title: Impaired vision and the ability to take medications.
abstract: OBJECTIVE
  To assess relationships between vision (contrast sensitivity, stereopsis, visual acuity) and a performance-based measure of ability to implement new medications.
  
  
  METHODS
  Cross-sectional analysis; prospective cohort study.
  
  
  METHODS
  Community-based.
  
  
  METHODS
  Three hundred thirty-five participants aged 73 to 82 in Year 3 of the Women's Health and Aging Study II, a representative sample of the two-thirds least-disabled community-dwelling women.
  
  
  METHODS
  Hopkins Medication Schedule Pillbox Ratio, a joint measure of accuracy and time, and a performance-based measure of ability to implement a prescription. Participants received written and verbal instructions for taking two medications and were directed to place pills in a pillbox accordingly. Vision assessments: contrast sensitivity (Pelli-Robson letter sensitivity chart), stereopsis (Randot Circles), and visual acuity (Early Treatment Diabetic Retinopathy Study eye chart).
  
  
  RESULTS
  Forty-four percent (148/335) of women incorrectly placed one or both medications. Each vision measure was positively associated with Pillbox Ratio scores and varied with cognition and time to completion. Better visual acuity, contrast sensitivity, and stereopsis were each associated with better performance in women with poor cognition who filled the pillbox quickly. Additionally, better visual acuity was associated with better performance in participants with good cognition who filled the pillbox slowly; better stereopsis was associated with better performance in participants with poor cognition who filled the pillbox slowly and whose stereoacuity was below normal.
  
  
  CONCLUSIONS
  Visual acuity, contrast sensitivity, and stereopsis should be considered potential risk factors for impaired ability to implement a medication regimen in older adults. Future research should investigate the role of vision, including contrast sensitivity and stereopsis, on performance of other instrumental activities of daily living.
authors.affiliation: Clinical Research Branch, National Institute on Aging, Baltimore, Maryland 21225, USA. windhamgw@grc.nia.nih.gov
authors.forename: Beverly Gwen
authors.initials: BG
authors.lastname: Windham
authors.forename: Michael E
authors.initials: ME
authors.lastname: Griswold
authors.forename: Linda P
authors.initials: LP
authors.lastname: Fried
authors.forename: Gary S
authors.initials: GS
authors.lastname: Rubin
authors.forename: Qian-Li
authors.initials: QL
authors.lastname: Xue
authors.forename: Michelle C
authors.initials: MC
authors.lastname: Carlson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D015350:Contrast Sensitivity; D003430:Cross-Sectional Studies; D003867:Depth Perception; D005260:Female; D006801:Humans; D010349:Patient Compliance; D004364:Pharmaceutical Preparations / Q000008:administration & dosage*; D011446:Prospective Studies; D012646:Self Administration; D014786:Vision Disorders / Q000503:physiopathology*; D014792:Visual Acuity
chemical_list: D004364:Pharmaceutical Preparations