PURPOSE: To examine the age- and gender-specific 5-year incidence of age-related maculopathy (ARM) and age-related macular degeneration (AMD) in citizens of Reykjavik. DESIGN: Population-based, prospective cohort study. PARTICIPANTS: The cohort was a population-based random sample of citizens 50 years and older. Of 1379 eligible subjects, 1045 had a baseline examination in 1996; 846 of the 958 survivors (88.2%) had a 5-year follow-up examination in 2001. METHODS: The incidence of various characteristics of drusen and pigmentary changes that are typical of ARM were determined using the international classification and grading system for ARM and AMD. MAIN OUTCOME MEASURES: Early ARM and AMD were assessed by masked grading of stereo fundus photographs. RESULTS: Hypopigmentation developed at 5 years in 10.7% of people 50 to 59 years of age (95% confidence interval [CI], 6.9-14.4) and in 25.7% those 70 to 79 years of age (95% CI, 18.4-33.0) at baseline. Age-related macular degeneration developed in no one who was 50 to 59 years of age at baseline. Geographic atrophy (GA) developed in 4.6% (95% CI, 1.2-7.9) and exudative AMD in none of those who were 70 years and older at baseline. CONCLUSIONS: Geographic atrophy is the predominant type of AMD in Iceland, and the ratio of GA to neovascular AMD is higher than in racially similar populations.
To examine the corneal endothelium and establish the 7-year cumulative incidence of cornea guttata (CG).
Population-based prospective cohort study with 573 participants (third wave of the Reykjavik Eye Study (RES) in 2008). Four hundred and thirty-seven subjects had either right or left eyes available for analysis after excluding confounding eye conditions. The baseline for eyes at risk for developing CG is the second wave of the RES in 2001. Participants underwent specular microscopy and a standardized eye examination.
The cumulative 7-year incidence of CG in either eye was estimated as a 95% confidence interval for the expected value for both genders combined (15-23%), for males (8-18%) and for females (19-29%). In right eye only, the 7-year cumulative incidence for both genders combined was estimated to be 6-11%. For genders combined and for males only, the data indicated no correlation between 7-year cumulated incidence and age at baseline. In women, however, the change of 7-year incidence for CG in at least one eye appeared to be correlated to age at baseline. Reduction of endothelial cell density for corneas with CG at baseline was found [CI (0.95)-132 ± 94].
The cumulative 7-year incidence of primary central CG for a middle-aged and older Caucasian population without history of potentially confounding eye disease has been established. Women tend to have higher incidence if onset occurs at middle age. If CG is present, the cell density and the cell size variation decrease within a 7-year period.
To investigate the association between age-related macular degeneration (AMD) and mortality in older persons.
Population-based prospective cohort study.
Participants 67 to 96 years of age (43.1% male) enrolled between 2002 and 2006 in the Age, Gene/Environment Susceptibility-Reykjavik Study.
Retinal photographs of the macula were acquired digitally and evaluated for the presence of AMD lesions using the Wisconsin Age-Related Maculopathy grading scheme. Mortality was assessed prospectively through 2013 with cause of death available through 2009. The association between AMD and death, resulting from any cause and specifically cardiovascular disease (CVD), was examined using Cox proportional hazards regression with age as the time scale, adjusted for significant risk factors and comorbid conditions. To address a violation in the proportional hazards assumption, analyses were stratified into 2 groups based on the mean age at death (83 years).
Mortality resulting from all causes and CVD.
Among 4910 participants, after a median follow-up of 8.6 years, 1742 died (35.5%), of whom 614 (35.2%) had signs of AMD at baseline. Cardiovascular disease was the cause of death for 357 people who died before the end of 2009, of whom 144 (40%) had AMD (101 with early disease and 43 with late disease). After considering covariates, including comorbid conditions, having early AMD at any age or having late AMD in individuals younger than 83 years (n = 4179) were not associated with all-cause or CVD mortality. In individuals 83 years of age and older (n = 731), late AMD was associated significantly with increased risk of all-cause mortality (hazard ratio [HR], 1.76; 95% confidence interval [CI], 1.20-2.57) and CVD-related mortality (HR, 2.37; 95% CI, 1.41-3.98). In addition to having AMD, older individuals who died were more likely to be male and to have low body mass index, impaired cognition, and microalbuminuria.
Competing risk factors and concomitant conditions are important in determining mortality risk resulting from AMD. Individuals with early AMD are not more likely to die than peers of comparable age. Late AMD becomes a predictor of mortality by the mid-octogenarian years.
PURPOSE: To establish a population profile of central corneal thickness (CCT), radius of the corneal curvature (CC) and intraocular pressure (IOP) and the relationships between them using non-contact techniques. METHODS: We used a population-based random sample of 415 male and 510 female Caucasians aged 50 years and older. CCT and the radius of CC were measured with Scheimpflug anterior segment photography. IOP was measured with air-puff tonometry. RESULTS: The mean IOP of right eyes was 15.1 mmHg (SD 3.3) among men and 15.8 mmHg among women (SD 3.1), which is a statistically significant difference. The mean radius of CC for male right eyes was 7.78 (SD 0.60) and for females 7.62 (SD 0.58) which is also statistically significant. Mean CCT for male right eyes was 0.528 mm (SD 0.041) and for females 0.526 mm (SD 0.037), which is not a significant difference. Linear regression analysis shows no relationship between the radius of CC and IOP or between age and radius of CC. Linear regression analysis of the relationship between CCT and IOP suggests higher IOP measurements with thicker corneas. There was no significant correlation between age and CCT. CONCLUSION: IOP was found to be independent of age and significantly higher in females than in males. Radius of CC was found to be age-independent and significantly steeper in females than in males. CCT appears to be independent of age and gender. Greater CCT is associated with higher mean IOP.
We test the hypothesis that cerebral microbleeds (CMB) and age-related macular degeneration (AMD), both linked to amyloid-ß deposition, are correlated. This study includes 4205 participants (mean age 76.2; 57.8% women) in the Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study (2002-2006). CMB were assessed from magnetic resonance images, and AMD was assessed using digital retinal images. Data were analyzed with multinomial logistic models controlling for major confounders. Evidence of CMB was detected in 476 persons (272 with strict lobar CMB and 204 with nonlobar CMB). AMD was detected in 1098 persons (869 with early AMD, 140 with exudative AMD, and 89 with pure geographic atrophy). Early and exudative AMD were not associated with CMB. The adjusted odds ratio of pure geographic atrophy was 1.62 (95% confidence interval 0.93-2.82, p = 0.089) for having any CMB, 1.43 (0.66-3.06, p = 0.363) for strict lobar CMB, and 1.85 (0.89-3.87, p = 0.100) for nonlobar CMB. This study provides no evidence that amyloid deposits in the brain and AMD are correlated. However, the suggestive association of geographic atrophy with CMB warrants further investigation.
Cites: Am J Epidemiol. 2007 May 1;165(9):1076-8717351290
BACKGROUND: Age-related macular degeneration (AMD) is the most common cause of irreversible visual impairment in the developed world. The two forms of advanced AMD, geographic atrophy and neovascular AMD, represent different pathological processes in the macula that lead to loss of central vision. Soft drusen, characterized by deposits in the macula without visual loss, are considered to be a precursor of advanced AMD. Recently, it has been proposed that a common missense variant, Y402H, in the Complement Factor H (CFH) gene increases the risk for advanced AMD. However, its impact on soft drusen, GA, or neovascular AMD--or the relationship between them--is unclear. METHODS AND FINDINGS: We genotyped 581 Icelandic patients with advanced AMD (278 neovascular AMD, 203 GA, and 100 with mixed neovascular AMD/GA), and 435 with early AMD (of whom 220 had soft drusen). A second cohort of 431 US patients from Utah, 322 with advanced AMD (244 neovascular AMD and 78 GA) and 109 early-AMD cases with soft drusen, were analyzed. We confirmed that the CFH Y402H variant shows significant association to advanced AMD, with odds ratio of 2.39 in Icelandic patients (p = 5.9 x 10(-12)) and odds ratio of 2.14 in US patients from Utah (p = 2.0 x 10(-9)) with advanced AMD. Furthermore, we show that the Y402H variant confers similar risk of soft drusen and both forms of advanced AMD (GA or neovascular AMD). CONCLUSION: Soft drusen occur prior to progression to advanced AMD and represent a histological feature shared by neovascular AMD and GA. Our results suggest that CFH is a major risk factor of soft drusen, and additional genetic factors and/or environmental factors may be required for progression to advanced AMD.
Glaucoma is a leading cause of irreversible blindness. A genome-wide search yielded multiple single-nucleotide polymorphisms (SNPs) in the 15q24.1 region associated with glaucoma. Further investigation revealed that the association is confined to exfoliation glaucoma (XFG). Two nonsynonymous SNPs in exon 1 of the gene LOXL1 explain the association, and the data suggest that they confer risk of XFG mainly through exfoliation syndrome (XFS). About 25% of the general population is homozygous for the highest-risk haplotype, and their risk of suffering from XFG is more than 100 times that of individuals carrying only low-risk haplotypes. The population-attributable risk is more than 99%. The product of LOXL1 catalyzes the formation of elastin fibers found to be a major component of the lesions in XFG.
Comment In: Am J Ophthalmol. 2007 Dec;144(6):974-97518036875
BACKGROUND: Aviation involves exposure to ionizing radiation of cosmic origin. The association between lesions of the ocular lens and ionizing radiation is well-known. OBJECTIVE: To investigate whether employment as a commercial airline pilot and the resulting exposure to cosmic radiation is associated with lens opacification. METHODS: This is a population-based case-control study of 445 men. Lens opacification was classified into 4 types using the World Health Organization simplified grading system. These 4 types, serving as cases, included 71 persons with nuclear cataracts, 102 with cortical lens opacification, 69 with central optical zone involvement, and 32 with posterior subcapsular lens opacification. Control subjects are those with a different type of lens opacification or without lens opacification. Exposure was assessed based on employment time as pilots, annual number of hours flown on each aircraft type, time tables, flight profiles, and individual cumulative radiation doses (in millisieverts) calculated by a software program. Odds ratios were calculated using logistic regression. RESULTS: The odds ratio for nuclear cataract risk among cases and controls was 3.02 (95% confidence interval, 1.44-6.35) for pilots compared with nonpilots, adjusted for age, smoking status, and sunbathing habits. The odds ratio for nuclear cataract associated with estimation of cumulative radiation dose (in millisieverts) to the age of 40 years was 1.06 (95% confidence interval, 1.02-1.10), adjusted for age, smoking status, and sunbathing habits. CONCLUSION: The association between the cosmic radiation exposure of pilots and the risk of nuclear cataracts, adjusted for age, smoking status, and sunbathing habits, indicates that cosmic radiation may be a causative factor in nuclear cataracts among commercial airline pilots.
AIM: To examine the age- and gender-specific prevalent and 5-year incident risk of developing exfoliation syndrome (XFS). METHODS AND PARTICIPANTS: In a population-based random sample of citizens 50 years and older, 1045 persons had baseline examination in 1996; 846 of the 958 survivors (88.2%) had a follow-up examination in 2001. Following maximum dilatation of pupils, a diagnosis of exfoliation was established on slit-lamp examination. An extensive questionnaire was administered at baseline and follow-up. Prevalent and incident risk was then calculated using a multivariate analysis. RESULTS: The following variables were found to correlate significantly with prevalence risk of XFS at baseline: age, female gender, increased iris pigmentation, moderate use of alcohol and self-reported asthma. We also found that, compared with those who consumed dietary fibre-rich vegetables, green or yellow vegetables, and fruit less than once a month in their 20s and 40s, those consuming the same food items once or twice every 2 weeks were found to be less likely to have XFS. The same applied to those consuming dietary fibre rich once or twice every 2 weeks in their 40s and 60s. CONCLUSION: Food items that are possibly surrogates for antioxidative effect may correlate with decreased risk of XFS and increased iris pigmentation may correlate with increased risk. Given the large number of comparisons, these findings require validation through additional clinical studies. Increased age and female gender increase the likelihood of XFS.