OBJECTIVES: Maintaining independence in daily activities is an important treatment outcome for people with Alzheimer’s disease (AD) and their families. Dependence levels and care needs in people with AD were assessed using a revised scale derived from the Alzheimer’s Disease Cooperative Study – Activities of Daily Living (ADCS-ADL), a widely used measure of basic and instrumental ADLs (bADLs and iADLs). Dependence was scored on a six-stage scale from completely independent to incontinent and/or unable to transfer without assistance.

METHODS: Revision of the original algorithm underlying this measure was carried out to clarify previous areas of ambiguity and propose rules for missing data. The revised algorithm was applied to data from three randomised double-blind, placebo-controlled studies to assess the efficacy of crenezumab (CREAD, CREAD2) and semorinemab (Tauriel) in participants with early (prodromal-to-mild) AD.

RESULTS: Applying the revised algorithm to CREAD and CREAD2 participants (N=1619), at baseline 20.8% were completely independent (level 0); 11.8% required some supervision with at least one ADL (level 1); 32.2% required support with multiple iADLs (level 2); 24.0% required help with all iADLs, supervision of bADLs or could not do tasks outside the home independently (level 3); and 11.2% needed physical help with bADLs (levels 4 and 5). Baseline Clinical Dementia Rating Scale – Sum of Boxes scores correlated with dependence levels (r=0.54, p<.0001). From baseline to Week 77, 47.9% of participants (n=427/892 at Week 77) experienced an increased level of dependence. In Tauriel, caregiver-reported hours of support for iADLs and bADLs at baseline (using Resource Utilization in Dementia - Lite Version) correlated with dependence levels (r=0.34, p<.0001 and r=0.30, p<.0001 respectively).

CONCLUSIONS: The ADCS-ADL Dependence Scale enables assessment of dependence in people with AD. Revisions to the algorithm provide an easily interpretable supplementary approach to interpreting the ADCS-ADL and assessing the impact of novel AD treatments on dependence and care needs.