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PurposeGenetic variants identified through population-based genome-wide studies are generally of high frequency, exerting their action in the central part of the refractive error spectrum. However, the power to identify associations with variants of lower minor allele frequency is greatly reduced, requiring considerable sample sizes. Here we aim to assess the impact of rare variants on genetic variation of refractive errors in a very large general population cohort.MethodsGenetic association analyses of non-cyclopaedic autorefraction calculated as mean spherical equivalent (SPHE) used whole-exome sequence genotypic information from 50,893 unrelated participants in the UK Biobank of European ancestry. Gene-based analyses tested for association with SPHE using an optimised SNP-set kernel association test (SKAT-O) restricted to rare variants (minor allele frequency < 1%) within protein-coding regions of the genome. All models were adjusted for age, sex and common lead variants within the same locus reported by previous genome-wide association studies. Potentially causal markers driving association at significant loci were elucidated using sensitivity analyses by sequentially dropping the most associated variants from gene-based analyses.ResultsWe found strong statistical evidence for association of SPHE with the SIX6 (p-value = 2.15 x 10-10, or Bonferroni-Corrected p = 4.41x10-06) and the CRX gene (p-value = 6.65 x 10-08, or Bonferroni-Corrected p = 0.001). The SIX6 gene codes for a transcription factor believed to be critical to the eye, retina and optic disc development and morphology, while CRX regulates photoreceptor specification and expression of over 700 genes in the retina. These novel associations suggest an important role of genes involved in eye morphogenesis in refractive error.ConclusionThe results of our study support previous research highlighting the importance of rare variants to the genetic risk of refractive error. We explain some of the origins of the genetic signals seen in GWAS but also report for the first time a completely novel association with the CRX gene.

This study investigated temporal trends in the epidemiology of primary myopia and associations with key environmental risk factors in a UK population. Data were collected at recruitment (non-cycloplegic autorefraction, year of birth, sex, ethnicity, highest educational attainment, reason and age of first wearing glasses and history of eye disease) from 107,442 UK Biobank study participants aged 40 to 69 years, born between 1939 and 1970. Myopia was defined as mean spherical equivalent (MSE) ≤-1 dioptre (D). Temporal changes in myopia frequency by birth cohort (5-year bands using date of birth) and associations with environmental factors were analysed, distinguishing both type (childhood-onset,

BackgroundChildhood visual impairment (VI) has a profound impact on many aspects of childhood and adolescence. This is well-documented in cross-sectional and/or quantitative studies utilizing self-report instruments which compare children with and without VI. Young people's views on the experience of growing up with VI as a developmental, change-driven process remain largely unexplored.MethodsAs part of our broader research programme on quality of life of visually impaired children and young people in the United Kingdom, in-depth, semi-structured interviews were conducted between March and June 2015, with a stratified sample of 17 young people with VI, aged 16-19 years. An age-sensitive, empirically-based topic guide encouraged retrospective reflections on participants' experiences of growing up with VI, including age-normative and vision-specific challenges.ResultsDescriptions of growing up with VI largely centered on an overarching higher-order theme labelled becoming me. Four themes representing everyday activities, attitudes, preferences and perceptions in relation to i) social relationships, ii) independence and responsibilities, iii) the future, and iv) rising to challenges emerged and were used by participants in their description of three stages in which they developed a sense of self: i) laying the foundations, ii) testing the waters, and iii) this is me. Differences in manifestation of VI influenced how young people made sense of their experiences and their sense of self.ConclusionsFindings are discussed in relation to normative and vision-specific changes in psychosocial development during adolescence, including the development of identity. They highlight the need for ongoing monitoring of subjective well-being in a clinical population with a unique early life course trajectory.

Background/objectivesRoutine use of patient-reported outcome measures (PROMs) to assess quality of health care systems is mandated in many countries and has been implemented successfully in many specialities. Ophthalmology currently lags behind. To support and inform future implementation, we investigated paediatric ophthalmic clinicians' experience of, and future training needs for, using child-appropriate vision PROMs and their views about the barriers and enablers to future routine implementation in clinical practice.MethodsWe conducted a pilot study, using an online survey to elicit the experience, attitudes, training needs and perceptions of barriers and enablers to routine PROMs use of ophthalmic health professionals in the Paediatric Ophthalmology Department at Great Ormond Street Hospital, London. A focus-group was undertaken to discuss survey results and preferences regarding presentation of PROM data. Analysis comprised descriptive statistics, presented alongside complementary qualitative data.ResultsEighteen clinicians in the department completed the survey. Twenty-seven took part in the focus group. Clinicians had limited experience of using PROMs but high confidence in the potential positive impact on communication with patients, monitoring chronic conditions and clinical decision-making. Clinicians identified operational issues (collection and analysis of data) and impact (interpretation and application of data) as the two key areas for consideration. Training and information requirements before implementation were clearly articulated, alongside the benefits of using digital/electronic data capture ahead of consultations to allow efficiency and automated analysis, and presentation in an appropriate visual format alongside clinical data to ensure meaningful use.ConclusionThe findings of this pilot study of ophthalmic clinicians working in a specialist paediatric ophthalmology department, suggest that ophthalmic clinicians recognise the potential benefits of routine PROMs use in clinical practice. Together with existing literature outside ophthalmology relating to overcoming barriers and exploiting enablers to routine implementation, findings may be applicable in planning routine PROM implementation in paediatric ophthalmology.

PURPOSE:To report piloting and initial validation of the VQoL_CYP, a novel age-appropriate vision-related quality of life (VQoL) instrument for self-reporting by children with visual impairment (VI). METHODS:Participants were a random patient sample of children with VI aged 10-15 years. 69 patients, drawn from patient databases at Great Ormond Street Hospital and Moorfields Eye Hospital, United Kingdom, participated in piloting of the draft 47-item VQoL instrument, which enabled preliminary item reduction. Subsequent administration of the instrument, alongside functional vision (FV) and generic health-related quality of life (HRQoL) self-report measures, to 101 children with VI comprising a nationally representative sample enabled further item reduction and evaluation of psychometric properties using Rasch analysis. Construct validity was assessed through Pearson correlation coefficients. RESULTS:Item reduction through piloting (8 items removed for skewness and individual item response pattern) and validation (1 item removed for skewness and 3 for misfit in Rasch) produced a 35-item scale, with fit values within acceptable limits, no notable differential item functioning, good measurement precision, ordered response categories and acceptable targeting in Rasch. The VQoL_CYP showed good construct validity, correlating strongly with HRQoL scores, moderately with FV scores but not with acuity. CONCLUSIONS:Robust child-appropriate self-report VQoL measures for children with VI are necessary for understanding the broader impacts of living with a visual disability, distinguishing these from limited functioning per se. Future planned use in larger patient samples will allow further psychometric development of the VQoL_CYP as an adjunct to objective outcomes assessment.

PURPOSE:To report the methodology and findings of a large scale investigation of burden and distribution of refractive error, from a contemporary and ethnically diverse study of health and disease in adults, in the UK. METHODS:U K Biobank, a unique contemporary resource for the study of health and disease, recruited more than half a million people aged 40-69 years. A subsample of 107,452 subjects undertook an enhanced ophthalmic examination which provided autorefraction data (a measure of refractive error). Refractive error status was categorised using the mean spherical equivalent refraction measure. Information on socio-demographic factors (age, gender, ethnicity, educational qualifications and accommodation tenure) was reported at the time of recruitment by questionnaire and face-to-face interview. RESULTS:Fifty four percent of participants aged 40-69 years had refractive error. Specifically 27% had myopia (4% high myopia), which was more common amongst younger people, those of higher socio-economic status, higher educational attainment, or of White or Chinese ethnicity. The frequency of hypermetropia increased with age (7% at 40-44 years increasing to 46% at 65-69 years), was higher in women and its severity was associated with ethnicity (moderate or high hypermetropia at least 30% less likely in non-White ethnic groups compared to White). CONCLUSIONS:Refractive error is a significant public health issue for the UK and this study provides contemporary data on adults for planning services, health economic modelling and monitoring of secular trends. Further investigation of risk factors is necessary to inform strategies for prevention. There is scope to do this through the planned longitudinal extension of the UK Biobank study.

PURPOSE:To investigate feasibility, reliability and repeatability of perimetry in children. METHODS:A prospective, observational study recruiting 154 children aged 5-15 years, without an ophthalmic condition that affects the visual field (controls), identified consecutively between May 2012 and November 2013 from hospital eye clinics. Perimetry was undertaken in a single sitting, with standardised protocols, in a randomised order using the Humphrey static (SITA 24-2 FAST), Goldmann and Octopus kinetic perimeters. Data collected included test duration, subjective experience and test quality (incorporating examiner ratings on comprehension of instructions, fatigue, response to visual and auditory stimuli, concentration and co-operation) to assess feasibility and reliability. Testing was repeated within 6 months to assess repeatability. RESULTS:Overall feasibility was very high (Goldmann=96.1%, Octopus=89% and Humphrey=100% completed the tests). Examiner rated reliability was 'good' in 125 (81.2%) children for Goldmann, 100 (64.9%) for Octopus and 98 (63.6%) for Humphrey perimetry. Goldmann perimetry was the most reliable method in children under 9 years of age. Reliability improved with increasing age (multinomial logistic regression (Goldmann, Octopus and Humphrey), p

Refractive error (RE) is a complex, multifactorial disorder characterized by a mismatch between the optical power of the eye and its axial length that causes object images to be focused off the retina. The two major subtypes of RE are myopia (nearsightedness) and hyperopia (farsightedness), which represent opposite ends of the distribution of the quantitative measure of spherical refraction. We performed a fixed effects meta-analysis of genome-wide association results of myopia and hyperopia from 9 studies of European-derived populations: AREDS, KORA, FES, OGP-Talana, MESA, RSI, RSII, RSIII and ERF. One genome-wide significant region was observed for myopia, corresponding to a previously identified myopia locus on 8q12 (p = 1.25×10(-8)), which has been reported by Kiefer et al. as significantly associated with myopia age at onset and Verhoeven et al. as significantly associated to mean spherical-equivalent (MSE) refractive error. We observed two genome-wide significant associations with hyperopia. These regions overlapped with loci on 15q14 (minimum p value = 9.11×10(-11)) and 8q12 (minimum p value 1.82×10(-11)) previously reported for MSE and myopia age at onset. We also used an intermarker linkage- disequilibrium-based method for calculating the effective number of tests in targeted regional replication analyses. We analyzed myopia (which represents the closest phenotype in our data to the one used by Kiefer et al.) and showed replication of 10 additional loci associated with myopia previously reported by Kiefer et al. This is the first replication of these loci using myopia as the trait under analysis. "Replication-level" association was also seen between hyperopia and 12 of Kiefer et al.'s published loci. For the loci that show evidence of association to both myopia and hyperopia, the estimated effect of the risk alleles were in opposite directions for the two traits. This suggests that these loci are important contributors to variation of refractive error across the distribution.

Background and objectives: Early detection is critical to achieving optimal outcomes in children with congenital cataract. We hypothesized that detection of congenital cataract in preterm infants would be delayed compared with term/post-term peers due to delayed delivery of whole population child health interventions. Methods: Secondary analysis of data using a nested case-control study approach in a prospective population-based cohort study. Inclusion criteria comprised children diagnosed with congenital cataract requiring surgical intervention during the first two years of life in UK and Ireland in 2009 and 2010. Association between late detection (after eight weeks post-natal age, ie outside the neonatal and infant eye national screening programme) of cataract and preterm birth (gestational age less than 37 weeks) was assessed using multivariable logistic regression. Results: Of 186 children with congenital cataract, 17 children were born preterm (9%, gestational age range 24–37weeks). Neonatal detection occurred in 64/186 (34%), and late detection in 64 children (34%). Late detection was independently associated with premature birth, specifically moderate/late preterm birth (adjusted odds ratio 3.0, 95%CI 1.1 to 8.5). Conclusions: Our findings suggest that, despite enhanced eye surveillance being recommended for those born moderate/late preterm (32+ weeks gestational age, ie not eligible for retinopathy of prematurity screening), congenital cataract is not being effectively detected through the routine screening programme for this vulnerable group. It is necessary to improve the effectiveness of the screening programme, and care must be taken to ensure that competing health care needs of preterm children do not prevent universal child health interventions. [ABSTRACT FROM AUTHOR]

Purpose: Genetic variants identified through population-based genome-wide studies are generally of high frequency, exerting their action in the central part of the refractive error spectrum. However, the power to identify associations with variants of lower minor allele frequency is greatly reduced, requiring considerable sample sizes. Here we aim to assess the impact of rare variants on genetic variation of refractive errors in a very large general population cohort. Methods: Genetic association analyses of non-cyclopaedic autorefraction calculated as mean spherical equivalent (SPHE) used whole-exome sequence genotypic information from 50,893 unrelated participants in the UK Biobank of European ancestry. Gene-based analyses tested for association with SPHE using an optimised SNP-set kernel association test (SKAT-O) restricted to rare variants (minor allele frequency < 1%) within protein-coding regions of the genome. All models were adjusted for age, sex and common lead variants within the same locus reported by previous genome-wide association studies. Potentially causal markers driving association at significant loci were elucidated using sensitivity analyses by sequentially dropping the most associated variants from gene-based analyses. Results: We found strong statistical evidence for association of SPHE with the SIX6 (p-value = 2.15 x 10−10, or Bonferroni-Corrected p = 4.41x10-06) and the CRX gene (p-value = 6.65 x 10−08, or Bonferroni-Corrected p = 0.001). The SIX6 gene codes for a transcription factor believed to be critical to the eye, retina and optic disc development and morphology, while CRX regulates photoreceptor specification and expression of over 700 genes in the retina. These novel associations suggest an important role of genes involved in eye morphogenesis in refractive error. Conclusion: The results of our study support previous research highlighting the importance of rare variants to the genetic risk of refractive error. We explain some of the origins of the genetic signals seen in GWAS but also report for the first time a completely novel association with the CRX gene. [ABSTRACT FROM AUTHOR]

This study investigated temporal trends in the epidemiology of primary myopia and associations with key environmental risk factors in a UK population. Data were collected at recruitment (non-cycloplegic autorefraction, year of birth, sex, ethnicity, highest educational attainment, reason and age of first wearing glasses and history of eye disease) from 107,442 UK Biobank study participants aged 40 to 69 years, born between 1939 and 1970. Myopia was defined as mean spherical equivalent (MSE) ≤-1 dioptre (D). Temporal changes in myopia frequency by birth cohort (5-year bands using date of birth) and associations with environmental factors were analysed, distinguishing both type (childhood-onset, <18 years versus adult-onset) and severity (three categories: low -1.00 to -2.99D, moderate -3.00 to -5.99D or high ≥-6.00D). Overall myopia frequency increased from 20.0% in the oldest cohort (births 1939–1944) to 29.2% in the youngest (1965–1970), reflecting a relatively higher increase in frequency of adult-onset and low myopia. Childhood-onset myopia peaked in participants born in 1950–54, adult-onset myopia peaked in the cohort born a decade later. The distribution of MSE only shifted for childhood-onset myopia (median: -3.8 [IQR -2.4, -5.4] to -4.4 [IQR -3.0, -6.2]). The magnitude of the association between higher educational attainment (proxy for educational intensity) and myopia overall increased over time (adjusted Odds Ratio (OR) 2.7 [2.5, 2.9] in the oldest versus 4.2 [3.3, 5.2] in the youngest cohort), being substantially greater for childhood-onset myopia (OR 3.3 [2.8, 4.0] to 8.0 [4.2, 13]). Without delineating childhood-onset from adult-onset myopia, important temporal trends would have been obscured. The differential impact of educational experience/intensity on both childhood-onset and high myopia, amplified over time, suggests a cohort effect in gene-environment interaction with potential for increasing myopia frequency if increasing childhood educational intensity is unchecked. However, historical plateauing of myopia frequency does suggest some potential for effective intervention. [ABSTRACT FROM AUTHOR]

Background: Childhood visual impairment (VI) has a profound impact on many aspects of childhood and adolescence. This is well-documented in cross-sectional and/or quantitative studies utilizing self-report instruments which compare children with and without VI. Young people's views on the experience of growing up with VI as a developmental, change-driven process remain largely unexplored. Methods: As part of our broader research programme on quality of life of visually impaired children and young people in the United Kingdom, in-depth, semi-structured interviews were conducted between March and June 2015, with a stratified sample of 17 young people with VI, aged 16–19 years. An age-sensitive, empirically-based topic guide encouraged retrospective reflections on participants' experiences of growing up with VI, including age-normative and vision-specific challenges. Results: Descriptions of growing up with VI largely centered on an overarching higher-order theme labelled becoming me. Four themes representing everyday activities, attitudes, preferences and perceptions in relation to i) social relationships, ii) independence and responsibilities, iii) the future, and iv) rising to challenges emerged and were used by participants in their description of three stages in which they developed a sense of self: i) laying the foundations, ii) testing the waters, and iii) this is me. Differences in manifestation of VI influenced how young people made sense of their experiences and their sense of self. Conclusions: Findings are discussed in relation to normative and vision-specific changes in psychosocial development during adolescence, including the development of identity. They highlight the need for ongoing monitoring of subjective well-being in a clinical population with a unique early life course trajectory. [ABSTRACT FROM AUTHOR]

Background/Objectives: Routine use of patient-reported outcome measures (PROMs) to assess quality of health care systems is mandated in many countries and has been implemented successfully in many specialities. Ophthalmology currently lags behind. To support and inform future implementation, we investigated paediatric ophthalmic clinicians' experience of, and future training needs for, using child-appropriate vision PROMs and their views about the barriers and enablers to future routine implementation in clinical practice. Methods: We conducted a pilot study, using an online survey to elicit the experience, attitudes, training needs and perceptions of barriers and enablers to routine PROMs use of ophthalmic health professionals in the Paediatric Ophthalmology Department at Great Ormond Street Hospital, London. A focus-group was undertaken to discuss survey results and preferences regarding presentation of PROM data. Analysis comprised descriptive statistics, presented alongside complementary qualitative data. Results: Eighteen clinicians in the department completed the survey. Twenty-seven took part in the focus group. Clinicians had limited experience of using PROMs but high confidence in the potential positive impact on communication with patients, monitoring chronic conditions and clinical decision-making. Clinicians identified operational issues (collection and analysis of data) and impact (interpretation and application of data) as the two key areas for consideration. Training and information requirements before implementation were clearly articulated, alongside the benefits of using digital/electronic data capture ahead of consultations to allow efficiency and automated analysis, and presentation in an appropriate visual format alongside clinical data to ensure meaningful use. Conclusion: The findings of this pilot study of ophthalmic clinicians working in a specialist paediatric ophthalmology department, suggest that ophthalmic clinicians recognise the potential benefits of routine PROMs use in clinical practice. Together with existing literature outside ophthalmology relating to overcoming barriers and exploiting enablers to routine implementation, findings may be applicable in planning routine PROM implementation in paediatric ophthalmology. [ABSTRACT FROM AUTHOR]

Purpose: To describe corneal astigmatism in the UK Biobank population and to look for associations with other biometric variables and socio-demographic factors. Methods: This analysis included a subsample of 107,452 participants of the UK Biobank study who underwent an enhanced ophthalmic examination including autorefractor keratometry (Tomey RC 5000, Tomey Corp., Nagoya, Japan). Participants were recruited from across the United Kingdom between 2006 and 2010, and all were between 40 to 69 years. After quality control and applying relevant exclusions, data on corneal astigmatism on 83,751 participants were included for analysis. Potential associations were tested through univariable regression and significant parameters carried forward for multivariable analysis. Results: In univariable analysis, the characteristics significantly associated with higher corneal astigmatism (P<0.001), by order of magnitude were, female gender, white ethnicity, lighter skin colour, use of UV protection, lower alcohol intake, lower corneal-compensated intraocular pressure (ccIOP), older age at completion of education, younger age, higher Townsend deprivation index, lower height and lower systolic blood pressure. After inclusion in the multivariable analysis, gender, skin colour, alcohol intake, age at completion of full-time education, ccIOP, age and Townsend deprivation score remained significant (all P<0.001). Increased corneal astigmatism was also found to be significantly associated with amblyopia or strabismus. Conclusions: This analysis confirms previous associations with astigmatism such as younger age and female gender, and identified novel risk factors including lighter skin colour, lower alcohol intake, later age having completed full time education later, lower ccIOP and higher Townsend deprivation index. Further research is needed to investigate these novel associations. [ABSTRACT FROM AUTHOR]

Refractive error (RE) is a complex, multifactorial disorder characterized by a mismatch between the optical power of the eye and its axial length that causes object images to be focused off the retina. The two major subtypes of RE are myopia (nearsightedness) and hyperopia (farsightedness), which represent opposite ends of the distribution of the quantitative measure of spherical refraction. We performed a fixed effects meta-analysis of genome-wide association results of myopia and hyperopia from 9 studies of European-derived populations: AREDS, KORA, FES, OGP-Talana, MESA, RSI, RSII, RSIII and ERF. One genome-wide significant region was observed for myopia, corresponding to a previously identified myopia locus on 8q12 (p = 1.25×10−8), which has been reported by Kiefer et al. as significantly associated with myopia age at onset and Verhoeven et al. as significantly associated to mean spherical-equivalent (MSE) refractive error. We observed two genome-wide significant associations with hyperopia. These regions overlapped with loci on 15q14 (minimum p value = 9.11×10−11) and 8q12 (minimum p value 1.82×10−11) previously reported for MSE and myopia age at onset. We also used an intermarker linkage- disequilibrium-based method for calculating the effective number of tests in targeted regional replication analyses. We analyzed myopia (which represents the closest phenotype in our data to the one used by Kiefer et al.) and showed replication of 10 additional loci associated with myopia previously reported by Kiefer et al. This is the first replication of these loci using myopia as the trait under analysis. “Replication-level” association was also seen between hyperopia and 12 of Kiefer et al.'s published loci. For the loci that show evidence of association to both myopia and hyperopia, the estimated effect of the risk alleles were in opposite directions for the two traits. This suggests that these loci are important contributors to variation of refractive error across the distribution. [ABSTRACT FROM AUTHOR]