How Does Cataract Surgery Rate Affect Angle-closure Prevalence

Trends in admission rates of primary angle closure diseases for the urban population in China, 2011-2021

Background

Cataract surgery and laser peripheral iridotomy (LPI) are effective approaches for preventing primary angle closure diseases (PACDs), as well as acute primary angle closure (APAC). Due to the development of population screening and increases in cataract surgery rates, this study aimed to examine trends in the admission rates of PACD among the urban population in China.

Methods

This cross-sectional study examined patients who were admitted to a hospital for PACD, and who underwent cataract surgery or LPI operations. The data were obtained from the Yinzhou Regional Health Information Platform (YRHIP) from 2011 to 2021. The annual rates of PACD and APAC admissions, cataract surgery and LPI were analyzed, with the number of cases used as numerators and the annual resident population in Yinzhou district used as denominators.

Results

A total of 2,979 patients with PACD admissions, 1,023 patients with APAC admissions, 53,635 patients who underwent cataract surgery and 16,450 patients who underwent LPI were included. The number of annual admissions for PACD gradually increased from 22 cases (1.6/100000) in 2011 to 387 cases (30.8/100000) in 2016, after which it decreased to 232 cases (16.2/100000) in 2019 and then increased to 505 cases (30.6/100000) in 2021. The number of cataract surgeries gradually increased from 1728 (127.7/100000) in 2011 to 7002 (424.9/100000) in 2021. Similarly, the number of LPI gradually increased from 109 (8.0/100000) in 2011 to 3704 (224.8/100000) in 2021.

Conclusion

The admission rates of PACD for the urban population in China have declined in recent years after a long increasing trend in the rates of cataract surgery and LPI. However, it increased rapidly during the COVID-19 epidemic. The national health database should be further utilized to investigate temporal trends in the prevalence of PACD.

Comparison of Lens Extraction Versus Laser Iridotomy on Anterior Segment, Choroid, and Intraocular Pressure in Primary Angle Closure Using Machine Learning

PRCIS

Treatment strategy of primary angle closure (PAC) is not clear due to the large number of clinical and anatomic-topographic parameters in PAC, influencing the treatment algorithm. Using the machine learning method DD-SIMCA, we justify the expediency of early lens extraction (LE) in PAC.

PURPOSE

To compare the anatomic and functional efficacy of LE and laser peripheral iridotomy (LPI) in patients with PAC using Machine Learning.

MATERIALS AND METHODS

This prospective study included 120 patients aged 41-80 years: 60 eyes with PAC, 30 with PAC suspects, and 30 with healthy eyes (control). Thirty PAC eyes with intraocular pressure (IOP) up to 30 mm Hg were treated using LE with intraocular lens implantation and 30 eyes with LPI. All subjects underwent Swept Source optical coherence tomography. We analyzed 35 parameters of each eye including the lens vault, the choroidal thickness, the anterior chamber angle, and iris specifications such as iris curvature. Considering the correlations between them, the machine learning method DD-SIMCA 1-class classification was applied: the proximity of each sample to the target class (control) was characterized by the total distance to it.

RESULTS

After LE, IOP was significantly lower than after LPI ( P =0). Every third eye with PAC after LE reached the target class: specificity according to DD-SIMCA equals 0.67. This was not observed for the eyes after LPI: specificity equals 1.0. After LE, all parameters of the anterior chamber angle did not differ from the control (all P >0.05). After LPI, there was an increase in anterior chamber depth ( P =0) and a decrease in lens vault ( P =0), but results comparable to the control were achieved only for iris curvature ( P =1.000).

CONCLUSION

The efficacy of LE in PAC is higher than LPI due to the better postoperative anterior chamber topography and lower IOP. This study lends further clinical and anatomic support to the emerging notion of LE as an effective treatment for PAC.

Disease Burden of Glaucoma in China: Findings from the Global Burden of Disease 2019 Study

Purpose

To provide evidence for future strategies in preventing glaucomatous blindness by investigating the disease burden in terms of age, year, and gender from 1990 to 2019 in China.

Methods

The prevalence and disability-adjusted life years (DALYs) of blindness and vision loss due to glaucoma in China were extracted from the Global Burden of Disease (GBD) 2019 study. Age-standardized data is presented in comparison to China’s neighboring countries.

Results

From 1990 to 2019, the prevalent cases and DALYs number with glaucomatous blindness and vision loss increased by 129.53% and 67.29%, respectively. Overall, higher age-standardized prevalence and DALYs rate were detected in males than in females between 1990 and 2019, and people aged 60 to 89 years suffered from a higher DALY number than other age groups in 2019. Among the neighboring countries, China ranked from fourth in 1990 (88.52, 95% uncertainty interval [UI]: 74.62 to 103.24, per 100,000 population) to third in 2019 (71.14, 95% UI: 59.34 to 84.42, per 100,000 population) in age-standardized prevalence while from fourth in 1990 (10.13, 95% UI: 6.68 to 14.46, per 100,000 population) to sixth in 2019 (5.98, 95% UI: 4.14 to 8.42, per 100,000 population) in age-standardized DALYs. Compared with other GBD regions, the largest decrease in age-standardized DALY rate due to glaucoma was found in China (−40.87%, 95% UI: −43.97% to −37.82%). A higher percentage decrease in age-standardized prevalence was also found in China (−19.66%, 95% UI: −22.44% to −17.09%).

Conclusion

Substantial increases in the prevalence of visual impairment and DALYs number of glaucoma were observed from 1990 to 2019. Efforts targeting glaucoma prevention and treatment in China are urgently required, especially for the elderly population and men.

Time trends, associations and prevalence of blindness and vision loss due to glaucoma: an analysis of observational data from the Global Burden of Disease Study 2017

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.