Health-related resource use and costs in elderly adults with and without mild cognitive impairment.

OBJECTIVES: To assess differences in resource use and cost between older adults with and without mild cognitive impairment (MCI) over time. DESIGN: Multicenter, longitudinal study. SETTING: Sixty-eight Alzheimer's Disease Cooperative Study (ADCS) sites in the United States. PARTICIPANTS: Two hundred fifty-nine individuals diagnosed with MCI and 107 cognitively normal elderly adults followed annually for 3 years. MEASUREMENTS: The Resource Use Instrument (RUI) was used to capture medical and nonmedical care use. Generalized linear latent and mixed models were used to estimate differences in resource use and costs in older adults with and without MCI after controlling for clinical and demographic characteristics. RESULTS: At baseline, average annual direct medical cost per person was substantially higher for participants with MCI ($6,499) than for those without ($2,969) P < .001). Informal care use was also substantially higher (33% vs 8.4%, P < .001). Results from multivariate analyses of longitudinal data show that, after controlling for participant and informant characteristics, direct medical costs were 44% higher for participants with MCI than for those without. Participants with MCI were almost five times as likely to use informal care as those without. Number of medical conditions and older age were associated with higher medical cost. Worse functional and cognitive status, older age, being married, and being female were associated with higher likelihood of informal care use. Having an adult child informant was associated with higher likelihood of using informal care. CONCLUSION: The RUI captured differences in resource use and costs between individuals with and without MCI. Clinicians who care for individuals with MCI should address informal care needs early in the disease course.

Health state valuation in mild to moderate cognitive impairment: feasibility of computer-based, direct patient utility assessment.

BACKGROUND: Most patients with dementia will, at some point, need a proxy health care decision maker. It is unknown whether persons with various degrees of cognitive impairment can reliably report their health-related preferences. METHODS: The authors performed health state valuations (HSVs) of current and hypothetical future health states on 47 pairs of patients with mild to moderate cognitive impairment and their caregivers using computer-based standard gamble, time tradeoff, and rating scale techniques. RESULTS: Patients' mean (SD) age was 74.6 (9.3) years. About half of the patients were women (48%), as were most caregivers (73%), who were on average younger (mean age= 66.2 years, SD= 12.2). Most participants were white (83%); 17% were African American. The mean (SD) Mini-Mental State Examination (MMSE) score of patients was 24.2 (4.6) of 30. All caregivers and 77% of patients (36/47) completed all 18 components of the HSV exercise. Patients who completed the HSV exercise were slightly younger (mean age [SD]= 74.1 [8.5] v. 75.9 [11.8]; P = 0.569) and had significantly higher MMSE scores (mean score [SD] = 25.0 [4.3] v. 21.4 [4.4]; P = 0.018). Although MMSE scores below 20 did not preclude the completion of all 18 HSV ratings, being classified as having moderate cognitive impairment was associated with a lower likelihood of completing all scenario ratings (44% v. 82%). Patient and caregiver responses showed good consistency across time and across techniques and were logically consistent. CONCLUSION: Obtaining HSVs for current and hypothetical health states was feasible for most patients with mild cognitive impairment and many with moderate cognitive impairment. HSV assessments were consistent and reasonable.

Empirical assessment of a research advance directive for persons with dementia and their proxies.

OBJECTIVES: To evaluate a research advance directive for persons with established dementia diagnoses and their family caregivers or proxies. DESIGN: Prospective randomized, controlled trial. SETTING: Three clinics, one each in Ohio, Kentucky, and Illinois. PARTICIPANTS: At the end of separate interviews about enrollment choices in five types of hypothetical research projects, 149 persons with established dementia diagnoses and their family proxies were randomized to jointly complete the Planning Ahead Together (PAT) document, a research advance directive (n=69) or to remain in the control group (n=80). INTERVENTION: The directive was assessed at two points: immediately after sample members received naturally occurring invitations to participate in other studies and again 2 years after initial enrollment. MEASUREMENTS: Personal enrollment rates, reported ease of enrollment decision for patients and proxies, and proxy comfort were compared between the experimental and control groups. RESULTS: Forty-one dyads were reinterviewed immediately after consent discussions for other trials. Forty-seven patients and 106 proxies were interviewed at 2-year follow-up. There was no evidence immediately after a trial enrollment opportunity or in the follow-up interview that the research advance directive (PAT) assisted patients or proxies. Enrollment rates, decision ease, and proxy comfort and certainty were similar in the PAT and control groups. CONCLUSION: Patient and proxy experience making hypothetical decisions in the interview may have affected enrollment decisions by the PAT and control groups. Although the low number of recruitment attempts and the natural attrition of the geriatric population limit conclusions about effectiveness that may be drawn from this unique data set, the feasibility of a research advance directive is clearly demonstrated.

ADCS Prevention Instrument Project: quality of life assessment (QOL).

Information about quality of life (QOL) is valuable in evaluating pharmaceutical agents but it is not adequately assessed in many dementia drug trials. In prevention trials, following participants to conversion to AD requires QOL scales appropriate for both normal and cognitively impaired individuals. Our objective was to evaluate the utility of several scales for subject or informant QOL assessment: Quality of Life-AD; Quality of Life Activity Inventory; SF-36; SF-12 (a shortened version of the SF-36); and Satisfaction with Life Scale. Measurements were collected from 644 subject-study partner pairs, half of whom completed the instruments at the clinic and half at home. Three-month test-retest data were collected. Scales administered at home or in clinic did not differ significantly. Subject self-ratings showed a wide range for all scales. Test-retest intraclass coefficients ranged from 0.67 to 0.77. Moderately high interscale associations suggest that the scales are measuring common aspects of QOL but are not equivalent. Furthermore, they differed with respect to associations with demographic variables and QOL determinants. We conclude that the QOL scores at baseline show sufficient range and reliability to suggest they will have utility in tracking QOL through conversion to dementia.

ADCS Prevention Instrument Project: pilot testing of a book club as a psychosocial intervention and recruitment and retention strategy.

Both psychosocial and biologic interventions may delay or prevent Alzheimer disease. Staying mentally active may help older people maintain their cognitive abilities. In the Alzheimer Disease Cooperative Study Prevention Instrument Project a book club was introduced as a recruitment and retention device. A 3-arm study was designed and included: a nonrandomized, self-selected group (n=211) who chose not to participate in the book club, and 2 groups randomly assigned to receive 2 books per year in individual self-improvement (n=210) or community involvement (n=207) categories. Participants reported their reactions to the selections and other reading behaviors. Results from the first 2 years revealed that most book club participants agreed with Likert-type statements indicating the readings were enjoyable (P<0.001), had an impact on their thinking (P=0.01), and were shared by them with others (P=0.002). Respondents in the community involvement group agreed more strongly with these statements than those in the self-improvement category. Comments from participants in response to open-ended questions in the reader survey revealed such themes as developing plans for successful aging and reflecting on attitudes and behaviors in their own lives. Further longitudinal analyses are planned to determine whether the book club influenced retention and whether participation was associated with slowing cognitive decline.

An empirical basis for domains in the analysis of dependency in the activities of daily living (ADL): results of a confirmatory factor analysis of the Cleveland Scale for Activities of Daily Living (CSADL).

This study examines the empirical basis for dividing activities of daily living (ADLs) into broad behavioral domains. Following an exploratory factor analysis of results from the Cleveland Scale for Activities of Daily Living (CSADL), a two-factor model of ADLs was tested in a confirmatory factor analysis using two groups of demented patients. The model, which included a Basic and an Instrumental factor, was confirmed. Comparison of the item composition of the CSADL factors with a priori domains used by other ADL scales suggested that the results of the present study are broadly generalizable. The two factors are correlated, and cautions were raised concerning the likelihood that many ADL items may reflect both basic and instrumental domains.

Independence of changes in behavior from cognition and function in community-dwelling persons with Alzheimer's disease: a factor analytic approach.

The authors' main objective was to investigate the relationship between changes in psychopathological, cognitive and activity of daily living (ADL) instrument scores over 12 months in community-dwelling persons with Alzheimer's disease (AD). A secondary objective was to evaluate the validity of dividing the Clinical Dementia Rating (CDR), a global dementia staging instrument into cognitive and functional subscores. Changes in measures of psychopathology, cognition and function between the baseline and 12-month visits were entered into these post hoc analyses of data from a one-year clinical trial to evaluate behavioral, cognitive and functional assessment instruments for use in clinical trials with AD patients. Exploratory factor analysis was used to determine whether there was independence between changes in any of these three domains of interest for this disease population; participants were a cohort of 187 well-characterized, community-dwelling persons with AD. One-year change in the behavioral symptoms of this cohort of persons with AD was statistically independent from changes in scores on cognitive and functional measures. Some evidence of independence of 12 month changes in cognitive and functional measures was found. Cognitive and functional subscores for the CDR were supported. These findings suggest that changes in behavior and cognition in dementia may have distinct pathophysiologies.

Comorbidity of psychopathological domains in community-dwelling persons with Alzheimer's disease.

In this post hoc analysis of baseline responses to the CERAD Behavior Rating Scale for Dementia in a clinical trial of interventions for agitation in Alzheimer's disease (AD), the authors investigated the distribution of, and relationships between, agitation, depression, and psychosis in 148 individuals with AD. Prevalence of depressive symptoms was highest (78.4%), followed by agitation (77.6%) and psychotic symptoms (69.3%); 51.1% of the sample had symptoms in all 3 domains. Cross-sectionally, psychotic symptoms were most closely associated with Mini-Mental State Examination (MMSE) scores, while agitation was less so. Depressive symptoms were relatively consistently prevalent across MMSE levels. After controlling for the presence of agitated symptoms, psychosis and depression were significantly associated, but neither symptoms of psychosis nor of depression were associated with agitation when depression or psychosis, respectively, was controlled for. Significant psychopathological comorbidity should be considered in the design of clinical trials targeting particular psychopathology in this disease population.

Emergent psychopathology in Alzheimer's disease patients over 12 months associated with functional, not cognitive, changes.

In a large, well-characterized population of community-dwelling persons with Alzheimer's disease (AD), we investigated the emergence of behavioral symptomatology and its association with changes in cognitive, global-clinical, and functional status. Behavioral Rating Scale for Dementia (BRSD) item responses from 235 AD patients with varying levels of dementia severity and without significant behavioral disturbance were taken from the baseline and 12-month visits in a study of cognitive and behavioral instruments. Item-level analysis revealed new symptoms at every dementia severity level. The symptoms that emerged in the greatest proportion of patients were change in weight, change in appetite, diurnal confusion, uncooperativeness, restlessness, clingy behavior, loss of initiative, and change in sleeping pattern. Changes in cognitive status over the 12 months were associated with changes in functional status and not with the emergence of behavioral symptomatology; however, change in the latter two domains tended to be associated. The findings support the hypothesis that increasing behavioral disturbance is not strongly associated with decreasing cognitive status and that, except for psychotic symptoms, a previously observed association between dementia severity and behavioral status may have been mediated partly by changes in functional abilities.