDY SELECTION

We included prospective studies investigating the association between physical activity and incidence of and mortality from diabetes-related complications, i.e., cardiovascular disease (CVD), coronary heart disease, cerebrovascular events, heart failure, major adverse cardiovascular events, and microvascular complications such as retinopathy and nephropathy, in individuals with diabetes.

DATA EXTRACTION

Study characteristics and risk ratios with 95% CIs were extracted. Random-effects meta-analyses were performed, and the certainty of evidence and risk of bias were evaluated with use of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) and Risk Of Bias In Non-randomised Studies - of Interventions (ROBINS-I) tools.

DATA SYNTHESIS

Overall, 31 studies were included. There was moderate certainty of evidence that high versus low levels of physical activity were inversely associated with CVD incidence, CVD mortality (summary risk ratio 0.84 [95% CI 0.77, 0.92], n = 7, and 0.62 [0.55, 0.69], n = 11), and microvascular complications (0.76 [0.67, 0.86], n = 8). Dose-response meta-analyses showed that physical activity was associated with lower risk of diabetes-related complications even at lower levels. For other outcomes, similar associations were observed but certainty of evidence was low or very low.

LIMITATIONS

Limitations include residual confounding and misclassification of exposure.

CONCLUSIONS

Physical activity, even below recommended amounts, was associated with reduced incidence of diabetes-related complications.

Proportion and risk factors of diabetic retinopathy by stage in less-developed rural areas of Hunan province of China: A multi-site cross-sectional study

Aims

To investigate the proportion and risk factors of diabetic retinopathy (DR) by stages in less-developed rural areas in Hunan Province of China.

Background

DR is common among people with diabetes but not well recognized in less-developed rural areas. There is insufficient evidence on the risk factors of DR by stages, making it challenging to develop targeted prevention and intervention programs for DR in primary care settings.

Methods

A multi-site cross-sectional survey was conducted among people with type 2 diabetes mellitus (T2DM) from four less-developed counties in Hunan Province of China. All participants underwent the screening of DR via digital fundus photography and completed self-reported questionnaires on their socio-demographic and clinical characteristics, diabetes self-efficacy, diabetes self-care behaviors, social support, family function, and health service accessibility. The multinomial logistic regression models were employed to explore the risk factors of DR by stage, which were selected based on the socio-ecological model, literature, and clinical experience.

Results

A total of 196 participants were included in this study with an average age of 57.43 ± 10.26. 59.6% (117/196) of the participants were identified as DR, including 37.2% (73/196) non-proliferative DR and 22.4% (44/196) proliferative DR. Compared to the non-DR group, the risk factors of non-proliferative DR and proliferative DR were diabetes duration (OR: 1.10, 95 CI%: 1.04–1.17; OR: 1.14, 95 CI% 1.06–1.22) and self-monitoring of blood glucose (OR: 1.09, 95 CI% 1.01–1.17; OR: 1.11, 95 CI%: 1.02–1.20); the protective factors of non-proliferative DR was accessible complication prevention and management education (OR: 0.37, 95 CI% 0.14–0.94) while the protective factors of proliferative DR were physical activities (OR: 0.89, 95 CI%: 0.80–0.98). Compared to the non-proliferative DR group, the protective factors of proliferative DR were physical activities (OR: 0.89, 95 CI% 0.02–0.89) and family function (OR: 0.84, 95 CI%: 0.04–0.84).

Conclusion

DR was prevalent among people with T2DM in less-developed rural areas, indicating the need of strengthening DR screening. Risk factors of DR varied by stage while sharing some common factors. Future DR prevention and intervention programs may benefit from improving these factors to reduce the risk of DR by stage.

Associations between psycho-behavioral risk factors and diabetic retinopathy: NHANES (2005-2018)

Introduction

Diabetes mellitus (DM) and diabetic retinopathy (DR) increase the global burden. Since their pathogenesis is complex, it is necessary to use the biopsychosocial model to discover the most effective strategies. The study is aimed to investigate the psycho-behavioral factors of DR and confirm the discrepancies from previous studies.

Research design and methods

The study comprised seven cycles of cross-sectional data of the National Health and Nutrition Examination Survey (NHANES) from 2005-2006 to 2017-2018. Samples of DM were selected from this complex multi-stage probability sample and divided into the non-DR and DR groups, where 4,426 samples represented 18,990,825 individuals after weighting. This study comprehensively explored the biological, social, and psychological risk factors of DR, among which the biological factors included blood pressure, blood routine, HbA1c%, blood glucose, the duration of DM, family history, comorbidities, and treatment methods. Social aspects include gender, education, income, insurance, smoking, drinking, sleep habits, and recreational activities. The Patient Health Questionnaire-9 (PHQ-9) was used to assess the psychological state. Taylor series regression was used to examine the connection between factors and DR.

Results

Men accounted for 55.5% of the DR group (P = 0.0174). Lymphocyte count, insulin treatment, heart failure, stroke, liver condition, and renal failure showed significant differences in DR (P < 0.05). The incidence of depression in DR was 40.5%. Mild to moderate depression [odds ratio was associated with DR [(OR) = 1.37, 95% confidence interval (CI): 1.06-1.79], but there was no statistical difference in severe depression (OR = 1.34, 95% CI: 0.83-2.17). Although ≤ 6 h of sleep was associated with DR (OR = 1.38, 95% CI: 1.01-1.88), we found no statistical differences in alcohol consumption, recreational activities, or sedentary time between the two groups in our current study (P > 0.05).

Conclusions

The biological risk factors of DR are significant. It showed that stroke is associated with DR, and retinal exams have the potential value as a screening tool for the brain. Besides, psycho-behavioral risk factors of DR should also be paid attention. Our study highlights that mild and moderate depression and ≤6 h of sleep are distinguishably associated with DM complicated with DR. It indicates that psycho-behavioral risk factors confer a vital influence on diabetic health care and DR.

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.

Association of objective and subjective far vision impairment with perceived stress among older adults in six low- and middle-income countries

OBJECTIVES

To assess the association between far vision impairment (objective and subjective) and perceived stress among older adults from six low- and middle-income countries (LMICs, i.e., China, Ghana, India, Mexico, Russia, and South Africa).

METHODS

Data from the WHO Study on global AGEing and adult health were analyzed. Objective visual acuity was measured using the tumbling E LogMAR chart and was used as a four-category variable (no, mild, moderate, and severe visual impairment). Subjective visual impairment referred to difficulty in seeing and recognizing an object or a person across the road. Using two questions from the Perceived Stress Scale, a perceived stress variable was computed, and ranged from 0 (lowest stress) to 100 (highest stress). Multivariable linear regression with perceived stress as the outcome was conducted.

RESULTS

Data on 14,585 adults aged ≥65 years [mean (SD) age 72.6 (11.5) years; 55.0% females] were analyzed. Only severe objective visual impairment (versus no visual impairment) was significantly associated with higher levels of stress (b = 6.91; 95% CI = 0.94-12.89). In terms of subjective visual impairment, compared with no visual impairment, mild (b = 2.67; 95% CI = 0.56-4.78), moderate (b = 8.18; 95% CI = 5.84-10.52), and severe (b = 11.86; 95% CI = 9.11-14.61) visual impairment were associated with significantly higher levels of perceived stress.

CONCLUSIONS

This large study showed that far vision impairment was associated with increased perceived stress levels among older adults in LMICs. Increased availability of eye care services may reduce stress among those with visual impairment in LMICs, while more research is needed to better characterize the directionality of the far vision impairment-perceived stress relationship.

Pathological eating behaviours and risk of retinopathy in diabetes: a systematic review and meta-analysis

Background

Diabetes mellitus can cause several long-term macrovascular and microvascular complications including nephropathy, neuropathy, and retinopathy (DR). Several studies have reported positive associations between eating pathologies and DR; however, these studies have not been aggregated and sub-grouped into type of pathological eating behaviour, and the differences in risk according to type of eating behaviour is unknown. The aim of this review, therefore, was to aggregate risks of DR in populations with and without pathological eating behaviours, stratified according to eating behaviour.

Methods

A systematic review and meta-analysis was conducted. Major databases and grey literature were search from inception until 1/6/2021. Studies reporting the prevalence of pathological eating behaviours (against a control group with no pathological eating behaviours) in diabetic people with and without DR were included. Odds ratios were calculated from primary data.

Results

Seven studies with eight independent outcomes with a total of 1162 participants were included. The odds ratio of DR in the total pooled analysis was 2.94 (95%CI 1.86-4.64; p = <0.001; I2 = 29.59). Two types of eating behaviour yielded enough data for sub-group analysis. Eating disorder not otherwise specified yielded an odds ratio of 2.73 (95%CI 1.81-4.10; p = <0.001; I2 = 0.00), and binge eating disorder yielded an non-significant odds ratio of 0.92 (95%CI 0.31-2.77; p = 0.887;I2 = 0.00).

Discussion

The likelihood of DR increases almost three times in the presence of pathological eating behaviours. More studies are required to confirm this in clinical populations stratified by eating disorder. Practitioners working with people with diabetes should closely monitor eating behaviours to preclude this risk.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-022-00980-x.

Associations between diabetic retinopathy and modifiable risk factors: An umbrella review of meta-analyses

AIMS

Several modifiable risk factors have been meta-analysed for diabetic retinopathy (DR), such as physical activity and vitamin D status. To date, these factors have not been systematically aggregated and the credibility of evidence assessed. Therefore, the aim of this umbrella review was to aggregate all modifiable risks of DR and assess the credibility of the evidence.

METHODS

An umbrella review of meta-analyses was undertaken. For each meta-analytic association, random-effects effect size, 95% confidence intervals (CIs), heterogeneity, small-study effects, excess significance bias and 95% prediction intervals were calculated. The credibility of significant evidence (p < 0.05) was graded from I to IV, using pre-defined criteria.

RESULTS

After initial searches, 13 studies were included covering 34 independent outcomes (total participants = 824,372). Positive associations were found between insulin usage and diabetic macular oedema (RR = 4.5; 95% CI 3.1-6.6), and DR risk (RR = 2.3; 95% CI 1.4-3.9) in people with type 2 diabetes. Vitamin D deficiency was associated with DR risk (OR = 2.8; 95% CI 1.1-7.1), as was obesity (RR = 1.34; 95% CI 1.06-1.68) and sedentary behaviour (RR = 1.22; 95%CI 1.03-1.44). Intensive blood pressure targets (RR = 0.8 95%CI 0.8-1.0), and moderate physical activity (RR = 0.69; 95%CI 0.53-0.91) yielded significant protective associations with DR.

CONCLUSIONS

People with type 2 diabetes on insulin have a high risk of macular oedema and DR. Vitamin D deficiency yielded almost three times greater odds of DR, while intensive blood pressure control reduces DR risk by 20% and moderate physical activity by 31%. Healthcare professionals should use this evidence to identify those people most at risk to ensure that proper treatment and healthy lifestyles are recommended.

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

Diabetes is a major social problem. As shown by epidemiological studies, the world incidence of diabetes is increasing and so is the number of people suffering from its complications. Therefore, it is important to determine possible preventive tools. In the prevention of diabetic retinopathy, it is essential to control glycemia, lipid profile and blood pressure. This can be done not only by pharmacological treatment, but first of all by promoting a healthy lifestyle, changing dietary habits and increasing physical activity. In our work, we present a review of the literature to show that physical exercise and an adequate diet can significantly reduce the risk of diabetes and diabetic retinopathy.

Factors protecting against diabetic retinopathy in a geriatric Indian cohort

Purpose:

Diabetic retinopathy (DR) is a potentially sight-threatening complication of diabetes mellitus. The majority of cases are in older adults. This study aims to evaluate modifiable and nonmodifiable protective factors against DR in a geriatric Indian population.

Methods:

This retrospective observational study uses data from a multitiered ophthalmology network to evaluate several demographic and clinical variables against diabetic retinopathy and visual acuity.

Results:

Our data show that high myopia, the female sex, and no cataract surgery are associated with lower prevalence of DR (OR = 0.21, 0.65, and 0.76, respectively; P < 0.001). We also found that among those with DR, people categorized as payers, retirees, and those living in urban or metropolitan areas have better visual acuity (OR = 0.65, 0.65, 0.83, and 0.73, respectively; P < 0.001). Among those with DR, females, presence of cataracts, and no cataract surgery had lower associations with sight-threatening DR (STDR) (OR = 0.68, 0.37, and 0.76, respectively; P < 0.001). Prevalence of DR decreased in older age groups while controlling for DM duration.

Conclusion:

It is probable that high myopia, the female sex, and better glycemic control are protective against DR and STDR in our study cohort of adults over 60 years of age. It is possible that occupations involving manual labor, delayed cataract surgery, and living past the age of 70 are also protective against DR.

Obesity and risk of age-related eye diseases: a systematic review of prospective population-based studies

BACKGROUND

Obesity is a public health challenge worldwide. The relationship between obesity and age-related eye diseases including cataract, glaucoma, age-related macular degeneration (AMD) and diabetic retinopathy (DR) have remained elusive.

DESIGN AND METHODS

We conducted a systematic review of three electronic databases for longitudinal population-based studies that described associations between measures of obesity including body mass index (BMI), waist-circumference (WC), and waist-to-hip ratio (WHR), and age-related eye diseases.

RESULTS

Our search yielded 1731 articles, of which 14, 10, 16 and 8 articles met our eligibility criteria for cataract, glaucoma, AMD and DR, respectively. BMI-defined obesity was positively associated with incident cataract, incident AMD and incident DR in Western populations, but in Asian populations associations for incident AMD were not significant and associations for incident DR were inverse. WC-defined obesity was associated with incident glaucoma in non-Western populations. WHR-defined obesity but not BMI-defined obesity was associated with the incidence or progression of AMD in two Western studies.

CONCLUSIONS

Overall, we found strong evidence supporting associations between obesity and age-related eye diseases. Further research on the association of abdominal obesity and effect of weight loss and physical activity on age-related eye diseases is warranted to support clinical and public health recommendations.

Iranian National Clinical Practice Guideline for Exercise in Patients with Diabetes

CONTEXT

Growing evidence highlights the importance of physical activity as a critical element for the prevention and control of diabetes. However, there is no clinical practice guideline focusing on the different aspects of exercise in patients with diabetes, especially for the Iranian population.

OBJECTIVE

We aimed to prepare and adopt a clinical practice guideline to provide well-defined, simple, and concise responses to certain questions related to physical activity and exercise in all patients with diabetes, including type 1, 2, and gestational diabetes mellitus (GDM).

EVIDENCE ACQUISITION

A multidisciplinary team of experts in various fields (sports medicine specialists, endocrinologists, and cardiologists) developed the guideline. This group did the task in four stages: (1) identifying and refining the subject area using 17 clinical questions; (2) appraising evidence through a systematic review of the literature; (3) extracting recommendations from evidence and grading them as A, B, C, or D based on the quality, quantity, and consistency of existing evidence; and (4) subjecting the guideline to external review and finally selecting the recommendations with high scores of appropriateness and agreement. The final version was evaluated and approved by the National Deputy for Curative Affairs - Ministry of Health and Medical Education and has also been endorsed by the Iran Endocrine Society (IES) and Iranian Association of Sports and Exercise Medicine (IASEM).

RESULTS

The guideline consists of 52 recommendations addressing 17 important questions concerning different aspects of exercise prescription in Iranian patients with diabetes.

CONCLUSIONS

The guideline provides evidence-based information that may help physicians to prescribe exercise for Iranian patients with diabetes safely and effectively.

Evidence Gap and Knowledge Map of Physical Activity Research in Diabetes in Iran: A Scoping Review

CONTEXT

The important role of physical activity in the prevention and management of diabetes necessitates a review of current research to shed light on gaps in national diabetes guidelines.

EVIDENCE ACQUISITION

This scoping review was part of the Iran Diabetes Research Roadmap (IDRR) study. A systematic search was used based on the Arksey and O'Malley method consisting of six steps. The descriptive analysis was done with SPSS software. Additionally, VOS veiwer software was used to draw the knowledge map of the included studies.

RESULTS

There were 169 articles included from the beginning of 2015 to the end of 2019 in Iran. Aerobic and resistance exercises were types of physical activity with more number of articles. Most of the included clinical studies were randomized clinical trials and had a level of evidence two. Also, there was more interest in outcomes such as glycemic control and insulin sensitivity, metabolic syndrome, metabolism, and cardiovascular health. The network of co-authorship was drawn, and "controlled study", "male", and "rat" were the most frequent keywords.

CONCLUSIONS

The number of Iranian diabetes researchers on physical activity is increasing, and the majority of clinical studies had a high level of evidence. With maintaining previous interests and investigations, there should be more emphasis on research in elderly and children age groups as evidence gap in Iran. Also, longitudinal cohort studies should be highlighted and Iranian researchers should be encouraged to participate in new topics of research worldwide.

The Safety of Pharmacological and Surgical Treatment of Diabetes in Patients with Diabetic Retinopathy-A Review

BACKGROUND

Diabetes mellitus (DM) is a non-infectious pandemic of the modern world; it is estimated that in 2045 it will affect 10% of the world's population. As the prevalence of diabetes increases, the problem of its complications, including diabetic retinopathy (DR), grows. DR is a highly specific neurovascular complication of diabetes that occurs in more than one third of DM patients and accounts for 80% of complete vision loss cases in the diabetic population. We are currently witnessing many groundbreaking studies on new pharmacological and surgical methods of treating diabetes.

AIM

The aim of the study is to assess the safety of pharmacological and surgical treatment of DM in patients with DR.

MATERIAL AND METHODS

An analysis of the data on diabetes treatment methods currently available in the world literature and their impact on the occurrence and progression of DR.

RESULTS

A rapid decrease in glycaemia leads to an increased occurrence and progression of DR. Its greatest risk accompanies insulin therapy and sulfonylurea therapy. The lowest risk of DR occurs with the use of SGLT2 inhibitors; the use of DPP-4 inhibitors and GLP-1 analogues is also safe. Patients undergoing pancreatic islet transplants or bariatric surgeries require intensive monitoring of the state of the eye, both in the perioperative and postoperative period.

CONCLUSIONS

It is of utmost importance to individualize therapy in diabetic patients, in order to gradually achieve treatment goals with the use of safe methods and minimize the risk of development and progression of DR.

Differential effects of high-intensity interval training (HIIT) on choriocapillaris perfusion in healthy adults and patients with type 1 diabetes mellitus (T1DM)

PURPOSE

To investigate the effects of a four-week high-intensity interval training (HIIT) on choriocapillaris (CC) perfusion in young healthy adults and type 1 diabetes mellitus (T1DM) patients.

METHODS

Data of two HIIT studies with baseline to follow-up comparison were retrospectively analysed. Twenty healthy participants and twenty T1DM patients without clinical signs of diabetic retinopathy were included. All participants had performed a four-week all-out HIIT protocol with a total of 8 training sessions. Changes in physical fitness were assessed using power output at the individual aerobic lactate threshold (IANT). Optical coherence tomography angiography (OCTA) imaging was performed at baseline and follow-up. CC images were analysed for number, size and total area of flow deficits (FD), mean signal intensity, signal intensity standard deviation and kurtosis of signal intensity distribution.

RESULTS

At baseline, CC OCTA revealed a lower and more heterogeneous intensity signal in T1DM eyes (mean intensity signal and standard deviation of signal intensity, p < 0.001). Percent of CC FD area was greater in T1DM eyes (p < 0.001). While T1DM patients showed greater improvement of exercise capacity at IANT than healthy controls (group×time p = 0.0403), CC FD area and standard deviation of intensity increased in healthy controls but not in T1DM patients (group×time p ≤ 0.029). Moreover, linear regression slopes of FD region distribution differed significantly at baseline and follow-up (p = 0.0002) in healthy individuals but not in T1DM patients.

CONCLUSIONS

Effects of regular physical exercise performed as HIIT on CC perfusion were only seen in healthy participants, not in T1DM patients suggesting impaired CC adaptation in T1DM.

Exercise and Type 1 Diabetes

Diabetes mellitus (DM) is the most common endocrine and metabolic disease caused by absolute or insufficient insulin secretion. Under the context of an aging population worldwide, the number of diabetic patients is increasing year by year. Most patients with diabetes have multiple complications that severely threaten their survival and living quality. DM is mainly divided into type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). T1DM is caused by absolute lack of insulin secretion, so the current treatment for T1DM patients is exogenous insulin replacement therapy. At present, exercise therapy has been widely recognized in the prevention and treatment of diabetes, and regular aerobic exercise has become an important part of T1DM treatment. At the same time, exercise therapy is also used in conjunction with other treatments in the prevention and treatment of diabetic complications. However, for patients with T1DM, exercise still has the risk of hypoglycemia or hyperglycemia. T1DM Patients and specialist physician need to fully understand the effects of exercise on metabolism and implement individualized exercise programs. This chapter reviews the related content of exercise and T1DM.

Spermine oxidase: A promising therapeutic target for neurodegeneration in diabetic retinopathy

Diabetic Retinopathy (DR), is a significant public health issue and the leading cause of blindness in working-aged adults worldwide. The vision loss associated with DR affects patients' quality of life and has negative social and psychological effects. In the past, diabetic retinopathy was considered as a vascular disease; however, it is now recognized to be a neuro-vascular disease of the retina. Current therapies for DR, such as laser photocoagulation and anti-VEGF therapy, treat advanced stages of the disease, particularly the vasculopathy and have adverse side effects. Unavailability of effective treatments to prevent the incidence or progression of DR is a major clinical problem. There is a great need for therapeutic interventions capable of preventing retinal damage in DR patients. A growing body of evidence shows that neurodegeneration is an early event in DR pathogenesis. Therefore, studies of the underlying mechanisms that lead to neurodegeneration are essential for identifying new therapeutic targets in the early stages of DR. Deregulation of the polyamine metabolism is implicated in various neurodegenerative diseases, cancer, renal failure, and diabetes. Spermine Oxidase (SMOX) is a highly inducible enzyme, and its dysregulation can alter polyamine homeostasis. The oxidative products of polyamine metabolism are capable of inducing cell damage and death. The current review provides insight into the SMOX-regulated molecular mechanisms of cellular damage and dysfunction, and its potential as a therapeutic target for diabetic retinopathy. Structural and functional changes in the diabetic retina and the mechanisms leading to neuronal damage (excitotoxicity, loss of neurotrophic factors, oxidative stress, mitochondrial dysfunction etc.) are also summarized in this review. Furthermore, existing therapies and new approaches to neuroprotection are discussed.

The role of inflammation in diabetic eye disease

Mounting evidence suggests that immunological mechanisms play a fundamental role in the pathogenesis of diabetic retinopathy (DR) and diabetic macular edema (DME). Upregulation of cytokines and other proinflammatory mediators leading to persistent low-grade inflammation is believed to actively contribute to the DR-associated damage to the retinal vasculature, inducing breakdown of the blood-retinal barrier, subsequent macular edema formation, and promotion of retinal neovascularization. This review summarizes the current knowledge of the biological processes providing an inflammatory basis for DR and DME. In addition, emerging therapeutic approaches targeting inflammation are discussed, including blockade of angiopoietin 2 and other molecular targets such as interleukin (IL)-6, IL-1β, plasma kallikrein, and integrins.