title: Early diagnosis of mild cognitive impairment and mild dementia through basic and instrumental activities of daily living: Development of a new evaluation tool.
abstract: Assessment of activities of daily living (ADL) is paramount to determine impairment in everyday functioning and to ensure accurate early diagnosis of neurocognitive disorders. Unfortunately, most common ADL tools are limited in their use in a diagnostic process. This study developed a new evaluation by adopting the items of the Katz Index (basic [b-] ADL) and Lawton Scale (instrumental [i-] ADL), defining them with the terminology of the International Classification of Human Functioning, Disability and Health (ICF), adding the scoring system of the ICF, and adding the possibility to identify underlying causes of limitations in ADL.
  
  
  
  The construct validity, interrater reliability, and discriminative validity of this new evaluation were determined. From 2015 until 2016, older persons (65-93 y) with normal cognitive ageing (healthy comparison [HC]) (n = 79), mild cognitive impairment (MCI) (n = 73), and Alzheimer disease (AD) (n = 71) underwent a diagnostic procedure for neurocognitive disorders at the geriatric day hospital of the Universitair Ziekenhuis Brussel (Brussels, Belgium). Additionally, the ICF-based evaluation for b- and i-ADL was carried out. A global disability index (DI), a cognitive DI (CDI), and a physical DI (PDI) were calculated. The i-ADL-CDI showed high accuracy and higher discriminative power than the Lawton Scale in differentiating HC and MCI (area under the curve [AUC] = 0.895, 95% CI .840-.950, p = .002), MCI and AD (AUC = 0.805, 95% CI .805-.734, p = .010), and HC and AD (AUC = 0.990, 95% CI .978-1.000, p < .001). The b-ADL-DI showed significantly better discriminative accuracy than the Katz Index in differentiating HC and AD (AUC = 0.828, 95% CI .759-.897, p = .039). This study was conducted in a clinically relevant sample. However, heterogeneity between HC, MCI, and AD and the use of different methods of reporting ADL might limit this study.
  
  
  
  This evaluation of b- and i-ADL can contribute to the diagnostic differentiation between cognitively healthy ageing and neurocognitive disorders in older age. This evaluation provides more clarity and nuance in assessing everyday functioning by using an ICF-based terminology and scoring system. Also, the possibility to take underlying causes of limitations into account seems to be valuable since it is crucial to determine the extent to which cognitive decline is responsible for functional impairment in diagnosing neurocognitive disorders. Though further prospective validation is still required, the i-ADL-CDI might be useful in clinical practice since it identifies impairment in i-ADL exclusively because of cognitive limitations.
authors.affiliation: Department of Geriatrics, Universitair Ziekenhuis Brussel, Brussels, Belgium.|Frailty in Ageing Research Group (FRIA), Vrije Universiteit Brussel, Brussels, Belgium.|Department of Occupational Therapy, Artevelde University College Ghent, Ghent, Belgium.
authors.forename: Elise
authors.identifier: 0000-0001-5341-5339
authors.initials: E
authors.lastname: Cornelis
authors.affiliation: Department of Geriatrics, Universitair Ziekenhuis Brussel, Brussels, Belgium.|Frailty in Ageing Research Group (FRIA), Vrije Universiteit Brussel, Brussels, Belgium.|Department of Gerontology (GERO), Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: Ellen
authors.initials: E
authors.lastname: Gorus
authors.affiliation: Department of Geriatrics, Universitair Ziekenhuis Brussel, Brussels, Belgium.|Frailty in Ageing Research Group (FRIA), Vrije Universiteit Brussel, Brussels, Belgium.|Department of Gerontology (GERO), Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: Ingo
authors.identifier: 0000-0002-5418-7048
authors.initials: I
authors.lastname: Beyer
authors.affiliation: Department of Geriatrics, Universitair Ziekenhuis Brussel, Brussels, Belgium.|Frailty in Ageing Research Group (FRIA), Vrije Universiteit Brussel, Brussels, Belgium.|Department of Gerontology (GERO), Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: Ivan
authors.identifier: 0000-0002-6820-9586
authors.initials: I
authors.lastname: Bautmans
authors.affiliation: Frailty in Ageing Research Group (FRIA), Vrije Universiteit Brussel, Brussels, Belgium.|Department of Occupational Therapy, Artevelde University College Ghent, Ghent, Belgium.|Department of Gerontology (GERO), Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: Patricia
authors.identifier: 0000-0003-4861-7838
authors.initials: P
authors.lastname: De Vriendt
mesh_terms: D000203:Activities of Daily Living / Q000523:psychology*; D000368:Aged; D000369:Aged, 80 and over; D001530:Belgium; D060825:Cognitive Dysfunction / Q000175:diagnosis*; D003704:Dementia / Q000175:diagnosis*; D042241:Early Diagnosis; D005260:Female; D015577:Geriatric Assessment / Q000379:methods*; D006801:Humans; D008297:Male