Performance-Based Measures of Everyday Function in Mild Cognitive Impairment

Abstract

Objective-The view that everyday function is preserved in mild cognitive impairment may be problematic. The objectives of this study were to determine the magnitude of impairment in everyday function in patients with mild cognitive impairment and Alzheimer's disease using a novel sensitive performance-based measure (the UCSD Performance-Based Skills Assessment; UPSA), contrast it with use of an informant-based measure (the Alzheimer's Disease Cooperative Study-Activities of Daily Living Inventory; ADCS-ADL), and model the relationship between cognitive measures and the performance-based measure.Method-Fifty cognitively normal elders, 26 patients who met criteria for amnestic mild cognitive impairment, and 22 patients who suffered from mild to moderate Alzheimer's disease were assessed on the UPSA, the ADCS-ADL, and a battery of neurocognitive tests.Results-Patients with mild cognitive impairment had significant impairments on the UPSA but not on the ADCS-ADL. The magnitude of the effect size between the cognitively healthy and the mild cognitive impairment group for the UPSA was large (d=0.86). A strong and significant relationship was observed between cognitive performances in speed (R 2 =0.37), episodic memory (R 2 =0.10), and semantic processing (R 2 =0.03) and UPSA score using multiple regression models. The psychometric properties of the UPSA were acceptable, as were its sensitivity and specificity in contrasts between cognitively normal elders and patients with mild cognitive impairment and between the latter group and patients with Alzheimer's disease.Conclusions-These findings indicate that performance-based measures of function may be a sensitive tool in studies of Alzheimer's disease and mild cognitive impairment and suggest the need for a reconceptualization of the relationship between cognition and function in mild cognitive impairment so that they can be usefully aligned.Mild cognitive impairment is a less-than-benign diagnosis because it is associated with an elevated risk of incident Alzheimer's disease and more rapid cognitive decline (1,2). The rate of conversion from mild cognitive impairment to Alzheimer's disease may be 10%-12% per year (3). Neuropathologically, mild cognitive impairment (in many but not all cases) appears to be a transitional state of evolving Alzheimer's disease (4,5 NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript imaging using the amyloid binding ligand carbon-11-PIB has suggested that the amyloid burden in mild cognitive impairment is intermediate between healthy comparison subjects and patients with Alzheimer's disease (6,7). By recommended diagnostic criteria, individuals with mild cognitive impairment have an impairment of 1.5 standard deviations in episodic memory but essentially preserved everyday function (8,9).Several lines of evidence suggest that the diagnostic criterion relating to function may be problematic. First, neuropsychiatric conditions with associated cognitive impairments are also reliably associated with sequelae in ...

Longitudinal Study of a Novel Performance-based Measure of Daily Function

“…In a preliminary study we compared patients with MCI, patients with mild AD who by diagnosis have functional impairments, and healthy age matched controls on the UPSA, as well as measures of cognition (e.g., episodic memory, semantic memory, executive function, speed). We found that patients with MCI had compromises in everyday functional competence and that the UPSA was strikingly sensitive to these (Goldberg et al, 2010). Additionally the UPSA outperformed an informant based measure on a variety of criteria.…”

P4–200: SIST‐M‐IR activities of daily living items that best discriminate the clinically normal elderly from those with mild cognitive impairment

“…Those scales include the CDR [4,5], the FAQ [4,5], the ADL-Prevention Instrument (ADL-PI) [24], and the Everyday Cognition [25]. Two performance-based IADL instruments have also been shown to successfully distinguish between CN elderly and MCI: the University of California, San Diego Performance-Based Skills Assessment [26] and the Financial Capacity Instrument [27]. All of these tests are clearly sensitive to early changes in AD.…”

Taking clinical judgment out of the equation : a call for the standardization of MCI diagnostic criteria and construction of a model to predict conversion to dementia.

“…Recent research has demonstrated that patients with MCI show significantly compromised functional abilities when evaluated with performance-based measures, and this trend extends to patients identified as having intact functioning by family members (Goldberg et al, 2010).…”

“…However, the results of this study do not support this delineation as both converters and nonconverters presented with functional decrements. In addition, prior research also points to this delineation as problematic for a number of reasons (Goldberg et al, 2010). First, medical and psychiatric conditions that are reliably associated with cognitive changes are, in turn, also reliably associated with changes in everyday functioning (Goldberg et al, 1990;Heaton et al, 1994).…”

“…First, medical and psychiatric conditions that are reliably associated with cognitive changes are, in turn, also reliably associated with changes in everyday functioning (Goldberg et al, 1990;Heaton et al, 1994). Second, given that cognitive decline is associated with changes in everyday functioning, the cognitive impairments characteristic of MCI should exact a graduated cost on function (Goldberg et al, 2010).…”