PRECIS: In a cohort study of 120,307 participants with 25+ years of follow-up, a history of nonmelanoma skin cancer (NMSC) was associated with a 40% higher exfoliation glaucoma (XFG) risk. PURPOSE: The purpose of this study was to evaluate the relationship between NMSC (a marker of ultraviolet radiation exposure) and XFG. METHODS: We performed a cohort study of US women (n=79,102; 1980-2014) and men (n=41,205; 1986-2014), aged 40+ years and at risk for glaucoma who reported eye examinations. From 1984 (women)/1988 (men), we asked about basal cell carcinoma or squamous cell carcinoma history separately; in prior years, we asked about any NMSC history in a single question. Squamous cell carcinoma was confirmed with histopathology reports while basal cell carcinoma and any early (<1984/<1988) NMSC history was self-reported. Incident XFG cases (362 women and 83 men) were confirmed with medical records. Using pooled data, we estimated multivariable-adjusted relative risks [MVRRs; 95% confidence intervals (CIs)] with Cox proportional hazards models that were stratified by age (in mo), 2-year time period at risk and average lifetime residential latitude. RESULTS: In multivariable-adjusted analyses, we observed a 40% higher XFG risk with any NMSC history (MVRR=1.40; 95% CI=1.08-1.82); the association was observed even with 4 and 8-year lags in NMSC history. Also, the NMSC association was stronger in younger (below 65 y; MVRR=2.56; 95% CI=1.62-4.05) versus older participants (65 y and above; MVRR=1.25; 95% CI=0.94-1.66; P for interaction=0.01) and those living in the northern latitudes (≥42°N; MVRR=1.92; 95% CI=1.28-2.88) versus more southern latitudes (<42°N; MVRR=1.19; 95% CI=0.86-1.66; P for interaction=0.04). CONCLUSION: NMSC was associated with higher XFG risk, particularly among younger participants and those living in the Northern US.
PURPOSE: We explored whether risk factor associations differed by primary open-angle glaucoma (POAG) subtypes defined by visual field (VF) loss pattern (i.e., paracentral or peripheral). METHODS: We included 77,157 women in the Nurses Health Study and 42,773 men in the Health Professionals Follow-up Study (1986-2010) and incident medical-record confirmed cases of paracentral (n=440) and peripheral (n=865) POAG subtypes. We evaluated African-heritage, glaucoma family history, body mass index (BMI), mean arterial blood pressure, diabetes mellitus, physical activity, smoking, caffeine and alcohol intakes. We used competing risk Cox regression analyses modeling age as the metameter and stratified by age, cohort and event type. We sequentially identified factors with the least significant differences in associations with POAG subtypes ("stepwise down" approach with P for heterogeneity [P-het]<0.10 as threshold). RESULTS: BMI was more inversely associated with the POAG paracentral VF loss subtype than the peripheral VF loss subtype (per 10 kg/m2; hazard ratio [HR]=0.67 [95% Confidence Interval [CI]: 0.52, 0.86] vs. HR=0.93 [95% CI: 0.78, 1.10]; P-het=0.03) as was smoking (per 10 pack-years; HR=0.92 [95% CI: 0.87, 0.98] vs. HR=0.98 [95% CI: 0.94, 1.01]; P-het=0.09). These findings were robust in sensitivity analyses using a "stepwise up" approach (identify factors that showed the most significant differences). Non-heterogeneous (p-het>0.10) adverse associations with both POAG subtypes were observed with glaucoma family history, diabetes, African-heritage, greater caffeine intake and higher mean arterial pressure. CONCLUSIONS: These data indicate that POAG with early paracentral VF loss has distinct as well as common determinants compared to POAG with peripheral VF loss.
PURPOSE: To evaluate the relation between time spent outdoors at various life periods and risk of exfoliation glaucoma or exfoliation glaucoma suspect. DESIGN: Retrospective cohort study in the United States. METHODS: Participants (49 033 women in the Nurses Health Study and 20 066 men in the Health Professionals Follow-up Study) were 60+ years old, were free of glaucoma and cataract, reported eye examinations, and completed questions about time spent outdoors in direct sunlight at midday at 3 life periods: high school to age 24 years, age 25-35 years, and age 36-59 years (asked in 2006 in women and 2008 in men). Participants were followed biennially with mailed questionnaires from 1980 women/1986 men to 2010. Incident cases (223 women and 38 men) were confirmed with medical records. Cohort-specific multivariable-adjusted rate ratios from Cox proportional hazards models were estimated and pooled with meta-analysis. RESULTS: Although no association was observed with greater time spent outdoors in the ages of 25-35 or ages 36-59 years, the pooled multivariable-adjusted rate ratios for ≥11 hours per week spent outdoors in high school to age 24 years compared with ≤5 hours per week was 2.00 (95% confidence interval = 1.30, 3.08; P for linear trend = .001). In women, this association was stronger in those who resided in the southern geographic tier in young adulthood (P for interaction = .07). CONCLUSIONS: Greater time spent outdoors in young adulthood was associated with risk of exfoliation glaucoma or exfoliation glaucoma suspect, supporting an etiologic role of early exposures to climatic factors.
PRECIS: In a cohort study of 120,307 participants with 25+ years of follow-up, a history of non-melanoma skin cancer was associated with a 40% higher exfoliation glaucoma risk. PURPOSE: To evaluate the relationship between non-melanoma skin cancer (a marker of ultraviolet radiation exposure) and exfoliation glaucoma (XFG). METHODS: We performed a cohort study of US women (n=79,102; 1980-2014) and men (n=41,205; 1986-2014), aged 40+ years and at risk for glaucoma who reported eye exams. From 1984 (women)/1988 (men), we asked about basal cell carcinoma (BCC) or squamous cell carcinoma (SCC) history separately; in prior years, we asked about any non-melanoma skin cancer history in a single question. SCC was confirmed with histopathology reports while BCC and any early (<1984/<1988) non-melanoma skin cancer history was self-reported. Incident XFG cases (362 women and 83 men) were confirmed with medical records. Using pooled data, we estimated multivariable-adjusted relative risks (MVRR; 95% confidence intervals [CIs]) with Cox proportional hazards models that were stratified by age (in months), 2-year time period at risk and average lifetime residential latitude. RESULTS: In multivariable-adjusted analyses, we observed a 40% higher XFG risk with any non-melanoma skin cancer history (MVRR=1.40; 95% CI=1.08,1.82); the association was observed even with 4 and 8 year lags in non-melanoma skin cancer history. Also, the non-melanoma skin cancer association was stronger in younger (<65▒y; MVRR=2.56; 95% CI=1.62,4.05) versus older participants (≥65▒y; MVRR=1.25; 95% CI=0.94,1.66; p for interaction=0.01) and those living in northern latitudes (≥42° north; MVRR=1.92; 95% CI=1.28,2.88) versus more southern latitudes (<42° north; MVRR=1.19; 95% CI=0.86,1.66; p for interaction=0.04). CONCLUSIONS: Non-melanoma skin cancer was associated with higher XFG risk, particularly among younger participants and those living in Northern US.
OBJECTIVES: To review the contribution of the Nurses' Health Study (NHS) to understanding the genetic and lifestyle factors that influence the risk of cataract, age-related macular degeneration, and glaucoma. METHODS: We performed a narrative review of the publications of the NHS between 1976 and 2016. RESULTS: The NHS has helped to elucidate the roles of genetics, lifestyle factors (e.g., cigarette smoking associated with cataract extraction and age-related macular degeneration), medical conditions (e.g., diabetes associated with cataract extraction and glaucoma), and dietary factors (e.g., greater carotenoid intake and lower glycemic diet associated with lower risk of age-related macular degeneration) in the etiology of degree and progression of lens opacities, cataract extraction, age-related macular degeneration, primary open-angle glaucoma, and exfoliation glaucoma. CONCLUSIONS: The findings from the NHS, combined with those of other studies, have provided compelling evidence to support public health recommendations for helping to prevent age-related eye diseases: abstinence from cigarette smoking, maintenance of healthy weight and diabetes prevention, and a healthy diet rich in fruits and vegetables.
Kang JH, Loomis SJ, Yaspan BL, Bailey JC, Weinreb RN, Lee RK, Lichter PR, Budenz DL, Liu Y, Realini T, Gaasterland D, Gaasterland T, Friedman DS, McCarty CA, Moroi SE, Olson L, Schuman JS, Singh K, Vollrath D, Wollstein G, Zack DJ, Brilliant M, Sit AJ, Christen WG, Fingert J, Forman JP, Buys ES, Kraft P, Zhang K, Allingham RR, Pericak-Vance MA, Richards JE, Hauser MA, Haines JL, Wiggs JL, Pasquale LR. Vascular tone pathway polymorphisms in relation to primary open-angle glaucoma. Eye (Lond) 2014;28(6):662-71.Abstract
AIMS: Vascular perfusion may be impaired in primary open-angle glaucoma (POAG); thus, we evaluated a panel of markers in vascular tone-regulating genes in relation to POAG. METHODS: We used Illumina 660W-Quad array genotype data and pooled P-values from 3108 POAG cases and 3430 controls from the combined National Eye Institute Glaucoma Human Genetics Collaboration consortium and Glaucoma Genes and Environment studies. Using information from previous literature and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, we compiled single-nucleotide polymorphisms (SNPs) in 186 vascular tone-regulating genes. We used the 'Pathway Analysis by Randomization Incorporating Structure' analysis software, which performed 1000 permutations to compare the overall pathway and selected genes with comparable randomly generated pathways and genes in their association with POAG. RESULTS: The vascular tone pathway was not associated with POAG overall or POAG subtypes, defined by the type of visual field loss (early paracentral loss (n=224 cases) or only peripheral loss (n=993 cases)) (permuted P≥0.20). In gene-based analyses, eight were associated with POAG overall at permuted P<0.001: PRKAA1, CAV1, ITPR3, EDNRB, GNB2, DNM2, HFE, and MYL9. Notably, six of these eight (the first six listed) code for factors involved in the endothelial nitric oxide synthase activity, and three of these six (CAV1, ITPR3, and EDNRB) were also associated with early paracentral loss at P<0.001, whereas none of the six genes reached P<0.001 for peripheral loss only. DISCUSSION: Although the assembled vascular tone SNP set was not associated with POAG, genes that code for local factors involved in setting vascular tone were associated with POAG.
PURPOSE: To evaluate long-term risk and outcomes of glaucoma in eyes with intermediate, posterior, and panuveitis managed with systemic or fluocinolone acetonide (0.59 mg, "implant") therapy. DESIGN: Prospective Follow-up of the Multicenter Uveitis Steroid Treatment (MUST) Clinical Trial Cohort. METHODS: Patients with intermediate, posterior, or panuveitis randomized to implant or systemic therapy (corticosteroid plus immunosuppression in >90%) were followed prospectively for glaucoma incidence and outcome. RESULTS: Among 405 uveitic at-risk eyes of 232 patients (median follow-up = 6.9 years), 40% (79/196) of eyes assigned and treated with implant and 8% (17/209) of eyes assigned and treated with systemic therapy (censoring eyes receiving an implant on implantation) developed glaucoma (hazard ratio [HR] = 5.9, 95% confidence interval [CI] 3.2, 10.8; P < .001). Adjustment for intraocular pressure (IOP) elevation during follow-up only partially mitigated the association of implant treatment with glaucoma incidence: HR = 3.1 (95% CI 1.6, 6.0); P = .001. Among 112 eyes of 83 patients developing glaucoma, the 5-year cumulative incidence following diagnosis of sustained (2 or more consecutive visits) worsening of mean deviation by ≥6 dB was 20% (95% CI 12%, 33%); 5-year cumulative incidence of sustained worsening of cup-to-disc ratio by ≥0.2 was 26% (95% CI 17%, 39%). CONCLUSIONS: The implant has substantially higher risk of glaucoma than systemic therapy, a difference not entirely explained by posttreatment IOP elevation. Management of IOP elevation was effective in preventing worsening of glaucoma for the large majority of cases, but even under expert clinical management, some glaucoma worsened. Uveitis cases should be monitored carefully for IOP elevation and glaucoma indefinitely.
Purpose: Recent studies indicate that mitochondrial proteins may contribute to the pathogenesis of primary open-angle glaucoma (POAG). In this study, we examined the association between POAG and common variations in gene-encoding mitochondrial proteins. Methods: We examined genetic data from 3430 POAG cases and 3108 controls derived from the combination of the GLAUGEN and NEIGHBOR studies. We constructed biological-system coherent mitochondrial nuclear-encoded protein gene-sets by intersecting the MitoCarta database with the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. We examined the mitochondrial gene-sets for association with POAG and with normal-tension glaucoma (NTG) and high-tension glaucoma (HTG) subsets using Pathway Analysis by Randomization Incorporating Structure. Results: We identified 22 KEGG pathways with significant mitochondrial protein-encoding gene enrichment, belonging to six general biological classes. Among the pathway classes, mitochondrial lipid metabolism was associated with POAG overall (P = 0.013) and with NTG (P = 0.0006), and mitochondrial carbohydrate metabolism was associated with NTG (P = 0.030). Examining the individual KEGG pathway mitochondrial gene-sets, fatty acid elongation and synthesis and degradation of ketone bodies, both lipid metabolism pathways, were significantly associated with POAG (P = 0.005 and P = 0.002, respectively) and NTG (P = 0.0004 and P < 0.0001, respectively). Butanoate metabolism, a carbohydrate metabolism pathway, was significantly associated with POAG (P = 0.004), NTG (P = 0.001), and HTG (P = 0.010). Conclusions: We present an effective approach for assessing the contributions of mitochondrial genetic variation to open-angle glaucoma. Our findings support a role for mitochondria in POAG pathogenesis and specifically point to lipid and carbohydrate metabolism pathways as being important.
Glaucoma is the leading cause of irreversible blindness globally . Despite its gravity, the disease is frequently undiagnosed in the community . Raised intraocular pressure (IOP) is the most important risk factor for primary open-angle glaucoma (POAG). Here we present a meta-analysis of 139,555 European participants, which identified 112 genomic loci associated with IOP, 68 of which are novel. These loci suggest a strong role for angiopoietin-receptor tyrosine kinase signaling, lipid metabolism, mitochondrial function and developmental processes underlying risk for elevated IOP. In addition, 48 of these loci were nominally associated with glaucoma in an independent cohort, 14 of which were significant at a Bonferroni-corrected threshold. Regression-based glaucoma-prediction models had an area under the receiver operating characteristic curve (AUROC) of 0.76 in US NEIGHBORHOOD study participants and 0.74 in independent glaucoma cases from the UK Biobank. Genetic-prediction models for POAG offer an opportunity to target screening and timely therapy to individuals most at risk.
PURPOSE: To determine the diagnostic capability of peripapillary 3-dimensional (3D) retinal nerve fiber layer (RNFL) volume measurements from spectral-domain optical coherence tomography (OCT) volume scans for open-angle glaucoma (OAG). DESIGN: Assessment of diagnostic accuracy. METHODS: Setting: Academic clinical setting. STUDY POPULATION: Total of 180 patients (113 OAG and 67 normal subjects). OBSERVATION PROCEDURES: One eye per subject was included. Peripapillary 3D RNFL volumes were calculated for global, quadrant, and sector regions, using 4 different-size annuli. Peripapillary 2D RNFL thickness circle scans were also obtained. MAIN OUTCOME MEASURES: Area under the receiver operating characteristic curve (AUROC) values, sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios. RESULTS: Among all 2D and 3D RNFL parameters, best diagnostic capability was associated with inferior quadrant 3D RNFL volume of the smallest annulus (AUROC value 0.977). Otherwise, global 3D RNFL volume AUROC values were comparable to global 2D RNFL thickness AUROC values for all 4 annulus sizes (P values: .0593 to .6866). When comparing the 4 annulus sizes for global RNFL volume, the smallest annulus had the best AUROC values (P values: .0317 to .0380). The smallest-size annulus may have the best diagnostic potential, partly owing to having no areas excluded for being larger than the 6 × 6 mm(2) scanned region. CONCLUSION: Peripapillary 3D RNFL volume showed excellent diagnostic performance for detecting glaucoma. Peripapillary 3D RNFL volume parameters have the same or better diagnostic capability compared to peripapillary 2D RNFL thickness measurements, although differences were not statistically significant.
PRECIS: Three-dimensional (3D) spectral domain optical coherence tomography (OCT) volume scans of the optic nerve head (ONH) and the peripapillary area are useful in the management of glaucoma in patients with a type I or II Boston Keratoprosthesis (KPro). PURPOSE: The purpose of this study was to report the use of spectral domain OCT in the management of glaucoma in patients with a type I or II Boston KPro. MATERIALS AND METHODS: This study is an observational case series. Four consecutive patients with KPro implants were referred for glaucoma evaluation. A comprehensive eye examination was performed which included disc photography, visual field testing, and high-density spectral domain OCT volume scans of the ONH and the peripapillary area. 2D and 3D parameters were calculated using custom-designed segmentation algorithms developed for glaucoma management. RESULTS: Spectral domain OCT parameters provided useful information in the diagnosis and management of 4 KPro patients. OCT parameters which can be used in KPro patients included 2D retinal nerve fiber layer (RNFL) thickness, 3D peripapillary RNFL volume, 3D peripapillary retinal thickness and volume, 3D cup volume, and 3D neuroretinal rim thickness and volume. In 3 of 4 cases where the traditional 2D RNFL thickness scan was limited by artifacts, 3D spectral domain OCT volume scans provided useful quantitative objective measurements of the ONH and peripapillary region. Therefore, 3D parameters derived from high-density volume scans as well as radial scans of the ONH can be used to overcome the limitations and artifacts associated with 2D RNFL thickness scans. CONCLUSIONS: Spectral domain OCT volume scans offer the possibility to enhance the evaluation of KPro patients with glaucoma by using both 2D and 3D diagnostic parameters that are easily obtained in a clinic setting.
PURPOSE: We examined the association of habitual caffeine intake with intraocular pressure (IOP) and glaucoma and whether genetic predisposition to higher IOP modified these associations. We also assessed whether genetic predisposition to higher coffee consumption was related to IOP. DESIGN: Cross-sectional study in the UK Biobank. PARTICIPANTS: We included 121 374 participants (baseline ages, 39-73 years) with data on coffee and tea intake (collected 2006-2010) and corneal-compensated IOP measurements in 2009. In a subset of 77 906 participants with up to 5 web-based 24-hour-recall food frequency questionnaires (2009-2012), we evaluated total caffeine intake. We also assessed the same relationships with glaucoma (9286 cases and 189 763 controls). METHODS: We evaluated multivariable-adjusted associations with IOP using linear regression and with glaucoma using logistic regression. For both outcomes, we examined gene-diet interactions using a polygenic risk score (PRS) that combined the effects of 111 genetic variants associated with IOP. We also performed Mendelian randomization using 8 genetic variants associated with coffee intake to assess potential causal effects of coffee consumption on IOP. MAIN OUTCOME MEASURES: Intraocular pressure and glaucoma. RESULTS: Mendelian randomization analysis did not support a causal effect of coffee drinking on IOP (P > 0.1). Greater caffeine intake was associated weakly with lower IOP: the highest (≥232 mg/day) versus lowest (<87 mg/day) caffeine consumption was associated with a 0.10-mmHg lower IOP (Ptrend = 0.01). However, the IOP PRS modified this association: among those in the highest IOP PRS quartile, consuming > 480 mg/day versus < 80 mg/day was associated with a 0.35-mmHg higher IOP (Pinteraction = 0.01). The relationship between caffeine intake and glaucoma was null (P ≥ 0.1). However, the IOP PRS also modified this relationship: compared with those in the lowest IOP PRS quartile consuming no caffeine, those in the highest IOP PRS quartile consuming ≥ 321 mg/day showed a 3.90-fold higher glaucoma prevalence (Pinteraction = 0.0003). CONCLUSIONS: Habitual caffeine consumption was associated weakly with lower IOP, and the association between caffeine consumption and glaucoma was null. However, among participants with the strongest genetic predisposition to elevated IOP, greater caffeine consumption was associated with higher IOP and higher glaucoma prevalence.
Central corneal thickness (CCT) is one of the most heritable ocular traits and it is also a phenotypic risk factor for primary open angle glaucoma (POAG). The present study uses the BXD Recombinant Inbred (RI) strains to identify novel quantitative trait loci (QTLs) modulating CCT in the mouse with the potential of identifying a molecular link between CCT and risk of developing POAG. The BXD RI strain set was used to define mammalian genomic loci modulating CCT, with a total of 818 corneas measured from 61 BXD RI strains (between 60-100 days of age). The mice were anesthetized and the eyes were positioned in front of the lens of the Phoenix Micron IV Image-Guided OCT system or the Bioptigen OCT system. CCT data for each strain was averaged and used to QTLs modulating this phenotype using the bioinformatics tools on GeneNetwork (www.genenetwork.org). The candidate genes and genomic loci identified in the mouse were then directly compared with the summary data from a human POAG genome wide association study (NEIGHBORHOOD) to determine if any genomic elements modulating mouse CCT are also risk factors for POAG.This analysis revealed one significant QTL on Chr 13 and a suggestive QTL on Chr 7. The significant locus on Chr 13 (13 to 19 Mb) was examined further to define candidate genes modulating this eye phenotype. For the Chr 13 QTL in the mouse, only one gene in the region (Pou6f2) contained nonsynonymous SNPs. Of these five nonsynonymous SNPs in Pou6f2, two resulted in changes in the amino acid proline which could result in altered secondary structure affecting protein function. The 7 Mb region under the mouse Chr 13 peak distributes over 2 chromosomes in the human: Chr 1 and Chr 7. These genomic loci were examined in the NEIGHBORHOOD database to determine if they are potential risk factors for human glaucoma identified using meta-data from human GWAS. The top 50 hits all resided within one gene (POU6F2), with the highest significance level of p = 10-6 for SNP rs76319873. POU6F2 is found in retinal ganglion cells and in corneal limbal stem cells. To test the effect of POU6F2 on CCT we examined the corneas of a Pou6f2-null mice and the corneas were thinner than those of wild-type littermates. In addition, these POU6F2 RGCs die early in the DBA/2J model of glaucoma than most RGCs. Using a mouse genetic reference panel, we identified a transcription factor, Pou6f2, that modulates CCT in the mouse. POU6F2 is also found in a subset of retinal ganglion cells and these RGCs are sensitive to injury.
PURPOSE: To report a case of bilateral acute angle-closure glaucoma associated with hyponatremia in the setting of chlorthalidone use and SARS-CoV-2 infection, and to demonstrate the challenges of managing this patient given her infectious status. METHODS: This was a case report. CASE: A 65-year-old woman taking chlorthalidone for hypertension presented to the emergency room with headache, pain, and blurry vision in both eyes and was found to be in bilateral acute angle closure. On laboratory investigation, she was severely hyponatremic and also tested positive for SARS-CoV-2. B-scan ultrasound demonstrated an apparent supraciliary effusion in the right eye. Following stabilization of her intraocular pressures with medical management, she ultimately underwent cataract extraction with iridectomies and goniosynechiolysis in both eyes. CONCLUSIONS: We report a rare case of bilateral acute angle-closure glaucoma associated with hyponatremia. Chlorthalidone use and perhaps SARS-CoV-2 infection may have contributed to this electrolyte abnormality and unique clinical presentation. In addition, we discuss the challenges of managing this complex patient with active SARS-CoV-2 infection during the pandemic.
Glaucoma is a multifactorial disease resulting in the death of retinal ganglion cells (RGCs) and irreversible blindness. Glaucoma-associated RGC death depends on the proapoptotic and proinflammatory activity of membrane-bound Fas ligand (mFasL). In contrast to mFasL, the natural cleavage product, soluble Fas ligand (sFasL) inhibits mFasL-mediated apoptosis and inflammation and, therefore, is an mFasL antagonist. DBA/2J mice spontaneously develop glaucoma and, predictably, RGC destruction is exacerbated by expression of a mutated membrane-only FasL gene that lacks the extracellular cleavage site. Remarkably, one-time intraocular adeno-associated virus-mediated gene delivery of sFasL provides complete and sustained neuroprotection in the chronic DBA/2J and acute microbead-induced models of glaucoma, even in the presence of elevated intraocular pressure. This protection correlated with inhibition of glial activation, reduced production of TNF-α, and decreased apoptosis of RGCs and loss of axons. These data indicate that cleavage of FasL under homeostatic conditions, and the ensuing release of sFasL, normally limits the neurodestructive activity of FasL. The data further support the notion that sFasL, and not mFasL, contributes to the immune-privileged status of the eye.
Glaucoma is a neurodegenerative disease with a structural change of the optic nerve head, leading to visual field defects and ultimately blindness. It has been proposed that glaucoma is associated with increased mortality, but previous studies had methodological limitations (selective study samples, lack of data on potential confounders, self-reported or secondary data on glaucoma diagnoses). We evaluated the association between diagnosed glaucoma and mortality in the population-based National Health and Nutrition Examination Survey (NHANES), a representative health survey in the United States. The survey cycles 2005-2006 and 2007-2008 included an extensive ophthalmic examination with fundus photography, which were used to derive standardized glaucoma diagnoses. Risk of all-cause mortality was assessed with multivariable Cox proportional hazards regression models accounting for the complex survey design of NHANES. Time to death was calculated from the examination date to date of death or December 31, 2015 whichever came first. 5385 participants (52.5% women) were eligible, of which 138 had glaucoma at baseline, and 833 died during follow-up. Participants with glaucoma were more likely to be older than those without glaucoma (mean age 69.9 vs. 56.0 years). Mean follow-up time was 8.4 years for participants with glaucoma, and 8.6 years for participants without glaucoma. Glaucoma was associated with increased mortality in an unadjusted Cox regression model (hazard ratio 2.06, 95% confidence interval 1.16 to 3.66), but the association was no longer statistically significant after adjusting for age and sex (hazard ratio 0.74, 95% confidence interval 0.46 to 1.17). Additional adjustment for a range of potential confounders did not significantly change the results. In this representative population-based study, we found no evidence of increased mortality risk in glaucoma patients.
We report a rare case of traumatic corneal perforation with Ahmed glaucoma valve (AGV) tube. A 5-year-old female child, diagnosed with refractory glaucoma, had undergone AGV implantation, presented with the posterior migration of AGV tube after trauma to the eye. The detailed ocular history, ophthalmic findings, clinical course and surgical management are discussed.
Pigmentary glaucoma (PG) is a common glaucoma subtype that results from release of pigment from the iris, called pigment dispersion syndrome (PDS), and its deposition throughout the anterior chamber of the eye. Although PG has a substantial heritable component, no causative genes have yet been identified. We used whole exome sequencing of two independent pedigrees to identify two premelanosome protein (PMEL) variants associated with heritable PDS/PG. PMEL encodes a key component of the melanosome, the organelle essential for melanin synthesis, storage and transport. Targeted screening of PMEL in three independent cohorts (n = 394) identified seven additional PDS/PG-associated non-synonymous variants. Five of the nine variants exhibited defective processing of the PMEL protein. In addition, analysis of PDS/PG-associated PMEL variants expressed in HeLa cells revealed structural changes to pseudomelanosomes indicating altered amyloid fibril formation in five of the nine variants. Introduction of 11-base pair deletions to the homologous pmela in zebrafish by the clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 method caused profound pigmentation defects and enlarged anterior segments in the eye, further supporting PMEL's role in ocular pigmentation and function. Taken together, these data support a model in which missense PMEL variants represent dominant negative mutations that impair the ability of PMEL to form functional amyloid fibrils. While PMEL mutations have previously been shown to cause pigmentation and ocular defects in animals, this research is the first report of mutations in PMEL causing human disease.
PURPOSE: A genetic correlation is the proportion of phenotypic variance between traits that is shared on a genetic basis. Here we explore genetic correlations between diabetes- and glaucoma-related traits. DESIGN: Cross-sectional study. METHODS: We assembled genome-wide association study summary statistics from European-derived participants regarding diabetes-related traits like fasting blood sugar (FBS) and type 2 diabetes (T2D) and glaucoma-related traits (intraocular pressure (IOP), central corneal thickness (CCT), corneal hysteresis (CH), corneal resistance factor (CRF), cup-disc ratio (CDR), and primary open-angle glaucoma (POAG)). We included data from the National Eye Institute Glaucoma Human Genetics Collaboration Heritable Overall Operational Database, the UK Biobank and the International Glaucoma Genetics Consortium. We calculated genetic correlation (r) between traits using linkage disequilibrium score regression. We also calculated genetic correlations between IOP, CCT and selected diabetes-related traits based on individual level phenotype data in two Northern European population-based samples using pedigree information and Sequential Oligogenic Linkage Analysis Routines (SOLAR). RESULTS: Overall, there was little r between diabetes- and glaucoma-related traits. Specifically, we found a non-significant negative correlation between T2D and POAG (r=-0.14; p=0.16). Using SOLAR, the genetic correlations between measured IOP, CCT, FBS, fasting insulin and hemoglobin A1c, were null. In contrast, genetic correlations between IOP and POAG (r ≥0.45; p≤3.0E-04) and between CDR and POAG were high (r =0.57; p=2.8E-10). However, genetic correlations between corneal properties (CCT, CRF and CH) and POAG were low (r range: -0.18 - 0.11) and non-significant (p≥0.07). CONCLUSION: These analyses suggest there is limited genetic correlation between diabetes- and glaucoma-related traits.