Visual Impairment and Suicide Risk: A Systematic Review and Meta-Analysis

Key Points

Question  Is visual impairment associated with suicide risk, and if so, what factors contribute to the association?

Findings  In this systematic review and meta-analysis including 31 studies and 5 692 769 unique individuals, visual impairment was associated with an increased risk of suicide, including suicidal ideation, suicidal behavior, and suicide death. This elevated risk was particularly pronounced among adolescents with visual impairment.

Meaning  These findings suggest an association between visual impairment and an elevated risk of suicidal tendencies, with variations in risk observed across age groups and a particularly pronounced risk among adolescents.

Importance  Suicide is a substantial public health concern that involves various recognized contributing factors. Sensory impairments, specifically visual impairment, are deemed potential risk factors. Nonetheless, comprehensive information about associated risk levels and underlying determinants remains limited.

Objective  To investigate the association between visual impairment and different aspects of suicide, including the assessment of risk levels and exploration of potential contributing factors.

Data Sources  An electronic search was performed in the PubMed, EMBASE, Scopus, and Cochrane Library databases from their inception to February 8, 2024.

Study Selection  All published studies were considered without restrictions on study design, publication date, or language.

Data Extraction and Synthesis  Two independent reviewers extracted the published data using a standardized procedure in accordance with the Meta-analysis of Observational Studies in Epidemiology (MOOSE) and Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Random-effects meta-analyses were used to estimate pooled effect sizes. Multiple meta-regression analyses were conducted to identify potential factors contributing to the association between visual impairment and the risk of suicide.

Main Outcomes and Measures  The primary outcome measure was the odds ratio (OR) of suicidal behavior (including suicide attempt and suicide death) for individuals with visual impairment compared with those without. The secondary outcome measures were the pooled ORs of suicidal ideation and suicide death, respectively.

Results  A total of 31 population-based studies with 5 692 769 unique individuals (mean [SD] age, 48.4 [8.5] years; 2 965 933 females [52%]) were included. For 17 studies (5 602 285 individuals) that evaluated suicidal behavior, the pooled OR was 2.49 (95% CI, 1.71-3.63). For 21 studies (611 899 individuals) that assessed suicidal ideation, the pooled OR was 2.01 (95% CI, 1.62-2.50). For 8 studies (5 067 113 individuals) investigating the association between visual impairment and suicide death, the pooled OR was 1.89 (95% CI, 1.32-2.71). The multiple meta-regression model identified age group as a predictive factor associated with suicidal behavior, with the studies included suggesting that adolescents were at the highest risk. While this analysis showed moderate heterogeneity for suicide death, high heterogeneity was observed for suicidal behavior and suicidal ideation.

Conclusions and Relevance  The findings of this systematic review and meta-analysis support the association between visual impairment and increased risk of suicidal tendencies. The risk differed by age group, with a pronounced risk observed among adolescents.

Suicide, which has an estimated annual death toll of nearly 1 million lives worldwide,¹ is a significant and urgent global public health challenge. Although a growing body of literature has addressed the topic of suicide, its comprehension and synthesis can be complex due to the various phenotypes that fall within the spectrum of suicide. These phenotypes encompass suicidal ideation, which is characterized by thoughts of ending one’s own life in an active form (with a specific plan) or in a passive form (with a mere desire to die but lacking a concrete plan), suicide attempt, and death by suicide.²

Risk factors for suicidal ideation differ from those for the transition to suicidal behavior, which includes suicide attempt or completed suicide.³ Family history of suicide or suicide attempt, mental disorders, chronic physical illness, and sociodemographic factors contribute to increased risk of suicide.^4,5 Among older populations, additional risk factors include sleep disorders, reduced mobility, compromised quality of life, and significant functional impairment.^6,7

More than 500 million individuals are blind or have significant visual impairment worldwide.⁸ Visual impairment is linked to challenges such as decreased independence, social skills, and personal income.⁹ It also raises the risk of mental health issues such as depression, stress, and a decline in overall quality of life.¹⁰ Accordingly, previous studies have suggested a plausible association between visual impairment and increased risk of suicide.^4,11,12 Nonetheless, the consistency and magnitude of this association exhibit variability among studies, posing a challenge for assessments of the precise nature of the association and the extent of the associated risk. The objective of this systematic review and meta-analysis was to consolidate the available literature on the association between visual impairment and diverse aspects of suicide, with the intention of illuminating both the extent of this association and the potential risk factors.

This study was exempt from institutional review board approval and the need for informed consent, as it exclusively used previously published data and did not qualify as human participant research according to the Seoul National University Hospital Institutional Review Board guidelines. The study followed the Meta-Analysis of Observational Studies in Epidemiology (MOOSE) and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines. The study protocol was prospectively registered with PROSPERO (CRD42022325106) and has been published.¹³

With the assistance of an academic librarian, we conducted a systematic literature search of key databases, including PubMed, EMBASE, Scopus, and the Cochrane Library, to identify relevant studies from their inception to February 8, 2024. Our search strategy used a combination of medical subject headings and text words related to visual impairment and suicide. The search terms encompassed concepts such as visual impairment, low vision, blindness, suicide, suicidal ideation, suicide attempt, suicidal behavior, and association. No restrictions were imposed in terms of the study design, publication date, or language. Additionally, we manually searched the reference lists of published articles to identify any relevant studies missed in the electronic searches. The complete search strategy is outlined in eAppendix 1 in Supplement 1.

Two independent reviewers (C.Y.K. and A.H.) rigorously screened the titles and abstracts of the identified studies in accordance with predefined inclusion criteria. Subsequently, the full-text articles of the potentially eligible studies underwent meticulous evaluation for inclusion by the reviewers. Any discrepancies or disagreements during the screening process were resolved through consultation with a third investigator (Y.K.K.). In cases where multiple publications reported findings from the same study population, we included only the most comprehensive report with the largest sample size after verifying for duplicates.

We included studies that met the following criteria: (1) population-based; (2) reporting visual impairment as a covariate; (3) incorporating suicide death, suicidal ideation, or suicide attempts as outcome measures; and (4) providing odds ratios (ORs) or relative risks (RRs) with corresponding 95% CIs as measures of association or allowing for computation of these measures based on count data reported in the article. We excluded studies that (1) focused solely on pediatric populations; (2) constituted narrative and/or systematic reviews, case reports, commentaries, editorials, or conference abstracts; and (3) lacked a clear definition of visual impairment or a detailed description of the assessment of suicide.

For each included study, data extraction was performed independently by 2 reviewers (C.Y.K. and A.H.) using a standardized data collection form available in Microsoft Access 2016 (Microsoft Corp). Conflicting data entries were identified by algorithm. The extracted information was as follows: (1) study identification details, such as name of first author and publication year; (2) baseline study year; (3) country of study; (4) total number of participants; (5) race and ethnicity of participants, since disparities in suicide rates among populations based on race and ethnicity are well known; (6) age and sex distribution of participants; (7) details on visual impairment assessment; (8) aspects of suicide measured; (9) measures of association (ORs or RRs) with accompanying 95% CIs; and (10) adjustment for confounding factors, if applicable.

Regarding visual impairment, we extracted information pertaining to (1) the operational definition of visual impairment used in the study and (2) the specific method used for visual impairment assessment. For suicide-related outcomes, we extracted (1) the precise definitions of suicidal ideation and suicide attempts as stipulated within the study and (2) the method used to confirm instances of suicide death. In instances where specific details were not readily available within the published article, attempts were made to contact the corresponding author and solicit supplementary information.

The primary outcome measure was the pooled OR of suicidal behavior among individuals with visual impairment compared with those without, and the secondary outcome measures were the pooled ORs of suicidal ideation and suicide death. We conducted a meta-analysis for exposure (visual impairment) and each outcome combination (suicidal behavior, suicidal ideation, and suicide death) using inverse variance–weighted random-effects models to combine the study-specific measures of association. We included both unadjusted and adjusted estimates of increased risk, giving priority to adjusted estimates for our analysis. When count data were available, we calculated unadjusted measures of association. In cases where neither count data nor risk estimates were provided, we calculated the standardized mortality ratio based on the reference-population statistics provided in the respective studies.¹⁴ The quantification of between-study outcome variation (ie, heterogeneity) was conducted using the I² statistic. This metric illustrates the percentage of variation across studies attributed to heterogeneity rather than to chance, irrespective of the treatment effect metric used.¹⁵ Drapery plots were created to illustrate, as curves, the P value function for each individual study and pooled estimates in each meta-analysis, along with the prediction range for a single future study.¹⁶

Due to the discrepancies in definitions of the degree of visual impairment (which included both low vision and blindness)¹⁷ across studies, it was impractical to combine multiple study findings by visual impairment severity. Consequently, we consolidated multiple ORs provided by a study based on visual impairment severity categories to derive a single OR value per study. In cases where individual studies presented different ratio measures of association (eg, OR and/or RR), we considered these estimates to be reasonably similar given the rarity of suicide occurrences.¹⁸

We also conducted meta-regression analyses to investigate possible causes of heterogeneity across studies.¹⁹ These analyses aimed to explore differences in study characteristics and populations that potentially could have altered the association with visual impairment on the risk of suicide. The 8 covariates included were as follows: (1) publication year, (2) main ethnicity of study participants, (3) mean (SD) age of study participants, (4) total sample size, (5) vision assessment method, (6) consideration of potential confounding factors, (7) continents where study was conducted, and (8) studies conducted in low-income country. Definitions of each of the covariates are provided in eTable 1 in Supplement 1.

In multiple meta-regression analysis, one can try to model all possible combinations of predictive factors associated with outcomes (ie, covariates) in a procedure termed multimodel inference. This allows for determination of which possible covariate combination provides the best fit and which are the most important overall.²⁰ We modeled all possible combinations of 8 covariates (2⁸ = 256) and determined the model that performed best with a lowest value of Akaike information criterion corrected.

Additionally, graphic display of heterogeneity (GOSH) plot analysis,²¹ a sophisticated means of exploring the patterns of effect sizes and heterogeneity in our data, was performed. This method uses 3 clustering algorithms: K-means clustering,²² density-based spatial clustering of applications with noise,²³ and Gaussian mixture models.²⁴ For those plots, we fit the same meta-analysis model to all possible subsets of our included studies. Then, sensitivity analysis was applied to test the effect of rerunning the meta-analysis after removing studies potentially contributing to cluster imbalance. All statistical analyses were conducted using R, version 4.0.4 (R Project for Statistical Computing). Two-sided P < .05 was considered statistically significant.

To assess the methodological quality of the included studies, we used the Newcastle-Ottawa Scale, a validated tool for evaluating the quality of cross-sectional, case-control, and cohort studies (eAppendix 2 in Supplement 1).²⁵ Our qualitative assessment for publication bias involved the use of funnel plots.²⁶

A total of 3239 studies were initially identified through a systematic search. Following a process of duplicate exclusion and abstract screening, 101 studies were considered potentially relevant and subjected to a thorough full-text review. Ultimately, 31 studies were included,^27-57 encompassing a combined study population of 5 692 769 individuals (mean [SD] age, 48.4 [8.5] years; 2 965 933 female [52%] and 2 726 836 male [48%]). The stepwise selection process is depicted in Figure 1.

The publication timeline of the studies varied, with 2 studies published in the 1990s,^27,28 5 in the 2000s,^29-33 12 in the 2010s,^34,36-46 and 12 in the 2020s.^35,47-57 Geographically, the studies covered a diverse range of regions, with 8 studies conducted in Europe,^{28-30,33,38,44,45,50} 10 in Australia and Asia,^{27,31,39-43,46,56,57} 11 in North America,^{32,34,36,37,47,48,51-55} 1 in the Middle East,³⁵ and 1 involving multiple countries.⁴⁹ The detailed characteristics of each included study can be found in Table 1. The definitions and criteria of the methods used to assess visual impairment and risk of suicide are provided in Table 2.

The association between visual impairment and suicidal behavior was investigated in 17 studies^{29,30,32,34-37,40,44,46,48,50,53-57} with a total of 5 602 285 participants. Our summary estimate of visual impairment as a risk factor for suicidal behavior was an OR of 2.49 (95% CI, 1.71-3.63), with heterogeneity of I² = 92.8% (P < .001) (Figure 2A). A total of 21 studies^{27,28,31,33,35,38-43,45,47-55} assessed suicidal ideation, encompassing 611 899 participants. The pooled OR for the association between visual impairment and suicidal ideation was 2.01 (95% CI, 1.62-2.50), with heterogeneity of I² = 89.0% (P < .001) (Figure 2B). Eight studies^{29,30,32,37,44,46,56,57} involving a total of 5 067 113 participants examined the association between visual impairment and the risk of suicide death. The pooled OR was 1.89 (95% CI, 1.32-2.71), with heterogeneity of I² = 73.6% (P = .002) (Figure 2C). Drapery plots in eFigures 1 and 2 in Supplement 1 show the different meta-analytic results by P value functions.

Meta-regression analyses were undertaken to establish the association between individual moderators (predictive factors) and the pooled effect size (ie, risk of suicidal behavior). Within the group of 8 moderators, the mean age of study participants was a notable risk factor for suicidal behavior. Specifically, 71.3% of the variance in true effect sizes could be attributed to age. The Test of Moderators also showed significance (P < .001) (eTable 2 in Supplement 1). This signifies that the predictive factor—namely, the mean age of study participants—indeed was associated with the effect sizes of the studies.

Random-effects meta-regression analyses showed that participant age was a possible risk factor. Thus, we performed a subgroup analysis comparing effect sizes according to mean age (eTable 3 in Supplement 1). The pooled OR for studies that had included adolescent patients was 9.85 (95% CI, 4.39-22.10), representing the highest value among the various age groups. The second-highest OR was observed among individuals older than 65 years at 6.66 (95% CI, 2.95-15.00).

Multiple meta-regression analyses were performed to identify the blend of multiple moderators predictive of the pooled effect size, while also considering interactions among moderators. The most optimal model for estimating risk of suicidal behavior in patients with visual impairment was the blend of moderators (Akaike information criterion corrected, 29.7), encompassing mean age of study participants (model importance, 0.99), consideration of potential confounding factors in a study (model importance, 0.27), and country where the study was conducted (model importance, 0.21). A model-averaged plot of predictive factor importance displays the significance of each factor across all of the models (eFigure 3 in Supplement 1). The results for predictive factors associated with suicidal ideation risk in patients with visual impairment are plotted in eFigure 4 in Supplement 1.

Our results showed 2 peaks suggestive of the effect size heterogeneity patterns for the association between visual impairment and risk of suicidal behavior (eFigure 5 in Supplement 1). The 3 clustering algorithms for detection of different clusters in a GOSH plot were applied and detected 2 studies^34,35 that might have contributed to cluster imbalance. After excluding these 2 potential outliers, we again performed the meta-analysis and obtained 1.83 (95% CI, 1.48-2.28) as the pooled OR for visual impairment and risk of suicidal behavior (eTable 4 in Supplement 1).

Figure 3 shows a funnel plot illustrating the potential publication bias. The studies are distributed around the pooled effect size (indicated by the vertical line at the center), both within and outside the funnel’s contours. This suggests a reduced likelihood of significant bias in smaller studies, which are more susceptible to yielding nonsignificant results and thus potentially going unnoticed. Funnel plots for suicidal ideation and suicide death are shown in eFigure 6 in Supplement 1.

Our comprehensive meta-analysis of 31 population-based studies revealed an association between visual impairment and elevated risk of suicide encompassing suicidal behavior, suicidal ideation, and suicide death. Notably, through multiple meta-regression analyses, we uncovered a particularly pronounced risk of suicide associated with visual impairment among adolescents.

For individuals with visual impairment, the underlying causes of suicidal behavior may be complex and multifactorial. A nationwide survey conducted in the US found that approximately 88% of respondents regarded eye health as a critical component of their overall well-being, with blindness being ranked as the most severe conceivable health outcome.⁶⁰ Indeed, visual impairment has implications that extend beyond the confines of clinical ophthalmology. Systematic examination of and consultation with patients with visual impairment consistently reveal a concerning level of compromised quality of life, reduced physical activity, social isolation, decline in autonomy, diminished personal income, and substantial prevalence of depression.^9,61,62 Notably, these factors are widely recognized as significant risk factors for suicide.⁶³

In the literature, 2 meta-analyses have investigated the potential association between visual impairment and suicide. Rajeshkannan et al⁶⁴ identified a correlation between suicidal ideation (OR, 1.53 [95% CI, 1.30-1.79]) or suicide attempt (OR, 4.55 [95% CI, 2.39-8.67]) and visual impairment based on 6 relevant studies. Palbo et al,⁶⁵ having integrated 8 studies into a quantitative analysis, also posited elevated risks of suicide death (OR, 7.00 [95% CI, 2.30-21.40]), suicide attempt (OR, 2.62 [95% CI, 1.29-5.31]), and suicidal ideation (OR, 1.83 [95% CI, 1.40-2.40]) among individuals with visual impairment. However, the restricted number of studies integrated into their analysis impeded Palbo et al⁶⁵ from achieving precise measurements of risk magnitude and constrained their potential to conduct additional analyses. Our report encompasses 31 studies identified through meticulous literature searches, thus allowing for comprehensive summary estimates regarding the association between visual impairment and risk of suicide and facilitating the execution of meta-regression analyses.

In our results, studies focusing on adolescents with visual impairment demonstrated the highest risk of suicidal behavior. Adolescence is a complex stage of life in which both physiological and psychological changes begin. In this period, individuals cultivate independence and build social networks by acquiring new skills and knowledge and navigating educational and interpersonal ups and downs.⁶⁶ In the studies scrutinized, symptoms related to anxiety, tension, and general distress were significantly higher in adolescents with visual impairment than in those without.⁶⁷ Through interviews with adolescents with visual impairment, Rainey et al⁶⁸ demonstrated that these individuals had significant concerns about their future lives. They voiced worries about facing potential prejudice from future employers, managing independent living in unfamiliar surroundings, and shouldering the sole responsibility for household matters, including finances.

This study has some limitations. First, heterogeneities between the examined studies warrant attention. The study population differed to a certain degree; for example, some studies focused on elderly individuals, 1 included homeless individuals, 2 focused on patients with vision-related diagnoses, and others had a broader demographic focus. Although we performed a rigorous sensitivity analysis to validate the results, a potential association between study heterogeneities and the pooled effect remains. Second, methods used to assess the outcome varied among the studies. Parameters related to suicide were evaluated using questions in different phraseology, language, and time frames of interest. Third, variations in the definition, classification, and assessment methods for visual impairment in each study could potentially confound the association between visual impairment and suicide risk. Specifically, objective assessment of vision might better reflect associated ocular diseases and/or physiological decline. Conversely, self-reported vision may be a marker of functional performance in activities of daily living and may be exacerbated by psychological distress such as depression and social isolation. Our model-averaged plots of predictive factor importance, which illustrate the significance of each factor across all models, revealed that the vision assessment methods did not emerge as a significant factor. This suggests that the association between visual impairment and suicide risk might be independent of the types of vision assessment methods used in the studies. However, we believe that it is crucial to acknowledge the discrepancies in definitions and assessments of the degree of visual impairment across studies as significant factors in interpreting the results. Fourth, although most of the studies included in the analysis adjusted for depression and other important risk factors, the potential confounding of additional risk factors cannot be ruled out. Since the etiology of suicidal behavior is complex, and because diverse risk factors are associated with different individual and cultural contexts, further research is warranted to determine which factors may modulate the risk of suicide in patients with visual impairment.

In this systematic review and meta-analysis of visual impairment and suicide risk, an association between visual impairment and an increased risk of suicide was identified. This finding emphasizes the importance of eye health to overall mental well-being. It is recommended that clinicians remain attentive to the elevated risk and be ready to implement suitable suicide prevention measures when required, especially when dealing with adolescents. In addition, the limited number of studies addressing adolescents with visual impairment and suicide highlights the importance of conducting additional research in this area.

Accepted for Publication: February 19, 2024.

Published: April 17, 2024. doi:10.1001/jamanetworkopen.2024.7026

Correction: This article was corrected on May 21, 2024, to include the correct author affiliation for Dr Shim.

Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2024 Kim CY et al. JAMA Network Open.

Corresponding Authors: Young Kook Kim, MD, PhD, Department of Ophthalmology, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul 03080, Korea (eyedry@snu.ac.kr); In Boem Chang, MD, PhD, Seoul ON Eye Clinic, 750 Tongil-ro, Eunpyeong-gu, Seoul 03355, Korea (ibeyebe0515@gmail.com).

Author Contributions: Prof Y. K. Kim had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Dr C. Y. Kim and Prof Ha contributed equally to the study as co–first authors.

Concept and design: Ha, Chang, Y. K. Kim.

Acquisition, analysis, or interpretation of data: C. Y, Kim, Ha, Shim, Hong, Y. K. Kim.

Drafting of the manuscript: C. Y. Kim, Ha, Y. K. Kim.

Critical review of the manuscript for important intellectual content: C. Y. Kim, Shim, Hong, Chang, Y. K. Kim.

Statistical analysis: C. Y. Kim, Shim, Y. K. Kim.

Obtained funding: Y. K. Kim.

Administrative, technical, or material support: C. Y. Kim, Ha, Y. K. Kim.

Supervision: Ha, Hong, Y. K. Kim.

Conflict of Interest Disclosures: None reported.

Funding/Support: This study was supported by grant NRF-2021R1F1A1062503 from the National Research Foundation of Korea.

Role of the Funder/Sponsor: The funder had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication. The study and researchers are independent of the funder.

Meeting Presentation: This study was presented as a poster to the 2022 American Academy of Ophthalmology Annual Meeting; October 1, 2022; Chicago, Illinois.

Data Sharing Statement: See Supplement 2.