HIGH MYOPIA AND DIABETIC RETINOPATHY: A Contralateral Eye Study in Diabetic Patients With High Myopic Anisometropia

Myopia and Rate of Peripapillary Retinal Nerve Fiber Layer Thickness in Diabetic Patients Without Retinopathy: A 2-Year Longitudinal Study

PURPOSE

The aim of this study was to investigate the association between myopia and longitudinal changes in peripapillary retinal nerve fiber layer (pRNFL) thickness in type 2 diabetic patients without diabetic retinopathy (DR).

METHODS

A total of 1069 participants with a median follow-up time of 1.9 years were included in this study. The participants were categorized into four groups based on the presence of myopia (≤ -0.5 diopter [D]) and diabetes without DR, including a control group (n = 412), diabetes group (n = 416), myopia group (n = 115), and diabetes + myopia group (n = 126). Peripapillary average and sectoral RNFL measurements were obtained using 6 × 6 mm swept-source optical coherence tomography (SS-OCT) scans centered at the optic disc. The change rate of pRNFL, adjusted for age and sex, was calculated and compared among the four groups to investigate the impact of myopia and diabetes.

RESULTS

The baseline estimated pRNFL thickness after adjustment for covariates was 113.7 μm, 116.2 μm, 108.0 μm, and 105.6 μm in the control, diabetes, myopia, and diabetes + myopia group, respectively (diabetes > control > myopia = diabetes + myopia, p < 0.001). The respective average pRNFL loss in the four groups was -0.48 μm/year, -1.11 μm/year, -1.23 μm/year, and -2.62 μm/year (all p < 0.01). The diabetes + myopia group exhibited a greater rate of average pRNFL reduction compared to the other groups (all p < 0.001). Multivariate analysis using a linear mixed-effects model showed that age, diabetes, axial length (AL), and baseline pRNFL thickness were significantly associated with the rate of average pRNFL reduction.

CONCLUSIONS

The diabetes group showed a faster rate of average pRNFL thickness reduction compared to healthy controls, regardless of the presence of myopia. The average pRNFL thickness decreased more rapidly when diabetes and myopia were present simultaneously than in the individual diabetes or myopia group. Both diabetes and myopia were associated with accelerated pRNFL loss.

Macular Choroidal Thickness and Choriocapillaris Vessel Density Alterations in Type 2 Diabetics with High Myopia

INTRODUCTION

The purpose of this study was to investigate the change in macular choroidal thickness and choriocapillaris vessel density in type 2 diabetic (T2D) with high myopia.

METHODS

This cross-sectional study recruited a total of 182 patients (182 eyes) in the Affiliated Hospital of Chengde Medical University between January 2018 and December 2021, including myopia + diabetes patients (40 eyes), T2D patients without myopia patients (47 eyes), myopia patients (45 eyes), and healthy volunteers (50 eyes). The choroidal thickness and choriocapillaris vessel density of macular were measured in all subjects by optical coherence tomography and optical coherence tomography angiography.

RESULTS

The choroidal thicknesses in myopic, diabetes, myopia + diabetes groups were statistically significantly lower than those in control group (p < 0.001). Further pairwise comparisons showed that the choroidal thicknesses in myopia + diabetes group were statistically significantly lower than those in diabetes group (p < 0.001). The choriocapillaris vessel densities in diabetes, myopia + diabetes groups were statistically significantly lower than those in control group (p < 0.001). Interestingly, there were no significant differences in choriocapillaris vessel density between myopia group and control group (p > 0.05). Further pairwise comparisons showed that the choriocapillaris thicknesses in myopia + diabetes group were statistically significantly lower than those in myopia group (p < 0.001), while no statistically significant differences were found between diabetes group and myopia + diabetes group (p > 0.05).

CONCLUSION

The choroidal thickness of the patients with high myopia and diabetes (without diabetic retinopathy [DR]) was significantly lower than that of normal people and diabetic patients, but the choriocapillaris vessel density was not significantly different from that of normal people, which may be one of the protective mechanisms of high myopia against DR.

Clinical Observation of Macular Vessel Density in Type 2 Diabetics with High Myopia

INTRODUCTION

The aim of this study was to compare the macular retinal vessel density (VD) of diabetics with high myopia, diabetics without high myopia, and healthy controls.

METHODS

This cross-sectional study recruited type 2 diabetic (T2D) people with no history of ocular treatment in our hospital. Thirty T2D people with high myopia (30 eyes) were included in group A, while 30 T2D people (30 eyes) without myopia were included in group B. Another 30 healthy volunteers (30 eyes) were included in group C. The superficial and deep capillary plexuses VD of the macula were measured in all subjects by optical coherence tomography angiography. In T2D people with high myopia, the correlation between VD in macular regions and baseline data was investigated.

RESULTS

(1) Overall comparison of the 3 groups: no statistically significant differences in macular central superficial vessel density (SVD) were found in the three groups (p > 0.05). There were significant differences in the temporal, superior, nasal, inferior SVD between the 3 groups (p < 0.05). There were significant differences in macular central, temporal, superior, nasal, and inferior deep vessel density (DVD) between the three groups (p < 0.05). (2) Comparison of B (no myopia, T2D group) and C (healthy control group): inferior SVD in group B was lower than that in group C (p < 0.05). Temporal, superior, nasal, and inferior DVD in group B were lower than those in group C (p < 0.05). (3) A (high myopia group, T2D) compared with B (no myopia, T2D group), A group compared with C (healthy control group): temporal, superior, nasal, inferior SVD and DVD in group A were all lower than those in group B and C (p < 0.05), DVD in group B was lower than those in group C (p < 0.05). (4) The mean SVD and DVD were not correlated with age, IOP, anterior chamber depth, corneal curvature, but they were negatively correlated with axial length and duration of diabetes in the T2D people with high myopia.

CONCLUSION

Myopia and diabetes are two important factors affecting macular retinal VD. Comparing with the eyes of T2D people without high myopia, the VD in macular regions shows a higher decline in the eyes of T2D people with high myopia.

The Association of Axial Length with Macular Microvascular Changes in Chinese Diabetic Retinopathy Patients

Objective

To use optical coherence tomography angiography (OCTA) to compare macular blood flow density, subfoveal choroidal thickness (SFCT) and outer retina thickness (ORT) in non-proliferative diabetic retinopathy (NPDR) patients with different axial length (AL).

Methods

Total 42 patients with NPDR with different eye axis were divided into three groups: group A: 22 mm≤AL<24 mm; group B: 24 mm≤AL<26 mm; group C: AL≥26 mm. Superficial capillary plexus (SCP) in the macular area, vascular length density (VLD) and vascular perfusion density (VPD) in the foveal region, the parafoveal region, the perifoveal region and whole macular region were analyzed. The correlations among axial length, macular microvascular density, SFCT and outer retinal thickness (ORT) were analyzed.

Results

Compared with group A and B, VLD and VPD in group C were significantly lower except the foveal region, and VLD and VPD were negatively correlated with AL. The difference in SFCT among group A, B and C was significant, and SFCT was negatively correlated with AL. Compared with group A, parafoveal ORT in group C was significantly lower than that in group A, and parafoveal ORT was negatively correlated with AL.

Conclusion

In NPDR patients with different AL, macular microvascular density, SFCT, and parafoveal ORT decreased with the increase of AL.

Effect of High Myopia and Cataract Surgery on the Correlation Between Diabetic Retinopathy and Chronic Kidney Disease

PURPOSE

To investigate the effect of high myopia and cataract surgery on the grading of diabetic retinopathy (DR) and their roles in the correlation between DR and chronic kidney disease (CKD).

METHODS

A total of 1,063 eyes of 1,063 diabetic patients were enrolled. We conducted binary and multiple multivariate regressions to analyze the ocular and systemic risk factors of DR. Based on the presence of myopia and history of cataract surgery, we divided the cases into four subgroups, namely those with high myopia, with the history of cataract surgery, with both conditions, and with neither, then determined the correlation between the stages of DR and CKD in each subgroup.

RESULTS

In the binary analysis, high myopia was identified as the protective factor for DR odds ratio (OR): 0.312 [95% confidence interval (CI): 0.195-0.500, p < 0.001], whereas cataract surgery was one of the independent risk factors for DR [OR: 2.818 (95% CI: 1.507-5.273), p = 0.001]. With increased stages of DR, high myopia played an increasingly protective role [mild non-proliferative DR (NPDR), OR = 0.461, p = 0.004; moderate NPDR OR = 0.217, p = 0.003; severe NPDR, OR = 0.221, p = 0.008; proliferative DR (PDR), OR = 0.125, p = 0.001], whereas cataract surgery became a stronger risk factor, especially in PDR (mild NPDR, OR = 1.595, p = 0.259; moderate NPDR, OR = 3.955, p = 0.005; severe NPDR, OR = 6.836, p < 0.001; PDR, OR = 9.756, p < 0.001). The correlation between the stages of DR and CKD in the group with neither high myopia nor cataract surgery history was the highest among all subgroups.

CONCLUSION

High myopia was a protective factor, whereas cataract surgery is a risk factor for DR, and both factors showed stronger effects throughout the (natural disease) grading of DR. The stages of DR and CKD showed a higher correlation after adjustment of the ocular confounding factors.

Refractive Error and Eye Health: An Umbrella Review of Meta-Analyses

Purpose: To explore the associations between refractive errors and multiple eye health outcomes. Methods: This is an umbrella review based on systematic reviews with meta-analyses. In our study, refractive errors included myopia, hyperopia, astigmatism, and anisometropia. We reconducted the meta-analyses whose primary data were available in sufficient detail by random effect model. Heterogeneity was assessed by I ². The main outcomes included myopic macular degeneration (MMD), retinal detachment (RD), cataract, open-angle glaucoma (OAG), strabismus, age-related macular degeneration (AMD), and diabetic retinopathy (DR). Results: Myopia was associated with increased risk of MMD (relative risk = 102.11, 95% CI 52.6-198.22), RD (3.45, 1.08-11.00), nuclear cataract (2.15, 1.53-3.03), posterior subcapsular (PSC) cataract (1.74, 1.41-2.15), OAG (1.95, 1.74-2.19), exotropia (5.23, 2.26-12.09), but decreased risk of DR (0.83, 0.66-1.04), and early AMD (0.80, 0.67-0.94). From mild-to-high myopia, the association strengthened for MMD, RD, nuclear cataract, PSC cataract, OAG, and DR. Hyperopia was associated with an increased risk of early AMD (1.09, 1.01-1.18) and esotropia (22.94, 10.20-51.62). Astigmatism and anisometropia were associated with increased risk of both exotropia and esotropia. Conclusions: Myopia, especially high myopia, demonstrated the highest risk for eye health outcomes, such as MMD, RD, OAG, nuclear and PSC cataracts, and exotropia. However, myopia was associated with a lower risk of early AMD and DR. Individuals with hyperopia are more likely to suffer early AMD and esotropia. Astigmatism and anisometropia predispose to strabismus. A lot of research studies on the mechanism of the associations are needed. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=239744; identifier: 239744.

Calculation of intraocular lens power and to determine the relationship between ocular biometry and severity of diabetic retinopathy in patients with type II diabetes mellitus

Purpose:

To calculate the intraocular lens power and to determine the relationship between ocular biometry and severity of diabetic retinopathy (DR) in patients with type II diabetes mellitus.

Methods:

The study group included 150 type II diabetic subjects with DR. The control group consisted of 150 type II diabetic subjects having no DR. Axial length (AL), corneal power, and anterior chamber depth were measured using LenStar. DR and diabetic macular edema were classified according to International DR Classification. Crystalline lens power was calculated using Barrett Universal II formula. AL to corneal radius ratio was calculated. Chi-square test was used for categorical variables.

Results:

In multivariate logistic models adjusting for age, sex, glycosylated hemoglobin, duration of diabetes, Mean age of patients in the study group was 62.45 ± 4.85 years, whereas in the control group, it was 63.37 ± 7.29 years. Of the eyes with DR, 117, 76, 69, and 38 had mild NPDR, moderate NPDR, severe NPDR, and PDR, respectively. The difference in the mean duration of diabetes mellitus and glycosylated hemoglobin in both study and control groups was found to be statistically significant. A progressive decrease in the mean AL and the anterior chamber depth was observed with increasing severity of DR, and difference was statistically significant. There was a progressive increase in intraocular lens power with increasing severity of DR, and difference was found to be statistically significant.

Conclusion:

In persons with diabetes mellitus, globe elongation plays quite an important role in protective effects against DR, with contribution from intraocular lens power and other refractive components.

Does myopia decrease the risk of diabetic retinopathy in both type-1 and type-2 diabetes mellitus?

Purpose

To study the relationship between the severity of myopia and the severity of diabetic retinopathy (DR) in individuals with type 1 or type 2 diabetes mellitus (DM).

Methods

This retrospective study was conducted using data from electronic medical records from a multicentric eyecare network located in various geographic regions of India. Individuals with type 1 or type 2 DM were classified according to their refractive status. Severe nonproliferative DR (NPDR), PDR, or presence of clinically significant macular edema (CSME) with any type of DR was considered as vision-threatening diabetic retinopathy (VTDR).

Results

A total of 472 individuals with type-1 DM (mean age 41 ± 10 years) and 9341 individuals with type-2 DM (52 ± 9 years) were enrolled. Individuals with a hyperopic refractive error had a significant positive association with the diagnosis of VTDR (odds ratio (OR) 1.26; 95%CI 1.04-1.51, P = 0.01) and moderate nonproliferative DR (OR 1.27; 95%CI 1.02-1.59, P = 0.03) in type-2 DM; however, no significant association was found in type-1 DM. After adjusting for age, gender, anisometropia, and duration of diabetes, the presence of high myopia (< - 6 D) reduced the risk of VTDR in type 2 DM (OR 0.18; 95% CI 0.04-0.77, P = 0.02), but no association was found in type 1 DM. Mild and moderate myopia had no significant association with any forms of DR in both type-1 and type-2 DM.

Conclusion

Hyperopic refractive error was found to increase the risk of VTDR in persons with type 2 DM. High-myopic refractive error is protective for VTDR in type 2 DM, but not in type-1 DM.

Association between ocular biometrical parameters and diabetic retinopathy in Chinese adults with type 2 diabetes mellitus

PURPOSE

The influence of myopia and ocular biometry parameters on diabetic retinopathy (DR) needs further clarification. We aimed to investigate the association between ocular biometrical parameters and DR in Chinese people with diabetes mellitus (DM) without any ocular intervention.

METHODS

This cross-sectional study recruited type 2 DM patients with no history of ocular treatment in Guangzhou, China. The ocular biometrical parameters were obtained by Lenstar (LS900, Haag-Streit AG, Koeniz, Switzerland), including corneal diameter, central corneal thickness (CCT), corneal curvature (CC), anterior chamber depth (ACD), lens thickness (LT) and axial length (AL). The lens power and axial length-to-cornea radius ratio (AL/CR ratio) were calculated. Spherical equivalent (SE) was determined by auto-refraction after pupil dilation. Multivariate logistic regression analyses were performed to explore the associations of ocular biometry with any DR and vision threatening DR (VTDR).

RESULTS

A total of 1838 patients were included in the final analysis, involving 1455 (79.2%) patients without DR and 383(20.8%) patients with DR. After adjusting confounding factors, any DR was independently associated with AL (odds ratio (OR) 0.84 per 1 mm increase, 95% confidence interval (CI): 0.74, 0.94) and AL/CR ratio (OR 0.26 per 1 increase, 95%CI: 0.10, 0.70). Similarly, the presence of VTDR was independently related to AL (OR 0.67 per 1 mm increase, 95%CI: 0.54, 0.85) and AL/CR ratio (OR 0.04 per 1 increase, 95%CI: 0.01, 0.25). The lens power may not be significantly correlated with presence of any DR or VTDR. The CC, corneal diameter and refractive status were not significantly correlated with presence of DR or VTDR.

CONCLUSION

Longer AL and higher AL/CR ratio may be protective factors against the occurrence and progression of DR. Further longitudinal studies are warranted to verify if refractive status and AL-associated parameters contribute to the occurrence and progression of DR in type 2 DM.

Regional analysis of segmented-macular structure in patients with myopic anisometropia

PURPOSE

To compare intraretinal layers between the eyes in patients with myopic anisometropia, and evaluate the relationship between the layers with spherical equivalent (SE) and axial length (AL).

METHODS

In this retrospective study, the more myopic (MM) and fellow (F) eyes of 41 patients with myopic anisometropia, and 38 emmetropic (± 0.50 diopter) control (C) eyes were inclueded. Intraretinal layer segmentation was performed by optical coherence tomography. Global volumes of retinal layers and their thicknesses in nine macular regions were compared. Correlation analysis was used to determine the relationship with SE and AL in each layer.

RESULTS

Total retinal, ganglion cell (GCL), inner nuclear (INL), and outer plexiform (OPL) layer volumes in MM eyes were less than in C eyes, while INL and OPL were less than in F eyes. There was no difference in the fovea, except for the retinal pigment epithelium. In MM eyes, only INL and OPL were thin in at least one perifoveal and parafoveal quadrant compared to F eyes. Only INL and OPL thicknesses were significantly correlated with both SE and AL in all perifoveal quadrants. In contrast to the thinning found in MM eyes, the only layer in which thickening was detected to compare to C eye was nerve fiber layer (NFL), which correlated positively with SE and negatively with AL.

CONCLUSION

While the fovea is less affected by myopia, thinning becomes remarkable in the perifoveal quadrants. Despite thinning in many layers, especially INL and OPL, NFL thickening may be seen due to myopia.

A comparative study of orthokeratology and low-dose atropine for the treatment of anisomyopia in children

Myopic anisometropia (anisomyopia) is a specific type of refractive error that may cause fusion impairment, asthenopia, and aniseikonia. It is sometimes severe enough to reduce the quality of life. Several studies have investigated the treatment effects of orthokeratology (Ortho-K) and topical atropine on anisomyopia control. However, no study has compared these two interventions simultaneously until now. The cohort of this retrospective study included 124 children with anisomyopia who were treated with binocular Ortho-K lenses, 0.01% atropine, or 0.05% atropine. After a 2-year follow-up, the inter-eye difference in axial length (AL) significantly decreased in the Ortho-K group (P = 0.015) and remained stable in the two atropine groups. When comparing the myopia control effect, the use of Ortho-K lenses resulted in an obviously smaller change in AL than the use of 0.01% and 0.05% atropine (P < 0.01). Ortho-K treatment may reduce the degree of anisomyopia and stabilise the progression of myopia. Hence, Ortho-K might be a better choice for anisomyopic children.

Refractive Errors, Ocular Biometry and Diabetic Retinopathy: A Comprehensive Review

Purpose: To summarize the association between diabetic retinopathy and refractory status as well as ocular biometric parameters; To review the theories of the protective effect of high myopia against diabetic retinopathy. Methods: A comprehensive literature search on MEDLINE, EMBASE, Web of Science and Scopus databases as well as reference list search, and systematic review of relevant publications.  Results: Myopia may delay the onset and progression of diabetic retinopathy. Increased axial length in myopia is associated with reduced risk of any diabetic retinopathy and vision-threatening diabetic retinopathy. The possible mechanisms for the protective effect of myopia against diabetic retinopathy may include posterior vitreous detachment, change in retinal blood flow and oxygen demand, choroidal thinning and altered cytokine profiles.  Conclusions: High myopia may be a protective factor against the onset and progression of diabetic retinopathy. Further studies about the mechanisms of how myopia, axial length and ocular biometrics influence the onset and progression of DR are needed.

High myopia is protective against diabetic retinopathy via thinning retinal vein: A report from Fushun Diabetic Retinopathy Cohort Study (FS-DIRECT)

PURPOSE

To investigate the association between high myopia and diabetic retinopathy, and its possible mechanism, in a northeastern Chinese population with type 2 diabetic mellitus.

METHODS

Patients were included from Fushun Diabetic Retinopathy Cohort Study. High myopia was defined as spherical equivalent of autorefraction less than -5D.

RESULTS

A total of 1817 patients [688 (37.9%) diabetic retinopathy, 102 (5.6%) high myopia] were included. Compared to eyes without high myopia, the frequency of diabetic retinopathy and non-proliferative diabetic retinopathy was significantly less in eyes with high myopia (23.5% vs 38.7%, p = 0.002; 22.5% vs 35.3%, p = 0.005). Eyes with high myopia were less likely to have diabetic retinopathy (multivariate odds ratio, 95% confidence interval: 0.39, 0.22-0.68) or non-proliferative diabetic retinopathy (odds ratio, 95% confidence interval: 0.40, 0.23-0.70). High myopia was negatively associated with central retinal venular equivalent (multivariate β, 95% confidence interval: -37.1, -42.3 to -31.8, p < 0.001). Furthermore, central retinal venular equivalent (per 10 μm increase) had a significant association with diabetic retinopathy (odds ratio, 95% confidence interval: 1.24, 1.17-1.31) as well as non-proliferative diabetic retinopathy (odds ratio, 95% confidence interval: 1.24, 1.18-1.31).

CONCLUSIONS

High myopia was negatively associated with both diabetic retinopathy and non-proliferative diabetic retinopathy in this northeastern Chinese population. This protective effect may have been partially achieved via thinning retinal veins.

Characterization of the Three Distinct Retinal Capillary Plexuses Using Optical Coherence Tomography Angiography in Myopic Eyes

Purpose

To segment and quantify three distinct retinal capillary plexuses using optical coherence tomography angiography (OCTA) in myopic eyes.

Methods

We analyzed 96 eyes from 62 subjects with myopia (27.76 ± 7.05 years of age) and evaluated 30 normal eyes from 15 subjects (28.33 ± 3.13 years of age) for controls. En face OCTA images generated by AngioPlex (Carl Zeiss; Oberkochen, Germany) were manually segmented by the progressive matching method into superficial, middle, and deep capillary plexuses (SCPs, MCPs, and DCPs, respectively). Estimated positions for each plexus relative to the reference line were calculated. After strict artifact removal and magnification correction, vessel density (VD) and skeleton density (SD) analyses were performed on each capillary plexus.

Results

Myopic eyes were divided into three groups according to their degree of myopia. We defined the relative estimated positions of the MCP outer boundary to the retinal pigment epithelium fit layer as MCP = –89.317 – 0.178 (central retinal thickness) – 0.580 (ganglion cell inner plexiform thickness); the DCP outer boundary was 38.48 ± 6.24 µm below the inner plexiform layer. VDs were significantly higher in the super-high myopia group than in the control and moderate myopia groups for the DCP (all P < 0.05). SDs in the SCPs were significantly lower in the high myopia and super-high myopia groups than in the control groups (all P < 0.001).

Conclusions

With progressive matching, we segmented three capillary plexuses and defined the relative estimated positions of each capillary plexus to the reference line in myopic eyes. The VD of the DCP increased for more myopic eyes.

Translational Relevance

Our study provides a visual method for OCTA image vascular segmentation for myopic eyes.

Relationship Between Aqueous Humor Levels of Cytokines and Axial Length in Patients With Diabetic Retinopathy

PURPOSE

A negative relationship between intraocular vascular endothelial growth factor-A (VEGFA) and axial length was found, which may help explain why myopia with long axial length was a protective factor for development of diabetic retinopathy (DR). The aim of this study is to further assess the relationship between the aqueous humor levels of interlukin (IL)-8, IL-10, VEGFA, vascular adhesion molecule-1 (VCAM-1), basic fibroblast growth factor, VEGFB, and placental growth factor (PLGF) and axial length in eyes with DR.

DESIGN

Retrospective, single-center, unmasked study.

METHODS

Patients with age-related cataract and with/without DR who visited the Department of Ophthalmology at the Affiliated Hospital of Inner Mongolia Medical University were enrolled. The level of IL-8, IL-10, VEGFA, VCAM-1, and basic fibroblast growth factor were measured by cytometric bead array, and VEGFB and PLGF were measured by enzyme-linked immunosorbent assay. Axial length was measured by biometry.

RESULTS

Totally 65 eyes of 65 patients were enrolled, including 14 patients with nonproliferative diabetic retinopathy, 16 patients with proliferative diabetic retinopathy (PDR), and 35 patients with age-related cataract as control. In the nonproliferative diabetic retinopathy group, the aqueous level of PLGF was negatively correlated with axial length (r = -0.576, P = 0.031), whereas the aqueous levels of IL-10 (r = 0.533, P = 0.049) and VCAM-1 (r = 0.566, P = 0.035) were positively correlated with axial length. In the proliferative diabetic retinopathy group, all cytokines did not significantly correlate with axial length.

CONCLUSIONS

Among patients with diabetic retinopathy, we further found that aqueous levels of PLGF were negatively correlated with axial length, whereas VCAM-1 and IL-10 were positively correlated with axial length. These findings may suggest that these cytokines play a role in the development of DR, and further explain the relationship between the axial length and DR.

Is Myopia Associated with the Incidence and Progression of Diabetic Retinopathy?

PURPOSE

We sought to determine the association of refractive error and its associated determinants (axial length [AL], anterior chamber depth, and corneal curvature) with the incidence and progression of diabetic retinopathy (DR).

DESIGN

Population-based cohort study.

METHODS

A total of 1562 eyes of 840 individuals with diabetes and gradable retinal photographs (mean age [SD], 57.0 [8.3] years, 48.2% female) from the Singapore Malay and Indian Eye Studies at baseline (2004-2009) and follow-up (2011-2015) examinations were included in the analyses. Refractive error was calculated as sphere plus half negative cylinder, while AL, anterior chamber depth, and corneal curvature were assessed using optical biometry. Incident DR was defined as having no baseline DR and any DR at follow-up; incident vision-threatening DR as no baseline vision-threatening DR but present at follow-up; and DR progression as an increase in severity at follow-up from at least minimal baseline DR. Eye-specific data and generalized estimating equation models were used to account for between-eye correlation to determine the relationships between the exposures and outcomes, adjusted for traditional DR risk factors.

RESULTS

At follow-up, 164 of 1273 (12.9%) eyes had incident DR, 17 of 1542 (1.1%) eyes had incident vision-threatening DR, and 75 of 269 (27.9%) eyes with baseline DR experienced progression. A longer AL (per millimeter increase) (risk ratio 0.58 [95% confidence interval 0.38-0.88) was associated with a lower risk of incident DR. No other associations were found.

CONCLUSION

Our findings show that a longer AL is protective of incident DR.

Complete Posterior Vitreous Detachment Reduces the Need for Treatment of Diabetic Macular Edema

BACKGROUND AND OBJECTIVE

To evaluate the vitreomacular interface and its relation to treatment burden for diabetic macular edema (DME) in patients without overt vitreomacular traction (VMT).

PATIENTS AND METHODS

A retrospective cohort study of 494 eyes from 274 patients who had macular spectral-domain optical coherence tomography (SD-OCT) and did not have proliferative diabetic retinopathy, DME, or VMT at the initial visit. Posterior vitreous detachment (PVD) was categorized at the initial visit into five stages (0-4) using SD-OCT parameters alone.

RESULTS

Two of 34 eyes (6.9%) presenting with a complete PVD required DME treatment during follow-up, whereas 144 of 460 eyes (31.3%) without a complete PVD at baseline required treatment (P = .001, Chi-squared). After adjusting for age, ethnicity, gender, and HbA1c, complete PVD at baseline was associated with a significant reduction in risk of DME therapy (hazard ratio: 0.18; 95% confidence interval, 0.05-0.73; P = .02).

CONCLUSION

Complete PVD is independently associated with a reduced need for DME treatment. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:e266-e273.].

Protective factors for diabetic retinopathy in Type 2 diabetes mellitus patients: Long duration of no less than 10 years

AIM

To study the factors protecting against diabetic retinopathy (DR) in patients with over a decade-long history of type 2 diabetes mellitus.

METHODS

A total of 490 patients with type 2 diabetes mellitus lasting for ≥10 years were divided into DR and no diabetic retinopathy (no DR) groups. Their basic information was collected, including age, sex, and duration of diabetes mellitus, as well as pertinent laboratory data. Potential correlations between these factors and DR were evaluated using multivariate analysis.

RESULTS

Overall, 208 patients met the diagnostic criteria for DR. Multivariate logistic regression was used to evaluate factors with P < 0.10 after univariate analysis. Age, total bilirubin, and total cholesterol were found to be protective factors against DR. Presence of diabetic kidney disease and diabetic peripheral neuropathy, duration of diabetes mellitus, apolipoprotein B, blood urea nitrogen, and prothrombin time were found to be risk factors for DR.

CONCLUSIONS

We conclude that total cholesterol is a protective factor against DR. Specifically, it was confirmed that high levels of total cholesterol reduce the risk of DR. These findings may provide a basis for new diet and lifestyle guidelines for patients with diabetes mellitus.

Does the scleral encircling band provide a protective effect against the progression of diabetic retinopathy?

AIM

To evaluate the effect of scleral encircling bands on the development and progression of diabetic retinopathy (DR) in diabetic patients.

METHODS

The medical records of diabetic patients who underwent unilateral retinal detachment (RD) surgery using scleral buckle and encircling band were reviewed retrospectively. Both eyes of patients were included in the study: one eye in each patient had a scleral buckle with encircling band (the operated eye) and the other one is the non-operated eye. The demographic characters, duration of diabetes and period between surgery and the last recall visit were retrieved from each patient. All the cases underwent fundus photo and fluorescein angiography (when indicated) to confirm the DR staging.

RESULTS

Totally 25 patients fulfilled the inclusion and the exclusion criteria were become eligible for the study. A total of 50 eyes of 25 patients were enrolled in this analysis. The mean period of time passed from surgery with encircling band and the last reassessment visit was 12.5±2y. Even though DR could develop in the operated eyes, it was at a less degree of severity compared to the non-operated eyes of same patients (P=0.027).

CONCLUSION

Scleral encircling bands have protective effects against the development and progression of DR.

Pathophysiology of Diabetic Retinopathy: Contribution and Limitations of Laboratory Research

Preclinical models of diabetic retinopathy are indispensable in the drug discovery and development of new therapies. They are, however, imperfect facsimiles of diabetic retinopathy in humans. This chapter discusses the advantages, limitations, and physiological and pathological relevance of preclinical models of diabetic retinopathy. The judicious interpretation and extrapolation of data derived from these models to humans and a correspondingly greater emphasis placed on translational medical research in early-stage clinical trials are essential to more successfully inhibit the development and progression of diabetic retinopathy in the future.

SIGNIFICANT REDUCTION OF BOTH PERIPAPILLARY AND SUBFOVEAL CHOROIDAL THICKNESS AFTER PANRETINAL PHOTOCOAGULATION IN PATIENTS WITH TYPE 2 DIABETES

PURPOSE

To evaluate changes in peripapillary choroidal thickness (PCT) and subfoveal choroidal thickness (SFCT) after panretinal photocoagulation (PRP) for diabetic retinopathy.

METHODS

This retrospective interventional study included 59 treatment-naive eyes of 33 patients who underwent PRP and completed ≥12 months of follow-up. Peripapillary choroidal thickness and SFCT were measured at baseline and 1, 3, 6, and 12 months post-PRP. Differences between baseline and 12 months (ΔSFCT and ΔPCT) and percentage changes (ΔSFCT or ΔPCT/baseline × 100%) were determined.

RESULTS

Mean SFCT was 287.7 ± 76.7 μm (139.0-469.0 μm) at baseline and 225.8 ± 62.0 μm (102.5-379.5 μm) 12 months post-PRP (P < 0.001). Mean PCT was 161.2 ± 16.5 μm (75.3-308.1 μm) at baseline and 128.4 ± 41.8 μm (73.0-212.9 μm) 12 months post-PRP (P < 0.001). ΔSFCT was -61.3 ± 28.7 μm (-139.5 to -17.0 μm), and %SFCT was 21.2 ± 7.2% (6.8% to 36.1%). ΔPCT was -36.4 ± 23.2 μm (-149.1 to 5.4 μm), and %PCT was 22.4 ± 12.0% (2.5% to 62.6%). Diabetic retinopathy severity was the only factor significantly correlated with %SFCT (β = 0.500, P = 0.004) and %PCT (β = 0.152, P = 0.024).

CONCLUSION

Both PCT and SFCT reduced significantly after PRP. Diabetic retinopathy severity was significantly correlated with post-PRP changes of peripapillary and SFCT.

Epigenetically dysregulated genes and pathways implicated in the pathogenesis of non-syndromic high myopia

Myopia, commonly referred to as nearsightedness, is one of the most common causes of visual disability throughout the world. It affects more people worldwide than any other chronic visual impairment condition. Although the prevalence varies among various ethnic groups, the incidence of myopia is increasing in all populations across globe. Thus, it is considered a pressing public health problem. Both genetics and environment play a role in development of myopia. To elucidate the epigenetic mechanism(s) underlying the pathophysiology of high-myopia, we conducted methylation profiling in 18 cases and 18 matched controls (aged 4–12 years), using Illumina MethylationEPIC BeadChips array. The degree of myopia was variable among subjects, ranging from −6 to −15D. We identified 1541 hypermethylated CpGs, representing 1745 genes (2.0-fold or higher) (false discovery rate (FDR) p ≤ 0.05), multiple CpGs were p < 5 × 10⁻⁸ with a receiver operating characteristic area under the curve (ROC-AUC) ≥ 0.75 in high-myopia subjects compared to controls. Among these, 48 CpGs had excellent correlation (AUC ≥ 0.90). Herein, we present the first genome-wide DNA methylation analysis in a unique high-myopia cohort, showing extensive and discrete methylation changes relative to controls. The genes we identified hold significant potential as targets for novel therapeutic intervention either alone, or in combination.

The effect of transient glare on shape discrimination threshold in myopic adults

BACKGROUND

The aim was to evaluate the effect of transient glare on shape discrimination threshold (SDT) in myopic adults.

METHODS

A total of 162 myopic subjects were enrolled. Of these, 121 had low to mid myopia (-1.00 D to -6.00 D) and 41 had high myopia (-6.13 D to -10.25 D). All subjects had corrected visual acuity of 6/6 or better, and only data for the right eye were included in the study. SDTs were measured with circular D4 (fourth derivative of Gaussian) radial frequency patterns with a radial frequency of four, peak spatial frequency of three cpds, and mean radius of 1.5 degrees. SDTs were measured under two conditions, with and without the presence of transient glare while the stimulus was displayed (duration = 500 ms).

RESULTS

Without transient glare, SDTs were not different between the low-mid (23.84 ± 6.02 arcsec) and high myopia groups (25.17 ± 5.98 arcsec, p = 0.16, Mann-Whitney test). With transient glare, SDTs in all subjects became significantly higher (p < 0.001, Wilcoxon signed-rank test). SDTs in the high myopia group (55.53 ± 18.59 arcsec) became significantly higher than those in the low to mid myopia group (47.55 ± 15.06 arcsec, p = 0.014, Mann-Whitney test). The increments were significantly higher in the high myopia group (28.94 arcsec versus 20.88 arcsec, p = 0.031, Mann-Whitney test). Multiple regression showed that SDTs with glare were significantly associated with SDTs without glare (p < 0.001) and the presence of high myopia (p = 0.015).

CONCLUSIONS

Transient glare significantly increased SDTs in all myopic subjects, with the increment in subjects with high myopia being significantly larger than those in subjects with low to mid myopia.