Prevalence of Vision Impairment in Older Adults in Rural China in 2014 and Comparisons With the 2006 China Nine-Province Survey

Predictors and consequences of visual trajectories in Chinese older population: A growth mixture model

Background

Given the relatively high prevalence of vision impairment and the heterogeneity of visual changes among the elderly population, we aimed to identify the visual trajectories and to examine the predictors and consequences associated with each trajectory class.

Methods

We analysed data from 2235 participants involved in the 5th, 6th, 7th, and 8th waves of the Chinese Longitudinal Healthy Longevity Survey (CLHLS), where vision impairment was evaluated using an adapted Landolt-C chart during each wave. We employed a growth mixture model (GMM) to identify distinct visual trajectories and logistic regression analysis to examine the predictors associated with each trajectory class. Furthermore, we investigated the effect of visual trajectories on distal consequences, including cognitive function, activities of daily living (ADL), instrumental activities of daily living (IADL), depression, anxiety, and fall risk. Within the CLHLS study, cognitive function was assessed using the Chinese version of the Mini-Mental State Examination (CMMSE), ADL via the Katz index, and IADL through a modified version of Lawton's scale. Lastly, depression was assessed using the 10-item version of the Centre for Epidemiologic Studies (CES-D-10), while anxiety was measured using the Generalized Anxiety Disorder scale (GAD-7). Fall risk was determined by asking the question: 'Have you experienced any falls within the past year?'

Results

We identified two distinct visual trajectories in our analysis. Most older adults (n = 1830, 81.9%) initially had a good vision level that diminished ('high-baseline decline' group). Conversely, the remaining participants (n = 405, 18.1%) initially had a lower vision level that improved over time ('low-baseline improvement' group). The 'high-baseline decline' group was more likely to include older adults with relatively higher body mass index (BMI) (odds ratio (OR) = 1.086; 95% confidence interval (CI) = 1.046, 1.127), individuals with higher formal educational qualifications (OR = 1.411; 95% CI = 1.068, 1.864), those current engaging in exercise (OR = 1.376; 95% CI = 1.046, 1.811), and individuals reporting more frequent consumption of fruit (OR = 1.357; 95% CI = 1.053, 1.749). Conversely, the 'low-baseline improvement' group had a higher likelihood of including older individuals (OR = 0.947; 95% CI = 0.934, 0.961), residents of nursing homes (OR = 0.340; 95% CI = 0.116, 0.993) and those self-reporting cataracts (OR = 0.268; 95% CI = 0.183, 0.391) and glaucoma (OR = 0.157; 95% CI = 0.079, 0.315). Furthermore, the 'high-baseline decline' group showed a positive impact on distal consequences, adjusting for sex, birthplace, residence, main occupation, education, economic status, and marital status. This impact included cognitive function (correlation coefficient (β) = 2.092; 95% CI = 1.272, 2.912), ADL (β  = -0.362; 95% CI = -0.615, -0.108), IADL (β  = -1.712; 95% CI = -2.304, -1.121), and reported lower levels of depression (β  = 0.649; 95% CI = 0.013, 1.285). We observed no significant influence on fall risk and anxiety within the identified visual trajectories in the adjusted model.

Conclusions

Vision in older adults with ocular disease could potentially be improved. Having formal education, maintaining an appropriate BMI, engaging in exercise, and consuming fruit more frequently appear to be beneficial for the visual health of the elderly. Considering the negative impact of visual impairment experience on distal cognition, self-care ability, and depression symptoms, stakeholder should prioritise long-term monitoring and management of vision impairment among older adults.

Burden of blindness and vision loss in China over the past 30 years: findings and predictions based on the Global Burden of Disease Study 2019

AIMS

To investigate the burden of blindness and vision loss (BVL) in China over the past 30 years according to year, age and sex, and to estimate future predictions.

METHODS

We analysed the years lived with disability (YLDs), number of cases, age-standardised YLD rates (ASYRs) and age-standardised prevalence rates (ASPRs) of BVL in China from 1990 to 2019. We focused on changes over time using estimated annual percentage changes (EAPCs). Additionally, we used the Bayesian age-period-cohort model to predict the BVL burden from 2020 to 2030.

RESULTS

The number of YLDs and prevalent cases due to BVL increased from 2.57 (95% uncertainty interval (UI) 1.74 to 3.72) and 90.76 million (95% UI 72.21 to 111.92) in 1990 to 5.42 (95% UI 3.61 to 8.02) and 211.67 million (95% UI 168.21 to 259.66) in 2019, respectively. The BVL ASYRs and ASPRs showed a decreasing trend, with EAPCs of -0.13 (95% CI -0.28 to 0.02) and -0.11 (95% CI -0.19 to -0.04), respectively. The elderly and female populations had a higher BVL burden. The numbers of YLDs and cases due to BVL are projected to continue rising to 7.74 and 279.49 million in 2030, respectively. The ASYRs and ASPRs also showed increasing trends.

CONCLUSION

While rates of BVL in China have decreased, there has been a notable increase in the number of YLDs and new cases over the past 30 years. Projections suggest that the burden of BVL will continue to rise over the next 11 years. To address this challenge, appropriate policies must be implemented.

Individual-level socioeconomic status and cataract-induced visual disability among older adults in China: the overview and urban-rural difference

Objective

To investigate the prevalence of cataract-induced visual disability and its association with individual-level socioeconomic status (SES) among older adults in China.

Methods

Using the data of 354,743 older adults (60 years and older) from the Second China National Sample Survey on Disability in 2006. Cross-sectional study design was applied. The differences in visual disability prevalence of cataracts among sociodemographic subgroups were analyzed by the chi-square test, and the association between individual-level SES and cataract-induced visual disability was investigated by the multivariate logistic regression model.

Results

The weighted visual disability prevalence of cataracts was 4.84% in 2006. Older people with a higher household income per capita (OR = 0.83, 95% CI: 0.81-0.85), higher education level (primary school vs. illiteracy: OR = 0.80, 95% CI: 0.76-0.83; ≥undergraduate college vs. illiteracy: OR = 0.31, 95% CI: 0.25-0.39), and occupation (OR = 0.53, 95% CI: 0.50-0.56) were less likely to suffer from cataract-induced visual disability. Household income per capita and education level increase played a greater role in decreasing the risk of visual disability caused by cataracts in urban areas, while having occupation contributed more to reducing the risk of disability in rural areas.

Conclusion

The gap in individual-level SES is closely related to the visual health inequities among older Chinese people and there are two distinct mechanisms in rural and urban areas. Strategies to promote collaborative healthcare development regionally, strengthen safeguards for disadvantaged groups, and increase public awareness of visual disability prevention are warranted.

Six-Year Change in Cataract Surgical Coverage and Postoperative Visual Outcomes in Rural Southern China: The Yangxi Eye Study

PURPOSE

The purpose of this study was to investigate a 6-year change in cataract surgical coverage (CSC), effective cataract surgical coverage (eCSC), and visual outcomes in an elderly population in rural southern China.

DESIGN

This is a prospective population-based study with a 6-year follow-up.

METHODS

The study included rural residents aged 50 years and above in southern China with comprehensive eye examinations at baseline and follow-up in 2014 and 2020, respectively.

RESULTS

Five thousand six hundred thirty-eight participants underwent baseline examinations (mean age 66.1±10.2 y, 50.8% women); and 3141 (64.9%) of 4841 eligible survivors attended the 6-year follow-up. Cataract surgical coverage was 41.7% and 40.6% at baseline and follow-up, respectively, while eCSC were 32.6% and 26.6%. In multivariate models, the 6-year likelihood of cataract surgery decreased with older age [odds ratio (OR)=0.97 per year, 95% confidence interval (CI): 0.94, 0.99, P =0.012] and worse baseline presenting uncorrected visual acuity (PVA) in the worse-seeing eye (OR=0.35 per unit logarithm of the minimum angle of resolution (logMAR), 95% CI: 0.25, 0.48, P <0.001), and increased with prior cataract surgical history at baseline (OR=3.88, 95% CI: 1.91, 7.09, P <0.001). The likelihood of receiving effective cataract surgery decreased with worse baseline PVA in the worse eye (OR=0.49 per unit logMAR, 95% CI: 0.24, 0.97, P =0.042) and better-seeing eye (OR=0.68 per unit logMAR, 95% CI: 0.48, 0.95, P =0.026). Posterior capsular opacification was the main reason for PVA <6/18, reporting it in logMAR (0.5) in operated eyes (38.4% at baseline; 28.1% at follow-up).

CONCLUSIONS

World Health Organization has established a global target of increasing eCSC by 30% before 2030, but no increase was found in rural southern China between 2014 and 2020, let alone reaching the World Health Organization target of 56.3%. Strategies to improve surgery incidence should focus on older persons and those with worse preoperative PVA.

Glaucoma in rural China (the Rural Epidemiology for Glaucoma in China (REG-China)): a national cross-sectional study

OBJECTIVE

This study aimed to investigate the prevalence of glaucoma with associated factors in the rural populations of 10 provinces in China.

DESIGN

A population-based cross-sectional study.

METHODS

All participants aged 6 years or older from 10 provinces completed visual acuity testing, slit-lamp examination, ophthalmoscopy and non-contact tonometry. Glaucoma suspects underwent fundus photography, Goldmann applanation tonometry, visual field testing and gonioscopy. Glaucoma was determined according to the International Society of Geographical and Epidemiological Ophthalmology classification scheme. Associations of demographics and medical factors with glaucoma were assessed using multiple logistic regression models.

RESULTS

From June 2017 to October 2018, 48 398 of 52 041 participants were included in the final analyses. The age-standardised prevalence of glaucoma was 1.7% (95% CI 1.55% to 1.78%) among the participants older than 6 years, which was 2.1% (95% CI 1.93% to 2.23%) in participants aged over 40 years. The constituent ratios of glaucoma were: 44.4% primary angle-closure glaucoma (PACG), 34.7% primary open-angle glaucoma, 2.6% congenital glaucoma and 18.3% other types of glaucoma. Increasing age, smoking, cerebral stroke, type 2 diabetes, higher education (college or more) and higher personal income were significant risk factors for PACG. The unilateral and bilateral blindness rates in the entire study population were 4.692% and 1.068%, respectively. A family history of glaucoma was a significant risk factor for the prevalence of glaucoma and blindness in at least one eye.

CONCLUSIONS

Rural populations have a high prevalence of glaucoma, which should be included in chronic disease management programmes in China for long-term care.

Regional Disparities in Prevalence and Causes of Visual Impairment and Blindness, Cataract Surgical Coverage and Ocular Findings in Adults 50 Years and Older in Brazil: A Comparative Analysis between Two Population-Based Cross-Sectional Surveys Performed Within a 10-Year Interval

PURPOSE

To investigate disparities in the prevalence and causes of visual impairment and blindness, cataract surgical coverage, and ocular findings in older adults from two Brazilian geo-socio-demographic areas, São Paulo and Parintins cities.

METHODS

Data from two population-based studies including participants 50 years and older from the cities of São Paulo (São Paulo Eye Study - SPES, 2004) and Parintins (Brazilian Amazon Region Eye Survey - BARES, 2014) were aggregated.

RESULTS

A total of 5318 participants (3677 from SPES;1641 from BARES) were included. The prevalence of severe visual impairment (SVI) and blindness were, respectively, 0.74% (0.46-1.02) and 0.77% (0.48-1.05) in SPES and 1.72% (1.09-2.35) and 3.44% (2.55-4.33) in BARES. SVI and blindness were associated with BARES study [OR = 2.27 (1.30-3.95); p = .004 - SVI] [OR:4.07 (2.51-6.60); p < .001- blindness]; and older age [OR = 10.93 (4.20-28.45); p < .001 - SPES; OR = 17.96 (8.75-36.83); p < .001 - BARES] while higher education level was a protective factor [OR = 0.21 (0.05-0.95) - SPES; p = .042; OR = 0.21 (0.05-0.91); p = .037 - BARES]. Cataract was the main cause of bilateral severe visual impairment (25.93% in SPES and 64.29% in BARES) and bilateral blindness (21.43% in SPES and 35.71% in BARES). Cataract surgical coverage was significantly lower in BARES (36.32%) compared to SPES (57.75%).

CONCLUSION

The prevalence of SVI and blindness was three times higher in older adults from the Brazilian Amazon compared to those living in São Paulo city, despite a 10-year interval between the two studies. These disparities should be mitigated by initiatives to promote access to eye care services targeting underprivileged and remote Brazilian areas.

Multidisciplinary Approaches and Community-Based Interventions: Adaptable Strategies for Managing Sensory Impairments in Older Adults

Sensory impairments including hearing and vision loss are becoming increasingly prevalent among older adults worldwide, and are adversely affecting their quality of life, independence and cognitive health. This article focuses on the global rise of sensory impairments in the ageing population and evaluates the efficacy of multidisciplinary interventions for management and prevention, including assistive-technology-based medicine, exercise programs and cognitive strategies. Drawing from a wide range of studies, we emphasize the importance of developing globally adaptable, community-based solutions that not only address the direct challenges posed by sensory impairments but also their broader implications for cognitive decline. Additionally, we highlight the need for continuous international research to fine-tune these interventions, to ensure they are holistic and responsive to the diverse needs of older adults across different regions worldwide.

To investigate the individual and household-level factors influencing the willingness to pay for cataract surgery among patients aged 50 years and older in rural China: a cross-sectional study

OBJECTIVES

To investigate the factors influencing the willingness to pay (WTP) for cataract surgery among patients aged 50 years and older in rural China at both individual and household levels.

DESIGN

A cross-sectional study.

SETTING

The study was conducted in Gansu, China.

PARTICIPANTS

Patients aged ≥50 years who were diagnosed with cataracts indicated for surgery and lived rural in Gansu from October to December 2020 were included in the study.

PRIMARY AND SECONDARY OUTCOME MEASURES

The main study outcome was the patients' WTP for cataract surgery. The association of individual characteristics, knowledge about cataracts, health status and household characteristics with patients' WTP was also evaluated based on the collected data using structured questionnaires.

RESULTS

A total of 324 (85.94%) patients in the study reported that they were willing to pay for their cataract surgery. However, only 179 (47.48%) patients were willing to pay over ¥1000 to cover the cost of cataract surgery under the New Rural Cooperative Medical System (NRCMS). Patients aged 75 years and older were significantly less likely to pay for cataract surgery (p=0.037). Better visual status (p=0.032), self-reported severe poor visual status (p=0.001), higher annual household income (p=0.052) and a higher level of children's education (p=0.076) were significantly more likely to pay for cataract surgery.

CONCLUSIONS

The WTP for cataract surgery in rural China is still insufficient. More than half of patients' WTP for surgery do not cover the cost of cataract surgery after reimbursement by the NRCMS. Both individual and household characteristics contribute to the low WTP for cataract surgery.

Incidence, causes and risk factors of vision loss in rural Southern China: 6-year follow-up of the Yangxi Eye Study

PURPOSE

To report the 6-year incidence, causes and risk factors for vision loss (visual impairment (VI) and blindness), among elderly adults in rural southern China.

METHODS

Population-based, cohort study. Initiated in 2014, the study recruited participants aged 50 and older using random cluster sampling from Yangxi County. All eligible participants were invited to attend interviews and comprehensive eye examinations at the 6-year follow-up between November 2020 and March 2021. The WHO categories of vision loss were used to define incident cases of VI (3/60≤VA <6/12), moderate-to-severe VI (MSVI) (3/60≤VA<6/18) and blindness (VA <3/60) in the better-seeing eye.

RESULTS

Among the 5825 baseline participants, 3187 (64.4%) of 4946 surviving subjects participated in the 6-year follow-up. Based on presenting and best-corrected VA, respectively, the crude incidence rate of blindness was 0.8% (95% CI 0.5% to 1.1%) vs 0.3% (95% CI 0.1% to 0.5%), for MSVI 6.7% (95% CI 5.7% to 7.6%) vs 4.6% (95% CI 3.8% to 5.4%) and for any VI 16.1% (95% CI 14.5% to 17.6%) vs 12.9% (95% CI 11.6% to 14.1%). Cataract (48.3%) and refractive errors (44.4%) were the most common causes of vision loss. Factors significantly associated with greater incident vision loss were older age, female sex, less education, living alone and longer axial length (all p<0.05).

CONCLUSIONS

Substantial work is still required to reduce avoidable vision loss in rural China. Screening outreach and efforts to improve awareness which target the poorer and less educated are urgently needed to reduce the growing unmet need for eye care due to ageing.

Attitudes toward ophthalmology as a prospective career among pre-clinical medical students in China

BACKGROUND

A questionnaire was developed and administered to 450 medical students at the Xiangya Medical College, Central South University in Changsha, China to understand the attitudes among medical students in China toward different medical specialties and to find the factors that influenced their choice of career in ophthalmology.

PARTICIPANTS

Fourth-year medical students in the five-year program and sixth-year medical students in the eight-year program.

METHODS

All the students were asked to rate the importance of nine possible factors in choosing a specialty as their vocation and their first ranked future specialty career choice.

RESULTS

When asked about the reasons for choosing to go to medical school, the top four reasons are the ability to help patients, interesting and challenging work, prestige, and job stability. When asked about the reasons for choosing a specialty, the top four reasons are the ability to find employment, financial reward, career upward mobility, and professional pressure. About the first career choice of the future specialty, for clinical medicine students, ophthalmology is the fifth ranked choice for clinical medicine students. 5.6% (five-year) and 3.4% (eight-year) of them choose ophthalmology as their top ranked specialty for their career. For anesthesia medicine and oral medicine students, most of them preferred to choose the same specialty as before. 1.5% (anesthesia) and 4.5% (oral) of them chose ophthalmology as their top ranked specialty.

CONCLUSIONS

Medical students in China have numerous factors that motivate their choice in a specialty. Ophthalmology is the fifth ranked choice among clinical medicine students.

The Association Between Solid Fuel Use and Visual Impairment Among Middle-Aged and Older Chinese Adults: Nationwide Population-Based Cohort Study

BACKGROUND

Indoor air pollution has been reported to have adverse effects on the eye; however, the health effects of exposure to cooking with solid fuels on visual impairment remain unclear in China.

OBJECTIVE

We aimed to examine the association between cooking with solid fuels and visual impairment, including distance visual impairment (DVI) and near visual impairment (NVI).

METHODS

Data were obtained from the China Health and Retirement Longitudinal Study, a nationwide survey of adults aged over 45 years who were enrolled in 2011 (Wave 1) and followed up in Wave 2 (2013), Wave 3 (2015), and Wave 4 (2018). We used Cox proportional hazards models to determine the association between solid fuels use and visual impairment. Additionally, the impact of switching cooking fuel types on vision function were examined through wave-specific data analysis (Wave 1 and Wave 4). Interaction and subgroup analyses were performed to explore the potential effect modifiers. Data were collected using the stratified multistage random sampling method and further analyzed using SPSS 27.0 and R 4.2.1 statistical software packages.

RESULTS

A total of 9559 middle-aged and older Chinese adults without visual impairment at baseline were included in the study, with 51.2% (n=4914) of the participants reporting that they cooked with solid fuels. During the follow-up period, 2644 (27.5%) and 3130 (32.6%) participants developed DVI and NVI, respectively. Compared with the clean fuel users, participants who cooked with solid fuels had a higher risk of DVI (hazards ratio [HR] 1.38, 95% CI 1.28-1.50) and NVI (HR 1.18, 95% CI 1.10-1.27). In addition, switching the cooking fuel type from clean to solid fuels was associated with an elevated risk of DVI (HR 1.51, 95% CI 1.15-1.98) and NVI (HR 1.39, 95% CI 1.06-1.82) compared to persistently using clean fuels during the follow-up period, although no protective effect of switching from solid to clean fuels on NVI was found (P=.52). In subgroup analysis, we found that cooking with solid fuels increased the risk of DVI in participants younger than 65 years (HR 1.41, 95% CI 1.28-1.55), men (HR 1.45, 95% CI 1.28-1.65), urban residents (HR 1.41, 95% CI 1.08-1.75), and smokers (HR 1.43, 95% CI 1.25-1.64). By contrast, negative effects of cooking with solid fuels on NVI were found in nonsmokers (HR 1.21, 95% CI 1.11-1.33) and urban residents (HR 1.20, 95% CI 1.10-1.37).

CONCLUSIONS

Cooking with solid fuels was associated with an increased risk of visual impairment among middle-aged and older Chinese adults. These findings indicate that promoting the utilization of clean fuels is conducive to reducing the burden of visual impairment for the public.

Development and validation of a risk prediction model for visual impairment in older adults

Objectives

This study aimed to determine the risk factors that affect visual impairment in older adults for developing and evaluating a visual impairment risk prediction model.

Methods

In this hospital-based unmatched case-control design study, we enrolled 586 participants (411 in the training set and 175 in the internal test set) from the ophthalmology clinic and physical examination center of a teaching hospital in Liaoning Province, China, from June to December 2020. Visual impairment was defined as best-corrected visual acuity <6/18 (The WHO definition). Possible influencing factors of visual impairment were assessed, including demographic factors, socioeconomic factors, disease and medication factors, and lifestyle. A visual impairment risk prediction model was developed using binary logistic regression analysis. The area under the ROC curve (AUC) was used to evaluate the effectiveness of the proposed prediction model.

Results

Six independent influencing factors of visual impairment in older adults were identified: age, systolic blood pressure, physical activity scores, diabetes, self-reported ocular disease history, and education level. A visual impairment risk prediction model for older adults was developed, showing powerful predictive ability in the training set and internal test set with AUCs of 0.87 (95%CI 0.83-0.90) and 0.81 (95%CI 0.74-0.88), respectively.

Conclusions

The risk prediction model for visual impairment in older adults had high predictive power. Identifying older adults at risk for developing visual impairment can help healthcare workers to adopt appropriate targeted programs for early education and intervention to prevent or delay visual impairment and prevent injuries due to visual impairment in older adults.

Prevalence and predictors of vision impairment among older adults in India: evidence from LASI, 2017-18

BACKGROUND

Older adults experience a natural decline in health, physical and cognitive functionality, and vision impairment (VI) is one among them and has become an increasing health concern worldwide. The present study assessed the association of chronic morbidities such as diabetes, hypertension, stroke, heart diseases and various socioeconomic factors with VI among older Indian adults.

METHODS

Data for this study were derived from the nationally-representative Longitudinal Ageing Study in India (LASI), wave-1 (2017-18). VI was assessed using the cut-off of visual acuity worse than 20/80, and additional analysis was carried out using the definition of VI with a cut-off of visual acuity worse than 20/63. Descriptive statistics along with cross-tabulation were presented in the study. Proportion test was used to evaluate the significance level for sex differentials in VI among older adults. Additionally, multivariable logistic regression analysis was conducted to explore the factors associated with VI among older adults.

RESULTS

About 33.8% of males and 40% of females suffered from VI in India (visual acuity worse than 20/80). Meghalaya (59.5%) had the highest prevalence for VI among older males followed by Arunachal Pradesh (58.4%) and Tripura (45.2%). Additionally, Arunachal Pradesh (77.4%) had the highest prevalence for VI among females followed by Meghalaya (68.8%) and Delhi (56.1%). Among the health factors, stroke [AOR: 1.20; CI: 1.03-1.53] and hypertension [AOR: 1.12; CI: 1.01-1.22] were the significant risk factors for VI among older adults. Additionally, being oldest old [AOR: 1.58; CI: 1.32-1.89] and divorced/separated/deserted/others [AOR: 1.42; CI: 1.08-1.87] were significantly associated with VI. Moreover, older adults with higher educational status [AOR: 0.42; CI: 0.34, 0.52], currently working [AOR: 0.77; CI: 0.67, 0.88], from urban areas [AOR: 0.86; CI: 0.76-0.98] and from western region [AOR: 0.55; CI: 0.48-0.64] had lower odds of VI in this study.

CONCLUSION

This study identified higher rates of VI among those who are diagnosed with hypertension or stroke, currently unmarried, socioeconomically poorer, less educated and urban resident older people that can inform strategies to engage high risk groups. The findings also suggest that specific interventions that promote active aging are required for those who are socioeconomically disadvantaged as well as visually impaired.

Prevalence, Causes, and Risk Factors of Presenting Visual Impairment and Presenting Blindness in Adults Presenting to an Examination Center in Suzhou, China

Purpose

To evaluate the prevalence, causes, and risk factors of presenting visual impairment (PVI) and presenting blindness among adults in Suzhou, China.

Methods

A total of 43927 subjects were included in this cross-sectional study. Each subject underwent ophthalmic examinations, including presenting visual acuity (PVA), intraocular pressure (IOP), slit-lamp examination, and fundus examination under the small pupils of each eye.

Results

Using the World Health Organization (WHO) definition, the prevalence of bilateral PVI, bilateral presenting blindness, monocular PVI, and monocular presenting blindness was 1.59% (95% CI, 1.51-1.67), 0.002% (95% CI, 0.0019-0.0021), 3.87% (95% CI, 3.68-4.06), and 0.19% (95% CI, 0.18-0.20), respectively. Using the United States (US) definition, the prevalence of bilateral PVI, bilateral presenting blindness, monocular PVI, and monocular presenting blindness was 5.83% (95% CI, 5.54-6.12), 0.04% (95% CI, 0.038-0.042), 7.43% (95% CI, 7.06-7.80), and 0.45% (95% CI, 0.43-0.47), respectively. The prevalence of PVI was higher in females (WHO criteria, 2.06%, 95% CI, 1.96-2.16; US criteria, 7.27%, 95% CI, 6.91-7.63) than in males (WHO criteria, 1.2%, 95 CI%, 1.14-1.26; US criteria, 4.65%, 95% CI, 4.42-4.89). The leading cause of PVI is an uncorrected refractive error, followed by cataracts and age-related macular degeneration (AMD). Multivariate analysis proved that the prevalence of visual impairment (PVA, better eye, WHO criteria) increased significantly with older age, higher mean arterial pressure (MAP), higher globulin level, and higher fasting blood glucose (FBG). In addition, it also increased significantly with lower hemoglobin, a lower body mass index (BMI), and a lower arterial stiffness index. In this study, serum creatinine, blood urea nitrogen, uric acid, triglycerides, and the systemic immune-inflammation index (SII) showed no association with visual impairment.

Conclusion

The leading causes of PVI in Suzhou were uncorrected refractive error and cataracts. The prevalence of PVI increased with females, older age, higher MAP, higher FBG, higher globulin, lower hemoglobin, lower BMI, and lower arterial stiffness index.

Prevalence and factors associated with visual impairment in middle-aged and older Chinese population

OBJECTIVE

This study aimed to estimate the prevalence of visual impairment and to identify the factors associated with it in China.

METHODS

Data for this cross-sectional study were retrieved from the China Health and Retirement Longitudinal Study (CHARLS) for a total of 16,480 subjects who completed the questionnaire between June 2011 and March 2012. The prevalence of visual impairment was estimated considering the complex survey design and response rate. Associated factors were identified using the weighted logistic regression analysis.

RESULTS

The overall prevalence of visual impairment among middle-aged and older Chinese adults was 6.22%. Regionally, Qinghai and Gansu provinces showed the highest prevalence of visual impairment, whereas Shanghai showed the lowest prevalence of visual impairment in China. Older age (OR = 1.888; 95% CI: 1.537-2.467) was correlated with a higher likelihood of visual impairment, whereas a non-alcohol intake (OR = 0.072; 95% CI: 0.018-0.246) was correlated with a lower likelihood of visual impairment. Hypertension (OR = 1.299; 95% CI: 1.189-1.467), diabetes (OR = 2.000; 95% CI: 1.163-3.765), lung diseases (OR = 1.795; 95% CI: 1.067-3.019), liver diseases (OR = 1.270; 95% CI: 1.221-2.876), stroke (OR = 1.135; 95% CI: 1.107-3.528), and heart disease (OR = 1.350; 95% CI: 1.104-1.708) were significantly associated with visual impairment.

CONCLUSION

Geographical variations in the prevalence of visual impairment in China were defined, indicating that such variations do exist in China. Age, alcohol intake, hypertension, diabetes, lung diseases, liver diseases, stroke, and heart disease were factors associated with visual impairment.

Contribution of ZBTB20 Polymorphisms to Esophageal Cancer Risk Among the Chinese Han Population

Background

ZBTB20 was overexpressed in esophageal cancer (EC). The study aimed to identify genotypes of ZBTB20 polymorphisms and their correlation with EC occurrence in a Chinese Han population.

Methods

Four single nucleotide polymorphisms (SNPs) in ZBTB20 were randomly selected for genotyping through Agena MassARRAY system among 525 EC patients and 522 healthy controls. Multiple genetic models were applied to assess the association of ZBTB20 polymorphisms with EC susceptibility by calculating odds ratios (ORs) with 95% confidence intervals (CIs).

Results

Rs10934270 was associated with lower EC susceptibility (OR = 0.64, p = 0.004) with statistical power >90% in overall analysis. Specifically, the correlation of rs10934270 with EC susceptibility was found in subgroups including patients with esophageal squamous cell carcinoma (ESCC), males, subjects aged ≤65 years, subjects with BMI ≤ 24 kg/m², and smokers. Rs9841504 might be a risk-increasing factor for ESCC. Moreover, rs9288999 in subjects aged ≤65 years and rs73230612 in females were related to lower EC risk.

Conclusion

Our research is the first to report that ZBTB20 rs10934270 is associated with reduced EC susceptibility in the Chinese Han population. These data provide a scientific basis for understanding the influence of the ZBTB20 gene on EC occurrence.

Visual acuity of urban and rural adults in a coastal province of southern China: the Fujian Eye Study

AIM

To evaluate the vision status and sociodemographic associations of visual acuity (VA) in an urban and rural population in a coastal province of southern China.

METHODS

The Fujian Eye Study, a population-based cross-sectional study, was performed from May 2018 to October 2019. Totally 10 044 participants over 50 years old from all nine cities in Fujian Province were enrolled, and underwent a questionnaire and a series of standard physical and ocular examinations. VA was measured by E Standard Logarithmic Visual Acuity Chart (GB 11533-1989). Data was double entered with EpiData v3.1 for data collation and Stata/SE statistical software v15.1 was used to analyze the data.

RESULTS

Totally 8211 (81.8%) participants were finally included and were divided into urban populations (4678 subjects), rural populations (n=3533), coastal residents (n=6434), and inland residents (1777 subjects); 4836 participants were female. The mean age was 64.39±8.87y (median 64y; range 50-98y). The mean presenting VA was 0.61±0.30 (0.23±0.27 logMAR), and the mean best corrected visual acuity (BCVA) was 0.82±0.28 (0.08±0.19 logMAR). In the multiple regression analysis, BCVA was significantly correlated with several socioeconomic and biologic factors, including age (P<0.001), education level (P<0.001), income (P=0.005), rural residency (P<0.001), inland residency (P=0.001) and refractive error (P<0.001), while sex (P=0.194) was independent with BCVA.

CONCLUSION

Accessible services and eye health policies targeting the elderly, people with high myopia and people living in rural or inland areas are needed.

Trends in the prevalence of vision impairment among the oldest-old Chinese population from 1998 to 2018

Background

Vision impairment has become a prominent public health issue worldwide. However, little is known about vision impairment prevalence trends among the oldest-old adults in China. This study aimed to examine 20-year trends in the prevalence of vision impairment among the oldest-old Chinese adults and explore the contributions of sociodemographic variables, health behaviours, and chronic conditions to the trends.

Methods

This retrospective longitudinal study used data from the Chinese Longitudinal Healthy Longevity Survey during 1998-2018. A total of 45 849 participants aged ≥80 years at study entry were included. Vision impairment was assessed by an adapted Landolt-C chart at each wave. We examined unadjusted and adjusted nonlinear trends using generalized estimating equation models incorporating a natural cubic spline. We conducted linear regression models to estimate absolute annual prevalence changes and determine the contributions of sociodemographic variables, health behaviours, and chronic conditions to the trends.

Results

The fully adjusted prevalence doubled from 5.5% (95% confidence interval (CI) = 5.1%-6.0%) in 1998 to 10.7% (95% CI = 9.9%-11.5%) in 2011 and slightly increased to 11.1% (95% CI = 10.3%-12.0%) in 2018 among the oldest-old Chinese population. Glaucoma, cataracts, cognitive impairment, hearing impairment, and urban residence were significant contributors to changes in vision impairment prevalence during 1998-2018. Differences in vision impairment prevalence associated with glaucoma and cataracts narrowed since 2005. Disparities in the trends among cognitively impaired and unimpaired older adults remained unchanged over time. Similar results were observed in older people with and without hearing impairment.

Conclusions

Vision impairment prevalence among the oldest-old Chinese population increased from 1998 to 2011 and remained stable from 2011 to 2018. Future work is needed to improve the prevention and management of chronic diseases associated with vision impairment to reduce its prevalence.

Prevalence, causes, and impact of self-reported vision impairment among older people in China: Findings from the China health and retirement longitudinal study

This article investigated the prevalence, causes, and impact of self-reported vision impairment among older people in China. A total of 12,910 participants aged ⩾50 years were included in this study from China Health and Retirement Longitudinal Study (CHARLS) over the periods of 2011, 2013, and 2015. All data were reported by participants via a self-reported questionnaire. Distance vision was assessed by asking if they could see the face of a person on the other side of the street. Near vision was assessed by asking if they could read ordinary newspaper. Depressive symptoms were evaluated by 10-item Center for Epidemiological Studies Depression Scale. The analysis method included the χ2 – square distribution test and multiple regression analysis. This article first found that prevalence of self-reported vision impairment was much higher in rural than in urban areas; in urban areas, females had a greater chance of being affected than males, and for both sexes, it increases with increasing age. Second, some factors found are significantly associated with increased vision impairment rates, include increasing age, female gender, rural residents, elementary-level education, unmarried individuals, and non-agricultural occupations. Third, the leading cause of vision impairment was a refractive error and the most common causes of vision impairment include cataracts and glaucoma. Fourth, vision impairment was significantly associated with falls and depressive symptoms and has a negative effect on the quality of life of older Chinese. The article concluded that older people with self-reported vision impairment were relatively low and it is majorly caused by refractive error. Older people with distance vision impairment and near vision impairment were more likely to report falls and depressive symptoms in the future. In line with these findings, a couple of policy recommendations for further research were made.

Distribution and association of visual impairment with myopic maculopathy across age groups among highly myopic eyes - based on the new classification system (ATN)

Purpose

To investigate the percentages and risk factors for visual impairment (VI) across age groups in a highly myopic cohort with a wide range of age (18–93 years).

Methods

A total of 2099 eyes (1220 participants) were enrolled. All participants underwent detailed ocular examinations. Myopic maculopathy (MM) was assessed as myopic atrophy maculopathy (MAM), myopic traction maculopathy (MTM) or myopic neovascular maculopathy (MNM) based on the ATN system.

Results

Most participants younger than 50 years had normal vision, while the cumulative risk of VI and blindness gradually increased after 50–59 years. The percentage of each type of MM increased nonlinearly with ageing (all p < 0.001), with an accelerated period of increase after 45 years for MAM, and after 50 years for MTM and MNM. Axial length (AL) ≥30 mm was the only associated factor for mild VI or worse in participants aged 18–39 years (p < 0.001). Older age, AL ≥30 mm and the presence of MAM were predictors for mild VI or worse in the group aged 40–49 years (all p < 0.05). In participants aged ≥50 years, older age, female sex, longer AL and increased severity of MM were risk factors for VI and blindness (all p < 0.05).

Conclusion

The percentages of MM and related VI increased nonlinearly with older age, with a turning point at 45 years for MAM, preceding that of MTM, MNM and VI by 5 years, warranting future longitudinal studies to confirm. Different age groups presented different risk factors for VI. Timely screening should be in place for middle‐aged high myopes.

The Fujian eye cross sectional study: objectives, design, and general characteristics

Purpose

To describe the objective and design of the Fujian Eye Study and to introduce the general characteristics and vision condition of this study.

Methods

The Fujian Eye Study (FJES) is a population-based cross-sectional survey on the public eye health status of residents over 50 years old in the entire Fujian Province of Southern China, which contains both urban and rural areas and coastal and inland regions. 10,044 participants were enrolled using a two-stage cluster sampling design and underwent a questionnaire and a series of standard examinations both physical and ocular. The main subgroups of data collection included age, sex, region, refractive error, education background, income, eating habits, smartphone usage in the dark, complaints of eye discomfort, history of chronic diseases, consumption of tobacco, alcohol, or tea.

Results

8211 (81.8%) participants were finally included and were divided into urban populations (4678 subjects) and rural populations (3533 subjects) and coastal residents (6434 subjects) and inland residents (1777 subjects); 4836 participants were female. The mean age was 64.39 (SD 8.87) years (median 64 years; range 50–98 years). 227 (3.33%) had vision impairment (VI), 195 (2.87%) had low vision and 14 (0.21%) were blind. The mean presenting near visual acuity (PNVA) was 0.28 (0.17), the mean presenting distance visual acuity (PDVA) was 0.61 (0.30), and the mean best corrected visual acuity (BCVA) was 0.82 (0.28).

Conclusions

The FJES collected detailed questionnaire information and overall ocular and physical examinations, which provide the opportunity to identify risk factors and images of VI and eye diseases and to evaluate their associations with chronic diseases and basic personal information.

Vision impairment, vision correction, and cognitive decline among middle-aged and older Chinese: results from the China health and retirement longitudinal study

OBJECTIVES

To investigate the associations between vision impairment (VI), vision correction (VC), and cognitive function.

METHOD

We included 20,677 participants aged ≥45 years from the China Health and Retirement Longitudinal Study (2011-2015). Participants were grouped into no VI, distance VI (DVI) only, near VI (NVI) only, or both distance and near VI (DNVI), and VI(+)/VC(-), VI(+)/VC(+), VI(-)/VC(-), or VI(-)/VC(+) further at baseline. Cognitive function at baseline and subsequently every two years was applied as a dependent variable in a generalized estimating equation model.

RESULTS

DVI only, NVI only, and DNVI had significantly worse cognitive function over time than no VI (all p < .05). DNVI had significantly worse cognitive function over time than DVI only and NVI only (all p < .001). VI(+)/VC(+), VI(-)/VC(-), and VI(-)/VC(+) had significantly better cognitive function over time than VI(+)/VC(-) (all p < .05). VI(-)/VC(+) had significantly better cognitive function over time than VI(+)/VC(+) and VI(-)/VC(-) (all p < .05).

CONCLUSION

Cognitive function was worse in middle-aged and older Chinese with VI, especially in those with DNVI. VC was associated with better cognitive function over time regardless of the status of vision.

Eye diseases burden in China in the past 30 years

To investigate the national burden of eye diseases in China from 1990 to 2019. The national burden of eye diseases in China, including case numbers, prevalence rate, age-standardized prevalence rate (ASR), disability-adjusted life year (DALY), DALY rate and age-standardized DALY rate (ASD) were calculated and stratified by sex and age. The trends of eye diseases burden from 1990 to 2019 and the correlation between eye diseases burden and human development index (HDI) were analyzed. In 2019, the total case number of eye diseases in China was 0.21 billion, the ASR was 9511/10, the total number of DALY was 4.72 million, and the ASD was 247.4/10. Near vision loss caused the greatest burden, followed by refraction disorders and cataract, with ASD being 73.8/10, 70.3/10 and 59.2/10, respectively. Men had lower risks of eye diseases than women. People aged old and old had the greatest burden of eye diseases. Compared with the year 1990, the total case number increased by 134.6% and DALY by 113.0% in 2019. The ASD of all decreased by 7.5%, and was negatively correlated with national HDI. Near vision loss, refraction disorders and cataract are of heavy disease burden in China. Although the ASD of eye diseases is decreased with the development of the national socioeconomic status, the eye diseases burden in China still increased with population growth and aging.

Health insurance enrollment and vision health in rural China: an epidemiological survey

Background

Vision health is an important aspect of health worldwide. Visual impairment (VI) is associated with poor quality of life and is usually more prevalent in rural areas. To help rural populations obtain vision care, health insurance policies have emerged throughout the world. However, some existing literatures show that health insurance enrollment’s impact on the overall physical health of rural population has been minimal. Focusing on vision health among adults in rural China, our study aims to investigates the impact of health insurance on vision health, heterogeneity of the effect, and the moderating effect of health insurance enrollment on the impact of chronic physical diseases and basic eye diseases on vision health.

Methods

Primary data were collected through a nation-wide epidemiological survey of vision health conducted in rural China in 2018, with a sample size of 28,787 used in our statistical analysis. Instrumental variables regression and Heckman selection models were conducted to examine the impact of health insurance enrollment and reimbursement ratio adults’ vision health outcomes. Subsample regressions by sex, age, education level, and whether with eye diseases were further conducted to explore the heterogeneity in our results. We then examined whether health insurance enrollment moderates the impact of chronic physical diseases and basic eye diseases on vision health through the method of introducing interaction terms.

Results

Participating in health insurance reduced the probability of VI by 2.15 %. The reimbursement rate increasing by 1 % point may reduce the probability of worsening VI by 6.12 %. Men (-0.0235, P = 0.0002) benefit more from insurance enrollment than women (-0.0201, P = 0.0082) with respect to vision health. From the young adult group to the oldest group, the marginal effect of health insurance increased from − 0.0068 (P = 0.0394) to -0.0753 (P < 0.0001). The marginal effect on VI was most significant in people with lower education levels and weakened with increased education levels. People with basic eye diseases (-0.0496, P = 0.0033) benefit more from participating insurance than the people without basic eye diseases (-0.0196, P = 0.0001) with respect to vision health. The moderating effects of health insurance enrollment on the impacts of cerebral infarction (-0.1225, P < 0.0001), diabetes (-0.0398, P = 0.0245), hyperlipidemia (-0.1364, P = 0.0271), mental illness (-0.1873, P = 0.0010), glaucoma (-0.1369, P = 0.0073), diabetic retinopathy (-0.1560, P = 0.0043), and retinal vein obstruction (-0.2018, P = 0.0155) on vision health were significantly negative.

Conclusions

The results suggest that participation in health insurance and higher health insurance reimbursement ratios reduced the risk of VI in the sampled adults. Health insurance has the most significant effect in in vulnerable groups. Heath insurance enrollment moderates the impacts of several chronic physical and basic eye conditions on vision health. Our findings have potential implications for reforming health insurance policies to improve vision health conditions in rural areas of developing countries.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-021-06754-0.

Distribution and determinants of hospital efficiency and relative productivity in county-level hospitals in rural China: an observational study

BACKGROUND

Cataract surgery is very important to prevent blindness, but its productivity and efficiency in China are unknown. Our study aimed to evaluate the geographical distribution of cataract surgeons and prospectively identify the factors associated with the increased productivity in cataract surgery and efficiency in outpatient ophthalmic services in rural Chinese hospitals.

METHODS

Data were prospectively collated from various hospital datasets and the census registered by the geographical unit county. Prior to mapping, the geographical location data of counties were cross-linked with the equivalent ophthalmologist and service output data to create categories and map multiple data attributes. Descriptive statistical analyses were performed to characterise the data stratified by county. Linear regression analyses were used to explore the factors associated with the increased productivity/efficiency.

RESULTS

The ophthalmologists, surgical productivity of ophthalmologists and outpatient efficacy of ophthalmologists significantly varied across counties. During the period between 2016 and 2018, the median (IQR) change in surgical productivity of and outpatient efficacy of ophthalmologists were 31.627 (-3.33 to 29.94) and 118.08 (-132.30 to 740.89). In the simple regression analysis for predictors of a high productivity change, only the increased number of phaco machine had statistical significance (p=0.003). In addition, only the gross domestic product per capita in 2016 was associated with an increased improvement in efficiency of outpatient services (p=0.008).

CONCLUSIONS

This study demonstrated that the ophthalmologist productivity and the efficiency of outpatient services were unequally geographically distributed, and their predictors were identified. Further studies to elucidate the extent of the problem and improve the health service delivery models are required.

Visual trajectories and risk of physical and cognitive impairment among older Chinese adults

BACKGROUND/OBJECTIVES

To identify visual trajectories and examine their relationships with physical and cognitive function in older Chinese adults.

DESIGN

Population-based longitudinal study.

SETTING

The Chinese Longitudinal Healthy Longevity Survey.

PARTICIPANTS

A total of 16,151 participants aged ≥65 years.

MEASUREMENTS

Visual, physical (including activities of daily living [ADL] and instrumental ADL [IADL]), and cognitive function were assessed at baseline and subsequently every 3 years. ADI disability and IADL disability were defined as needing any help in any item of the Katz scale and a modified Lawton's scale, respectively. Cognitive impairment was defined as a Chinese version of the Mini-Mental State Examination score below 24. A group-based trajectory model was used to determine visual trajectories adjusted for age, sex, and education. Associations of visual trajectories with ADL disability, IADL disability, and cognitive impairment were evaluated using generalized estimating equation models adjusted for potential confounders.

RESULTS

This study identified three distinct visual trajectories, including no decline (32.4%), moderate decline (48.3%), and progressive decline (19.3%) during the follow-up period. Compared with the no decline trajectory, both the moderate decline (ADL disability: OR = 2.75, 95% CI: 2.30-3.28; IADL disability: OR = 3.01, 95% CI: 2.74-3.31; cognitive impairment: OR = 3.37, 95% CI: 3.02-3.76) and the progressive decline (ADL disability: OR = 8.50, 95% CI: 6.55-11.02; IADL disability: OR = 12.96, 95% CI: 9.95-16.87; cognitive impairment: OR = 10.84, 95% CI: 8.89-13.23) trajectories were significantly associated with an increased risk of functional impairment. Compared with the moderate decline trajectory, the progressive decline trajectory was significantly associated with an increased risk of ADL disability (OR = 3.09, 95% CI: 2.46-3.89), IADL disability (OR = 4.30, 95% CI: 3.29-5.61), and cognitive impairment (OR = 3.22, 95% CI:2.63-3.93).

CONCLUSION

Older Chinese adults exhibit three distinct visual trajectories and those with decline trajectories in vision have an increased risk of functional impairment than those with a trajectory of no decline in vision.

A Novel Hierarchical Deep Learning Framework for Diagnosing Multiple Visual Impairment Diseases in the Clinical Environment

Early detection and treatment of visual impairment diseases are critical and integral to combating avoidable blindness. To enable this, artificial intelligence–based disease identification approaches are vital for visual impairment diseases, especially for people living in areas with a few ophthalmologists. In this study, we demonstrated the identification of a large variety of visual impairment diseases using a coarse-to-fine approach. We designed a hierarchical deep learning network, which is composed of a family of multi-task & multi-label learning classifiers representing different levels of eye diseases derived from a predefined hierarchical eye disease taxonomy. A multi-level disease–guided loss function was proposed to learn the fine-grained variability of eye disease features. The proposed framework was trained for both ocular surface and retinal images, independently. The training dataset comprised 7,100 clinical images from 1,600 patients with 100 diseases. To show the feasibility of the proposed framework, we demonstrated eye disease identification on the first two levels of the eye disease taxonomy, namely 7 ocular diseases with 4 ocular surface diseases and 3 retinal fundus diseases in level 1 and 17 subclasses with 9 ocular surface diseases and 8 retinal fundus diseases in level 2. The proposed framework is flexible and extensible, which can be inherently trained on more levels with sufficient training data for each subtype diseases (e.g., the 17 classes of level 2 include 100 subtype diseases defined as level 3 diseases). The performance of the proposed framework was evaluated against 40 board-certified ophthalmologists on clinical cases with various visual impairment diseases and showed that the proposed framework had high sensitivity and specificity with the area under the receiver operating characteristic curve ranging from 0.743 to 0.989 in identifying all identified major causes of blindness. Further assessment of 4,670 cases in a tertiary eye center also demonstrated that the proposed framework achieved a high identification accuracy rate for different visual impairment diseases compared with that of human graders in a clinical setting. The proposed hierarchical deep learning framework would improve clinical practice in ophthalmology and broaden the scope of service available, especially for people living in areas with a few ophthalmologists.

Prevalence, Causes, and Factors Associated with Visual Impairment in a Chinese Elderly Population: The Rugao Longevity and Aging Study

Purpose

This study aimed to explore the current prevalence, causes, and factors associated with visual impairment in a Chinese elderly population.

Methods

A random sample of 2164 candidates aged ≥70 years was selected. Among them, 1914 participants (response rate: 88.4%) underwent comprehensive eye examinations. The prevalence and causes of visual impairment were estimated, and the associated factors were identified.

Results

The standardized prevalence of mild visual impairment (<6/12 to ≥6/18), moderate to severe visual impairment (MSVI) (<6/18 to ≥3/60), and blindness (<3/60) in the better eye were 20.5%, 25.8%, and 3.4%, respectively. The leading cause of visual impairment was cataract (49.7%), followed by uncorrected refractive error (26.5%), myopic maculopathy (5.8%), and posterior capsular opacification (5.5%). Optical coherence tomography revealed that vitreoretinal interface abnormalities were the third most common cause of monocular mild visual impairment (2.2%) and MSVI (4.4%) in the elderly population. A large number of patients with visual impairment (81.7%) were amenable to undergo the interventions. Visual impairment was associated with advanced age (odds ratio [OR], 1.09 per year; p<0.001), female sex (OR, 1.59; p=0.003), self-reported visual impairment (OR, 1.91; p<0.001), cognitive impairment (OR, 1.40, p=0.005), and high educational level (OR, 0.75; primary, p=0.045; and OR, 0.53, secondary or higher; p<0.001).

Conclusion

Visual impairment was common in the Chinese elderly population and a severe health and social problem. Practicable policies are urgently needed to popularize eye health knowledge and promote treatments for visual impairment in elderly people in rural China.

Prevalence of visual impairment among older Chinese population: A systematic review and meta-analysis

Background

To evaluate the prevalence of visual impairment (VI) among elderly Chinese population.

Methods

All population-based studies on VI prevalence among elderly Chinese populations were searched and only studies with clear definitions of diagnosis were selected. Meta-analysis methods were used to estimate the pooled prevalence and its 95% confidence interval (95%CI) of moderate and severe visual impairment (MSVI) and blindness both by presenting visual acuity (PVA) and best corrected visual acuity (BCVA). Subgroup analysis of gender, district, geographical location, age, education level and examined year were also conducted.

Results

72 studies with 465 039 individuals were included and analyzed. Using PVA, the pooled prevalence of MSVI is 10.9% (95% CI = 9.4%-12.6%) and blindness is 2.2% (95% CI = 1.8%-2.8%), while prevalence of MSVI and blindness by BCVA was 5.4% (95% CI = 4.6%-6.2%) and 2.2% (95% CI = 1.9%-2.5%), respectively. Females, rural residents, older age and lower educational level were risk factors for MSVI and blindness.

Conclusions

VI causes a great health burden among Chinese populations, particularly affecting female subjects, subjects dwelling in rural area, older subjects and subjects with lower educational level.

Prevalence, Risk Factors, and Causes of Visual Impairment in an Elderly Chinese Uygur Population in Southern Xinjiang

Purpose

To investigate the prevalence, risk factors, and major causes of visual impairment (VI) in an elderly Chinese Uygur population in southern Xinjiang.

Methods

This was a population-based cross-sectional study. Participants aged 50 years and older from Haohan Country, Xinjiang Uygur Autonomous Region, were enrolled from August 2018 to December 2018 using cluster sampling. Participants underwent examinations including presenting visual acuity (PVA), pinhole vision, slit-lamp, intraocular pressure, and direct ophthalmoscopy. Participants' education and demographic information was collected by a questionnaire. The prevalence, risk factors, and major causes of vision loss were evaluated.

Results

A total of 1465 participants (85.4% response rate) were enrolled. The mean age of the subjects was 59.1 ± 9.7 years. The prevalence of mild VI, moderate VI, severe VI, and blindness in the better eye was 13.3%, 12.8%, 2.9%, and 3.4%, respectively. The prevalence of low vision and blindness in this study was higher than that in Altay & Tacheng and Changji in northern Xinjiang, lower than that in Luxi, and similar to that in Tibet. The multiple logistic regression analysis showed that age, education level, and body mass index (BMI) were significantly associated with low vision and blindness (P ≤ 0.001, <0.05, 0.002, respectively). The major causes of low vision were cataract (42.6%), refractive error (19.6%), and glaucoma (12.6%), whereas the primary causes of blindness were cataract (34%), glaucoma (34%), and retinitis pigmentosa (10%).

Conclusions

VI is an important public health issue among elderly Uygur individuals in the area, especially for those with low education levels. Cataract is the leading cause of low vision and blindness.

Burden of vision loss due to diabetic retinopathy in China from 1990 to 2017: findings from the global burden of disease study

PURPOSE

To conduct a detailed analysis on the burden of vision loss due to diabetic retinopathy (DR) by year, age and gender in China from 1990 to 2017.

METHODS

This is a between-country, retrospective, comparative burden-of-disease study. Prevalence and Years Lived with Disability (YLDs) data caused by DR in China and relative territories were extracted from the Global Burden of Disease (GBD) study 2017 to observe the changing trends of vision loss.

RESULTS

Prevalence and YLDs of DR in China increased significantly from 1990 to 2017. The age-standardized prevalence and YLDs rate witnessed a slowly declining trend recently. Higher prevalence and YLDs were observed in female subjects in the past three decades. Middle-aged and elderly people suffered from a higher burden of DR-induced vision loss. The total age-standardized prevalence rate of China in 1990 (17.68) and 2017 (21.88) was lower than that of other seven neighbouring countries. In 2017, moderate vision loss (MVL) (17.19) accounted for the largest proportion in China. The all-age YLDs of DR showed the second-highest increase (150.26%) while the age-standardized YLDs rate showed the third-highest increase (14.91%) among fifteen common causes of vision impairment (VI) from 1990 to 2017. China ranked 3rd among G20 countries in terms of all-age YLDs while ranked 18th in age-standardized YLDs rate in 2017.

CONCLUSIONS

In the past three decades, the prevalence and YLDs due to DR in China have improved in both genders. This study highlights the importance of prevention for DR, especially for women and the elderly.

Prevalence and causes of bilateral visual impairment in rural areas of Tianjin, China - The Tianjin Eye Study

PURPOSE

To estimate the prevalence, causes and risk factors of bilateral visual impairment in rural areas of Tianjin, China.

METHODS

A large population-based, cross-sectional study. A stratified random cluster sampling method was used to investigate 12 233 participants in all age groups living in rural Tianjin. Participants completed questionnaires and received professional ophthalmology examinations.

RESULTS

According to World Health Organization best-corrected visual acuity (BCVA) criteria, the crude prevalence of bilateral visual impairment (BCVA < 20/63), bilateral low vision (BCVA < 20/63 to ≥20/400) and bilateral blindness (BCVA < 20/400) was 2.53%, 2.40% and 0.14% (age- and gender-standardized prevalence was 1.86%, 1.76% and 0.11%). The prevalence increased with age and was higher in women than men. The most common causes of bilateral visual impairment in the total population were cataract (48.39%), refractive error/amblyopia (17.74%), age-related macular degeneration (AMD) (10.00%), diabetic retinopathy (5.81%) and glaucoma (3.87%). For participants younger than 50 years, refractive error/amblyopia was the leading cause of low vision and blindness, while cataract was the major cause in the participants over 50. Female gender, older age and self-reported diabetes were associated with increased risks of visual impairment.

CONCLUSION

The age- and gender-standardized prevalence of low vision, especially in the older group (50+), was higher in this study compared with previous studies in China. Refractive error/amblyopia was the leading cause of bilateral visual impairment in younger group, while cataract was the primary cause in the older group. These findings will provide useful information for planning comprehensive eye healthcare programmes in China.

Self-reported vision impairment, vision correction, and depressive symptoms among middle-aged and older Chinese: Findings from the China health and retirement longitudinal study

OBJECTIVE

To investigate associations between vision impairment (VI), vision correction (VC) and depressive symptoms among middle-aged and older Chinese.

METHODS

22 203 participants aged ≥45 years from China Health and Retirement Longitudinal Study 2011 to 2015 were divided into four self-reported VI categories: no VI, distance VI (DVI) only, near VI (NVI) only, and both distance and near VI (DNVI); and four self-reported VI/VC subgroups: VI(+)/VC(-), VI(+)/VC(+), VI(-)/VC(-) and VI(-)/VC(+). Depressive symptoms were evaluated by 10-item Center for Epidemiological Studies Depression Scale (CESD-10).

RESULTS

Compared with no VI, DVI only (OR = 2.12, 95% CI: 1.95, 2.31), NVI only (OR = 1.51, 95% CI: 1.39, 1.63) and DNVI (OR = 2.75, 95% CI: 2.47, 3.07) were associated with higher odds of depressive symptoms. Compared with VI(+)/VC(-), VI(+)/VC(+) (OR = 0.91, 95% CI: 0.83, 0.98), VI (-)/VC(-) (OR = 0.50, 95% CI: 0.48, 0.53) and VI(-)/VC(+) (OR = 0.49, 95% CI: 0.47, 0.54) were associated with lower odds of depressive symptoms. Compared with no VI at baseline, baseline DNVI was significantly associated with higher odds of depressive symptoms after two (OR = 1.48, 95% CI: 1.16, 1.88) and four (OR = 1.32, 95% CI: 1.04, 1.68) years. Baseline depressive symptoms were significantly associated with higher odds of VI after two (OR = 1.53, 95% CI: 1.34, 1.74) and four (OR = 1.54, 95% CI: 1.34, 1.76) years.

CONCLUSION

Adults with DNVI were more likely to report depressive symptoms in the future and those with depressive symptoms were more likely to report VI in the future. VC might be a protective factor for preventing depressive symptoms among adults with VI.

The Jidong Eye Cohort Study: objectives, design, and baseline characteristics

Background

To describe the objective, design and baseline characteristics of the Jidong Eye Cohort Study (JECS), a community-based cohort in China based on etiology, imaging and biomarkers. The JECS will clarify the pathogenesis of visual impairment and status of ocular indicators in the occurrence and progression of cardio-cerebrovascular and neurological diseases.

Methods

Between August 2019 and January 2020, the JECS recruited consecutive participants aged 18 years and older from the Jidong communities in China. The demographic and clinical characteristics were collected by trained site personnel via face-to-face interviews. The relevant biological samples were also collected. The participants underwent comprehensive ophthalmic examination, such as retinal photography and optical coherence tomography (OCT) angiography. The following outcomes were measured annually: ocular vascular abnormality, optic nerve degeneration, cardiovascular diseases (CVD) and neurological diseases. The study will be performed until 2024.

Results

Among 3377 participants, the average age was 45.0 ± 12.5 years and 1809 (53.6%) were women. Hypertension occurred in 825 individuals (25.0%), diabetes in 258 (7.7%), hyperglycemia in 474 (14.2%), and a CVD history in 100 (3.0%). The mean best-corrected visual acuity was 0.1 logMAR in the recruited subjects. The average OCT signal index was 8.2 ± 1.2. Additionally, the mean vessel densities for the entire measured area were 46.4% and 50.8% for the superficial and deep vascular complex, respectively. Mean area and perimeter of foveal avascular zone was 0.3 mm² and 2.3 mm.

Conclusions

The JECS is a large community-based prospective cohort in North China. Rich data collected from this study will provide the opportunity to identify risk factors, imaging, and biomarkers of visual impairment (either ocular vascular anomalies or optic nerve degeneration) and to evaluate their associations with CVD and neurological diseases.

Prevalence and causes of vision loss in China from 1990 to 2019: findings from the Global Burden of Disease Study 2019

BACKGROUND

Vision loss is an important public health issue in China, but a detailed understanding of national and regional trends in its prevalence and causes, which could inform health policy, has not been available. This study aimed to assess the prevalence, causes, and regional distribution of vision impairment and blindness in China in 1990 and 2019.

METHODS

Data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 were used to estimate the prevalence of moderate and severe vision impairment and blindness in China and compare with other Group of 20 (G20) countries. We used GBD methodology to systematically analyse all available demographic and epidemiological data at the provincial level in China. We compared the age-standardised prevalences across provinces, and the changes in proportion of vision loss attributable to various eye diseases in 1990 and 2019. We used two different counterfactual scenarios with respect to population structure and age-specific prevalence to assess the contribution of population growth and ageing to trends in vision loss.

FINDINGS

In 2019, the age-standardised prevalence was 2·57% (uncertainty interval [UI] 2·28-2·86) for moderate vision impairment, 0·25% (0·22-0·29) for severe vision impairment, and 0·48% (0·43-0·54) for blindness in China, which were all below the global average, but the prevalence of moderate and severe vision impairment had increased more rapidly than in other G20 countries from 1990 to 2019. The prevalence of vision loss increased with age, and the main causes of vision loss varied across age groups. The leading causes of vision impairment in China were uncorrected refractive error, cataract, and macular degeneration in both 1990 and 2019 in the overall population. From 1990 to 2019, the number of people with moderate vision impairment increased by 133·67% (from 19·65 to 45·92 million), those with severe vision impairment increased by 147·14% (from 1·89 to 4·67 million), and those with blindness increased by 64·35% (from 5·29 to 8·69 million); in each case, 20·16% of the increase could be explained by population growth. The contributions to these changes by population ageing were 87·22% for moderate vision impairment, 116·06% for severe vision impairment, and 99·22% for blindness, and the contributions by age-specific prevalence were 26·29% for moderate vision impairment, 10·91% for severe vision impairment, and -55·04% for blindness. The prevalence and specific causes of vision loss differed across provinces.

INTERPRETATION

Although a comprehensive national policy to prevent blindness is in place, public awareness of visual health needs improving, and reducing the prevalence of moderate and severe vision impairment should be prioritised in future work.

FUNDING

China National Key Research and Development Programme and Beijing Municipal Special Funds for Medical Research on Public Welfare Development and Reform.

Frequency of presenting visual acuity and visual impairment in Chinese college students

AIM

To obtain the baseline data on presenting visual acuity (PVA) and evaluate the prevalence and associated factors for visual impairment based on PVA in 9070 Chinese college students.

METHODS

The freshmen at a university in southern China, including 6527 undergraduate students and 2543 graduate students, were investigated for some socio-demographic characteristics and underwent routine medical examination, including measuring PVA, height, and weight. Visual impairment was defined according to the new World Health Organization criteria for blindness and visual impairment.

RESULTS

In 9070 college students, the mean PVA in the better eye was 0.094±0.163 logMAR. The prevalence of visual impairment based on PVA was 2.7%. Only 38.3% college students had normal visual acuity [PVA equal to 0 logMAR (20/20) in both eyes]. There were 69.8% of students wearing spectacles. Logistic regression showed that home region (non-Guangdong provinces, P<0.0001, OR=1.70) was risk factor for visual impairment while BMI (P=0.001, OR=0.92) was protective factor from visual impairment. Ethnicity (Han Chinese, P<0.0001, OR=3.17) was risk factor for wearing spectacles while age (P=0.01, OR=0.90) was protective factor from wearing spectacles.

CONCLUSION

This study provides the baseline data on PVA and the prevalence of visual impairment in Chinese college students. Our analyses reveal that BMI and home region are associated factors for visual impairment based on PVA, while age and ethnicity are associated factors for wearing spectacles.

Willingness to pay for cataract surgery in baiyin district, northwestern China

PURPOSE

To investigate willingness to pay for cataract surgery, and its associations, in Northwestern China.

METHODS

Four hundred thirty-eight persons aged 50 years and above, diagnosed with cataract indicated for surgery, identified in an outreach screening program were included. Subjects were offered a willingness-to-pay interview for the maximal amount that the subjects would be willing to pay for a cataract surgery. Age, gender, literacy, education level, occupation, and annual household income were recorded.

RESULTS

Among 328 (74.9%) subjects who completed the interview, 197 (60.1%) participants were willing to pay something for the cataract surgery (mean, 902.9 ± 856.7 renminbi[RMB], [US$ 145 ± 137]; median, 500RMB, US$ 78). Individuals with presenting visual acuity (PVA) in the worse eye ≤6/60 (OR: 2.1, 95% CI: 1.3-3.2) and a high annual household incomes (OR: 2.0, 95% CI: 0.9-4.6) were likely to be willing to pay for the surgery, as revealed in the regression models. Willingness to pay any amount for cataract surgery was more likely among literate persons (OR: 1.5, 95% CI: 1.0-2.4) and persons with non-agricultural occupation (OR: 1.8, 95% CI: 1.0-3.2).

CONCLUSIONS

The amount that subjects were willing to pay is significantly less than the current cost of cataract surgery (5000 RMB, US$320) in the area. Providing low-cost cataract surgery to patients in a financially sustainable manner is important to increase uptake of cataract surgery among rural residents in Northwest China.

Incidence of ocular conditions associated with perfluoroalkyl substances exposure: Isomers of C8 Health Project in China

The detrimental effects of perfluoroalkyl substances (PFASs) on several physiological systems have been reported, but the association of PFASs with eye, one of the most sensitive and exposed organ, has never been explored. To investigate the association between eye diseases including visual impairment (VI) and PFASs isomers, a cross-sectional stratified study was conducted in 1202 Chinese population, aged 22-96 years, from Shenyang, China. A standard protocol including Snellen vision chart, slit-lamp microscopy and direct ophthalmoscopy was used to examine eye diseases/conditions relating to anterior and posterior segment of eyes. In addition, we measured the blood concentrations of 19 linear and branched PFASs at one-time point. Results indicated that blood levels of PFASs were significantly higher in eye disease group than normal group. PFASs exposure were positively associated with both combined eye diseases and individual eye diseases. Among other PFASs, linear perfluorooctane sulfonate (n-PFOS; odds ratio [OR] = 3.37, 95% confidence interval [CI]: 2.50, 4.56), branched perfluorooctane sulfonate (Br-PFOS; OR = 2.25, 95% CI: 1.72, 2.93) and linear perfluorooctanoic acid (n-PFOA; OR = 1.79, 95% CI: 1.36, 2.37) significantly increases the odds of VI. Vitreous disorder was adversely associated with long-chain PFASs exposure. For example, perfluorotridecanoic acid (PFTrDA; OR = 1.86, 95% CI: 1.51, 2.29) and perfluorodecanoic acid (PFDA; OR = 1.79, 95% CI: 1.36, 2.36) showed the most significant association. In conclusion, this study suggests higher serum PFASs levels were associated with increase odds of VI and vitreous disorder in Chinese adults.

Inequity in Access: Cataract Surgery Throughput of Chinese Ophthalmologists from the China National Eye Care Capacity and Resource Survey

Purpose: To investigate the distribution of cataract surgery performed by ophthalmologists in China.Methods: A cross-sectional study was designed to investigate nationwide ophthalmological resources and capacity for cataract surgery in China⁠-The 2014 China National Eye Care Capacity and Resource Survey. Data analyzed in this report included regional distribution, urban-rural comparison, levels and types of medical institutions, and cataract surgery types and volume per surgeon. In China, only ophthalmologists at or above the level of attending are eligible to perform cataract surgery independently, so the ability of cataract surgery for ophthalmologists at or above the level of attending is analyzed in the current study. Descriptive statistics were used.Results: 36,333 ophthalmologists were included in this survey, which is an average of 1.33 ophthalmologists to every 50,000 population. Of the surgeons in this survey, 23,412 (50.22%) were attending or more senior ophthalmologists and were mainly distributed in eastern urban areas. Annual average cataract surgeries per ophthalmologist in China were 259 in 2017, less than 300 cases.Conclusion: The average number of ophthalmologists per population in China has achieved the goal of WHO's Vision 2020; however, these surgeons are concentrated in urban areas. Further, the ability of cataract surgery among ophthalmologists is unbalanced. The annual average cataract surgeries performed by ophthalmologists are insufficient, which is an important factor resulting in the current situation in China that ophthalmic service capacity has not met the requirements for eliminating cataract blindness.

Patterns and Risk Factor Profiles of Visual Loss in a Multiethnic Asian Population: The Singapore Epidemiology of Eye Diseases Study

PURPOSE

To describe the pattern and risk factor traits associated with visual loss (defined as either visual impairment [VI] or blindness) in a multiethnic Asian cohort of Malay, Indian, and Chinese individuals living in Singapore.

METHODS

A total of 10 020 participants from the Singapore Epidemiology of Eye Diseases Study were examined between 2004 and 2011. All underwent standardized examinations. VI (visual acuity <20/40 to ≥20/200) and blindness (visual acuity <20/200) were defined based on the US definition, better-seeing eye. Singapore Population Census 2010 was used to calculate age-standardized prevalence. Multiple logistic regression analysis was performed to determine the independent and joint risk factors associated with visual loss.

RESULTS

Malay individuals had higher age-standardized prevalence of best-corrected and presenting VI (5.4% and 19.9%, respectively) than Indian (3.6% and 18.0%) and Chinese individuals (3.3% and 17.2%). Cataract was the main cause for presenting and best-corrected blindness; cataract and diabetic retinopathy were the top causes for best-corrected VI, consistently observed across the 3 ethnic groups. Older age, female sex, lower socioeconomic status, diabetes, systemic comorbidities, and cognitive impairment were independently associated with increased risk of best-corrected visual loss (all P ≤ .027). Individuals aged ≥60 years with diabetes were 12.7 times (95% confidence interval, 8.39-19.23) likely to have best-corrected visual loss, compared with younger, nondiabetic individuals. Lower income and education explained 58.1% and 23.2% of best-corrected visual loss in this population, respectively.

CONCLUSION

In this urban multiethnic Asian population, we identified common traits associated with visual loss across Malay, Indian, and Chinese individuals. These results will be useful for the planning and designing of eye health services and strategies for Asia's rapidly developing populations living in urban communities. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Prevalence of and Risk Factors for Diabetic Retinopathy in a Rural Chinese Population: The Yangxi Eye Study

Purpose

To investigate the prevalence and determinants of diabetic retinopathy (DR) among older adults in rural Southern China.

Methods

Using random cluster sampling, persons aged 50 years or older were randomly selected in rural Yangxi County, Guangdong Province, China. All participants underwent a standardized interview, fundus photography, and point of service glycosylated hemoglobin A1c (HbA1c) testing. Diabetes mellitus (DM) was diagnosed based on confirmed medical history or HbA1c ≥6.5%. Fundus photographs were graded for DR and diabetic macular edema (DME) based on the United Kingdom National Diabetic Eye Screening Program guidelines. Prevalence of and risk factors for DR and vision-threatening diabetic retinopathy (VTDR) were evaluated.

Results

Among 5825 subjects who participated (90.7% response rate) in the Yangxi Eye Study, 562 (9.6%) were diagnosed with DM, including 79 (14.1%) known and 483 new (85.9%) cases. Among DM cases, 476 (84.7%) had gradable fundus photos. The prevalence of any DR and VTDR were 8.19% (95% confidence interval [CI] 5.9-11.0) and 5.25% (95% CI 3.43-7.66), respectively. These figures were 23.9% and 12.7% for known and 5.43% and 3.95% for new DM cases. Risk factors for any DR were higher HbA1c level (OR [odds ratio] per unit 1.34, P < 0.001), longer duration of DM (OR per year = 2.29, P < 0.001) and having previously undergone cataract surgery (OR 4.11, P < 0.030).

Conclusions

Our study found a lower prevalence of DR among adults 50 years and older than in previously reports. Perhaps this difference can be explained by the short duration of most cases.

The association between socioeconomic status and visual disability among older adults in China

AIM

To investigate the association between socioeconomic status (SES) and visual disability (VD) among older Chinese adults.

METHODS

We obtained data from the Second National Sample Survey on Disability, conducted in China in 2006. A total number of 192 375 older adults (aged≥65y) were screened for suspected VD via interviews with trained examiners. Those who screened positively for VD were referred to ophthalmologists to obtain a final diagnosis.

RESULTS

VD was prevalent among 7.29% of Chinese adults aged 65 and older, and was higher in rural areas (8.71%) than in urban areas (4.82%). After adjusting for SES indicators and covariates, we found that less-educated older adults were more likely to suffer from VD, with an odds ratio (OR) of 2.50 (95%CI: 2.26-2.82) for illiterates, compared with those who graduated from senior high school or above. Older adults who were in the lowest income quintile were more at risk of VD, with an OR of 1.81 (95%CI: 1.68-2.95), compared with adults in the highest income quintile. In urban areas, when compared with adults who graduated from senior high school or above, those who did not continue their education after junior high school, primary school, or those who were illiterate, were more likely to suffer from VD, with an OR of 1.35 (95%CI: 1.51-1.59), 1.84 (95%CI: 1.60-2.12), and 2.63 (95%CI: 2.27-3.04), respectively. Lower levels of income were statistically significant when associated with VD. In rural areas, adults who were illiterate had an OR of 2.21 (95%CI: 1.75-2.79) when compared to adults with senior high school or above education level. Per capita, household income remained significantly associated with VD. Older adults who were ≥85, female, single, and residing in rural areas were associated with higher risks of VD.

CONCLUSION

Individual-level SES among the elderly, in the form of education and income, is associated with VD among elderly Chinese adults in both urban and rural areas; however, the association is stronger in rural areas. Further studies are still required to explore the mechanism behind the relationships.

Causes of Visual Impairment and Blindness in the 2006 and 2014 Nine-Province Surveys in Rural China

PURPOSE

To investigate the primary causes of visual impairment and blindness in rural China.

DESIGN

Population-based, cross-sectional study.

METHODS

Geographic cluster sampling was used in randomly selecting residents from a rural county/district within 9 provinces in the East Coast, Inland Middle, and West regions of mainland China. Persons aged 50 years or older were enumerated through household visits and invited to examination sites for visual acuity testing and ocular examination. Causes of vision impairment and blindness in 2014 were compared with data from an earlier 2006 survey.

RESULTS

Mild visual impairment (20.4% prevalence) was caused by uncorrected refractive error in two thirds of cases and by cataract in nearly another one fourth; moderate-to-severe visual impairment (10.3% prevalence) was caused by cataract in over onec half of cases and by uncorrected refractive error in another one fifth; blindness (1.66% prevalence) was caused by cataract in approximately one half of cases and in another one fourth by retinal disease. Primary causes of visual impairment and blindness in cataract-operated eyes were uncorrected refractive error, posterior capsule opacity, and retinal disease. From 2006 to 2014, the proportion of visual impairment caused by uncorrected refractive error increased, but rates for unoperated cataract were reduced.

CONCLUSIONS

Uncorrected refractive error and unoperated cataract are the 2 primary causes of mild, moderate, and severe visual impairment in rural China, with unoperated cataract and retinal diseases primary causes for blindness. An effective public health strategy to increase service delivery for these causes would lead to substantial reduction in vision impairment and blindness.

Cataract Surgical Coverage and Visual Acuity Outcomes in Rural China in 2014 and Comparisons With the 2006 China Nine-Province Survey

PURPOSE

To estimate surgical coverage of cataract-related vision impairment and blindness and visual acuity outcomes in operated eyes in rural China in 2014 with comparisons with the 2006 Nine-Province Survey.

DESIGN

Population-based, cross-sectional study.

METHODS

Geographical cluster sampling was used in randomly selecting residents from a rural county or semi-rural district within 9 provinces: Beijing, Jiangsu, Guangdong, Heilongjiang, Jiangxi, Hebei, Ningxia, Chongqing, and Yunnan. Persons 50 years of age or older were enumerated through household visits and invited to examination sites for visual acuity testing and ocular examination. Surgical coverage and visual acuity outcomes in 2014 were compared with data from the 2006 survey.

RESULTS

Among 51 310 examined persons, surgical coverage among those presenting with cataract-related severe visual impairment or blindness (<20/200) was 62.7% overall, ranging from 43.4% to 83.6% across the 9 study sites. Unoperated cataract was significantly associated with older age, female sex, and lack of education. Presenting visual acuity outcomes ≥ 20/63 in cataract-operated eyes was 62.2% overall, ranging from 51.6% to 78.6%, and 75.2%, ranging from 67.1% to 81.5%, with best-corrected visual acuity. As a proportional percentage of cataract surgical coverage in 2006, overall surgical coverage increased by 81.4% during the 2006-2014 interval, and by 110% when adjusted for visual acuity outcomes ≥ 20/63.

CONCLUSIONS

Cataract blindness control is well underway in rural China, as evidenced by significant increases in cataract surgical coverage and improvement in visual acuity outcomes during the 2006-2014 interval. Further efforts are needed to provide greater access to affordable cataract surgery for the elderly, female persons, and those with little or no education.

General analysis of factors influencing cataract surgery practice in Shanghai residents

Background

It was reported that lack of knowledge, less confidence of medical services, commute difficulties, and poor economic conditions would be the main barriers for cataract surgery practice. The influencing factors could have changed in cities with high developing speed. Shanghai is one of the biggest cities in China and the world. The purpose of the study was to explore the factors influencing cataract surgery practice in Shanghai.

Methods

This was a population-based, cross-sectional study. A total of 2342 cataract patients older than 50 years old with cataract-induced visual impairment or who had undergone cataract surgery were recruited from rural and urban areas of Shanghai. Participants accepted a face-to-face structured questionnaire. Data were collected on patient demographics, education, work, income, health insurance, awareness about cataracts disease, treatment and related medical resources and deration policy, transportation and degree of satisfaction with hospitals.

Results

There were 417 patients who had received cataract surgery, 404 of them supplied complete information in the questionnaire. More female subjects (64.6%) than male subjects (35.4%) accepted cataract surgery among the 404 patients. Of the patients with cataract history, 36.4% of surgery patients were equal or older than 80. More people with urban medical insurance received surgery (p = 0.036). Patients who received surgery were more satisfied with local medical service (p = 0.032). In urban area, Lower income and difficulties with commutes were related to a higher rate of surgery.

Conclusions

Cataract patients with the following features were more inclined to receive surgery: female, old age, better awareness. In urban areas low income and difficult commutes did not represent barriers for cataract surgery, probably because of appropriate cataract surgery promotion policies recent years in Shanghai. In rural areas, better healthcare reimbursement policies would likely lead to a higher uptake of cataract surgery. Further cohort studies with more controls could supply stronger evidence for our viewpoint.