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Eye Study (eye + study)
Kinds of Eye Study Selected AbstractsRegression-based Multivariate Linkage Analysis with an Application to Blood Pressure and Body Mass IndexANNALS OF HUMAN GENETICS, Issue 1 2007T. Wang Summary Multivariate linkage analysis has been suggested for the analysis of correlated traits, such as blood pressure (BP) and body mass index (BMI), because it may offer greater power and provide clearer results than univariate analyses. Currently, the most commonly used multivariate linkage methods are extensions of the univariate variance component model. One concern about those methods is their inherent sensitivity to the assumption of multivariate normality which cannot be easily guaranteed in practice. Another problem possibly related to all multivariate linkage analysis methods is the difficulty in interpreting nominal p-values, because the asymptotic distribution of the test statistic has not been well characterized. Here we propose a regression-based multivariate linkage method in which a robust score statistic is used to detect linkage. The p-value of the statistic is evaluated by a simple and rapid simulation procedure. Theoretically, this method can be used for any number and type of traits and for general pedigree data. We apply this approach to a genome linkage analysis of blood pressure and body mass index data from the Beaver Dam Eye Study. [source] Five-year incidence of visual impairment and blindness in older Icelanders: the Reykjavik Eye StudyACTA OPHTHALMOLOGICA, Issue 3 2010Elin Gunnlaugsdottir Abstract. Purpose:, This study examined age, sex and cause-specific 5-year incidence of visual impairment and blindness in a middle-aged and elderly Icelandic population. Methods:, The study cohort consisted of a population-based, random sample of citizens aged , 50 years. Of 1379 eligible subjects, 1045 underwent a baseline examination in 1996; 846 of the 958 survivors (88.2%) underwent a 5-year follow-up examination in 2001. All participants underwent an extensive ophthalmological examination including best corrected visual acuity (BCVA) using a Snellen chart. We used World Health Organization (WHO) criteria, which define visual impairment as BCVA in the better eye of < 6/18 and , 3/60 and blindness as BCVA in the better eye of < 3/60. We also used US criteria, which consider BCVA of < 6/12 and > 6/60 in the better eye to represent visual impairment and BCVA of , 6/60 in the better eye to represent blindness. The causes of incident visual loss in either eye were determined. Deterioration or improvement in vision were defined as a loss or gain of , 2 Snellen lines. Results:, According to WHO criteria, 5-year incidence of bilateral visual impairment and blindness were 1.07% (95% confidence interval [CI] 0.37,1.76) and 0.35% (95% CI 0.00,0.76), respectively. Using US criteria, equivalent incidence of bilateral visual impairment and blindness were 3.49% (95% CI 2.24,4.74) and 0.95% (95% CI 0.29,1.60), respectively. Age-related macular degeneration and cataract were the major causes of incident visual impairment and blindness. Conclusions:, Incidences of visual impairment and blindness increased significantly with age. Age-related macular degeneration, present in 75% of affected persons, was the most common cause of 5-year incident legal blindness in this middle-aged and elderly Icelandic population. [source] Epidemiology of exfoliation syndrome in the Reykjavik Eye StudyACTA OPHTHALMOLOGICA, Issue thesis3 2009Ársćll Már Arnarsson Abstract. Exfoliation syndrome (XFS) is a major risk factor for glaucoma. It is characterized by a pathological accumulation of polymorphic fibrillar material in the anterior segment of the eye. It is likely that the increase in intraocular pressure (IOP) seen in XFS patients is at least in part because of flakes of material clogging up the trabecular meshwork, and thereby increasing the resistance to outflow and increasing IOP. XFS glaucoma progresses more rapidly, is more resistant to medical treatment and has worse prognosis than other glaucomas. The prevalence of XFS has been found to vary greatly between different studies, raising the possibility of racial and/or environmental modulators. XFS has also been linked to other changes in ophthalmological structures such as; changes in central corneal thickness (CCT), steeper corneal curvature (CC) and nuclear lens opacifications. Some studies have found XFS to be associated with systemic diseases, mostly cardiovascular and cerebrovascular. Exposure to ultra-violet (UV) light has also been investigated as a possible culprit, along with several other plausible factors. The aim of the present study was to determine the prevalence and 5-year incidence of XFS, to establish possible risk factors and/or concomitant symptoms and finally to investigate the relationship between XFS and glaucomatous changes. The Reykjavík Eye Study (RES) is a prospective study based on a random sample from the Icelandic national population sample. The baseline examination was performed in the autumn of 1996, when 1045 persons older than 50 years participated. Of these, 846 (88.2% of survivors) participated in a follow-up 5 years later. All participants went through a standard examination protocol, and answered a comprehensive questionnaire on health and life style. In the prevalence study, XFS was found in 10.7% of subjects, more frequently in women and older persons. Five years later, a further 5.2% of those that participated in the follow-up study and had no signs of XFS at baseline were diagnosed having XFS. We found a strong correlation between IOP and XFS. No difference was found in the anterior segment parameters measured, but there was a significant loss of neural tissue in the XFS as demonstrated by measurements of cup/disk ratio. In conclusion, we find XFS to be frequent among Icelanders, increasing with age and more in women. Our diagnostic criteria are reliable over time. We have also identified possible risk factors that point to a role of antioxidants in the development of XFS. We find changes in corneal curvature and thickness more related to age than XFS. [source] Major eye diseases and risk factors associated with systemic hypertension in an adult chinese population: the Beijing Eye StudyACTA OPHTHALMOLOGICA, Issue 2009T LIBONDI Purpose To assess the relationship of hypertension with major eye diseases and other ocular parameters. Methods The Beijing Eye Study is a population-based study. Examination at baseline in 2001; follow-up examination in 2006; 3222 subjects had blood pressure measurements. All participants underwent a thourough ophthalmic examination and blood pressure measurement. Hypertension was defined as a systolic blood pressure ,140 mm Hg and/or a diastolic blood pressure ,90 mm Hg, and/or self-reported current treatment for hypertension with antihypertensive medication. Results Mean age of participants in the present study was 60.4±10.0 years. Hypertension was present in 1500 (46.6%) of the 3222 subjects who had their blood pressure measured. In multiple regression analysis, hypertension was associated with higher intraocular pressure (P = 0.005), arterio-venous nicking (P = 0.009),retinal vein occlusions (P = 0.02), and diabetic retinopathy (P = 0.02). Hypertension was not significantly associated with the prevalence of open-angle glaucoma (P = 0.19) or angle-closure glaucoma (P = 0.15), age-related macular degeneration (P = 0.73), nuclear cataract (P = 0.88), posterior subcapsular cataract (P = 0.30), cortical cataract (P = 0.10), or area of alpha zone (P=0.05) or beta zone of parapapillary atrophy (P = 0.95). Conclusion In Chinese persons, while controlling for other systemic parameters, hypertension was associated with increased intraocular pressure, retinal microvascular abnormalities, and prevalence of retinal vein occlusion and diabetic retinopathy. Hypertension was not associated significantly with age-related macular degeneration, age-related cataract, or glaucoma [source] The Beijing Eye StudyACTA OPHTHALMOLOGICA, Issue 3 2009Jost B. Jonas Abstract. Purpose:, This review presents and summarizes the findings of the Beijing Eye Study. Methods:, The Beijing Eye Study is a population-based study which included 4439 of 5324 subjects (aged , 40 years) who were initially examined in 2001. The study was repeated in 2006, when 3251 (73.2% of 4439, or 61.1% of 5324) of the original subjects participated. Participants underwent a series of examinations including: refractometry; pneumotonometry; biomicroscopy assisted by slit-lamp; optical coherence tomography of the anterior segment; photography of the cornea, lens, optic disc, macula and fundus; blood sampling for laboratory tests; blood pressure measurements, and determinations of anthropomorphic parameters. They were also asked to complete a questionnaire which included questions on socioeconomic parameters, and awareness and treatment of ocular and general diseases. Results:, We present normative data for refractive error, anterior segment measurements, intraocular pressure and optic disc structures and their associations, frequency and causes of visual impairment, blindness and visual field defects, prevalences of trachoma, pterygia, open-angle glaucoma and angle-closure glaucoma, cortical, nuclear and posterior subcapsular cataract, age-related macular degeneration, retinal vein occlusions, diabetes mellitus and diabetic retinopathy, myelinated nerve fibres, and retinitis pigmentosa, and associated and risk factors. Discussion:, These data may be helpful for dealing with public health issues in China and for assessing associated and risk factors of ocular and general diseases in general. [source] Correlation between vision- and health-related quality of life scoresACTA OPHTHALMOLOGICA, Issue 3 2009Brighu N. Swamy Abstract. Purpose:, To examine the correlation between health-related quality of life (HRQOL) scores [assessed using the generic Short Form Health Survey (SF-36) questionnaire] and vision-related quality of life (VRQOL) scores [assessed using the National Eye Institute Visual Function Questionnaire (NEI-VFQ25)]. Methods:, Cross-sectional analytic study. All surviving participants of the Blue Mountains Eye Study (n = 1952, aged 60 years and older) were invited to attend comprehensive eye examinations 10 years after baseline examinations and were asked to complete both questionnaires. Results:, Complete data were available for 1436 participants. After controlling for age, sex and the presence of either unilateral or bilateral visual impairment, the number of hospital admissions, chronic medical conditions and disabilities, we found that the composite NEI-VFQ score was significantly associated with the two main domains of the SF-36 survey: the summary physical component score (P < 0.001) and the mental component score (P < 0.001). There was relatively low correlation (r < 0.3) between the NEI-VFQ25 subscales and SF-36 subscales including the physical and mental composite scores. Conclusion:, VRQOL is influenced by both general health and HRQOL. However, there is a relatively low correlation between the individual subscales of these two quality of life questionnaires. [source] Frequency of non-arteritic anterior ischaemic optic neuropathy in crowded optic discs: the Beijing Eye StudyACTA OPHTHALMOLOGICA, Issue 3 2009Qi Sheng You No abstract is available for this article. [source] Prevalence of optic disc drusen in an adult Chinese population: the Beijing Eye StudyACTA OPHTHALMOLOGICA, Issue 2 2009Qi Sheng You Abstract. Purpose:, This study aimed to determine the prevalence of optic disc drusen and their associations with ocular and general parameters. Methods:, The Beijing Eye Study included 4439 of 5324 subjects invited to participate (response rate 83.4%). All subjects were aged , 40 years. The present investigation involved 8594 (96.8%) eyes of 4324 (97.4%) subjects from whom readable fundus photographs of at least one eye were available. The main outcome parameter was the presence of optic disc drusen defined as round, whitish bodies. Results:, Optic disc drusen were detected in nine (0.1 ± 0.05%) eyes of eight subjects (five women). The prevalence rate was 0.2 ± 0.07% (95% confidence interval 0.07,0.33%) per subject. Optic disc drusen were significantly associated with small optic discs (p < 0.001). They were not statistically associated with age (p = 0.90), gender (p = 0.73), intraocular pressure (p = 0.97), refractive error (p = 0.71), visual field defects (p = 0.47) or corrected visual acuity (p = 0.84). Conclusions:, Optic disc drusen are present in about two in 1000 adult Chinese people in Northern China. The main associated factor is a small optic disc. [source] Follow-up of glaucomatous eyes with optic disc haemorrhages: the Beijing Eye StudyACTA OPHTHALMOLOGICA, Issue 2 2009Liang Xu [source] Topical beta-blockers and the risk of cardiovascular mortalityACTA OPHTHALMOLOGICA, Issue 2007NM JANSONIUS Purpose: Recently, the Blue Mountains Eye Study reported an association between the use of topical timolol and cardiovascular mortality (Lee et al. Ophthalmology 2006). The purpose of the present study was to confirm or falsify this clinically very important finding, using data from the population-based Rotterdam Study. Methods: 6971 participants of the Rotterdam Study, a longitudinal population based study of all residents aged 55 years and older from a district of Rotterdam, The Netherlands, were followed from 1991 onwards. Medication use and morbidity were recorded continuously during follow-up. For the current analysis, baseline use of topical beta-blockers and systemic cardiovascular medication as well as baseline cardiovascular morbidity were used, aiming to follow the design of the Blue Mountains Eye Study as close as possible. Cause of death was registered up to 1-1-2005. Data were analysed using Cox regression; Hazard ratios of topical beta-blocker use were adjusted for age, sex, cardiovascular morbidity and use of systemic cardiovascular medication. Results: Mean age at baseline was 69 years (SD 9 years); 146 participants were using topical beta-blockers at baseline. 2726 participants died during follow-up (all cause mortality 40.1%), 611 (9.0%) had a cardiovascular cause of death. Hazard ratio of topical beta-blocker use was 0.80 (95% confidence interval 0.63-1.02; P=0.07) for all cause mortality and 0.78 (0.46-1.29; P=0.32) for cardiovascular mortality. Conclusions: In our data, the use of topical beta-blockers at baseline was not associated with either all cause mortality or cardiovascular mortality during follow-up. [source] Relationships between ocular dimensions and adult stature among participants in the Reykjavik Eye StudyACTA OPHTHALMOLOGICA, Issue 6 2005Thor Eysteinsson Abstract. Purpose:,To examine the relationships between adult stature, age and ocular dimensions in a large homogenous, white population. Methods:,We used the national population census for Reykjavik to select a random sample of adults aged 50 years or older. A total of 846 persons were examined. Scheimpflug images were used to measure anterior chamber depth. Ultrasound was used to measure axial length, lens thickness and vitreous chamber depth. An autorefracto-keratometer was used to measure autorefractive and keratometric values, including the radius of the corneal curvature. Stereo fundus photographs were taken of the optic disc and measurements of the disc diameters were made using computer software. Results:,Height correlated positively with axial length in the multivariate model (B = 0.020, 95% CI 0.006,0.034, p < 0.01). Both age and height showed significant correlations with vitreous chamber depth, where the correlation with age was negative (B = , 0.016, 95% CI , 0.006 to , 0.025, p < 0.005) and the correlation with height was positive (B = 0.019, 95% CI 0.005,0.034, p < 0.01). Height also showed a positive correlation with the radius of the corneal curvature (B = 0.008, 95% CI 0.004,0.011, p < 0.001). Anterior chamber depth had a negative correlation with age (B = , 0.013, 95% CI , 0.010 to , 0.016, p < 0.001), whereas lens thickness had a significant positive correlation with age (B = 0.019, 95% CI 0.016,0.023, p < 0.001). We found a significant negative correlation between axial length and refraction/spherical equivalent (r = , 0.595, p < 0.0001). Discussion:,Our results indicate that there is a significant relationship between height and several ocular dimensions in this adult population and confirms a negative correlation between axial length and refraction. [source] Angiotensin-converting enzyme inhibitors (ACEIs) and age-related maculopathy (ARM): cross-sectional findings from the Blue Mountains Eye StudyACTA OPHTHALMOLOGICA, Issue 3p1 2004Kathy H. C. Wu Abstract. Purpose:, To assess the relationship between the use of angiotensin-converting enzyme inhibitors (ACEIs) and prevalence of age-related maculopathy (ARM). Methods:, Eligible residents aged , 49 years were first examined in 1992,94 (Cross-section 1, n = 3654). Of these, 2335 were re-examined in 1997,99, together with an additional 1174 who became eligible after 1994 (Cross-section 2, n = 3509). Information regarding ACEI use was obtained and retinal photographs were graded using the Wisconsin ARM Grading System. Results:, In Cross-section 1, prevalence rates of late and early stage ARM were 1.3% and 4.3% among current ACEI users, and 2.0% and 4.8% among non-current users, respectively. In Cross-section 2, prevalence rates of late and early stage ARM were 2.3% and 11.3% among current ACEI users, and 1.3% and 9.3% among non-current users, respectively. After adjusting for age, sex and smoking, neither survey found any significant association between ACEI use and prevalence of either late or early ARM. Conclusions:, No significant cross-sectional associations were found between ACEI use and ARM prevalence in this population. [source] Risk factors for primary open-angle glaucoma in a Burmese population: the Meiktila Eye StudyCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 8 2007Robert J Casson FRANZCO Abstract Purpose:, To report the risk factors associated with primary open-angle glaucoma (POAG) in the Burmese population. Methods:, The Meiktila Eye study, a population-based cross-sectional study, included inhabitants 40 years of age and over from villages in the Meiktila District. Of 2481 eligible participants identified, 2076 participated in the study and sufficient examination data to diagnose glaucoma in at least one eye was obtained in 1997 participants. The ophthalmic examination included slit-lamp examination, tonometry, gonioscopy and dilated stereoscopic fundus examination. Definitions adhered to the International Society for Geographic and Epidemiological Ophthalmology's recommendations. Univariate and multivariate analyses of potential risk factors were performed. Results:, The overall prevalence of POAG was 2.0% (95% CI 0.9,3.1). In the univariate analysis, increasing age (P = 0.024), spherical equivalent (P = 0.01), axial length (P = 0.023) and intraocular pressure (IOP; P < 0.001) were significantly associated with POAG. And in the multivariate analysis, myopia <0.5 D (P = 0.049), increasing age and IOP (P < 0.001) were significant risk factors for POAG. Conclusion:, POAG in this Burmese population was associated with increasing age, axial myopia and IOP. [source] Increase in cataract surgery prevalence from 1992,1994 to 1997,2000: analysis of two population cross-sectionsCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 3 2004Ava Grace Tan BSc(Hons) Abstract Background:,Monitoring temporal changes in the demand for and provision of cataract surgery will be useful to health planners to meet resource needs and to estimate likely costs. The aim of this report was to compare the prevalence of cataract surgery in two population cross-sections of the Blue Mountains Eye Study (BMES), over an interval of around 6 years. Methods:,Cross-section I (n = 3654; mean age 66.2 years) consisted of BMES I participants (1992,1994). Cross-section II (n = 3509; mean age 66.7 years) consisted of BMES II (5-year) participants (n = 2335) plus persons who had moved into the area and age category since BMES I (n = 1174), so were newly eligible (1997,2000). Cataract surgery history was collected during interview and confirmed at examination. Results:,Over this 6-year period, there was a 32% increase in cataract surgery prevalence from 6.0% to 7.9%, or from 6.0% to 7.7% after age standardization. The increase in eye-specific prevalence was 43% (from 4.4% to 6.3%). It was more marked among persons aged 80+ years and for bilateral (from 12.3% to 19.9%) than unilateral surgery (from 10.7% to 11.8%). Best-corrected visual acuity (mean letters read correctly) after surgery (43 and 44 letters, respectively) was similar between cross-sections I and II. Conclusions:,The findings from a representative older population confirm that prevalent cataract surgery has increased substantially over the average 6-year period, from 1992,1994 to 1997,2000. [source] Patterns of glaucomatous visual field defects in an older population: the Blue Mountains Eye StudyCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 4 2003Anne J Lee BSc(Med) MB BS Abstract This report aims to describe the frequency of different patterns of visual field loss in open-angle glaucoma (OAG). The Blue Mountains Eye Study examined 3654 persons (aged 49+) during 1992,1994. Humphrey supra-threshold visual fields were performed in 88.9%. Those classified as glaucoma suspects had 30,2 full-threshold fields (9.2%). Of OAG cases (n = 108) with field tests in both eyes (n = 97), unilateral defects were present in 49 (50.5%) and bilateral in 48 (49.5%). Advanced field loss was found in 16 (15.4%) subjects and in 22 (10.9%) eyes, with bilateral loss present in 6 (6.2%) cases. Of all eyes of OAG cases (n = 201), 49 (24.4%) had no defects, 52 (25.9%) upper, 61 (30.3%) lower, and 17 (8.5%) had combined upper and lower loss. Of the upper and lower cases (n = 113), the types of defects included nasal step (36), arcuate (26), nasal plus arcuate (26), and hemispherical defects (25). Of subjects with fields in at least one eye (n = 104), there was a similar proportion in the worse eye of upper defects (28.8%), lower (31.7%), and combined upper and lower (24.0%). Undiagnosed OAG was more frequent in unilateral (65.3%) than bilateral (34.7%) cases (P = 0.003). This study reports the pattern of typical glaucomatous field loss in an older Australian population. [source] Impaired vision and other factors associated with driving cessation in the elderly: the Blue Mountains Eye StudyCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 3 2001Jagjit Singh Gilhotra MBBS ABSTRACT The aim of present study was to review vision and other factors associated with the cessation of driving. As part of the Blue Mountains Eye Study, detailed demographic information, driving status and medical history were taken. Visual acuity was measured during a standardized refraction and visual fields documented. Potential risk factors were decided a priori. Among the 3654 Eye Study participants, 2831 (77.5%) had driven a motor vehicle in the past, of whom 2379 (84.0%) were current drivers and 452 (16.0%, 95% CI 14.6,17.4%) said they had stopped driving. Older persons and women were more likely to have stopped driving. After adjusting for age and sex, sensory impairment affecting vision and hearing, plus chronic medical conditions and benzodiazepine use were significantly associated with cessation of driving. The study found that sensory impairment, particularly visual parameters, was associated with the decision to stop driving by older subjects. [source] Association between stature, ocular biometry and refraction in an adult population in rural Myanmar: the Meiktila eye studyCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 9 2007Hui Min Wu MD PhD Abstract Purpose:, To study the association between adult stature and ocular biometric parameters and refraction. Methods:, In a population-based cross-sectional ophthalmic survey of 2418 adults (,40 years old) living in the rural villages in central Myanmar, height and weight were measured using a standardized protocol, and body mass index was calculated. Non-cycloplegic refraction and corneal curvature were determined by an autorefractor. Ultrasound pachymetry was performed and ocular biometry, including axial length, anterior chamber depth, lens thickness and vitreous chamber length were measured using A-mode ocular ultrasonography. Results:, Height and weight were significantly correlated with age, gender and all the ocular biometric parameters, except lens thickness. After adjusting for age and gender, taller and heavier persons had eyes with longer axial length, deeper anterior and vitreous chambers, and flatter and thicker corneas than shorter persons. Height was not significantly correlated with refraction, and heavier persons tended to be less myopic (P < 0.001). Multivariate linear regression models revealed consistent results with the findings for association between height, weight and ocular biometry and refractive error. Conclusions:, Adult stature is independently associated with vitreous chamber length and corneal radius in this Burmese population. Heavier persons were slightly hyperopic. 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