Detection of activities of daily living impairment in Alzheimer's disease and mild cognitive impairment using information and communication technology

Abstract

Background: One of the key clinical features of Alzheimer's disease (AD) is impairment in daily functioning. Patients with mild cognitive impairment (MCI) also commonly have mild problems performing complex tasks. Information and communication technology (ICT), particularly techniques involving imaging and video processing, is of interest in order to improve assessment. The overall aim of this study is to demonstrate that it is possible using a video monitoring system to obtain a quantifiable assessment of instrumental activities of daily living (IADLs) in AD and in MCI.

Methods: The aim of the study is to propose a daily activity scenario (DAS) score that detects functional impairment using ICTs in AD and MCI compared with normal control group (NC). Sixty-four participants over 65 years old were included: 16 AD matched with 10 NC for protocol 1 (P1) and 19 MCI matched with 19 NC for protocol 2 (P2). Each participant was asked to undertake a set of daily tasks in the setting of a "smart home" equipped with two video cameras and everyday objects for use in activities of daily living (8 IADLs for P1 and 11 for P2, plus 4 temporal execution constraints). The DAS score was then computed from quantitative and qualitative parameters collected from video recordings.

Results: In P1, the DAS score differentiated AD (DAS(AD,P1) = 0.47, 95% confidence interval [CI] 0.38-0.56) from NC (DAS(NC,P1) = 0.71, 95% CI 0.68-0.74). In P2, the DAS score differentiated MCI (DAS(MCI,P2) = 0.11, 95% CI 0.05-0.16) and NC (DAS(NC,P2) = 0.36, 95% CI 0.26-0.45).

Conclusion: In conclusion, this study outlines the interest of a novel tool coming from the ICT world for the assessment of functional impairment in AD and MCI. The derived DAS scores provide a pragmatic, ecological, objective measurement which may improve the prediction of future dementia, be used as an outcome measurement in clinical trials and lead to earlier therapeutic intervention.

Keywords: IADL; ICT; MCI; functional impairment.

Figure 1

DAS_.,P1 scores for AD patients and NC participants for protocol 1 (P1). The first line (A) represents the ratio of efficacy for the two groups (Grey dots for NC and Black dots for AD). Then the next lines (B–E) show the evolution of the index from ratio of efficacy (index 0) to DAS_.,P1 score (index 4) including omission (B), repetition (C), order error (D), and bad completion at the first attempt (E). Measurements represented for each participant j: (A) R_Eff = Index_0,P1(j) (Percentage of time spent in the room to behave directed to perform a listed activities). (B) ${\text{Index}}_{\text{1},\text{P1}}(\text{j})=[{\text{R}}_{\text{Eff}}(\text{j})]\times {\prod }_{\text{i}=1}^4{k}_{1,P1}^{{\text{a}}_{1,F}}$ (impact of omission mistakes on the R_Eff). (C) ${\text{Index}}_{2,\text{P1}}(\text{j})=[{\text{R}}_{\text{Eff}}(\text{j})]\times {\prod }_{\text{i}=1}^4{k}_{1,P1}^{{\text{a}}_{1,F1}(\text{j})}$ (cumulative impact of omission and repetition mistakes on the R_Eff). (D) ${\text{Index}}_{3,\text{P1}}(\text{j})=[{\text{R}}_{\text{Eff}}(\text{j})]\times {\prod }_{\text{i}=1}^2{k}_{1,P2}^{{\text{a}}_{1,F2}(j)}$ (cumulative impact of omission, repetition, and order mistakes on the R_Eff). (E) Final DAS score ${\text{S}}_{\text{j},\text{P}1}({\text{k}}_{1,\text{P}1,}\hspace{0.17em}{\text{k}}_{2,\text{P}1,}\hspace{0.17em}{\text{k}}_{3,\text{P1},}\hspace{0.17em}{\text{k}}_{4,\text{P1},})\hspace{0.17em}(\text{j})=[{\text{R}}_{\text{Eff}}(\text{j})]\times {\prod }_{\text{i}=1}^4{k}_{1,P1}^{{\text{a}}_{1,F1}\hspace{0.17em}(\text{j})}$ (cumulative impact of omission, repetition, order mistakes, and bad completion at the first attempt on the R_Eff).

Figure 2

Performance evaluation of the assessment methodology to classify observation data as AD group or NC group. (A) Specificity and sensitivity in function of the cutoff point of DAS_.,P1() scores. (B) Receiver operating curve associated with protocol 1. Abbreviations: AD, Alzheimer’s disease; DAS, daily activity scenario; NC, normal control.

Figure 3

DAS_.,P2 scores for MCI patients and NC participants for protocol 2 (P2). The first line (A) represents the ratio of efficacy for the two groups (Grey dots for NC and Black dots for MCI). Then the next lines (B–E) show the evolution of the index from ratio of efficacy (index 0) to DAS_.,P2 score (index 4) including omission (B), repetition (C), bad achievement of activities (D), and planning errors (E). Measurements represented for each participant j: (A) R_Eff = Index_0,P2 (j) (Percentage of time spent in the room to behave directed to perform a listed activities). (B) ${\text{Index}}_{1,\text{P}2}(\text{j})=[{\text{R}}_{\text{Eff}}(\text{j})]\times k_{1,P2}^{{\alpha }_{1,F2}\hspace{0.17em}(j)}$ (impact of omission mistakes on the R_Eff). (C) ${\text{Index}}_{2,\text{P}2}(\text{j})=[{\text{R}}_{\text{Eff}}(\text{j})]\times {\prod }_{\text{i}=1}^2{k}_{1,P2}^{a_{1,F2}\hspace{0.17em}(j)}$ (cumulative impact of omission and repetition (excluding repetition of leisure activities) mistakes on the R_Eff). (D) ${\text{Index}}_{3,\text{P}2}(\text{j})=[{\text{R}}_{\text{Eff}}(\text{j})]\times {\prod }_{\text{i}=1}^3{k}_{1,P2}^{a_{1,F2}\hspace{0.17em}(j)}$ (cumulative impact of omission, repetition (excluding repetition of leisure activities) mistakes and bad achievement of activities on the R_Eff). (E) Final DAS score ${\text{S}}_{\text{j},\text{P}2}\hspace{0.17em}({\text{k}}_{1,\text{P}2,}\hspace{0.17em}{\text{k}}_{2,\text{P}2,}\hspace{0.17em}{\text{k}}_{3,\text{P}2,}\hspace{0.17em}{\text{k}}_{4,\text{P}2,})\hspace{0.17em}(\text{j})=[\text{REff}(\text{j})]\times {\prod }_{\text{i}=1}^4{k}_{1,P2}^{{\text{a}}_{1,F2}\hspace{0.17em}(j)}$ (cumulative impact of omission, repetition (excluding repetition of leisure activities) mistakes, bad achievements of activities, and planification mistakes on the R_Eff).

Figure 4

Performance evaluation of the assessment methodology to classify observation data as MCI group or NC group. (A) Specificity and sensitivity in function of the cutoff point of DAS_.,P2() scores. (B) Receiver operating curve associated with the protocol 2. Abbreviations: DAS, daily activity scenario; MCI, mild cognitive impairment; NC, normal control.