title: Composite Measures of Individual and Area-Level Socio-Economic Status Are Associated with Visual Impairment in Singapore.
abstract: OBJECTIVE
  To investigate the independent relationship of individual- and area-level socio-economic status (SES) with the presence and severity of visual impairment (VI) in an Asian population.
  
  
  METHODS
  Cross-sectional data from 9993 Chinese, Malay and Indian adults aged 40-80 years who participated in the Singapore Epidemiology of eye Diseases (2004-2011) in Singapore. Based on the presenting visual acuity (PVA) in the better-seeing eye, VI was categorized into normal vision (logMAR≤0.30), low vision (logMAR>0.30<1.00), and blindness (logMAR≥1.00). Any VI was defined as low vision/blindness in the PVA of better-seeing eye. Individual-level low-SES was defined as a composite of primary-level education, monthly income<2000 SGD and residing in 1 or 2-room public apartment. An area-level SES was assessed using a socio-economic disadvantage index (SEDI), created using 12 variables from the 2010 Singapore census. A high SEDI score indicates a relatively poor SES. Associations between SES measures and presence and severity of VI were examined using multi-level, mixed-effects logistic and multinomial regression models.
  
  
  RESULTS
  The age-adjusted prevalence of any VI was 19.62% (low vision = 19%, blindness = 0.62%). Both individual- and area-level SES were positively associated with any VI and low vision after adjusting for confounders. The odds ratio (95% confidence interval) of any VI was 2.11(1.88-2.37) for low-SES and 1.07(1.02-1.13) per 1 standard deviation increase in SEDI. When stratified by unilateral/bilateral categories, while low SES showed significant associations with all categories, SEDI showed a significant association with bilateral low vision only. The association between low SES and any VI remained significant among all age, gender and ethnic sub-groups. Although a consistent positive association was observed between area-level SEDI and any VI, the associations were significant among participants aged 40-65 years and male.
  
  
  CONCLUSIONS
  In this community-based sample of Asian adults, both individual- and area-level SES were independently associated with the presence and severity of VI.
authors.affiliation: Centre for Infectious Disease Epidemiology and Research, Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore.
authors.forename: Win
authors.initials: W
authors.lastname: Wah
authors.affiliation: Duke-NUS Graduate Medical School, Singapore, Singapore.|Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia.
authors.forename: Arul
authors.initials: A
authors.lastname: Earnest
authors.affiliation: Duke-NUS Graduate Medical School, Singapore, Singapore.|Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.
authors.forename: Charumathi
authors.initials: C
authors.lastname: Sabanayagam
authors.affiliation: Duke-NUS Graduate Medical School, Singapore, Singapore.|Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.|Department of Ophthalmology, National University of Singapore and National University Health System, Singapore, Singapore.
authors.forename: Ching-Yu
authors.initials: CY
authors.lastname: Cheng
authors.affiliation: Duke-NUS Graduate Medical School, Singapore, Singapore.|Department of Emergency Medicine, Singapore General Hospital, Singapore, Singapore.
authors.forename: Marcus Eng Hock
authors.initials: ME
authors.lastname: Ong
authors.affiliation: Duke-NUS Graduate Medical School, Singapore, Singapore.|Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.
authors.forename: Tien Y
authors.initials: TY
authors.lastname: Wong
authors.affiliation: Duke-NUS Graduate Medical School, Singapore, Singapore.|Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.|Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Australia.
authors.forename: Ecosse L
authors.initials: EL
authors.lastname: Lamoureux
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012846:Singapore; D012923:Social Class; D014786:Vision Disorders / Q000503:physiopathology*