Prevalence of Diabetic Retinopathy and Vision Loss in the Beijing Eye Study: the Potential Role of the Cerebrospinal Fluid Pressure

Global and Regional Prevalence of Diabetic Retinopathy; A Comprehensive Systematic Review and Meta-analysis

PURPOSE

We conducted a systematic search to estimate DR prevalence in different age and gender groups, and to evaluate the determinants of heterogeneity in its prevalence.

METHODS

A systematic and comprehensive search from inception to August 10, 2020, was done in international databases, including Scopus, PubMed, Web of Science, Embase, and other data sources without any restriction to find cross-sectional studies related to the prevalence of DR.

RESULTS

Of 6399 studies, 90 articles with a sample size of 563460 individuals and 204189 diabetic patients were analyzed. The estimated pooled prevalence of DR in the diabetic population in general; in female and in male was 28.41% (95% CI: 25.98 to 30.84); 25.93% (95% CI: 23.54 to 28.31) and 28.95% (95% CI: 26.57 to 31.32); respectively and the prevalence of DR showed no inter-gender difference. The heterogeneity of the pooled prevalence according to I² was 99% (p < .001). According to the meta-regression results, the variables of WHO region (Coefficient of AMRO vs SEARO: 15.56; p: 0.002), age (Coefficient of above 60 years vs below 40 year: 18.67; p: 0.001), type of DR (Coefficient: 19.01; p < .001), and publication year (Coefficient: -0.60; p: 0.001) had a significant correlation with heterogeneity.

CONCLUSION

One third of diabetic patients suffered from DR, mostly NPDR. DR increased markedly after the age of 60 years, which could be due to the longer duration of diabetes. Age, WHO region, type of DR, and publication year affected the heterogeneity in the prevalence of DR.

Fufang Xueshuantong protects retinal vascular endothelial cells from high glucose by targeting YAP

Fufang Xueshuantong (FXST), a Chinese patent medicine, is composed of Panax notoginseng, Salviae miltiorrhizae, Astragali Radix and Radix Scrophulariae and has been found to prevent diabetic retinopathy. Yes-associated protein (YAP) participates in the pathophysiology of retinal disease and promotes endothelial cell proliferation and angiogenesis. Although it is known that YAP activity is altered by FXST, the role of YAP in mediating the effect of FXST remains unclear. In high glucose-treated retinal vascular endothelial cells (RVECs), FXST significantly reduced cell viability, the number of migrating cells and tube length in the present study. Moreover, FXST decreased the levels of YAP mRNA and protein and inhibited the expression of vascular endothelial growth factor (VEGF). Transfection of sh-YAP into the cells decreased the ability of FXST to modulate cell migration and tube formation. The effect of FXST on VEGF expression was also decreased. Similar results were obtained when the cells were stimulated with a YAP inhibitor in combination with FXST. Thus, FXST is shown to protect high glucose-injured RVECs via YAP-mediated effects.

The influence of ageing and diabetic peripheral neuropathy on posture sway, tremor, and the time to achieve balance equilibrium

BACKGROUND

It is well recognized that ageing and diabetes are associated with reduced balance and impaired gait. However, one important factor may be not just balance, but how long it takes to achieve balance equilibrium after a balance challenge. This study examined the relationship between balance, tremor, and time to achieve balance after a challenge to stability in young and old individuals without and without diabetes.

METHODS

Twenty-four of the subjects were young controls, 22 were older controls, 23 were individuals with diabetes, and 21 were young people with diabetes. Posture sway, tremor, and time to achieve stability were assessed on a force plate during 8 progressively challenging balance tasks.

RESULTS

For postural sway, tremor and time to reach postural stability, there was a significant difference in all groups with the increased balance challenge of the 8 tests (P<0.01). However, ageing and diabetes made balance, tremor and time to reach stability worse. In general, the young group with diabetes, for example, had similar responses to the old group without diabetes.

CONCLUSIONS

In the subjects with diabetes, balance was poorer than the non-diabetes groups. The young subjects with diabetes showed similar results to the older subjects without diabetes. Diabetes subjects had more muscle tremor and a slower response time of the body to a balance challenge. This may account for increased falls in individuals with diabetes.

Long noncoding RNA MALAT1 acts as a competing endogenous RNA to regulate Amadori-glycated albumin-induced MCP-1 expression in retinal microglia by a microRNA-124-dependent mechanism

OBJECTIVE

To determine whether the long noncoding RNA MALAT1 may be involved in the inflammatory effect of Amadori-glycated albumin (AGA) in retinal microglia via a microRNA-124 (miR-124)-dependent mechanism.

METHODS

Diabetes mellitus was induced by streptozotocin (STZ) injection. The expression of monocyte chemotactic protein-1 (MCP-1) in the retinas of rats was determined using quantitative reverse transcription-PCR (qRT-PCR) analyses and enzyme-linked immunosorbent assay (ELISA). Both qRT-PCR and ELISA were used to detect the levels of MCP-1 mRNA and soluble MCP-1 protein in the primary rat retinal microglia treated with AGA. The regulation of a putative target of miR-124 was validated by luciferase reporter assays.

RESULTS

MALAT1 knockdown ameliorated diabetic retinopathy (DR) and inhibited MCP-1 release in the retinas of STZ-induced diabetic rats. The cultured retinal microglial cells treated with AGA-released MCP-1 in a dose- and time-dependent manner. In addition, AGA consistently induced MALAT1 expression in the retinal microglial cells. Next, we demonstrated that the expression of MCP-1 is controlled by miR-124, which binds to the 3'-UTR of MCP-1 in microglial cells. Luciferase reporter assays and RNA-binding protein immunoprecipitation assays showed that MALAT1 targets miR-124. Finally, we demonstrated that MALAT1 acts as a competing endogenous RNA by directly binding to miR-124 to regulate AGA-induced MCP-1 expression in microglial cells.

CONCLUSIONS

MALAT1-miR-124-MCP-1 signaling pathway may be involved in AGA-induced MCP-1 expression in microglial cells, which may provide a new approach for the treatment of DR.

Association of intraocular pressure-related factors and retinal vessel diameter with optic disc rim area in subjects with and without primary open angle glaucoma

IMPORTANCE

The data may support the notion that the intra-ocular pressure (IOP)-related factors and vascular factors were implicated concurrently in glaucomatous optic nerve damage.

BACKGROUND

To study the association of intraocular pressure (IOP)-related factors, IOP, trans-lamina cribrosa pressure difference (TLCPD), cerebrospinal fluid pressure (CSFP) and retinal vessel diameters (RVD), central retinal arteriolar equivalent (CRAE), central retinal venular equivalent (CRVE) with neuro-retinal rim area (RA).

DESIGN

A population-based, cross-sectional study.

PARTICIPANTS

A total of 6830 people aged 30 years and over.

METHODS

All participants underwent a comprehensive eye examination, fundus photograph-based measurements of RVD and Heidelberg retinal tomogram (HRT) measurement of optic disc.

MAIN OUTCOME MEASURES

RA, CRAE, CRVE, IOP, body mass index (BMI), CSFP and TLCPD.

RESULTS

Primary open-angle glaucoma (POAG) was diagnosed using two separate methods: 67 from expert consensus, and 125 from the International Society of Geographical and Epidemiologic Ophthalmology (ISGEO) classification. After excluding of those with high myopia or without gradable HRT images, 4194 non-glaucoma and 40 POAG were analysed for determinants of RA. On multivariable analysis determinants of reduced RA were POAG (P < 0.001), higher IOP (P = 0.03), higher refractive error (P < 0.01), longer axial length (P = 0.01), CRVE (P < 0.001), lower BMI (P = 0.015), older age (P < 0.001) smaller disc area (P < 0.001) and higher TLCPD (P = 0.03). When age and/or BMI were omitted from the model, reduced RA was also associated with lower CSFP (P < 0.001).

CONCLUSIONS AND RELEVANCE

Reduced RA is associated with narrow CRVE and higher IOP or lower CSFP. The data supports the concurrent role of IOP-related and vascular factors in glaucomatous optic nerve damage.

Telemedicine screening of retinal diseases with a handheld portable non-mydriatic fundus camera

Background

We modified and reconstructed a high image quality portable non-mydriatic fundus camera and compared it with the tabletop fundus camera to evaluate the efficacy of the new camera in detecting retinal diseases.

Methods

We designed and built a novel portable handheld fundus camera with telemedicine system. The image quality of fundus cameras was compared to that of existing commercial tabletop cameras by taking photographs of 364 eyes from the 254 patients. In all 800 fundus images taken by two camera types, 400 images per camera, were graded with the four image clarity classifications.

Results

Using the portable fundus camera, 63% (252/400) images were graded as excellent overall quality, 20.5% (82/400) were good, 11.75% (47/400) were fair, and 4.75% (19/400) were inadequate. Using the tabletop fundus camera, 70.75% (283/400) images were graded as excellent overall quality, 20.4% (51/400) were good, 13.25% (53/400) were fair, and 3.25% (13/400) were inadequate. Common retinal diseases were easily identified from fundus images obtained from the portable fundus camera.

Conclusion

The new type of non-mydriatic portable fundus camera was qualified to have professional quality of fundus images. The revolutionary screening camera provides a foundational platform which can potentially improve the accessibility of retinal screening programmes.