***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: PURPOSE To study the relationship between baseline spherical equivalents ( SphE ) of refraction  and prevalent as well as incident age-related maculopathy ( pARM and iARM , respectively ) . METHODS The study was performed as part of the Rotterdam Study , a population -based , prospect i ve cohort study . The SphE ( in diopters ) , measured with autorefraction and subjective optimization , was recorded in 6209 subjects aged 55 years or more . Aphakic or pseudophakic eyes at baseline were excluded .  Stereoscopic transparencies of the macular region were grade d according to the International Classification and Grading System . ARM was defined as large soft drusen with pigmentary changes , or indistinct drusen , or atrophic or neovascular age-related macular degeneration ( AMD ) . For the prevalence analyses , ARM was classified into no , p(early)ARM , or pAMD , and in each subject the eye with the most advanced ARM and the corresponding refraction was selected . After a mean 5.2 years of follow-up , 4935 subjects had complete data for these incidence analyses . In each subject , the eye with iARM was selected . RESULTS The age- and gender-adjusted odds ratio ( OR ) of pARM ( n = 536 ) for every diopter of progress toward hyperopia was 1.09 ( 95 % confidence interval [CI]1.04 - 1.13 ) . For p(early)ARM ( n = 440 ) the OR was 1.09 ( 1.04 - 1.14 ) and for pAMD ( n = 96 ) the OR was 1.09 ( 1.00 - 1.19 ) . Baseline refraction was significantly associated with increased risk of iARM ( n = 497 ) . For each diopter of progress toward hyperopia the OR was 1.05 ( 95 % CI 1.01 - 1.10 ) . Additional adjustments for smoking , atherosclerosis , and blood pressure did not alter the relationship . CONCLUSIONS These population -based incidence data confirm results from prevalence and case-control studies that there is an association between hyperopia and ARM OBJECTIVE To describe the risk factors and associated population attributable risk for age-related maculopathy ( ARM ) and age-related macular degeneration ( AMD ) in Australians aged 40 years and older . METHODS Residents were recruited from 9 r and omly selected urban clusters and 4 r and omly selected rural clusters in Victoria , Australia . At locally established test sites , the following information was collected : visual acuity , medical and health history , lifetime  sunlight  exposure , dietary intake , and fundus photographs . Age-related maculopathy and AMD were grade d from the fundus photographs using an international classification and grading system . Backwards logistic regression was used to identify the independent risk factors for ARM and AMD . RESULTS The participation rate was 83 % ( n = 3271 ) among the urban residents and 92 % ( n = 1473 ) among the rural residents . Gradable fundus photographs of either eye were available for 4345 ( 92 % ) of the 4744 participants . There were 656 cases of ARM , giving a weighted prevalence of 15.1 % ( 95 % confidence limit [ CL ] , 13.8 , 16.4 ) ; and there were 30 cases of AMD , giving a weighted prevalence of 0.69 % ( 95 % CL , 0.33 , 1.03 ) . In multiple logistic regression , the risk factors for AMD were as follows : age ( odds ratio [ OR ] , 1.23 ; 95 % CL , 1.17 , 1.29 ) , smoked cigarettes for longer than 40 years ( OR , 2.39 ; 95 % CL , 1.02 , 5.57 ) , and ever taken angiotensin-converting enzyme inhibitors ( OR , 3.26 ; 95 % CL , 1.33 , 8.01 ) . The magnitude of all of these risk factors was slightly less for ARM , and having ever taken blood cholesterol-lowering medications was also significant ( OR , 1.67 ; 95 % CL , 1.12 , 2.47 ; P = .001 ) . CONCLUSION Smoking is the only modifiable risk factor for ARM and AMD , among the many environmental and systemic factors that were assessed PURPOSE To assess the prevalence and associated risk factors of age-related macular degeneration ( AMD ) in an elderly Chinese population in Taiwan . METHODS The Shihpai Eye Study was a survey of vision and ocular disease in an elderly Chinese population 65 years of age or older residing in Shihpai , Taipei , Taiwan . Of 2045 elderly residents r and omly sample d from the household registration data bank , 1361 ( 66.6 % ) underwent a detailed ophthalmic examination that included fundus color slides by fundus camera after pupil dilatation . Photographs were grade d according to the Wisconsin Age-Related Maculopathy Grading System . RESULTS Fundus photographs were available for 1105 ( 54.0 % in the eligible , 81.2 % in the ocular examined ) participants . The 47 ( 4.3 % ) participants who had ungradable fundus images were older and had more lens opacity . Of the 1058 gradable photographs , the prevalence of early AMD was 9.2 % ( 95 % confidence interval [ CI ] , 7.8 - 10.8 ) ; of late AMD , 1.9 % ( 95 % CI , 1.3 - 2.7 ) ; of soft drusen , 42.2 % ( 95 % CI , 39.7 - 44.8 ) ; of soft indistinct drusen , 4.1 % ( 95 % CI , 3.1 - 5.2 ) ; and of any pigmentary change , 8.6 % ( 95 % CI , 7.2 - 10.2 ) . Age was the most significant factor associated with both early and late AMD . The prevalence of early AMD rose from 5.0 % in the 65- to 69-year age group to 24.4 % in those 80 years of age and older ; and for late AMD , from 1.0 % to 9.0 % . Those who currently drank alcohol had a lower rate of early AMD than did the nondrinker ( adjusted odd ratio 0.32 , 95 % CI : 0.11 - 0.93 , P = 0.037 ) . CONCLUSIONS AMD is a common eye disease in the elderly Chinese people in Taiwan . The adjusted prevalence rate of exudative AMD is comparable to that in the Chinese people in the Multiethnic Study of Atherosclerosis ( MESA ) in the United States but is higher than in the Chinese people in the Beijing study in China . Further studies are needed to clarify the incidence and associated risk factors OBJECTIVE To investigate possible risk factors for age-related macular degeneration ( AMD ) in participants in the Age-Related Eye Disease Study ( AREDS ) . DESIGN Case-control study . PARTICIPANTS Of the 4757 persons enrolled in AREDS , 4519 persons aged 60 to 80 years were included in this study . The lesions associated with AMD ranged from absent in both eyes to advanced in one eye . MAIN OUTCOME MEASURES Stereoscopic color fundus photographs of the macula were used to place participants into one of five groups , based on the frequency and severity of lesions associated with AMD . Participants with fewer than 15 small drusen served as the control group . RESULTS Staged model building techniques were used to compare each of the four case groups with the control group . Increased age was a consistent finding of all four of the case groups compared with the control group , and all the following associations were age adjusted . Persons with either intermediate drusen , extensive small drusen , or the pigment abnormalities associated with AMD ( group 2 ) were more likely to be female , more likely to have a history of arthritis , and less likely to have a history of angina . Persons with one or more large drusen or extensive intermediate drusen ( group 3 ) were more likely to use  hydrochlorothiazide diuretics  and more likely to have arthritis . Hypertension , hyperopia , presence of lens opacities , and white race were also found more frequently in this group as well as in persons with neovascular AMD ( group 5 ) . Only persons in group 5 were more likely to have an increased body mass index , whereas persons with geographic atrophy ( group 4 ) as well as those in groups 3 and 5 were more likely to have completed fewer years in school or to be smokers . Those with geographic atrophy were also more likely to use thyroid hormones and antacids . CONCLUSIONS Our findings for smoking and hypertension , which have been noted in previous studies , suggest that two important public health recommendations , the avoidance of smoking and the prevention of hypertension , may reduce the risk of developing AMD . Other associations , such as those for hyperopia , lens opacities , less education , female gender , increased body mass index , and white race , which have been noted in other studies , are also seen in the AREDS population . The increased use of thyroid hormones and antacids in persons with geographic atrophy and the increased likelihood of arthritis or hydrochlorothiazide use in persons with one or more large drusen or extensive intermediate drusen have not been previously reported and need additional investigation PURPOSE To compare the ocular rigidity in vivo measurements of patients with age-related macular degeneration ( AMD ) and control subjects . DESIGN Prospect i ve comparative clinical study . METHODS The pressure-volume relation and the ocular rigidity coefficient were compared among 32 patients with AMD ( AMD group : 16 with neovascular and 16 with nonneovascular AMD ) and 44 age-matched control patients ( control group ) who underwent operation for cataract . This was achieved by an injection of 200 microl of a balanced salt solution ( in steps of 4.5 microl ) through the limbus in the anterior chamber , while the intraocular pressure was monitored continually with a transducer , up to the limit of 30 mm Hg . RESULTS The mean age ( AMD group : 69.89 + /- 15.92 years vs control group : 65.28 + /- 12.34 years ; P = .195 ) , gender ( AMD group : 13 female vs control group : 17 female ; P = .513 ) , eye 's axial length ( AMD group : 23.14 + /- 0.75 mm vs control group : 23.04 + /- 1.16 mm ; P = .725 ) of patients with AMD and the healthy control subjects were comparable . No statistically significant difference in ocular rigidity measurements between patients with AMD and control subjects ( AMD group : 0.0142 + /- 0.0077 microl(-1 ) vs control group : 0.0125 + /- 0.0049 microl(-1 ) ; P = .255 ) was found . When we examined separately the two subgroups of patients with AMD ( neovascular and nonneovascular AMD ) , the average ocular rigidity measurements were higher in patients with neovascular AMD vs both control subjects and patients with nonneovascular AMD ( neovascular AMD group : 0.0186 + /- 0.0078 microl(-1 ) vs control group : 0.0125 + /- 0.0048 microl(-1 ) [ P = .014 ] vs nonneovascular AMD group : 0.0104 + /- 0.0053 microl(-1 ) [ P = .004 ] ) . CONCLUSIONS Despite the limitations placed by the small sample of the examined cases , patients with neovascular AMD who are treated ( with photodynamic therapy ) have increased ocular rigidity measurements compared with patients with nonneovascular AMD and control patients OBJECTIVE To describe the prevalence of  age-related macular degeneration ( AMD ) in 4 racial/ethnic groups ( white , black , Hispanic , and Chinese ) that participated in the second examination of the Multi-ethnic Study of Atherosclerosis ( MESA ) . DESIGN Prospect i ve cohort study . PARTICIPANTS Six thous and one hundred seventy-six 45- to 85-year-old subjects selected from 6 United States communities . METHODS Fundus images were taken using a 45 degrees digital camera through dark-adapted pupils and were grade d for drusen size , type , area , increased retinal pigment , retinal pigment epithelial depigmentation , neovascular lesions , and geographic atrophy using the modified Wisconsin Age-Related Maculopathy Grading System . MAIN OUTCOME MEASURE Age-related macular degeneration . RESULTS Prevalences of AMD were 2.4 % ( black ) , 4.2 % ( Hispanic ) , 4.6 % ( Chinese ) , to 5.4 % ( white ) ( P<0.001 for any differences among groups ) . The highest prevalence of any AMD occurred in those 75 to 84 years old , varying from 7.4 % in blacks to 15.8 % in whites and Chinese ( P = 0.03 ) . Estimated prevalences of late AMD were 0.3 % ( black ) , 0.2 % ( Hispanic ) , 0.6 % ( white ) , and 1.0 % ( Chinese ) . These differences were marginally 
    Output:
    
However , no significant association was found between hyperopia or myopia and early AMD incidence .
Furthermore , neither prevalent nor incident late AMD was associated with refractive error .
Geographic location might play a role ; the heterogeneity became non-significant after stratifying these studies into Asian and non-Asian subgroups .
Refractive error is associated with early AMD but not with late AMD .