Linkage between a plant-based diet and age-related eye diseases: a systematic review and meta-analysis

CONTEXT

An increased risk of age-related eye disease has been observed in individuals lacking a balanced diet. Following a plant-based diet may result in nutritional insufficiencies and negatively affect health if an effort is not made to ensure the consumption of fortified foods or specific supplements.

OBJECTIVE

The purpose of this article is to characterize the relationship between plant-based diets and age-related ocular outcomes among adults.

DATA SOURCES

A comprehensive literature review was performed using the MEDLINE, Embase, Cochrane, and PubMed databases up until December 19, 2021.

STUDY SELECTION

Studies that focused on observed visual changes due to a reduced intake of animal products and that included a minimum of 50 eyes were eligible for inclusion.

DATA EXTRACTION

Two levels of screening, quality assessment, and data extraction were conducted by 2 reviewers independently. The 21 studies identified from 814 unique studies progressed to data extraction and 15 were included in the quantitative analysis using STATA 15.0 fixed-effect and random-effect models computed on the basis of heterogeneity.

RESULTS

The 15 (n = 51 695 participants) assessed the impact of fish consumption, 8 studies (n = 28 753 participants) analyzed the effect of red meat intake, and 3 studies (n = 7723 participants) assessed the impact of omission of skim milk, poultry, and non-meat animal products and the presence of disease incidence as indicated by age-related macular degeneration or cataract development. Meta-analysis indicated regular consumption of fish (odds ratio [OR], 0.70; 95%CI, 0.62-0.79) and skim milk, poultry, and non-meat animal products (OR, 0.70; 95%CI, 0.61-0.79) reduced the risk of age-related eye disease development among adults. Consumption of red meat (OR, 1.41; 95%CI, 1.07-1.86) may increase the risk of age-related eye disease development.

CONCLUSION

A pescatarian diet is associated with the most favorable visual outcomes among adults, whereas consumption of red meat negatively affects ocular health. Results suggest a need for more initiatives promoting a healthy and balanced diet.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42021269925.

An Exploratory Study to Investigate the Utility of Clinical Screening for Neurodegenerative Disease in Age-Related Eye Disease Research

BACKGROUND

Unrecognized neurodegenerative diseases (NDD) in age-related eye disease research studies have the potential to confound vision-specific quality of life and retinal optical coherence tomography (OCT) outcome measures. The aim of this exploratory study was to investigate relationships between NDD screening tools and visual outcome measures in a small cohort of controls from the Colorado Age-Related Macular Degeneration Registry (CO-AMD), to consider the utility of future studies.

METHODS

Twenty-nine controls from the CO-AMD were screened using the Montreal Cognitive Assessment (MoCA), a Colorado Parkinsonian Checklist, and the Lewy Body Composite Risk Score. Univariate and multivariable linear regression modeling was used to assess associations between screening tools and the National Eye Institute Visual Function Questionnaire-25 (VFQ-25) and macular OCT outcome measures, and t tests were used to evaluate outcome measure differences between those with normal vs abnormal MoCA scores.

RESULTS

One patient withdrew. The average age was 72.8 years, and 68% were female patients. Ten participants (36%) had abnormal MoCA scores, and their VFQ-25 scores were only 1 point less and not statistically different than those with normal MoCA scores. Macular OCT volumes and thicknesses for retinal nerve fiber layer (RNFL) and retinal ganglion cell layer were consistently and moderately lower for those with abnormal MoCA scores, and a positive association between MoCA and macular RNFL volume was observed, although differences and regression were not significant. Parkinson screening tests were abnormal for only 4 participants and were not associated with OCT or VFQ-25 measures by regression modeling.

CONCLUSIONS

Given the degree and direction of observed differences, further investigation is warranted regarding the relationship between cognitive screening tools and macular OCT measures in age-related eye disease research, but future investigations regarding the relationship between NDD screening tools and VFQ-25 seem unwarranted.

Is perceived social support more important than visual acuity for clinical depression and anxiety in patients with age-related macular degeneration and diabetic retinopathy?

Objective:

To investigate whether visual acuity has the same importance as a factor of depression and anxiety comparing with other psychological variables, particularly perceived social support, in patients diagnosed with age-related eye diseases, with and without low vision.

Design:

Observational cross-sectional study.

Setting:

Patients attending outpatient appointments at the department of ophthalmology of a general hospital in Portugal.

Subjects:

Patients with age-related macular degeneration and patients with diabetic retinopathy attending routine hospital appointments were recruited for this study.

Measures:

Anxiety and depression were measured using the hospital anxiety and depression scale and perceived social support using the multidimensional scale of perceived social support. Visual acuity was measured with ETDRS charts.

Results:

Of the 71 patients, 53 (75%) were diagnosed with diabetic retinopathy, 37 (52%) were female and age (mean ± SD) was 69 ± 12 years. Acuity in the better seeing eye was 0.41 ± 0.33 logMAR. The mean anxiety score was 4.38 ± 3.82 and depression 4.41 ± 3.39. Clinically significant levels of anxiety were found in 21% (n = 15) of the participants and depression in 18%(n = 13). The total social support score was 5.29 ± 0.61. Significant multivariate regression models were found for anxiety (R² = 0.21, P = 0.016) and for depression (R² = 0.32, P < 0.0001). Social support was independently associated with levels of anxiety and with levels of depression. Gender was independently associated with levels of anxiety.

Conclusion:

This study suggests that patients’ perceived social support might be more important than visual acuity as a factor of clinical depression and anxiety in a sample of age-related eye disease patients.

Prevalence of Vision Loss and Associations With Age-Related Eye Diseases Among Nursing Home Residents Aged ≥65 Years

OBJECTIVES

To examine data from Delaware nursing homes to determine prevalence of age-related eye diseases (AREDs), vision impairment, and blindness and to compare the findings with the results of 11 US investigations of vision and eye health in nursing homes.

DESIGN

This is a cross-sectional, retrospective study of nursing home patients.

SETTING AND PARTICIPANTS

Twenty nursing homes in Delaware participated in the study, yielding comprehensive eye examination records for 2019 study participants.

METHODS

Summary statistics and regression analyses.

RESULTS

The overall prevalence of vision impairment or blindness was 63.8% and was above 60% for each age, sex, and race category. Prevalence of vision impairment or blindness was 68.4% among patients with cataracts, 69.4% among patients with macular degeneration, 70.5% among patients with glaucoma, and 68.4% among patients with diabetic retinopathy. Prevalence of blindness was 14.1%. Among patients with AREDs, prevalence of blindness ranged from 15.0% for patients with cataracts to 22.6% for patients with diabetic retinopathy. When compared with other investigations, we found wide variation in vision and eye factors reported and wide variation in the prevalence of those factors. Only 4 studies diagnosed both AREDs and visual function. Seven studies reported AREDs, and 7 reported vision impairment and/or blindness. Vision impairment or blindness ranged from 29% to 67%; cataract ranged from 32% to 83%; macular degeneration ranged from 4.6% to 70.7%. Glaucoma ranged from 5.3% to 41.4%; diabetic retinopathy ranged from 1.7% to 3.1%.

CONCLUSIONS AND IMPLICATIONS

Comprehensive eye examinations showed that vision impairment and blindness affected 63.8% of nursing home residents. Compared with other studies, there was a wide range of vision factors reported and wide variation in the prevalence of vision impairment or blindness and AREDs. This investigation suggests the importance of eye care in nursing homes and the importance of reporting standard vision and eye health factors to inform policy and practice.

The Consequences of Glaucoma on Mobility and Balance Control in the Older Adults: A Cross-Sectional Study

The aim of the study was to explore the functional impairments and related factors in older adults with moderate to advanced stages of glaucoma. Nineteen patients with glaucoma and 19 participants with no ocular disease performed step test and balance control tasks with analysis of overall stability index and fall risk index. Monocular and binocular Humphrey Visual Field tests were used to estimate visual field defect severity. The International Physical Activity Questionnaire was used to measure physical activity level. Patients with glaucoma showed poorer values for most of the mobility and balance control parameters with medium and large effect sizes (0.3-0.5). Mobility scores in patients were partly associated with their monocular visual field defect (rs = .507, p < .05). Low physical activity was identified as a risk factor for falls (rs = -.453, p < .05) and postural instability (rs = -.457, p < .05). Functional declines in dynamic tasks were not related to glaucoma severity. Older adults with glaucoma display impairment with mobility and balance control compared to controls, associated with the degree of monocular visual field loss and lower daily physical activity.

Visual Impairment, Eye Disease, and the 3-year Incidence of Depressive Symptoms: The Canadian Longitudinal Study on Aging

PURPOSE

Our goal was to explore the longitudinal association between vision-related variables and incident depressive symptoms in a community-dwelling sample of older adults and to examine whether sex, education, or hearing loss act as effect modifiers.

METHODS

A 3-year prospective cohort study was performed using data from the Canadian Longitudinal Study on Aging consisting of 30,097 individuals aged 45-85 years. Visual acuity was evaluated with habitual distance correction using an illuminated Early Treatment of Diabetic Retinopathy Study chart. Visual impairment was defined as binocular presenting visual acuity worse than 20/40. Incident depressive symptoms was defined using a cut-off score of 10 or greater on the Center for Epidemiologic Studies Depression scale. Participants were asked if they had ever had a physician diagnosis of age-related macular degeneration (AMD), glaucoma, or cataract. Multivariable Poisson regression was used.

RESULTS

Of 22,558 participants without depressive symptoms at baseline, 7.7% developed depressive symptoms within 3 years. Cataract was associated with incident depressive symptoms (relative risk = 1.20, 95% confidence interval 1.05, 1.37) after adjusting for age, sex, income, education, partner status, smoking, level of comorbidity, hearing loss, and province. Visual impairment, AMD, and glaucoma were not associated with incident depressive symptoms. No effect modification was detected.

CONCLUSIONS

Our longitudinal data confirm that the risk of depressive symptoms is higher in those who report ever having a cataract. Further research should confirm this and interventions should be considered.

Visual impairment and age-related eye diseases in Florida: Findings from 2006 Behavioral Risk Factors Surveillance System (BRFSS) in Nine states

Purpose

To compare the prevalence of age-related eye disease, visual impairment, and eye care service utilization among adults aged 65 and older in Florida with eight other states.

Methods

In 2006, nine states conducted the visual impairment and access to eye care module using the Behavioral Risk Factors Surveillance System (BRFSS) survey (N = 62,750). Visual impairment was based on self-reported ability to see distant and near objects. Age-related eye diseases including cataract, glaucoma, macular degeneration, and diabetic retinopathy were self-reported with diagnosis confirmed by a health care professional. Eye care visit or examination was assessed by whether a respondent reported an eye visit or dilated eye examination within the past year.

Results

The estimated prevalence of distant and near visual impairment was lower in Florida than in the eight other states (distant: 11.5% vs 15.2%, P < 0.001; near: 22.3% vs 28.7%, P < 0.001). There was no significant difference with the prevalence of age-related macular degeneration and diabetic retinopathy between these two groups. The prevalence of glaucoma and cataract was higher in Florida. The rates of eye care visits (80.5% vs 74.8%, P < 0.01) and dilated eye examinations (74.7% vs 64.0%, P < 0.01) were higher in Florida. After controlling for demographic variables, chronic conditions, insurance, and eye examination, results for elderly in Florida continued to demonstrate less visually impaired.

Conclusion

Fewer elderly in Florida reported visual impairment in spite of comparable or higher prevalence of age-related eye diseases with other states. Health care utilization and health insurance for eye care coverage were also higher in Florida, which may account for the phenomena. More research is needed to investigate the association.