Objective To estimate global prevalence of blindness and vision loss caused by glaucoma, and to evaluate the impact of socioeconomic factors on it. Design A population-based observational study. Setting The prevalence of blindness and vision loss due to glaucoma were obtained from the Global Burden of Disease Study 2017 database. The Human Development Index (HDI), inequality-adjusted HDI and other socioeconomic data were acquired from international open databases. Main outcome measures The prevalence of blindness and vision loss due to glaucoma by age, gender, subregion and Socio-Demographic Index (SDI) levels. Multiple linear regression analysis was performed to explore the associations between the prevalence and socioeconomic indicators. Results The overall age-standardised prevalence of blindness and vision loss due to glaucoma worldwide was 81.5 per 100 000 in 1990 and 75.6 per 100 000 in 2017. In 2017, men had a higher age-standardised prevalence than women (6.07% vs 5.42%), and the worldwide prevalence increased with age, from 0.5 per 100 000 in the 45–49 year age group to 112.9 per 100 000 among those 70+. Eastern Mediterranean and African regions had the highest prevalence during the whole period, while the Americas region had the lowest prevalence. The prevalence was highest in low-SDI and low-income regions while lowest in high-SDI and high-income regions over the past 27 years. Multiple linear regression showed cataract surgery rate (β=−0.01, p=0.009), refractive error prevalence (β=−0.03, p=0.024) and expected years of schooling (β= -8.33, p=0.035) were associated with lower prevalence, while gross national income per capita (β=0.002, p<0.001) was associated with higher prevalence. Conclusions Lower socioeconomic levels and worse access to eyecare services are associated with higher prevalence of glaucoma-related blindness and vision loss. These findings provide evidence for policy-makers that investments in these areas may reduce the burden of the leading cause of irreversible blindness.

To investigate the prevalence and time trends of refractive error (RE) among Chinese children under 18 years old. PubMed, Embase, Web of Science were searched for articles that estimated prevalence of RE in Chinese children. Data of identified eligible studies was extracted by two investigators independently. Pooled prevalence of RE and its 95% confidence interval (95% CI) and the time trends of RE were investigated using Meta-analysis methods. Of the 41 studies covering 1 051 784 subjects, the pooled prevalence of myopia, high myopia, hyperopia and astigmatism in Chinese children was 38.0% (95% confidence interval (CI) = 35.1%-41.1%), 2.8% (95% CI = 2.3%-3.4%), 5.2% (95% CI = 3.1%-8.6%) and 16.5% (95% CI = 12.3%-21.8%), respectively. Subgroup analysis show that children living in urban were at higher risk of RE. Prevalence of myopia and hyperopia were higher in Northern China compared with Southern China and high myopia and astigmatism were higher in Hong Kong, Macau and Taiwan than in mainland China. Regression analysis showed an upward trend in myopia and hyperopia and a downward trend in high myopia and astigmatism with years. The prevalence of RE is higher in urban areas than in rural for Chinese children. The much higher prevalence of myopia and astigmatism in China compared with foreign countries indicates the important role played by environment and genetic factors. Considering the large magnitude of refractive errors, much more attention should still be paid to RE prevention and treatment strategy development in China.

Purpose To investigate the prevalence of myopic macular degeneration (MMD) in the global population. Methods All published literature of population-based studies on MMD prevalence worldwide were searched and only those with clear definitions to diagnose and classify MMD lesions by standardised grading methods were selected. Meta-analysis methods were used to calculate the pooled prevalence of MMD and its 95% CI in a random-effects model. The prevalence of MMD lesions would also be reported, together with the subgroup analysis of age, region and gender. Correlation between MMD prevalence and spherical equivalent levels and axial length were also evaluated. Results 12 studies with 58 558 subjects were included in this meta-analysis. The pooled prevalence of MMD in the world population was 2.1% (95% CI: 1.3% to 3.3%). In the subgroup analysis, people with the following characteristics were at higher risk of developing MMD: female, urban life, living in Asia, older age, longer axial length and severer myopia. Conclusions MMD is a serious public health concern worldwide, particularly in subjects who are women, subjects living in urban areas, subjects living in Asia, and subjects with longer axial lengths and severer myopia. Further studies from other continents/ethnicities are needed for comprehensive estimates of the prevalence of MMD globally.

Background: Although it is widely known that hypertension is an important cause of chronic kidney disease (CKD), little detailed quantitative research exists on the burden of CKD due to hypertension.Objective: The objective of the study is to estimate the global disease burden of CKD due to hypertension and to evaluate the association between the socioeconomic factors and country-level disease burden of CKD due to hypertension.Methods: We extracted the disability-adjusted life-year (DALY) numbers, rates, and age-standardized rates of CKD due to hypertension from the Global Burden of Disease Study 2019 database to investigate the time trends of the burden of CKD due to hypertension from 1990 to 2019. Stepwise multiple linear regression analysis was performed to evaluate the correlations between the age-standardized DALY rate and socioeconomic factors and other related factors obtained from open databases.Results: Globally, from 1990 to 2019, DALY numbers caused by CKD due to hypertension increased by 125.2% [95% confidential interval (CI), 124.6 to 125.7%]. The DALY rate increased by 55.7% (55.3 to 56.0%) to 128.8 (110.9 to 149.2) per 100,000 population, while the age-standardized DALYs per 100,000 population increased by 10.9% (10.3 to 11.5%). In general, males and elderly people tended to have a higher disease burden. The distribution disparity in the burden of CKD due to hypertension varies greatly among countries. In the stepwise multiple linear regression model, inequality-adjusted human development index (IHDI) [β = −161.1 (95% CI −238.1 to −84.2), P < 0.001] and number of physicians per 10,000 people [β = −2.91 (95% CI −4.02 to −1.80), P < 0.001] were significantly negatively correlated with age-standardized DALY rate when adjusted for IHDI, health access and quality (HAQ), number of physicians per 10,000 people, and population with at least some secondary education.Conclusion: Improving the average achievements and equality of distribution in health, education, and income, as well as increasing the number of physicians per 10,000 people could help to reduce the burden of CKD due to hypertension. These findings may provide relevant information toward efforts to optimize health policies aimed at reducing the burden of CKD due to hypertension.

To characterize the morphologic features of corneal parameters and their correlation with axial length (AL) elongation in patients with high axial myopia. Cross-sectional comparative study. A total of 299 eyes with high myopia (299 patients) and 266 eyes of age- and sex-matched control subjects (266 patients) were examined by anterior segment swept-source optical coherence tomography (SS-OCT) and an IOL Master. Central corneal thickness (CCT), thinnest corneal thickness (TCT), corneal volume (CV), and anterior corneal curvature (CC), posterior CC, and total CC were obtained, and their correlation with AL was investigated using multiple linear regression model. The CCT, TCT, CV, and anterior, posterior, and total CC of patients with high myopia were smaller than those of the control subjects. The CCT, TCT, and CV had a continuous downward trend with AL. However, CC decreased rapidly with AL when AL was 28 mm. Multiple linear regression showed that the CCT (β = -1.98, P = .007), TCT (β = -1.63, P = .019), and CV (β = -0.13, P = .001) were associated with AL. Anterior, posterior, and total CCs were negatively associated with AL when AL was <26 mm (all P < .001) and when AL was between 26 and 28 mm (all P < .05). CC decreases may serve as a refractive compensation on myopia when AL is 28 mm. Consideration should be given to the special distribution of cornea curvature for IOL calculations in subjects with high myopia.

Purpose: To investigate the characteristics and factors associated with crystalline lens tilt and decentration measured by CASIA2 anterior segment optical coherence tomography. Setting: Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China. Design: Cross-sectional study. Methods: 1097 eyes of 1097 patients who planned to undergo cataract surgery were enrolled. All patients underwent a general ophthalmologic examination. Lens thickness (LT), front curvature radius (FCR), back curvature radius, lens equator diameter (LED), tilt, and decentration of preoperative crystalline lenses were measured by CASIA2. Univariate and multivariate regression analyses were performed to evaluate the relationships between the tilt and decentration of crystalline lens with related factors. Results: The natural crystalline lenses showed a mean tilt of 5.16 degrees toward the inferotemporal direction and a mean decentration of 0.22 mm toward the temporal direction. Of the total 1097 eyes, 119 eyes (10.85%) had a tilt greater than 7 degrees, and 89 eyes (8.11%) had a decentration more than 0.4 mm. Multivariate regression analysis showed that larger decentration, thicker LT, shorter axial length (AL), and FCR were associated with greater lens tilt (P < .001, P = .007, P = .006, and P = .003, respectively). In addition, greater tilt, older and thinner LT were correlated with larger decentration (all P < .001). Conclusions: Preoperative crystalline lens had a certain degree of tilt and decentration in age-related cataract. The greater tilt of the crystalline lens was, the larger decentration of it was. In addition, AL, FCR, LT, and age also correlated with tilt and decentration.