Quality of Life as an outcome in Alzheimer's disease and other dementias- obstacles and goals

Abstract

BackgroundThe number of individuals at risk for dementia will probably increase in ageing societies as will the array of preventive and therapeutic options, both however within limited economic resources. For economic and medical purposes valid instruments are required to assess disease processes and the efficacy of therapeutic interventions for different forms and stages of illness. In principal, the impact of illness and success of an intervention can be assessed with biomedical variables, e.g. severity of symptoms or frequency of complications of a disease. However, this does not allow clear judgement on clinical relevance or comparison across different diseases.DiscussionOutcome model variables such as quality of life (QoL) or health care resource utilization require the patient to appraise their own well-being or third parties to set preferences. In Alzheimer's disease and other dementias the evaluation process performed by the patient is subject to the disease process itself because over progress of the disease neuroanatomical structures are affected that mediate evaluation processes.SummaryPublished research and methodological considerations thus lead to the conclusion that current QoL-instruments, which have been useful in other contexts, are ill-suited and insufficiently validated to play a major role in dementia research, decision making and resource allocation. New models integrating biomedical and outcome variables need to be developed in order to meet the upcoming medical and economic challenges.

Developing a dementia-specific health state classification system for a new preference-based instrument AD-5D

“…Last but not least, there is evidence of mismatch between the EQ-5D and respondent generated attributes [22]. As such, the validity of the EQ-5D for use in resource allocation in dementia may be limited [23]. …”

Priority of Treatment Outcomes for Caregivers and Patients with Mild Cognitive Impairment: Preliminary Analyses

“…For this reason, some have argued that using patient and caregiver-reported outcomes, such as quality of life (QoL) [3] measures, is ill-suited to research in Alzheimer’s disease (AD) or related conditions [4]. However, modern nomenclature of neurodegenerative disease diagnosis recognizes an initial phase of the illness characterized by concerning, but mild cognitive impairments (MCI) with retained functional capacities.…”

Dementia quality of life instrument – construct and concurrent validity in patients with mild to moderate dementia

“…In dementia research, the assessment of quality of life (QoL) is recommended and valid instruments are needed in several languages for cross-national studies [1][2][3][4][5]. The debate on QoL for people with AlzheimerÕs disease very often refers to the conceptual model proposed by Lawton who claimed behavioural competence, positive and negative affect, the objective environment and subjective QoL as determinants of well-being in older adults [6][7][8][9][10][11][12]. Empirical data substantiate that QoL as perceived by people with dementia is moderately associated with depressive mood, slightly connected to activity participation but not consistently related to behavioural or cognitive disorders [13].…”