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1.
Invest Ophthalmol Vis Sci ; 64(14): 38, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-38010695

RESUMO

Purpose: The purpose of this study was to investigate if education contributes to the risk of myopia because educational activities typically occur indoors or because of other factors, such as prolonged near viewing. Methods: This was a two-sample Mendelian randomization study. Participants were from the UK Biobank, Avon Longitudinal Study of Parents and Children, and Generation R. Genetic variants associated with years spent in education or time spent outdoors were used as instrumental variables. The main outcome measures were: (1) spherical equivalent refractive error attained by adulthood, and (2) risk of an early age-of-onset of spectacle wear (EAOSW), defined as an age-of-onset of 15 years or below. Results: Time spent outdoors was found to have a small genetic component (heritability 9.8%) that tracked from childhood to adulthood. A polygenic score for time outdoors was associated with children's time outdoors; a polygenic score for years spent in education was inversely associated with children's time outdoors. Accounting for the relationship between time spent outdoors and myopia in a multivariable Mendelian randomization analysis reduced the size of the causal effect of more years in education on myopia to -0.17 diopters (D) per additional year of formal education (95% confidence interval [CI] = -0.32 to -0.01) compared with the estimate from a univariable Mendelian randomization analysis of -0.27 D per year (95% CI = -0.41 to -0.13). Comparable results were obtained for the outcome EAOSW. Conclusions: Accounting for the effects of time outdoors reduced the estimated causal effect of education on myopia by 40%. These results suggest about half of the relationship between education and myopia may be mediated by children not being outdoors during schooling.


Assuntos
Atividades de Lazer , Miopia , Adolescente , Criança , Humanos , Adulto Jovem , Escolaridade , Estudos Longitudinais , Miopia/epidemiologia , Miopia/genética , Fatores de Risco , Análise da Randomização Mendeliana
2.
Neonatology ; 120(6): 690-698, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37678198

RESUMO

BACKGROUND: Post-haemorrhagic ventricular dilatation (PHVD) is commonly seen in extremely preterm babies, carries significant morbidity, and may cause neonatal mortality. There is a lack of literature on the subsequent health-related quality of life (HRQoL) in childhood. The aim of this work was to assess the quality of life of preterm babies after PHVD at 10 years of age using two validated questionnaires. METHODS: Children with PHVD were assessed as part of the 10-year follow-up of the drainage, irrigation, and fibrinolytic therapy trial. The HRQoL outcome was measured using parent-reported EQ-5D-5L and HUI-3 questionnaires. Both questionnaires produce a summary score anchored at 1 (best health) and 0 (equivalent to death). RESULTS: Median scores at follow-up were 0.65 (IQR 0.36-0.84; n = 44) for the EQ-5D-5L and 0.52 (IQR 0.22-0.87; n = 51) for the HUI-3. Similar proportions had a score below 0.2 (HRQoL [20%], HUI-3 [21%]), while 20% had a HRQoL score above 0.80 compared to 34% using HUI-3. The most severe problems from the EQ-5D-5L were reported in the self-care, mobility, and activity domains, while the HUI-3 reported worse problems in ambulation, cognition, and dexterity domains. Infants with worse (grade 4) intraventricular haemorrhage had poorer HRQoL than those with grade 3 bleeds. CONCLUSION: Children who survive to 10 years of age after PHVD have on average lower HRQoL than their peers. However, the reported range is wide, with a quarter of the children having scores above 0.87 (similar to population norms), while a fifth have very low HRQol scores. Impact was not uniform across domains, with mobility/ambulation a concern across both measures.


Assuntos
Hemorragia Cerebral , Qualidade de Vida , Recém-Nascido , Lactente , Criança , Humanos , Estudos de Coortes , Seguimentos , Dilatação , Inquéritos e Questionários , Lactente Extremamente Prematuro
3.
Front Physiol ; 14: 1251042, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37745231

RESUMO

Feast-fast cycles allow animals to live in seasonal environments by promoting fat storage when food is plentiful and lipolysis when food is scarce. Fat-storing hibernators have mastered this cycle over a circannual schedule, by undergoing extreme fattening to stockpile fuel for the ensuing hibernation season. Insulin is intrinsic to carbohydrate and lipid metabolism and is central to regulating feast-fast cycles in mammalian hibernators. Here, we examine glucose and insulin dynamics across the feast-fast cycle in fat-tailed dwarf lemurs, the only obligate hibernator among primates. Unlike cold-adapted hibernators, dwarf lemurs inhabit tropical forests in Madagascar and hibernate under various temperature conditions. Using the captive colony at the Duke Lemur Center, we determined fasting glucose and insulin, and glucose tolerance, in dwarf lemurs across seasons. During the lean season, we maintained dwarf lemurs under stable warm, stable cold, or fluctuating ambient temperatures that variably included food provisioning or deprivation. Overall, we find that dwarf lemurs can show signatures of reversible, lean-season insulin resistance. During the fattening season prior to hibernation, dwarf lemurs had low glucose, insulin, and HOMA-IR despite consuming high-sugar diets. In the active season after hibernation, glucose, insulin, HOMA-IR, and glucose tolerance all increased, highlighting the metabolic processes at play during periods of weight gain versus weight loss. During the lean season, glucose remained low, but insulin and HOMA-IR increased, particularly in animals kept under warm conditions with daily food. Moreover, these lemurs had the greatest glucose intolerance in our study and had average HOMA-IR values consistent with insulin resistance (5.49), while those without food under cold (1.95) or fluctuating (1.17) temperatures did not. Remarkably low insulin in dwarf lemurs under fluctuating temperatures raises new questions about lipid metabolism when animals can passively warm and cool rather than undergo sporadic arousals. Our results underscore that seasonal changes in insulin and glucose tolerance are likely hallmarks of hibernating mammals. Because dwarf lemurs can hibernate under a range of conditions in captivity, they are an emerging model for primate metabolic flexibility with implications for human health.

4.
J Vet Diagn Invest ; 35(5): 514-520, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37381927

RESUMO

Although many studies have characterized catarrhine and platyrrhine primate herpesviruses, little is known about herpesviruses in prosimians. We aimed to identify and characterize herpesviruses in prosimians with proliferative lymphocytic disease. DNA was extracted from tissues of 9 gray mouse lemurs (Microcebus murinus) and 3 pygmy slow lorises (Nycticebus pygmaeus) with lymphoproliferative lesions, and we performed nested PCR and sequencing for detection of herpesviruses and polyomaviruses. We identified 3 novel herpesviruses and performed phylogenetic analyses to characterize their relationship with other herpesviruses. A gray mouse lemur herpesvirus clustered with other primate herpesviruses within the subfamily Betaherpesvirinae, just basal to the genus Cytomegalovirus. The other gray mouse lemur herpesvirus and the pygmy slow loris herpesvirus clustered within the subfamily Gammaherpesvirinae, although the relationships within the subfamily were less resolved. Quantitative PCR assays were developed for the 2 new gray mouse lemur viruses, providing specific, faster, less expensive, and quantitative detection tools. Further studies are needed to elucidate the relationship between the presence of these viruses and the severity or presence of lymphoproliferative lesions in prosimians.


Assuntos
Cheirogaleidae , Herpesviridae , Strepsirhini , Animais , Filogenia , Herpesviridae/genética
5.
EBioMedicine ; 91: 104551, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37055258

RESUMO

BACKGROUND: High myopia (HM), defined as a spherical equivalent refractive error (SER) ≤ -6.00 diopters (D), is a leading cause of sight impairment, through myopic macular degeneration (MMD). We aimed to derive an improved polygenic score (PGS) for predicting children at risk of HM and to test if a PGS is predictive of MMD after accounting for SER. METHODS: The PGS was derived from genome-wide association studies in participants of UK Biobank, CREAM Consortium, and Genetic Epidemiology Research on Adult Health and Aging. MMD severity was quantified by a deep learning algorithm. Prediction of HM was quantified as the area under the receiver operating curve (AUROC). Prediction of severe MMD was assessed by logistic regression. FINDINGS: In independent samples of European, African, South Asian and East Asian ancestry, the PGS explained 19% (95% confidence interval 17-21%), 2% (1-3%), 8% (7-10%) and 6% (3-9%) of the variation in SER, respectively. The AUROC for HM in these samples was 0.78 (0.75-0.81), 0.58 (0.53-0.64), 0.71 (0.69-0.74) and 0.67 (0.62-0.72), respectively. The PGS was not associated with the risk of MMD after accounting for SER: OR = 1.07 (0.92-1.24). INTERPRETATION: Performance of the PGS approached the level required for clinical utility in Europeans but not in other ancestries. A PGS for refractive error was not predictive of MMD risk once SER was accounted for. FUNDING: Supported by the Welsh Government and Fight for Sight (24WG201).


Assuntos
Degeneração Macular , Miopia , Adulto , Criança , Humanos , Povo Asiático/genética , Etnicidade , Estudo de Associação Genômica Ampla , Degeneração Macular/diagnóstico , Degeneração Macular/genética , Degeneração Macular/epidemiologia , Miopia/diagnóstico , Miopia/genética , População Europeia , População Africana , População do Sul da Ásia , População do Leste Asiático
6.
Dev Med Child Neurol ; 65(2): 223-231, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35735110

RESUMO

AIM: We examined children 10 to 11 years after grade 3 or 4 intraventricular haemorrhage and ventricular dilation (IVHVD) and investigated whether the grade of IVHVD affected their visual outcome. We explored associations between visual outcomes with cognitive outcomes and extra support at school. METHOD: The visual examinations were part of a 10-year follow-up study for children in a randomized trial. Testers followed a protocol and were masked to whether the child had experienced grade 3 or grade 4 IVHVD and all other data. RESULTS: Thirty-two children were tested: 24 were male and mean (standard deviation) age was 10 years 5 months (1 year 2 months); range 8 years 9 months to 12 years 9 months. All had at least one visual impairment. The median (interquartile range) number of impairments per child was six (six to nine) for children who experienced a grade 4 IVHVD compared with three (two to four) for children who experienced a grade 3 IVHVD (p = 0.003). Each extra vision impairment per child was associated with increased educational support at school, after adjustment for developmental age equivalence (odds ratio = 1.7 [95% confidence interval 1.1-2.6], p = 0.015). INTERPRETATION: Children who experience grade 3 or 4 IVHVD have a high level of visual morbidity at age 10 to 11 years. These children may have unmet visual needs and their outcomes might improve if these needs could be addressed. WHAT THIS PAPER ADDS: Parent-reported questionnaire responses underestimated directly assessed visual morbidity. Grade 4 intraventricular haemorrhage and ventricular dilatation (IVHVD) was followed by more vision impairments than grade 3 IVHVD. Simple tests of visual perceptual skills correlated with the neuropsychology tests. Children with supranuclear eye movement disorders were more likely to be receiving extra help at school. Each additional visual impairment increased the likelihood of extra educational support.


Assuntos
Hemorragia Cerebral , Transtornos da Visão , Criança , Feminino , Humanos , Masculino , Dilatação , Seguimentos , Estudos Prospectivos , Transtornos da Visão/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Eye (Lond) ; 37(10): 1958-1965, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36258009

RESUMO

Cerebral Visual Impairment (CVI) is a common condition in the UK. Patients with conditions associated with CVI are frequently seen in paediatric ophthalmology clinics offering eye care professionals an opportunity to identify children proactively. In most cases CVI occurs as part of a neurodevelopmental condition or as a feature of multiple and complex disabilities. However, CVI can also be seen in children with apparently typical development. In some cases, high contrast visual acuity is normal and in other cases severely impaired. As such, identification of CVI requires evaluation of aspects of visual performance beyond high contrast acuity and consideration that visual function of those with CVI may fluctuate. Few paediatric ophthalmologists have received formal training in CVI. The detection and diagnosis of CVI varies across the UK and patients report hugely different experiences. A diagnosis of CVI is made based on professional clinical judgement and it is recognised that individual perspectives and local practice in the specific methodologies of assessment will vary. A systematic review and survey of professionals is underway to attempt to reach agreement on diagnostic criteria. Nonetheless, established pathways and published protocols can offer guidance on how a paediatric ophthalmology service can approach assessment of the child with suspected CVI. The purpose of this paper is to present a summary of research and clinical practice methods for detecting and diagnosing CVI in a paediatric ophthalmology outpatient setting. It represents current understanding of the topic and acknowledges the evolving nature of both practice and the evidence-base. A rapid literature review was undertaken to identify articles relating to clinical investigation of children with CVI. A focus group of QTVI and subject matter experts from sight loss charities was undertaken to address areas which were not covered by the literature review.


Assuntos
Oftalmologia , Transtornos da Visão , Criança , Humanos , Consenso , Transtornos da Visão/diagnóstico , Transtornos da Visão/terapia , Acuidade Visual , Cegueira
8.
PLoS Genet ; 18(11): e1010478, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36395078

RESUMO

Myopia most often develops during school age, with the highest incidence in countries with intensive education systems. Interactions between genetic variants and educational exposure are hypothesized to confer susceptibility to myopia, but few such interactions have been identified. Here, we aimed to identify genetic variants that interact with education level to confer susceptibility to myopia. Two groups of unrelated participants of European ancestry from UK Biobank were studied. A 'Stage-I' sample of 88,334 participants whose refractive error (avMSE) was measured by autorefraction and a 'Stage-II' sample of 252,838 participants who self-reported their age-of-onset of spectacle wear (AOSW) but who did not undergo autorefraction. Genetic variants were prioritized via a 2-step screening process in the Stage-I sample: Step 1 was a genome-wide association study for avMSE; Step 2 was a variance heterogeneity analysis for avMSE. Genotype-by-education interaction tests were performed in the Stage-II sample, with University education coded as a binary exposure. On average, participants were 58 years-old and left full-time education when they were 18 years-old; 35% reported University level education. The 2-step screening strategy in the Stage-I sample prioritized 25 genetic variants (GWAS P < 1e-04; variance heterogeneity P < 5e-05). In the Stage-II sample, 19 of the 25 (76%) genetic variants demonstrated evidence of variance heterogeneity, suggesting the majority were true positives. Five genetic variants located near GJD2, RBFOX1, LAMA2, KCNQ5 and LRRC4C had evidence of a genotype-by-education interaction in the Stage-II sample (P < 0.002) and consistent evidence of a genotype-by-education interaction in the Stage-I sample. For all 5 variants, University-level education was associated with an increased effect of the risk allele. In this cohort, additional years of education were associated with an enhanced effect of genetic variants that have roles including axon guidance and the development of neuronal synapses and neural circuits.


Assuntos
Miopia , Erros de Refração , Humanos , Pessoa de Meia-Idade , Adolescente , Estudo de Associação Genômica Ampla , Miopia/genética , Escolaridade , Erros de Refração/genética , Alelos , Fatores de Processamento de RNA/genética
9.
BMJ Open ; 12(9): e059946, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36130761

RESUMO

INTRODUCTION: Hypoaccommodation is common in children born prematurely and those with hypoxic ischaemic encephalopathy (HIE), with the potential to affect wider learning. These children are also at risk of longer-term cerebral visual impairment. It is also well recognised that early intervention for childhood visual pathology is essential, because neuroplasticity progressively diminishes during early life. This study aims to establish the feasibility and acceptability of conducting a randomised controlled trial to test the effectiveness of early near vision correction with spectacles in infancy, for babies, at risk of visual dysfunction. METHODS AND ANALYSIS: This is a parallel group, open-label, randomised controlled (feasibility) study to assess visual outcomes in children with perinatal brain injury when prescribed near vision spectacles compared with the current standard care-waiting until a problem is detected. The study hypothesis is that accommodation, and possibly other aspects of vision, may be improved by intervening earlier with near vision glasses. Eligible infants (n=75, with either HIE or <29 weeks preterm) will be recruited and randomised to one of three arms, group A (no spectacles) and two intervention groups: B1 or B2. Infants in both intervention groups will be offered glasses with +3.00 DS added to the full cycloplegic refraction and prescribed for full time wear. Group B1 will get their first visit assessment and intervention at 8 weeks corrected gestational age (B1) and B2 at 16 weeks corrected gestational age. All infants will receive a complete visual and neurodevelopmental assessment at baseline and a follow-up visit at 3 and 6 months after the first visit. ETHICS AND DISSEMINATION: The South-Central Oxford C Research Ethics Committee has approved the study. Members of the PPI committee will give advice on dissemination of results through peer-reviewed publications, conferences and societies. TRIAL REGISTRATION NUMBER: ISRCTN14646770, NCT05048550, NIHR ref: PB-PG-0418-20006.


Assuntos
Encefalopatias , Midriáticos , Encefalopatias/complicações , Criança , Intervenção Educacional Precoce , Óculos/efeitos adversos , Estudos de Viabilidade , Humanos , Lactente , Recém-Nascido , Ensaios Clínicos Controlados Aleatórios como Assunto , Transtornos da Visão/etiologia , Transtornos da Visão/terapia
10.
Bone Marrow Transplant ; 57(10): 1507-1513, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35768571

RESUMO

The Myeloma X trial provided a platform to explore genetics in relation to systematic assessment of patient-reported outcomes at key points during salvage treatment in multiple myeloma (MM) patients. Blood DNA was obtained in 191 subjects for single nucleotide polymorphism (SNP) genotyping. By univariable analysis, the non-coding rs2562456 SNP, upstream of LINC00664, was associated with several relevant pain and health-related quality-of-life (HRQoL) scores at 100 days after allocation to consolidation with autologous stem cell transplantation or weekly cyclophosphamide. Presence of the minor (C) allele was associated with lower pain interference (p = 0.014) and HRQoL pain (p = 0.003), and higher HRQoL global health status (p = 0.011) and physical functioning (p = 0.007). These effects were not modified by treatment arm and were no longer significant at 6 months. Following induction therapy, the rs13361160 SNP near the CCT5 and FAM173B genes was associated with higher global health (p = 0.027) and physical functioning (p = 0.013). This exploratory study supports associations between subjective parameters in MM with SNPs previously identified in genome-wide association studies of pain. Conversely, SNPs in candidate genes involved in opioid and transporter pathways showed no effect. Further studies are warranted in well-defined cancer populations, and potentially assisted by whole genome sequencing with germline analysis in routine diagnostics in haematological cancers.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Analgésicos Opioides , Ciclofosfamida , DNA , Estudo de Associação Genômica Ampla , Humanos , Mieloma Múltiplo/genética , Mieloma Múltiplo/terapia , Recidiva Local de Neoplasia , Dor , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Transplante Autólogo , Reino Unido
11.
Eur J Hum Genet ; 30(11): 1226-1232, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35618892

RESUMO

Parents pass on both their genes and environment to offspring, prompting debate about the relative importance of nature versus nurture in the inheritance of complex traits. Advances in molecular genetics now make it possible to quantify an individual's genetic predisposition to a trait via his or her 'polygenic score'. However, part of the risk captured by an individual's polygenic score may actually be attributed to the genotype of their parents. In the most well-studied example of this indirect 'genetic nurture' effect, about half the genetic contribution to educational attainment was found to be attributed to parental alleles, even if those alleles were not inherited by the child. Refractive errors, such as myopia, are a common cause of visual impairment and pose high economic and quality-of-life costs. Despite strong evidence that refractive errors are highly heritable, the extent to which genetic risk is conferred directly via transmitted risk alleles or indirectly via the environment that parents create for their children is entirely unknown. Here, an instrumental variable analysis in 1944 pairs of adult siblings from the United Kingdom was used to quantify the proportion of the genetic risk ('single nucleotide polymorphism (SNP) heritability') of refractive error contributed by genetic nurture. We found no evidence of a contribution from genetic nurture: non-within-family SNP-heritability estimate = 0.213 (95% confidence interval 0.134-0.310) and within-family SNP-heritability estimate = 0.250 (0.152-0.372). Our findings imply the genetic contribution to refractive error is principally an intrinsic effect from alleles transmitted from parents to offspring.


Assuntos
Herança Multifatorial , Erros de Refração , Adulto , Criança , Humanos , Predisposição Genética para Doença , Genótipo , Polimorfismo de Nucleotídeo Único , Erros de Refração/genética
12.
Hum Mol Genet ; 31(11): 1909-1919, 2022 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-35022715

RESUMO

Refractive errors are associated with a range of pathological conditions, such as myopic maculopathy and glaucoma, and are highly heritable. Studies of missense and putative loss of function (pLOF) variants identified via whole exome sequencing (WES) offer the prospect of directly implicating potentially causative disease genes. We performed a genome-wide association study for refractive error in 51 624 unrelated adults, of European ancestry, aged 40-69 years from the UK and genotyped using WES. After testing 29 179 pLOF and 495 263 missense variants, 1 pLOF and 18 missense variants in 14 distinct genomic regions were taken forward for fine-mapping analysis. This yielded 19 putative causal variants of which 18 had a posterior inclusion probability >0.5. Of the 19 putative causal variants, 12 were novel discoveries. Specific variants were associated with a more myopic refractive error, while others were associated with a more hyperopic refractive error. Association with age of onset of spectacle wear (AOSW) was examined in an independent validation sample (38 100 early AOSW cases and 74 243 controls). Of 11 novel variants that could be tested, 8 (73%) showed evidence of association with AOSW status. This work identified COL4A4 and ATM as novel candidate genes associated with refractive error. In addition, novel putative causal variants were identified in the genes RASGEF1, ARMS2, BMP4, SIX6, GSDMA, GNGT2, ZNF652 and CRX. Despite these successes, the study also highlighted the limitations of community-based WES studies compared with high myopia case-control WES studies.


Assuntos
Miopia , Erros de Refração , Adulto , Exoma/genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Miopia/genética , Proteínas de Neoplasias/genética , Proteínas Citotóxicas Formadoras de Poros , Erros de Refração/genética , Sequenciamento do Exoma
13.
J AAPOS ; 26(1): 12.e1-12.e6, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34856371

RESUMO

PURPOSE: To replicate associations between polymorphisms in the WRB and TSPAN10 genes and strabismus in an independent Finnish cohort and to calculate their population attributable risk. METHODS: Polymorphisms in the WRB (rs2244352) and TSPAN10 (rs6420484) genes were investigated in individuals from the FinnGen study group who had one of three categories of strabismus, with clinical diagnoses of (1) "strabismus-all subtypes" (3,515 cases and 173,384 controls), (2) "convergent concomitant strabismus" (ICD-10 code H50.0; 737 cases and 170,976 controls), and (3) "divergent concomitant strabismus" (ICD-10 code H50.1; 1,059 cases and 170,976 controls). RESULTS: The WRB polymorphism was associated with "all subtypes" of strabismus (OR = 1.08; P = 0.008) and divergent strabismus (OR = 1.11; P = 0.046) but not with convergent strabismus (P = 0.41). The WRB polymorphism had a population attributable risk of 3.4% for all strabismus subtypes and 4.7% for divergent strabismus. The TSPAN10 polymorphism was associated with all three strabismus phenotypes: "all subtypes" (OR = 1.08; P = 0.002), convergent strabismus (OR = 1.19; P = 0.001) and divergent strabismus (OR = 1.20; P =7.21E-05). The population attributable risk for the TSPAN10 polymorphism was 6.0% for any strabismus, 13.3% for convergent strabismus, and 13.9% for divergent strabismus. CONCLUSIONS: Genetic association with strabismus was replicated in a Finnish cohort for two common polymorphisms. Under the assumption that these polymorphisms are independent of other risk factors, they are responsible for up to 20% of isolated cases of strabismus in Finland, similar to estimates in other European populations.


Assuntos
Esotropia , Exotropia , Estrabismo , Finlândia/epidemiologia , Humanos , Polimorfismo Genético , Estrabismo/genética
14.
Transl Vis Sci Technol ; 10(12): 34, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34709397

RESUMO

Purpose: Hyperopia (farsightedness) has been associated with a deficit in children's educational attainment in some studies. We aimed to investigate the causality of the relationship between refractive error and educational attainment. Methods: Mendelian randomization (MR) analysis in 74,463 UK Biobank participants was used to estimate the causal effect of refractive error on years spent in full-time education, which was taken as a measure of educational attainment. A polygenic score for refractive error derived from 129 genetic variants was used as the instrumental variable. Both linear and nonlinear (allowing for a nonlinear relationship between refractive error and educational attainment) MR analyses were performed. Results: Assuming a linear relationship between refractive error and educational attainment, the causal effect of refractive error on years spent in full-time education was estimated as -0.01 yr/D (95% confidence interval, -0.04 to +0.02; P = 0.52), suggesting minimal evidence for a non-zero causal effect. Nonlinear MR supported the hypothesis of the nonlinearity of the relationship (I2 = 80.3%; Cochran's Q = 28.2; P = 8.8e-05) but did not suggest that hyperopia was associated with a major deficit in years spent in education. Conclusions: This work suggested that the causal relationship between refractive error and educational attainment was nonlinear but found no evidence that moderate hyperopia caused a major deficit in educational attainment. Importantly, however, because statistical power was limited and some participants with moderate hyperopia would have worn spectacles as children, modest adverse effects may have gone undetected. Translational Relevance: These findings suggest that moderate hyperopia does not cause a major deficit in educational attainment.


Assuntos
Hiperopia , Erros de Refração , Criança , Escolaridade , Óculos , Humanos , Hiperopia/epidemiologia , Hiperopia/genética , Análise da Randomização Mendeliana
15.
Invest Ophthalmol Vis Sci ; 62(13): 24, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34698770

RESUMO

Purpose: Emmetropization requires coordinated scaling of the major ocular components, corneal curvature and axial length. This coordination is achieved in part through a shared set of genetic variants that regulate eye size. Poorly coordinated scaling of corneal curvature and axial length results in refractive error. We tested the hypothesis that genetic variants regulating eye size in emmetropic eyes are distinct from those conferring susceptibility to refractive error. Methods: A genome-wide association study (GWAS) for corneal curvature in 22,180 adult emmetropic individuals was performed as a proxy for a GWAS for eye size. A polygenic score created using lead GWAS variants was tested for association with corneal curvature and axial length in an independent sample: 437 classified as emmetropic and 637 as ametropic. The genetic correlation between eye size and refractive error was calculated using linkage disequilibrium score regression for approximately 1 million genetic variants. Results: The GWAS for corneal curvature in emmetropes identified 32 independent genetic variants (P < 5.0e-08). A polygenic score created using these 32 genetic markers explained 3.5% (P < 0.001) and 2.0% (P = 0.001) of the variance in corneal curvature and axial length, respectively, in the independent sample of emmetropic individuals but was not predictive of these traits in ametropic individuals. The genetic correlation between eye size and refractive error was close to zero (rg = 0.00; SE = 0.06; P = 0.95). Conclusions: These results support the hypothesis that genetic variants regulating eye size in emmetropic eyes do not overlap with those conferring susceptibility to myopia. This suggests that distinct biological pathways regulate normal eye growth and myopia development.


Assuntos
Comprimento Axial do Olho/diagnóstico por imagem , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/métodos , Miopia/genética , Polimorfismo de Nucleotídeo Único , Refração Ocular/fisiologia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Miopia/diagnóstico , Miopia/fisiopatologia , Adulto Jovem
16.
BMJ Open ; 11(9): e051014, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34588256

RESUMO

OBJECTIVES: Cerebral visual impairment (CVI) comprises a heterogeneous group of brain-related vision problems. A core outcome set (COS) represents the most important condition-specific outcomes according to patients, carers, professionals and researchers. We aimed to produce a COS for studies evaluating interventions for children with CVI, to increase the relevance of research for families and professionals and thereby to improve outcomes for affected children. DESIGN: We used methods recommended by the Core Outcome Measures in Effectiveness Trials Initiative. These included a proportionate literature review of outcomes used in previous studies; qualitative interviews with children and families; a two-round Delphi survey involving parents, children and professionals and a consensus meeting to ratify the most important outcomes. SETTING: Telephone interviews and online Delphi surveys of participants who all lived in UK or Eire. PARTICIPANTS: Eighteen parents and six young people were interviewed. Delphi participants (n=80 did both rounds) included professionals working with children who have CVI (teachers, orthoptists, ophthalmologists, optometrists, qualified teachers for visually impaired, family members (parents and siblings) and affected children. RESULTS: The literature review included 13 studies yielding 37 outcomes. Qualitative interviews provided 22 outcomes. After combining and refining similar items, the first round contained 23 outcomes and the second 46. At the consensus meeting, 5 attendees recommended 27 outcomes for inclusion in the CVI COS, of which 15 were ratified as most important, including 4 related to vision; 1 to family well-being; 1 to adults around the child being informed about CVI and the rest to the child's abilities to engage with people and surroundings. CONCLUSIONS: Good engagement from participants led to the development of a COS. Future research will be useful to identify the best ways to measure COS items and potentially to update this COS as more interventions for CVI are developed. TRIAL REGISTRATION NUMBER: ISRCTN13762177.


Assuntos
Avaliação de Resultados em Cuidados de Saúde , Transtornos da Visão , Adolescente , Adulto , Criança , Consenso , Técnica Delphi , Humanos , Irlanda , Projetos de Pesquisa , Resultado do Tratamento , Reino Unido , Transtornos da Visão/terapia
17.
Front Hum Neurosci ; 15: 689683, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34305554

RESUMO

Cerebral Visual Impairment (CVI) is an umbrella term which includes abnormalities in visual acuity, or contrast sensitivity or colour; ocular motility; visual field and the conscious and unconscious filtering or processing of visual input. Children with CVI have specific needs and problems relating to their development from infancy to adulthood which can impact on their wellbeing. Recent research indicates the complexities of living with CVI but there remains limited information of the full impact of CVI on families' everyday lives. The qualitative interviews reported here explored families' experiences to discover the impact of CVI on all aspects of everyday life. Parents and children (aged 6-18) were invited to participate in semi-structured interviews, either face to face, by phone or video call between January 2018 and February 2019. Topics covered everyday practicalities of living with CVI, focusing on challenges and what worked well at school and home. Interviews were audio-recorded and subject to thematic analysis to look for patterns across the data. Twenty families took part in interviews, with eight children/young people within those families contributing interviews of their own. Four themes were developed from the interviews: (1) Assessment and understanding implications of CVI, (2) Education, (3) Family life, (4) Psychological wellbeing and quality of life. The interviews provide valuable insights into the impact of living with CVI and highlight the need for more awareness of the condition among professionals in both health and education settings.

18.
BMJ Open ; 11(5): e044830, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33952548

RESUMO

INTRODUCTION: Cerebral visual impairment (CVI) refers to a spectrum of brain-related vision problems. CVI is associated with poor educational and mental health outcomes. An intervention has been developed to help children with CVI, involving input from clinicians, teachers and parents. The effectiveness of this intervention needs to be evaluated. This study aims to guide any refinements to the intervention or the design of a future cluster-randomised trial that may be needed. METHODS AND ANALYSIS: This study will include all methods anticipated for a future cluster-randomised controlled trial. Eight primary schools will be recruited and randomised to receive the intervention or carry on with usual practice. The intervention will comprise an information pack for schools and access to a local paediatric ophthalmology clinic (who are prepared to assess them for CVI), for up to 5% of participating children. Outcome assessments will be carried out at baseline (before randomisation) and after 4-5 months of intervention period. Assessments will include children's self-reported quality of life, their learning ability and behaviour as reported by teachers, and family functioning reported by parents. Cost data will include service use, family expenditure on additional support (eg, private appointments and administration) and school spending and resource used in helping children with special educational needs or disability. A process evaluation (PE) will collect additional data relating to the implementation of the intervention and the trial processes, in the school and clinic settings. The protocol for the PE will be reported separately. ETHICS AND DISSEMINATION: Ethical permission was obtained from the University of Bristol Faculty of Health Sciences Ethical Committee. The results will inform the design of a future trial to assess the effectiveness and cost-effectiveness of the intervention and will be shared with participants, CVI-support groups and peer-viewed journals. TRIAL REGISTRATION NUMBER: ISRCTN13762177; Pre-results.


Assuntos
Qualidade de Vida , Instituições Acadêmicas , Criança , Análise Custo-Benefício , Estudos de Viabilidade , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Transtornos da Visão/prevenção & controle
19.
BMJ Open ; 11(5): e044856, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33952549

RESUMO

INTRODUCTION: Brain-related visual impairments, also known as cerebral visual impairment (CVI), are related to damage or poor function in the vision-related areas of the brain. There is broad agreement that CVI is an appropriate term to describe visual impairments that are not accounted by disorders of the eye or optic nerve, but differences remain as to which impairments can be included in this term. The CVI project is a programme of work that includes the development of a complex intervention to share knowledge with teachers, so that they can make both targeted and universal changes to support children with CVI. A feasibility study for a cluster-randomised controlled trial to evaluate this intervention is underway. This paper describes the protocol for an accompanying process evaluation to explore how the intervention is implemented and provide context for the interpretation of the feasibility trial outcomes. METHODS AND ANALYSIS: A logic model has been developed to guide data collection. Both qualitative and quantitative data will be collected to assess the feasibility and acceptability of the intervention, the study design and explore how any changes that occur are brought about. Interviews with key primary school staff and parents will investigate responses to the intervention and trial processes. Surveys will collect data on intervention implementation and knowledge of CVI. Photographs of classroom walls will document any changes to visual clutter and document analysis will look for changes to school special educational needs and disability (SEND) policies. ETHICS AND DISSEMINATION: Ethical approval was granted by the University of Bristol Faculty of Health Sciences Ethics Committee. Findings will contribute to the development of a full-scale cluster-randomised controlled trial to assess the effectiveness of the intervention with adequate statistical power. The results will also support the refinement of the intervention and its underlying theory.


Assuntos
Pais , Instituições Acadêmicas , Criança , Docentes , Estudos de Viabilidade , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Transtornos da Visão/prevenção & controle
20.
JAMA Ophthalmol ; 139(6): 601-609, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33830181

RESUMO

IMPORTANCE: Uncertainty currently exists about whether the same genetic variants are associated with susceptibility to low myopia (LM) and high myopia (HM) and to myopia and hyperopia. Addressing this question is fundamental to understanding the genetics of refractive error and has clinical relevance for genotype-based prediction of children at risk for HM and for identification of new therapeutic targets. OBJECTIVE: To assess whether a common set of genetic variants are associated with susceptibility to HM, LM, and hyperopia. DESIGN, SETTING, AND PARTICIPANTS: This genetic association study assessed unrelated UK Biobank participants 40 to 69 years of age of European and Asian ancestry. Participants 40 to 69 years of age living in the United Kingdom were recruited from January 1, 2006, to October 31, 2010. Of the total sample of 502 682 participants, 117 279 (23.3%) underwent an ophthalmic assessment. Data analysis was performed from December 12, 2019, to June 23, 2020. EXPOSURES: Four refractive error groups were defined: HM, -6.00 diopters (D) or less; LM, -3.00 to -1.00 D; hyperopia, +2.00 D or greater; and emmetropia, 0.00 to +1.00 D. Four genome-wide association study (GWAS) analyses were performed in participants of European ancestry: (1) HM vs emmetropia, (2) LM vs emmetropia, (3) hyperopia vs emmetropia, and (4) LM vs hyperopia. Polygenic risk scores were generated from GWAS summary statistics, yielding 4 sets of polygenic risk scores. Performance was assessed in independent replication samples of European and Asian ancestry. MAIN OUTCOMES AND MEASURES: Odds ratios (ORs) of polygenic risk scores in replication samples. RESULTS: A total of 51 841 unrelated individuals of European ancestry and 2165 unrelated individuals of Asian ancestry were assigned to a specific refractive error group and included in our analyses. Polygenic risk scores derived from all 4 GWAS analyses were predictive of all categories of refractive error in both European and Asian replication samples. For example, the polygenic risk score derived from the HM vs emmetropia GWAS was predictive in the European sample of HM vs emmetropia (OR, 1.58; 95% CI, 1.41-1.77; P = 1.54 × 10-15) as well as LM vs emmetropia (OR, 1.15; 95% CI, 1.07-1.23; P = 8.14 × 10-5), hyperopia vs emmetropia (OR, 0.83; 95% CI, 0.77-0.89; P = 4.18 × 10-7), and LM vs hyperopia (OR, 1.45; 95% CI, 1.33-1.59; P = 1.43 × 10-16). CONCLUSIONS AND RELEVANCE: Genetic risk variants were shared across HM, LM, and hyperopia and across European and Asian samples. Individuals with HM inherited a higher number of variants from among the same set of myopia-predisposing alleles and not different risk alleles compared with individuals with LM. These findings suggest that treatment interventions targeting common genetic risk variants associated with refractive error could be effective against both LM and HM.


Assuntos
Hiperopia , Miopia , Erros de Refração , Criança , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Hiperopia/genética , Miopia/genética
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