Public Health

Burton MJ, Ramke J, Marques AP, Bourne RRA, Congdon N, Jones I, Ah Tong BAM, Arunga S, Bachani D, Bascaran C, Bastawrous A, Blanchet K, Braithwaite T, Buchan JC, Cairns J, Cama A, Chagunda M, Chuluunkhuu C, Cooper A, Crofts-Lawrence J, Dean WH, Denniston AK, Ehrlich JR, Emerson PM, Evans JR, Frick KD, Friedman DS, Furtado JM, Gichangi MM, Gichuhi S, Gilbert SS, Gurung R, Habtamu E, Holland P, Jonas JB, Keane PA, Keay L, Khanna RC, Khaw PT, Kuper H, Kyari F, Lansingh VC, Mactaggart I, Mafwiri MM, Mathenge W, McCormick I, Morjaria P, Mowatt L, Muirhead D, Murthy GVS, Mwangi N, Patel DB, Peto T, Qureshi BM, Salomão SR, Sarah V, Shilio BR, Solomon AW, Swenor BK, Taylor HR, Wang N, Webson A, West SK, Wong TY, Wormald R, Yasmin S, Yusufu M, Silva JC, Resnikoff S, Ravilla T, Gilbert CE, Foster A, Faal HB. The Lancet Global Health Commission on Global Eye Health: vision beyond 2020. Lancet Glob Health 2021;
Milante RR, Guo X, Neitzel AJ, Kretz AM, Mukherjee RM, Friedman DS, Repka MX, Collins ME. Analysis of vision screening failures in a school-based vision program (2016-19). J AAPOS 2021;Abstract
BACKGROUND: Vision screenings of a school-based program were conducted in state-mandated grades (pre-kindergarten [pre-K] or kindergarten [K], 1st and 8th grade), and nonmandated grades (2nd to 7th). METHODS: During school years 2016-19, 51,593 pre-K to 8th grade students from 123 Baltimore City Public Schools underwent vision screenings, with 85% of the schools qualifying for Free and Reduced Price Meals. Assessments included distance visual acuity, Spot photoscreening, stereopsis, and cover testing. Screening failures were analyzed by grade using aggregate data. Failure rates for mandated and nonmandated grades were compared using a logistic regression model, and visual acuity distributions were analyzed using individual data. RESULTS: Over the 3-year period, 17,414 (34%) of students failed vision screening. Failure rates by grade ranged from 28% to 38%. Children in kindergarten and 3rd grade and higher were statistically more likely to fail screening than those in 1st grade. Reduced visual acuity was the most common reason for failure (91%). Failure rates were significantly higher in nonmandated grades than in state-mandated testing grades (34.7% vs 32.5% [P < 0.001]). Mean visual acuity of all students who failed vision screening was 20/50 in the worse-seeing eye and was 20/40 in the better-seeing eye. CONCLUSIONS: One-third of students failed vision screening. High screening failure rates across all grades suggest that screening in select grade levels, as currently mandated in Maryland schools, is inadequate for detecting vision problems in the low-income communities served by this program.
Mitchell W, Marmamula S, Zebardast N, Ng W, Locascio JJ, Kumbam T, Brahmanandam S, Barrenkala NR. Psychometric validation techniques applied to the IND-VFQ-33 visual function questionnaire: the Hyderabad ocular morbidity in the elderly study (HOMES). BMC Med Res Methodol 2021;21(1):26.Abstract
BACKGROUND: Over 2 billion people suffer from vision impairment or blindness globally, and access to validated visual measurement tools in imperative in accurately describing and managing the burden of eye disease. The present study applies contemporary psychometric validation techniques to the widely used 33-item Indian Visual Function Questionnaire (IND-VFQ-33). METHODS: We first estimated the polychoric correlation between each pair of items. Next, an unrotated and oblique Promax rotated factor analysis, item response theory (IRT, using a graded response model (GRM)), and differential item functioning (DIF) testing were applied to the IND-VFQ-33. We subsequently propose a validated IND-VFQ-33 questionnaire after psychometric testing, data reduction, and adjustment. RESULTS: Exploratory unrotated factor analysis identified two factors; one with a particularly high eigenvalue (18.1) and a second with a lower eigenvalue still above our threshold (1.1). A subsequent oblique Promax factor rotation was undertaken for a 2-factor solution, revealing two moderately correlated factors (+ 0.68) with clinically discrete item loadings onto either Factor 1 (21 items; collectively labelled "daily activities") or Factor 2 (5 items; collectively labelled "bright lights"). IRT confirmed high item discrimination for all remaining items with good separation between difficulty thresholds. We found significant DIF on depression for six items in Factor 1 (all uniform DIF, except item 21 (non-uniform DIF) with no substantive difference in beta thresholds for any item and no substantive difference in expected individual or sum score, by depression at baseline. For Factor 2, only one item demonstrated significant uniform DIF on gender, similarly without major differences in beta thresholds or expected total score between gender at baseline. Consequently, no further item recalibration or reduction was undertaken after IRT and DIF analysis. CONCLUSION: Applying IRT and DIF validation techniques to the IND-VFQ-33 identified 2 discrete factors with 26 uniquely-loading items, clinically representative of difficulty performing daily activities and experiencing difficulty due to bright lights/glare respectively. The proposed modified scale may be useful in evaluating symptomatic disease progression or response to treatment in an Indian population.
Marmamula S, Barrenakala NR, Challa R, Kumbham TR, Modepalli SB, Yellapragada R, Bhakki M, Khanna RC, Friedman DS. Prevalence and risk factors for visual impairment among elderly residents in 'homes for the aged' in India: the Hyderabad Ocular Morbidity in Elderly Study (HOMES). Br J Ophthalmol 2021;105(1):32-36.Abstract
BACKGROUND/AIM: To investigate the prevalence, causes and risk factors of visual impairment (VI) among the elderly in 'home for the aged' in Hyderabad, India. METHODS: Individuals aged ≥60 years were recruited from 41 'homes for the aged'. All participants had complete eye examinations including presenting visual acuity, refraction, slit-lamp examination, intraocular pressure measurement and fundus imaging by trained clinicians. VI was defined as presenting visual acuity worse than 6/18 in the better eye. Multivariate logistic regression was used to determine the risk factors associated with VI. RESULTS: 1512 elderly residents from 41 homes for the aged were enumerated, of whom 1182 (78.1%) were examined. The mean age of examined participants was 75.0 years (SD 8.8 years; range: 60-108 years); 35.4% of those examined were men. The prevalence of VI was 30.1% (95% CI 27.5 to 32.8). The leading cause of VI was cataract (46.3%, n=165), followed by uncorrected refractive error (27.0%, n=96), posterior capsular opacification (14.9%, n=53) and posterior segment disease (6.5%, n=23). Overall, 88.2% of the VI was either treatable or correctable. In multiple logistic regression, those aged 80 years and older (OR: 1.7, p<0.01), living in 'free' homes (OR: 1.5, p<0.01) and who were immobile/bedridden (OR: 3.02, p<0.01) had significantly higher odds of VI. Gender was not associated with VI. CONCLUSIONS: VI was common and largely avoidable in residents of 'homes for the aged' in Hyderabad, India. Screening for vision loss in 'homes for aged' and the provision of appropriate services should become routine practice to achieve the goal of healthy ageing in India.
Singh T, Ichhpujani P, Singh RB. First Line of Defense in COVID-19: Masks in Clinical Practice. Asia Pac J Public Health 2020;:1010539520979928.Abstract
The current evidence suggests that masks are efficacious in limiting the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). Although cloth masks are effective in outdoor environments, there is a consensus about the requirement of N95 masks or respirators when working in close proximity to patients who may be asymptomatic carriers, specifically in ophthalmology clinics, where slit-lamp examinations, noncontact tonometry, and other procedures place the physicians and patients in close proximity with each other. In this report, we review the available evidence regarding the efficacy of different types of masks in clinical practice in ophthalmology.
Naidoo K, Kempen JH, Gichuhi S, Braithwaite T, Casson RJ, Cicinelli MV, Das A, Flaxman SR, Jonas JB, Keeffe JE, Leasher J, Limburg H, Pesudovs K, Resnikoff S, Silvester AJ, Tahhan N, Taylor HR, Wong TY, Bourne RRA, of the of Study VLEGGBD. Prevalence and causes of vision loss in sub-Saharan Africa in 2015: magnitude, temporal trends and projections. Br J Ophthalmol 2020;104(12):1658-1668.Abstract
BACKGROUND: This study aimed to assess the prevalence and causes of vision loss in sub-Saharan Africa (SSA) in 2015, compared with prior years, and to estimate expected values for 2020. METHODS: A systematic review and meta-analysis assessed the prevalence of blindness (presenting distance visual acuity <3/60 in the better eye), moderate and severe vision impairment (MSVI; presenting distance visual acuity <6/18 but ≥3/60) and mild vision impairment (MVI; presenting distance visual acuity <6/12 and ≥6/18), and also near vision impairment (
Mitchell W, Hassall M, Henderson T. Updating the model of eye care for Aboriginal populations in remote Central Australia. Clin Exp Ophthalmol 2020;48(9):1299-1306.Abstract
Eye disease is the third-highest contributor towards health inequality for Aboriginal Australians. Understanding how the Central Australian ophthalmology service addresses complexities of remote eye care is crucial in understanding how expansion can meet current and future needs. The present study analyses findings from the MEDLINE database and Governmental reports, and descriptive information from stakeholders in Central Australia and the Australian Department of Health. We describe the current Central Australian ophthalmology model at three levels; (a) the healthcare service level (specialized primary care, local/outreach optometry and ophthalmology services, and intensive extended surgical weeks), (b) the community level (local community staff, clinics and initiatives, and eye "champions" and mutual support), and (c) the healthcare system level (federal and state government, and private funding). We conclude that building full-time specialist availability, and system-wide approaches to increase patient utilisation, will facilitate overcoming barriers of remoteness, and create enduring improvements in Central Australian eye care and health-inequality.
Marmamula S, Mitchell W, Zebardast N, Locascio J, Barrenkala NR, Kumbham TR, Modepalli SB, Khanna RC, Friedman DS. Impact of Vision Loss on Visual Function Among Elderly Residents in the "Home for the Aged" in India: The Hyderabad Ocular Morbidity in Elderly Study. Transl Vis Sci Technol 2020;9(13):11.Abstract
Purpose: The purpose of this study was to report the association between visual impairment (VI) and self-reported visual difficulty among the elderly in residential care using the Indian Vision Functioning Questionnaire (IND-VFQ-33) psychometrically validated questionnaire. Methods: Participants aged ≥ 60 years were recruited from 41 homes in Hyderabad in South India. All participants underwent detailed eye examination and interviews. Self-reported visual function was assessed using the IND-VFQ-33 questionnaire. Factor Analysis and Item Response Theory (IRT) models were used for analysis. Multivariable regression models were used to investigate associations between derived global difficulty scores versus severity and causes of VI. Presenting visual acuity worse than 6/18 in the better eye was considered as VI. Results: In total, 867 elderly participants completed the INDVFQ-33. Two latent traits ("daily activities" and "visual symptoms") were identified on factor analysis, each with uniquely loading questions. Participants with VI reported significantly higher daily activities difficulty (6 points higher) and visual symptoms difficulty (1.7 points higher) than those without VI ( < 0.05). Those with cataract reported the highest daily activities and visual symptoms difficulty (7.6 points and 2.2 points higher, respectively, < 0.05). Greater severity of VI was associated with increased self-reported difficulty for both factors, and for all causes of VI. Conclusions: We present a psychometrically validated visual questionnaire particularly suited to older adults in residential homes. We show a significant association between cause/severity of VI and difficulty with daily activities and visual symptoms after adjusting for sociodemographic and medical factors. Translational Relevance: Understanding the impact of vision loss on visual functions in the elderly will help in planning and resource allocation for developing early intervention programs for the elderly.
Marmamula S, Barrenkala NR, Khanna RC, Challa R, Bhakki M, Kumbham TR, Modepalli SB, Yellapragada R, Friedman DS. Near vision impairment among the elderly in residential care-the Hyderabad Ocular Morbidity in Elderly Study (HOMES). Eye (Lond) 2020;Abstract
BACKGROUND/OBJECTIVE: To report on the prevalence and risk factors for near vision impairment (NVI) among the elderly in residential care in Telangana State in India. METHODS: Individuals aged ≥60 years were recruited from 41 'home for the aged' centres in Hyderabad, India. All participants had complete eye examinations including presenting and best-corrected visual acuity assessment for distance and near. NVI was defined as binocular presenting near vision worse than N8 (6/15) among those who had a normal presenting distance visual acuity of 6/18 in the better eye. RESULTS: Of the 826 participants, the mean age was 74.4 years (standard deviation-8.4 years), 525 (63.6%) were women, 715 (86.6%) had at least school education. The prevalence of NVI was 51.2% (95% CI: 47.7-54.7) based on presenting vision. On applying multiple logistic regression analysis, the odds of NVI were higher in 80 years and older age (OR: 2.17; 95% CI: 3.44-13.6). Those with school education (OR: 0.58: 95% CI: 0.36-0.94) and higher education (OR: 0.38; 95% CI: 0.21-0.69) had lower odds for NVI. Similarly, those with self-reported diabetes (OR: 0.69; 95% CI: 0.49-0.97), those using spectacles (OR: 0.09; 95% CI: 0.05-0.16), and those who had undergone cataract surgery (OR: 0.51; 95% CI: 0.36-0.74) had lower odds for NVI. CONCLUSIONS: NVI was common among the elderly in residential care in homes for the aged in Hyderabad, India. As most of this NVI is correctable, a routine screening programme and dispensing of spectacles can be undertaken to address this vision loss.
Subburaman G-BB, Kempen JH, Durairaj S, Balakrishnan V, Valaguru V, Namperumalsamy VP, Thulasiraj RD, Gupta S. Making the decision to donate eyes: Perspectives from the families of the deceased in Madurai, India. Indian J Ophthalmol 2020;68(10):2094-2098.Abstract
Purpose: To identify factors affecting family members' decision whether to donate eye organs. Methods: A community-based case-control study based on in-home interviews with families of deceased individuals who had or had not donated eye organs, in Madurai district, Tamil Nadu, India. Data collected were knowledge and awareness of eye donations, whether the deceased individual had expressed or pledged willingness to donate, and family members' attitudes and willingness to donate their own eye organs. Results: Seventy-six families of donors and 256 families of non-donors completed the survey. Multivariable analysis showed that the following variables were significantly associated with a donation: age, whether the deceased had registered for eye donation, pre-expressed willingness of deceased to donate, whether family members personally know beneficiaries of eye donations, and higher score on a scale evaluating knowledge and awareness about eye donation. The majority of donors' families (71%) had been encouraged by someone to donate. Among non-donor families, a substantially larger fraction (52.8%) indicated they would have donated had someone reminded or encouraged them to do so, in comparison with those who indicated lack of awareness or knowledge (14.5%). Conclusion: Community programs are likely to be effective if they encourage individuals to pledge their eyes or express their willingness to donate their eyes to family members in advance of death; they increase public awareness of the value of eye donation. A friend, family member, neighbor or counselor approaching bereaved families and having a dialogue about eye donation would substantially increase the probability of a decision to donate.
Kempen JH, Abashawl A, Suga HK, Nigussie Difabachew M, Kempen CJ, Tesfaye Debele M, Menkir AA, Assefa MT, Asfaw EH, Habtegabriel LB, Sitotaw Addisie Y, Nilles EJ, Longenecker JC. SARS-CoV-2 Serosurvey in Addis Ababa, Ethiopia. Am J Trop Med Hyg 2020;103(5):2022-2023.Abstract
In a serosurvey of asymptomatic people from the general population recruited from a clinical laboratory in May 2020 in Addis Ababa, Ethiopia, three of 99 persons tested positive for SARS-CoV-2 IgG (3.0%, 95% binomial exact confidence interval: 0.6-8.6%). Taking into account pretest probability and the sampling scheme, the range of plausible population prevalence values was approximately 1.0-8.4%. These results suggest that a larger number of people have been infected than the counts detected by surveillance to date; nevertheless, the results suggest the large majority of the general population in Addis Ababa currently is susceptible to COVID-19.
Marmamula S, Barrenkala NR, Challa R, Kumbham TR, Modepalli SB, Yellapragada R, Bhakki M, Friedman DS, Khanna RC. Falls and visual impairment among elderly residents in 'homes for the aged' in India. Sci Rep 2020;10(1):13389.Abstract
We evaluated the prevalence of falls and their association with visual impairment (VI) in elderly residents in 'homes for the aged' in Hyderabad, India. Participants aged ≥ 60 years were recruited from 41 homes, and a comprehensive eye examination was conducted. Interviews were conducted to collect personal and demographic information, systemic health status, fear of falling, depression, and history of falls in the last year. VI categories included low vision (presenting visual acuity worse than 6/18 to 3/60) and blindness (presenting visual acuity worse than 3/60). The data of 1,074 participants were analysed. The mean age was 74.4 years (standard deviation:8.7 years); 63.9% were women, 19.4% had no formal education, 28.1% were diabetic and 56.9% were hypertensive. The annual prevalence of falls was 29.1% (95% CI: 26.4-32.0). Multivariable analysis showed those with VI had significantly higher odds of falls (Odds Ratio:1.47; p = 0.043). The prevalence of falls was higher among those with VI due to uncorrected refractive errors. We found a very high prevalence of falls in elderly individuals living in 'homes for the aged' in Hyderabad, India. Addressing VI can result in fewer falls and contribute to healthy aging in India.
Zheng Q, Jones FK, Leavitt SV, Ung L, Labrique AB, Peters DH, Lee EC, Azman AS, Azman AS. HIT-COVID, a global database tracking public health interventions to COVID-19. Sci Data 2020;7(1):286.Abstract
The COVID-19 pandemic has sparked unprecedented public health and social measures (PHSM) by national and local governments, including border restrictions, school closures, mandatory facemask use and stay at home orders. Quantifying the effectiveness of these interventions in reducing disease transmission is key to rational policy making in response to the current and future pandemics. In order to estimate the effectiveness of these interventions, detailed descriptions of their timelines, scale and scope are needed. The Health Intervention Tracking for COVID-19 (HIT-COVID) is a curated and standardized global database that catalogues the implementation and relaxation of COVID-19 related PHSM. With a team of over 200 volunteer contributors, we assembled policy timelines for a range of key PHSM aimed at reducing COVID-19 risk for the national and first administrative levels (e.g. provinces and states) globally, including details such as the degree of implementation and targeted populations. We continue to maintain and adapt this database to the changing COVID-19 landscape so it can serve as a resource for researchers and policymakers alike.
Hu A, Gu SZ, Friedman DS, Cao K, Wang N. Six-Year Incidence and Causes of Low Vision and Blindness in a Rural Chinese Adult Population: The Handan Eye Study. Ophthalmic Epidemiol 2020;:1-9.Abstract
PURPOSE: To determine the six-year incidence, risk factors, and causes of visual impairment in a Chinese population. METHODS: This was a population-based study of eye disease in Chinese adults in a rural district of Handan in China. 6,830 individuals were invited to participate in 2006 and 5,394 returned for follow-up in 2012. All participants underwent standardized eye examinations. Visual impairment was defined according to WHO criteria. The incidence of visual impairment was age- and gender-standardized to the 2010 China Census. Multivariable logistic regression analysis was used to determine risk factors for visual impairment. RESULTS: The leading causes of visual impairment were cataract and refractive error. Based on (PVA), the six-year incidence rates of low vision and blindness were 5.2% and 0.5%, respectively. Incidence of low vision was associated with older age ( < .001), less education ( < .001), diabetes ( < .05), and lower BMI ( < .001). The incidence of blindness was associated with diabetes ( < .05). Based on (BCVA), the six-year incidence rates of low vision and blindness were 0.8% and 0.1%, respectively. Incidence of low vision was associated with older age ( < .001) and lower BMI ( < .05). None of these factors were associated with the incidence of blindness. CONCLUSION: In Handan, the incidence of visual impairment was high and associated with older age, less education, diabetes, and lower BMI. The majority of cases were due to unoperated cataract and uncorrected refractive error, reflecting the need for improved eye care in this region.
Keel S, Evans JR, Block S, Bourne R, Calonge M, Cheng C-Y, Friedman DS, Furtado JM, Khanna RC, Mathenge W, Mariotti S, Matoto E, Müller A, Rabiu MM, Rasengane T, Zhao J, Wormald R, Cieza A. Strengthening the integration of eye care into the health system: methodology for the development of the WHO package of eye care interventions. BMJ Open Ophthalmol 2020;5(1):e000533.Abstract
Objective: To describe the rational for, and the methods that will be employed to develop, the WHO package of eye care interventions (PECI). Methods and analysis: The development of the package will be conducted in four steps: (1) selection of eye conditions (for which interventions will be included in the package) based on epidemiological data on the causes of vision impairment and blindness, prevalence estimates of eye conditions and health facility data; (2) identification of interventions and related evidence for the selected eye conditions from clinical practice guidelines and high-quality systematic reviews by a technical working group; (3) expert agreement on the inclusion of eye care interventions in the package and the description of resources required for the provision of the selected interventions; and (4) peer review. The project will be led by the WHO Vision Programme in collaboration with Cochrane Eyes and Vision. A Technical Advisory Group, comprised of public health and clinical experts in the field, will provide technical input throughout all stages of development. Results: After considering the feedback of Technical Advisory Group members and reviewing-related evidence, a final list of eye conditions for which interventions will be included in the package has been collated. Conclusion: The PECI will support Ministries of Health in prioritising, planning, budgeting and integrating eye care interventions into health systems. It is anticipated that the PECI will be available for use in 2021.