With the escalating global aging population, near vision loss (NVL) has emerged as a significant health issue impacting the quality of life among middle-aged and elderly individuals. NVL is typically caused by uncorrected presbyopia, a condition where the elasticity of the eye’s lens gradually diminishes with age, thereby impairing the eye’s ability to focus on near objects
[1-2]. The latest Global Burden of Disease (GBD) 2021 database provides updated estimates of the global prevalence of NVL, highlighting the increasing burden of this condition and indicating that uncorrected presbyopia affects a large portion of the global population
[2-3]. It is projected that by 2050, 1.8 billion people globally will be affected by presbyopia, with approximately 826 million individuals facing NVL
[4].
In recent years, changes in lifestyle and the widespread use of electronic devices have led an increasing number of young people to face the issue of NVL. Although NVL is particularly prevalent among those over 40, its impact on quality of life is often underestimated. Studies
[5-7] have shown that NVL not only reduces efficiency in learning and work but also heightens the risk of accidents, and may lead to mental health issues such as depression and anxiety, further exacerbating both individual and societal burdens. As the global population continues to age, the burden of NVL is expected to intensify. Therefore, in-depth research on the epidemiological trends and impacts of NVL is crucial for the development of effective public health strategies.
Globally, the epidemiological characteristics of NVL exhibit notable regional and demographic variations
[8]. Particularly in developing countries, and especially in China, the burden of NVL is increasing rapidly. Urbanization, educational pressures, and the widespread use of electronic devices are the primary factors driving this trend
[9-11]. Recent studies
[12-13] have highlighted the growing global and Chinese NVL burden, but a comprehensive analysis focusing on long-term trends, gender, and age differences remains needed. This study addresses this gap by analyzing NVL trends from 1990 to 2021 and projecting future burdens using the latest GBD 2021 database, aiming to inform targeted public health interventions.
1 Materials and methods
1.1 Ethics statements
All data used in this study were sourced from publicly accessible databases and adhered to relevant ethical standards and data usage permissions. The study did not involve any personally identifiable information, and thus, no additional ethical approval was required. The research follows the guidelines for accurate and transparent health estimation reporting (GATHER)
[14].
1.2 Data source
We acquired data from the Global Health Data Exchange (GHDx) query tool on GBD 2021, a study released in 2024, covering epidemiological data from 204 countries and 811 regions, including 288 causes of death, 371 diseases and injuries, as well as comparisons of 88 risk factors
[15-16]. The GBD database integrates data from vital registration systems, censuses, health surveys, and epidemiological studies, employing sophisticated statistical models for adjustment and calibration to ensure the reliability and comparability of the data. Utilizing the GHDx online platform, we conducted searches and downloaded NVL-related data for different gender and age groups in China from 1990 to 2021. This study focused on analyzing the following variables: Prevalence, disability-adjusted life years (DALYs), age-standardized prevalence rate (ASPR), age-standardized DALYs rate (ASDR), and case numbers. Specifically, the term “rate” refers to the comparative metrics used to assess the relative burden of disease across different populations or demographic groups, which allow us to compare the burden of NVL across different demographic groups
[17].
DALYs encompass years of life lost due to premature death and years of healthy life lost due to disability
[18]. This metric is employed to provide a comprehensive assessment of the impact of disease on healthy life expectancy.
Although the GBD database provides incidence data, this study did not include it in the analysis for the following reasons: 1) As a chronic disease, NVL’s prevalence more consistently reflects the long-term burden, whereas incidence is more susceptible to the effects of screening or intervention measures. 2) DALYs already integrate both prevalence and disability weights, offering a more comprehensive representation of the disease’s impact on healthy life expectancy.
1.3 Classification of diseases
According to the International Classification of Diseases and Related Health Problems, 10th Revision (ICD-10), NVL is typically associated with presbyopia. Presbyopia is a common age-related condition characterized by the gradual loss of the eye’s ability to focus on nearby objects. The ICD-10 coding for NVL related to presbyopia was detailed in other studies, typically under the code H52.4, which specifically categorizes presbyopia
[19].
1.4 ARIMA prediction model
The autoregressive integrated moving average (ARIMA) is a widely used tool for time series analysis and forecasting. It combines 3 components: autoregressive (AR), integration (I), and moving average (MA), typically expressed as ARIMA(
p,d,q), where
p represents the order of the autoregressive term,
d is the degree of differencing, and
q is the order of the moving average term. First, we conducted a stationarity test on the data; if the data was non-stationary, we applied differencing to achieve stationarity. Next, we used the autocorrelation function (ACF) and partial autocorrelation function (PACF) to determine the parameters
p and
q of the model. Then, using the “forecast” package in R software, we employed the auto.arima function to automatically select the optimal model, taking into account the Akaike Information Criterion (AIC) and the Bayesian Information Criterion (BIC). Finally, we performed a white noise test to confirm that the residuals of the model follow a random process. Through these steps, the ARIMA model effectively leveraged historical data to forecast future trends
[20-21].
1.5 Statistical analysis
This study employed descriptive statistical methods to compare the trends in the disease burden of NVL in China from 1990 to 2021. We analyzed the absolute prevalence cases, DALYs, ASPR, ASDR, and the estimated annual percentage change (EAPC) with the estimated 95% uncertainty intervals (UI). All statistical analyses were performed using R software (version 4.3.2).
The age-standardized rate (ASR) was defined as the cases per 100 000 individuals, weighted according to the GBD 2021 world age-standard population
[22]. The 95%
UI were used to assess the uncertainty arising from the multiple imputation of missing data
[23].
We employed regression analysis to assess the temporal trend of the NVL burden. Specifically, we fitted a regression curve to the natural logarithm of the ASR, using the following formula:
, where
,
x=calendar year, and
ϵ=error. The EAPC was calculated using the following formula:
. If the EAPC is less than 0, the ASR shows a decreasing trend; if the EAPC is greater than 0, the ASR exhibits an increasing trend; otherwise, the ASR is considered stable
[24].
2 Results
2.1 Global prevalence of NVL in 2021
In 2021, NVL remained a major cause of visual impairment worldwide, with China bearing the highest burden in terms of both prevalence and DALYs among all countries and regions assessed in the GBD study. After age standardization, China’s ASPR and ASDR for NVL were positioned in the upper-middle range globally, exceeding those of the vast majority of nations. Notably, China ranked 18th globally in ASDR. Gender differences were evident, with females demonstrating significantly higher ASPR and ASDR values compared to males (
Tables 1,
Figure 1).
2.2 Prevalence and trends of NVL in China from 1990 to 2021
A substantial increase in the burden of NVL was observed in China between 1990 and 2021. Both the number of prevalence cases and DALYs rose approximately 2.4-fold over this period. After age standardization, the ASPR and ASDR also showed considerable growth, with an EAPC indicating a sustained upward trend throughout the observed years (
Table 2,
Figure 1).
2.3 Changes in the burden of NVL by gender in China in 1990 and 2021
In 2021, the number of male individuals affected by NVL in China was 151 386 233.94, reflecting an increase of 239.65% compared to 1990. The ASPR rose from 9 343.52/100 000 in 1990 to 14 686.21/100 000 in 2021, marking a change of 57.18%, with an EAPC of 1.76. In 2021, the male DALYs due to NVL totaled 1 543 613.48, an increase of 238.68% from 455 779.86 in 1990. The ASDR rose from 94.63/100 000 in 1990 to 149.76/100 000 in 2021, a change of 58.26%, with an EAPC of 1.79 (
Figure 2).
In 2021, the number of female individuals affected by NVL in China was 172 991 519.46, reflecting an increase of 238.82% compared to 1990. The ASPR rose from 10 841.31/100 000 in 1990 to 16 551.70/100 000 in 2021, a change of 52.67%, with an EAPC of 1.72. In 2021, the female DALYs due to NVL totaled 1 749 023.16 person-years, an increase of 238.94% from 1990. The ASDR increased from 108.87/100 000 in 1990 to 167.69/100 000 in 2021, reflecting a change of 54.03%, with an EAPC of 1.75. In 2021, the burden of both prevalence and DALYs due to NVL was higher in females than in males (
Figure 2).
2.4 Changes in the burden of NVL by age group in China in 1990 and 2021
A comparison of the results across age groups reveals that the disease burden of NVL in China from 1990 to 2021 followed a trend of initially increasing and then decreasing. The prevalence cases (58 200 380.90) of NVL in China peaked in the 55-59 age group, after which it gradually declined with advancing age. The trend of the DALY mirrored that of the prevalence cases, with the highest (594 650.90) also occurring in the 55-59 age group (
Figure 3).
2.5 Forecast of the disease burden of NVL in China from 2022 to 2036 (ARIMA Model)
Time series were constructed for the ASPR and ASDR of the total population, females, and males for each year, and ARIMA models were developed to predict the trends in NVL prevalence rates and DALYs over the next 15 years (
Table 3). The results indicated that over the next 15 years, the prevalence rates of NVL in China was expected to gradually increase. By 2036, the ASPR were projected to reach 18 299.53/100 000 (95%
UI 15 372.45/100 000 to 21 226.66/100 000) for the overall population, 17 271.38/100 000 (95%
UI 15 600.34/100 000 to 18 950.45/100 000) for males, and 19 314.79/100 000 (95%
UI 16 288.74/100 000 to 22 340.84/100 000) for females, representing increases of 15.80%, 16.24%, and 14.15%, respectively, compared to 2022. Similarly, the ASDR were projected to reach 193.04/100 000 (95%
UI 160.90/100 000 to 225.18/100 000), 180.50/100 000 (95%
UI 153.70/100 000 to 207.30/100 000), and 203.08/100 000 (95%
UI 169.73/100 000 to 236.45/100 000) for the total population, males, and females, respectively, reflecting increases of 17.29%, 17.97%, and 17.02% from 2022 (
Figure 4).
3 Discussion
This study, through an analysis of the prevalence trends of NVL in China from 1990 to 2021, underscores the severity and complexity of this public health issue. It also provides valuable insights for administrators and policymakers in evaluating and potentially revising current ophthalmic care policies. Firstly, by 2021, the global number of individuals affected by NVL exceeded 1.1 billion, with China leading the world in both prevalence cases and DALYs, particularly among women and the middle-aged and elderly populations. This finding not only reflects China’s vast population base, but also highlights the widespread and severe nature of myopia in the country. As urbanization accelerates and modern lifestyles evolve, the incidence of NVL has risen rapidly, presenting a pressing public health challenge that requires urgent attention.
In the GBD 2019 study, the definition of NVL was similar to that of functional presbyopia, referring to age-related vision loss that can be corrected through optical means
[1]. Our research indicated that the number of individuals affected by NVL increased from 96 million in 1990 to 324 million in 2021, nearly tripling, a growth rate significantly surpassing that of other countries such as India. A study by Wang et al
[25] also observed a marked global increase in NVL, particularly in low-income countries, where DALYs rose from 5.3 million in 1990 to 9.8 million in 2017, reflecting an 82.4% increase. These findings are consistent with our results. This phenomenon may be closely linked to China’s large population base, increased life expectancy, rapid economic development, and ongoing urbanization. Moreover, the EAPC of 1.74 underscores the long-term, stable upward trend of NVL in Chinese society. This suggests that, without effective interventions, this issue may worsen in the coming decades. Therefore, it is imperative to develop and implement effective public health strategies to mitigate the negative impact of NVL on society and healthcare systems.
One of the key findings of this study is the substantial increase in NVL prevalence and DALYs rates among females compared to males. While the prevalence cases has increased for both men and women, the ASPR (16 551.70/100 000) and DALYs (1 749 023.16/100 000) are significantly higher in women, indicating a greater contribution to the disease burden. The mechanisms of gender differences involve both physiological and social factors. Study
[26] has shown that the decline in estrogen levels in women is associated with an increased risk of lens opacity. Women, with their longer life expectancy, are more prone to experiencing age-related vision deterioration. This is especially true under the dual influence of aging and hormonal fluctuations, which exacerbate eye health problems
[27]. As women age, the decline in estrogen levels may heighten the risk of vision loss, particularly in terms of susceptibility to cataracts and neurodegenerative disorders
[28-29]. Moreover, in balancing family and work responsibilities, women often neglect eye health management and early intervention, further exacerbating vision issues
[30]. With China’s accelerating population aging, the burden of uncorrected NVL among the elderly is likely to increase, impacting quality of life. While study
[31] has not found significant gender differences in disease burden—a discrepancy possibly due to variations in research methods, sample populations, and data analysis strategies, we maintain that gender differences still exist in the burden of NVL. Therefore, public health interventions should address gender-specific needs, with a particular emphasis on enhancing vision health management and preventive measures among women. Future research should further explore gender differences across various populations to clarify their influence on the onset and progression of NVL, thereby providing a scientific basis for the development of targeted intervention strategies.
The study by Jin et al
[13] found that the disease burden of NVL is primarily concentrated in the population aged 45 to 80, with the 65-69 age group being the most affected. Our research similarly revealed that the prevalence cases and DALYs of NVL peak in the 55-59 age group and then gradually decline with advancing age. This age group was likely experiencing the dual impact of increased visual demands due to professional and personal responsibilities and the onset of age-related visual impairments. Although prevalence and DALYs decreased after the 55-59 age group, the visual burden among the elderly remained significant. This may be partly attributed to recent improvements in eye care and health policies, such as more widespread vision screening and better healthcare accessibility, which may have helped slow the progression of vision deterioration. The high prevalence and DALYs rates in this age group highlight the need for targeted interventions to address the specific visual health needs of middle-aged individuals.
The projected increase in NVL burden over the next 15 years, as forecasted by the ARIMA model, underscores the urgency of developing effective public health strategies. By 2036, the total prevalence is projected to increase by 15.80%, with men and women experiencing increases of 16.24% and 14.15%, respectively. The DALYs rate is expected to rise by 17.29%, 17.97%, and 17.02%, for overall population, men, and women, respectively. Despite progress in eye care and public health policies, this growth will still pose significant challenges to public health. This trend signals the need for policymakers to place greater emphasis on the prevention and treatment of NVL, implementing more effective interventions. First and foremost, raising awareness about eye health and improving the accessibility and quality of ophthalmic services should be prioritized. Additionally, promoting healthy visual habits in educational and workplace environments is essential to slowing the progression of vision deterioration. The government and relevant institutions should strengthen interdepartmental cooperation to promote health interventions across society, thereby alleviating the burden of NVL and enhancing overall public health. Through these comprehensive strategies, we can not only improve individual quality of life but also mitigate the long-term impact of NVL on public health and socio-economic well-being.
Although this study provides valuable insights into the epidemiological burden of NVL in China, several limitations remain. Firstly, the ARIMA model assumed that future trends will follow historical patterns, which may not account for sudden changes in risk factors (e.g., policy interventions, technological advancements). Secondly, the study primarily relied on existing statistical data and lacked an in-depth analysis of individual-level factors, such as genetic background, lifestyle, and environmental exposures, which may play a significant role in the onset and progression of NVL. Future studies could integrate machine learning approaches to capture non-linear relationships and external volatility factors. By addressing these limitations, future studies would provide a more solid scientific foundation for the prevention, diagnosis, and treatment of NVL, while also offering more precise decision-making support for policymakers.
In this study, we analyzed and forecasted the trends in the disease burden of NVL in China, revealing its changes over the past decades and the next 15 years. The results showed that in 2021, China had the highest number of NVL cases and DALYs globally, with a significant increase since 1990. It is projected that by 2036, the prevalence cases and DALYs rate of NVL will continue to rise, with the burden on women surpassing that of men. This trend underscores the urgency of addressing NVL as a major public health issue. With the intensifying aging process and shifts in demographic structure, the burden of NVL will become even more pronounced, particularly peaking in the 55-59 age group. To confront this challenge, the formulation of effective public health strategies is crucial. This includes raising awareness about eye health, improving the accessibility and quality of ophthalmic services, and promoting healthy eye care habits.
the Natural Science Foundation of Hunan Province(2023JJ30817)
Hunan Provincial Natural Science Foundation-Hengyang City Joint Fund Project(2025JJ70129)
Changsha Natural Science Foundation(kq2403057)
,
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