An economic evaluation of early assessment for Alzheimer's disease in the United Kingdom
ABSTRACT Diagnosing and treating patients with Alzheimer's disease (AD) at an early stage should improve the quality of life of the patient and caregiver. In the United Kingdom, cost-effectiveness of early assessment of individuals presenting with subjective memory complaints and treating those with AD with donepezil was evaluated.
A discrete event simulation of AD progression and the effect of treatment interventions was developed. Patient-level data from donepezil trials and a 7-year follow-up registry were used to model correlated longitudinal rates of change in cognition, behavior, and function. Other epidemiological and health services data, including estimates of undiagnosed dementia and delays in diagnosis, were based on published sources. Simulated individuals were followed up for 10 years.
In the base-case estimates, 17 patients need to be assessed to diagnose one patient with AD, resulting in an average assessment cost of £4100 ($6000; $1 US = £0.68 UK) per patient diagnosed (2007 cost year). In comparison with a scenario without early assessment or pharmacologic treatment, early assessment reduces health care costs by £3600 ($5300) per patient and societal costs by £7750 ($11,400). Savings are also substantial compared with treatment without early assessment, averaging £2100 ($3100) in health care costs, and £5700 ($8400) in societal costs. Results are most sensitive to estimates of patient care costs and the probability of patients reporting subjective memory complaints. In probabilistic sensitivity analysis, early assessment leads to savings or is highly cost-effective in the majority of cases.
Although early assessment has significant up-front costs, identifying AD patients at an early stage results in cost savings and health benefits compared with no treatment or treatment in the absence of early assessment.
Full-textDOI: · Available from: Luis Hernandez, Oct 31, 2014
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ABSTRACT: ABSTRACT Background: The Cambridge Cognitive Examination-Revised (CAMCOG-R) is a sensitive screening tool for the early diagnosis of dementia in older adults. Overall performance on the CAMCOG-R is influenced by educational attainment. Few studies have, however, examined the association between educational attainment and performance on the individual CAMCOG subscales. We aimed to address this question in a sample from a low-and middle-income country (LAMIC), where resource constraints may have compromised access to, and quality of, education for many older adults. Methods: Participants, all over 60 years of age, were 51 cognitively healthy community-dwelling volunteers and 47 individuals diagnosed with mild-moderate stage Alzheimer's disease (AD). Most participants had some high school education. They were administered the CAMCOG-R under standardized conditions. Results: Within both the control and AD patient groups, there were significant associations between years of completed education and CAMCOG-R total score, MMSE score, and CAMCOG-R Language subscale score. In both groups, level of education was not associated with scores on these subscales: in controls, recent memory, R 2 = .21, p = .055, learning memory, R 2 = .16, p = .398, attention/calculation, R 2 = .19, p = .467, and perception, R 2 = .18, p = .984; in AD patients, recent memory, R 2 = .14, p = .340, learning memory, R 2 = .03, p = .680, perception, R 2 = .09, p = .723, and attention/calculation, R 2 = .19, p = .097. Conclusions: Some CAMCOG-R subscale scores were more strongly associated with educational attainment than others. Importantly, however, performance on the recent memory and learning memory subscales was not affected by education. These subscales are sensitive indicators of amnestic mild cognitive impairment (MCI) and early AD. These subscales may therefore remain valid for use as an AD screening tool in resource-poor healthcare settings.International Psychogeriatrics 11/2014; DOI:10.1017/S1041610214002233 · 1.89 Impact Factor
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ABSTRACT: The clinical challenge in subjective cognitive impairment (SCI) is to identify which individuals will present cognitive decline. We created a statistical model to determine which variables contribute to SCI and mild cognitive impairment (MCI) versus Alzheimer's disease (AD) diagnoses. A total of 993 subjects diagnosed at a memory clinic (2007-2009) were included retrospectively: 433 with SCI, 373 with MCI and 187 with AD. Descriptive statistics were provided. A logistic regression model analyzed the likelihood of SCI and MCI patients being diagnosed with AD, using age, gender, Mini-Mental State Examination score, the ratio of β-amyloid 42 divided by total tau, and phosphorylated tau as independent variables. The SCI subjects were younger (57.8 ± 8 years) than the MCI (64.2 ± 10.6 years) and AD subjects (70.1 ± 9.7 years). They were more educated, had less medial temporal lobe atrophy (MTA) and frequently normal cerebrospinal fluid biomarkers. Apolipoprotein E4/E4 homozygotes and apolipoprotein E3/E4 heterozygotes were significantly less frequent in the SCI group (6 and 36%) than in the AD group (28 and 51%). Within the regression model, cardiovascular risk factors, confluent white matter lesions, MTA and central atrophy increased the AD likelihood for SCI subjects. SCI patients form a distinct group. In our model, factors suggesting cardiovascular risk, MTA and central atrophy increased the AD likelihood for SCI subjects.
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ABSTRACT: Objective cost estimates and source of cost differences are needed across the spectrum of cognition, including Cognitively Normal (CN), mild cognitive impairment (MCI), newly discovered dementia, and prevalent dementia. Subjects were a subset of the Mayo Clinic Study of Aging stratified-random sampling of Olmsted County, MN, residents aged 70 to 89 years. A neurologist reviewed provider-linked medical records to identify prevalent dementia (review date = index). Remaining subjects were invited to participate in prospective clinical/neuropsychological assessments; participants were categorized as CN, MCI, or newly discovered dementia (assessment date = index). Costs for medical services/procedures 1-year pre-index (excluding indirect and long-term care costs) were estimated using line-item provider-linked administrative data. We estimated contributions of care-delivery site and comorbid conditions (including and excluding neuropsychiatric diagnoses) to between-category cost differences. Annual mean medical costs for CN, MCI, newly discovered dementia, and prevalent dementia were $6042, $6784, $9431, $11,678, respectively. Hospital inpatient costs contributed 70% of total costs for prevalent dementia and accounted for differences between CN and both prevalent and newly discovered dementia. Ambulatory costs accounted for differences between CN and MCI. Age-, sex-, education-adjusted differences reached significance for CN versus newly discovered and prevalent dementia and for MCI versus prevalent dementia. After considering all comorbid diagnoses, between-category differences were reduced (e.g., prevalent dementia minus MCI (from $4842 to $3575); newly discovered dementia minus CN (from $3578 to $711)). Following the exclusion of neuropsychiatric diagnoses from comorbidity adjustment, between-category differences tended to revert to greater differences. Cost estimates did not differ significantly between CN and MCI. Substantial differences between MCI and prevalent dementia reflected high inpatient costs for dementia and appear partly related to co-occurring mental disorders. Such comparisons can help inform models aimed at identifying where, when, and for which individuals proposed interventions might be cost-effective. Copyright © 2015 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.Alzheimer's & dementia: the journal of the Alzheimer's Association 04/2015; DOI:10.1016/j.jalz.2015.01.007 · 17.47 Impact Factor