The prevalence of myopia remains stable under tighter COVID-19 social restriction in preschoolers receiving a school-based eyecare program.

PURPOSE: This study investigated the impact of different levels of COVID-19 social restrictions (social distancing in 2020, large-scale home confinement in 2021) on myopia prevalence and behaviours in a preschool population with school-based eyecare programme. METHODS: Repeated cross-sectional surveys were conducted between August and December in 2019, 2020 and 2021. Children aged 5-6 years received ocular examinations, and questionnaires were answered by caregivers before the day of the examination. The main outcome measures were the changes in after-school time spent on homework, screen-based devices and outdoors. Secondary outcome was the change in myopia prevalence (spherical equivalent [SE] ≤ -0.5 D in either eye after cycloplegia). RESULTS: A total of 9997 preschoolers were included in the analysis. Under tighter restrictions, more preschoolers spent ≥1 h/day on screen-based devices (42.8% in 2019, 45.2% in 2020, 48.9% in 2021, p < 0.001), and fewer preschoolers spent ≥30 min/day on after-school outdoor activities (49.5% in 2019, 46.0% in 2020, 41.0% in 2021, p < 0.001) on weekdays. A similar trend was found on weekends. While more preschoolers spent ≥2 h/day on screen-based devices (35.3% in 2019, 38.5% in 2020, 43.0% in 2021, p < 0.001), fewer preschoolers spent ≥2 h/day on outdoor activities (41.7% in 2019, 41.7% in 2020, 34.0% in 2021, p < 0.001). The mean SE and myopia prevalence were stable (9.1% in 2019, 10.3% in 2020, 9.4% in 2021, p = 0.707). CONCLUSION: Our study showed dose-dependent effect of social restrictions on near-work and outdoor behaviours at home. The prevalence of myopia did not increase significantly with short-term cessation of school-based eyecare programmes.

Premyopia at Preschool Age: Population-based Evidence of Prevalence and Risk Factors from a Serial Survey in Taiwan.

PURPOSE: Premyopia at a young age carries a great risk of developing early-onset myopia, especially in regions with myopia epidemics, such as the developed areas in East Asia. This study aims to report the prevalence of premyopia and its risk factors in a Taiwan preschool population and lifestyle changes among premyopic preschoolers before and during the Coronavirus Disease 2019 (COVID-19) pandemic. DESIGN: Repeated countywide population-based, cross-sectional study in Yilan County, northeastern Taiwan. PARTICIPANTS: From 2014 to 2020, a total of 23 930 kindergarteners aged 5 to 6 years were identified in the Yilan Myopia Prevention and Vision Improvement Program (YMVIP). Of those, 21 761 (11 335 [52.1%] boys; mean age, 5.15 ± 0.37 years) were included for final analysis. METHODS: Annual kindergarten-based eye examinations and myopia prevention strategies have been conducted since the commencement of the YMVIP in 2014. Refractive error was determined by cycloplegic autorefraction. The data of potential risk factors for myopia were gathered by caregiver-administered questionnaires. MAIN OUTCOME MEASURES: The prevalence of premyopia (spherical equivalent [SE] > -0.5 diopter [D] and ≤ +0.75 D in the eye with less SE value). RESULTS: The prevalence of myopia (SE ≤ -0.5 D), premyopia, and hyperopia (SE > +0.75) was 10.7% (95% confidence interval [CI], 10.3-11.1), 52.0% (95% CI, 51.3-52.7), and 37.3% (95% CI, 36.7-37.9), respectively. Multinomial logistic regression analysis showed that premyopia prevalence was significantly associated with male gender (odds ratio [OR], 1.25; 95% CI, 1.18-1.32), caregiver myopia (OR, 1.46; 95% CI, 1.37-1.56), screen time ≥ 1 hour per weekdays (OR, 1.10; 95% CI, 1.04-1.17), 2-year exposure to myopia prevention strategy (OR, 0.59; 95% CI, 0.54-0.65), and college or higher education level of caregiver (OR, 0.91; 95% CI, 0.85-0.96). Even without large-scale school closure in Taiwan, there was a slight upward trend of increased time spent on screen-based devices during the COVID-19 pandemic. CONCLUSIONS: Our findings showed that premyopia was the most common refractive error in a Taiwan preschool population. Premyopia was also associated with both parental and environmental myopiogenic factors. Longitudinal studies are warranted to examine the lifestyle change and myopic shift of premyopic preschoolers in the postpandemic era.

Prevalence Trend of Myopia after Promoting Eye Care in Preschoolers: A Serial Survey in Taiwan before and during the Coronavirus Disease 2019 Pandemic.

PURPOSE: To report the prevalence of preschool myopia after implementing a policy intervention promoting outdoor activities and the secular trend of myopia before and during the coronavirus disease 2019 (COVID-19) pandemic in a Taiwan preschool population. DESIGN: Repeated countywide population-based, cross-sectional surveys based on the Yilan Myopia Prevention and Vision Improvement Program (YMVIP). PARTICIPANTS: Among 23 930 kindergarteners 5 to 6 years of age from 7 school-year cohorts in Yilan County from 2014 through 2020, a total of 21 761 children (90.9%) were included for analysis. METHODS: Since launching the YMVIP in August 2014, myopia prevention strategies, such as increasing outdoor activities (2 hours/weekday), have been promoted in all kindergartens, and countywide school-based eye examinations, including cycloplegic autorefraction, and caregiver-administered questionnaires have been carried out annually for all participants. MAIN OUTCOME MEASURES: The prevalence of myopia (spherical equivalent, ≤ -0.5 D in either eye) in each of the 7 school-year cohorts of preschoolers 5 to 6 years of age. RESULTS: The prevalence of myopia continuously decreased for 2 years after implementing the YMVIP: 2014 cohort, 15.5% (95% confidence interval [CI], 14.2%-16.8%); 2015 cohort, 13.5% (95% CI, 12.3%-14.7%); and 2016 cohort, 8.4% (95% CI, 7.4%-9.4%). Subsequent cohorts were exposed maximally to these school-based myopia prevention strategies, and the prevalence of myopia remained relatively stable, between 8.5% and 10.3%, even during the COVID-19 pandemic. Multivariate logistic regression analysis showed a dose-dependent association between the duration of exposure to preventive strategies and the prevalence of myopia (up to 1-year YMVIP exposure, odds ratio, 0.86 [95% CI, 0.74-0.99]; up to 2-year YMVIP exposure, odds ratio, 0.56 [95% CI, 0.50-0.63]) after controlling other myopigenic factors. CONCLUSIONS: This population-based evidence showed high prevalence of preschool myopia and an L-shaped decline after introducing strategies to promote outdoor activities in kindergartens. With undisrupted school-based preventive strategies, the prevalence of myopia can be kept stable, even during the COVID-19 pandemic.

Viral delivery of heme oxygenase-1 attenuates photoreceptor apoptosis in an experimental model of retinal detachment.

This study was designed to evaluate the efficacy of subretinal injection of recombinant adeno-associated virus vector expressing heme oxygenase-1 (rAAV-HO-1) in attenuating photoreceptor apoptosis induced by experimental retinal detachment (RD) in Sprague-Dawley rats. Our results disclosed that subretinal rAAV-HO-1 delivery achieved localized high HO-1 gene expression in retinal outer nuclear layer (ONL) compared with rAAV-lacZ-injected eyes and eyes with RD left untreated both at 2 (p=0.003) and 28 (p=0.007) days of RD. The ONL thickness (p=0.018) and mean photoreceptor nuclei count (p=0.009) in eyes receiving rAAV-HO-1 injection was significantly higher than in rAAV-lacZ-injected or eyes with RD left untreated at 28 days of RD. There were fewer apoptotic photoreceptor nuclei at 2 (p=0.008) and 5 (p=0.018) days of RD and less activated caspase-3 expression (p=0.008) at 2 days of RD in rAAV-HO-1 treated eyes than in control eyes. These data supported that gene transfer approach might attenuate photoreceptor apoptosis caused by RD with a resultant better ONL preservation.

Reduction of experimental diabetic vascular leakage by delivery of angiostatin with a recombinant adeno-associated virus vector.

PURPOSE: To evaluate the efficacy of recombinant adeno-associated virus (rAAV) vector expressing mouse angiostatin (Kringle domains 1 to 4) in reducing retinal vascular leakage in an experimental diabetic rat model. METHODS: rAAV-angiostatin was delivered by intravitreal injection to the right eyes of Sprague-Dawley rats. As a control, the contralateral eye received an intravitreal injection of rAAV-lacZ. Gene delivery was confirmed by reverse-transcriptase polymerase chain reaction (RT-PCR). Diabetes was induced by intravenous injection of streptozotocin (STZ). Vascular permeability changes were evaluated by extravascular albumin accumulation and leakage of intravenous-injected fluorescein isothiocynate-bovine serum albumin (FITC-BSA). Effects of rAAV-angiostatin on expression of vascular endothelial growth factor (VEGF), pigment epithelium-derived factor (PEDF), occludin, and phospho-p42/p44 MAP kinase in retina tissue were analyzed by western blotting. RESULTS: The rAAV-angiostatin injections led to sustained angiostatin gene expression in retina as confirmed by RT-PCR, and reduced extravascular albumin accumulation in STZ-induced diabetic retina. Further, rAAV-angiostatin significantly decreased intravascularly injected FITC-BSA leakage at 5 days (p=0.001), 10 days (p<0.001), and 15 days (p=0.001) after STZ-induced diabetes, as compared to the control eyes receiving rAAV-lacZ. Expression of VEGF and phosphorylation of p42/p44 MAP kinase in retina was reduced by rAAV-angiostatin at day 1 (p=0.043 for both VEGF and phospho-p42/p44 MAP kinase) after STZ-induced diabetes compared with rAAV-lacZ eyes. rAAV-angiostatin reduced retinal occludin loss at 10 days after STZ-induced diabetes (n=5, p=0.041). There was no significant difference in retinal PEDF expression between eyes injected with rAAV-angiostatin and rAAV-lacZ. CONCLUSIONS: Intravitreal delivery of rAAV-angiostatin reduces vascular leakage in an STZ-induced diabetic model. This effect is associated with a reduction in the retinal occludin loss induced by diabetes and downregulation of retinal VEGF and phosphor-p42/p44 MAP kinase expression. This gene transfer approach may reduce diabetic macular edema, providing protection in diabetic patients at risk for macular edema.

Assessing the natural course of diabetic retinopathy: a population-based study in Kinmen, Taiwan.

PURPOSE: To explore the natural course of diabetic retinopathy among type 2 diabetics using the indirect ophthalmoscope and single-field fundus photographs in Kinmen, Taiwan. METHODS: A screening program for diabetic retinopathy was carried out by a panel of ophthalmologists, who employed the ophthalmoscope and 45-degree retinal color photographs to examine the fundus after pupil dilation. Screening, which was conducted between 1999 and 2002, involved 971 patients diagnosed with type 2 diabetes. A multi-state Markov model was used to assess the natural course of diabetic retinopathy among type 2 diabetics. RESULTS: Among the 725 diabetes patients who attended at least two ophthalmological fundus check-ups and were screened, the overall response rate was about 75%. The mean duration of the disease states mild nonproliferative diabetic retinopathy, moderate nonproliferative diabetic retinopathy, severe nonproliferative diabetic retinopathy, and proliferative diabetic retinopathy were 4.05 [95% confidence interval (CI): 3.28-5.32], 4.18 (95% CI: 3.18-6.06), 2.52 (95% CI: 1.78-4.27), and 4.22 (95% CI: 2.88-7.81) years, respectively. Compared to controls, the incidence of blindness reduction for annual, biennial, 3-year, 4-year, and 5-year screenings of diabetic retinopathy were approximately 94.4% (95% CI: 91.6%-96.3%), 83.9% (95% CI: 83.6%-84.2%), 70.2% (95% CI: 69.8%-70.7%), 57.2% (95% CI: 56.7%-57.7%), and 45.6% (95% CI: 45.0%-46.1%), respectively. CONCLUSIONS: In conclusion, the average time for the development of diabetic retinopathy from nonexistence to blindness was approximately 26.5 years. The present recommendation for annual screening in type 2 diabetics with nonproliferative diabetic retinopathy should be retained only for the mild form, not for the moderate or severe forms.

Photodynamic therapy for subfoveal choroidal neovascularization secondary to age-related macular degeneration.

BACKGROUND: To evaluate the safety and efficacy of verteporfin photodynamic therapy (PDT) in patients with subfoveal choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD). METHODS: We retrospectively reviewed the chart records and fluorescein angiography of patients with subfoveal CNV who were treated with verteporfin PDT between September 2001 and March 2003 and who completed at least 1 year of follow-up. The primary efficacy outcomes were the proportions of patients whose Snellen visual acuities had more than 1 line increase, no change or more than 1 line decrease 1 year after study entry compared with their baseline examinations. The secondary efficacy outcome was the changes in the logarithm of the minimum angle of resolution visual acuities at 1-year follow-up. Complications were monitored and tabulated. RESULTS: Forty-eight eyes of 48 patients with subfoveal CNV secondary to AMD were enrolled in this study. The mean follow-up was 12.56 +/- 1.37 months. At their last visit, 10.4% of eyes had more than 1 line improvement in Snellen visual acuity, 72.9% of eyes had no change, and 16.7% experienced more than 1 line of visual acuity loss (7 eyes lost < 3 lines of Snellen visual acuity, 1 eye lost between 3 and 6 lines). None experienced more than 6 lines of visual loss. There was no statistically significant difference between baseline and final visual acuity for eyes with predominantly classic CNV, minimally classic CNV and occult without classic CNV (Wilcoxon Signed Rank test, p = 0.59 ). There was a positive correlation between baseline visual acuity and final visual outcome (Kruskal-Wallis test, p = 0.002). No severe systemic and ocular adverse events were encountered. CONCLUSION: Of our patients with subfoveal CNV secondary to AMD, 83.3% could maintain or improve their visual acuity 1 year after verteporfin PDT. The risk of deterioration in visual acuity due to subfoveal CNV could be reduced by verteporfin PDT. Baseline visual acuity is significantly correlated with the final proportion of visual outcome.

A community-based follow-up study on diabetic retinopathy among type 2 diabetics in Kinmen.

The purpose of this follow-up study was conducted to assess the incidence and risk factors of diabetic retinopathy (DR) among type 2 diabetics in Kinmen, Taiwan. A penal of eye screening regimes were performed yearly for 971 type 2 diabetics by two senior ophthalmologists using indirect ophthalmoscopy and 45-degree color fundus photography to examine fundus after dilating pupils from 1999 to 2002. 74.7% (725/971) of diabetics had been screened at least two times during this period. Among the 548 type 2 diabetics who had no DR at first screening, 93 subjects developed any type of DR. The 3-year 18.2% cumulative incidence was (95% CI: 14.8-21.5%) and incidence density was 6.62% per year (95% CI: 5.36-8.06% per year). Using Cox regression model, HbAlc revealed the significantly dose response relationship to the development of DR (chi2-test for trend = 9.41, p < 0.05) after controlling for confounding factors. Other independent predictors related to the development of DR included duration of diabetes (RR: 1.09, 95% CI: 1.05-1.13), higher systolic blood pressure (>140 vs. < 140 mm Hg, RR: 1.96, 95% CI: 1.23-3.12), and higher triglyceride (> 200 vs. < 200 mg/dl, RR: 1.60, 95% CI: 1.01-2.54). In conclusion, in addition to poor glycemic control of which is the most significant risk factor for the development of DR, longer duration of diabetes, higher systolic blood pressure, and elevated serum triglyceride levels were also associated with the development of DR among type 2 diabetics in Kinmen.