Misplacing objects in mild to moderate Alzheimer's disease: a descriptive analysis from the VISTA clinical trial

BACKGROUND

Misplacing objects is a commonly reported symptom of Alzheimer's disease (AD) but it is little described systematically and conflicting characterisations (losing/forgetting the location of objects versus inappropriate placement) of this "warning sign" of dementia currently exist. Patient and carer descriptions of misplacing in clinical interviews are reported here.

METHODS

This was a secondary qualitative analysis of video recorded, open ended and semistructured clinical interviews with 130 community dwelling patients with mild to moderate AD (mean age 77 (7.7) years; 63% women; 67% mild AD) and their carers who participated in the Video Imaging Synthesis of Treating Alzheimer's Disease (VISTA) study, a 4 month, randomised, placebo controlled trial of galantamine. Employing a framework analysis approach, we summarised descriptive accounts of misplacing with relevant proportions.

RESULTS

Recurrent incidents of misplacing were described for 96/130 (74%) study patients, 45 of whom established treatment goals to track this problem. For most (78/96, 81%), misplacing was the inability to recall where an item had been set down or put away. Fewer patients (25/96, including 18 with recall misplacing) put objects in unusual or incorrect places. Patients were commonly aware of their misplacing (56/96, 58%) and were distressed by it (31/56). Patients who misplaced also displayed tendencies towards delusions/hallucinations (51/96, but only directly related to misplacing in 17 cases) and hiding items (15%)

CONCLUSION

Misplacing is a common phenomenon in mild to moderate AD. Here, misplacing was usually described as an inability to recall where an item was set down, more so than the inappropriate placement of items.

Effect of smoking on the accumulation of deficits, frailty and survival in older adults: a secondary analysis from the Canadian Study of Health and Aging

OBJECTIVES

Smoking has adverse effects on a variety of organ systems but little is known about the relationship between smoking and frailty. We aimed to investigate differences in health status between smoking and non smoking older adults.

DESIGN AND SETTING

The Canadian Study of Health and Aging, a nationally representative cohort study.

PARTICIPANTS

Nine thousand and eight community-dwelling men and women age 65 years and over at baseline.

MEASUREMENTS

Smoking status was determined using a Self-Assessed Risk Factor Questionnaire. Comparisons were made between never smokers, light smokers and heavy smokers with heavy smokers defined as those who smoked >or= 1 pack per day for 20 years or more. A frailty index (FI) generated from 40 self-reported health deficits was also modified to exclude 5 variables that could be directly attributed to smoking (e.g. cough). Decedent information was collected over 10 years.

RESULTS

Average FI values increased exponentially with age. For both men and women, heavy smokers were the most frail, light smokers had intermediate frailty status and never smokers were fittest. Modification of the FI did not impact these differences. Heavy smokers had significantly worse mortality than non smokers and higher rates of death in smokers persisted in the oldest old. 120 month survival curves, grouped for age, sex and smoking status showed that male smokers > 75 years had the highest mortality rates.

CONCLUSIONS

Smoking causes poorer health status at older ages which can be captured by the frailty index. Higher rates of death in smokers persist in the oldest old, with no emergence of "survivors" with fitness or longevity advantages.

Behavioural measures in frontotemporal lobar dementia and other dementias: the utility of the frontal behavioural inventory and the neuropsychiatric inventory in a national cohort study

BACKGROUND

Distinguishing between patients with frontotemporal lobar dementia (FTLD) and other dementing illnesses remains a difficult task for many clinicians. In this study, we aimed to provide further evidence for the construct validity of the frontal behavioural inventory (FBI) and assess its utility in differentiating FTLD patients from other groups using data from the Canadian Collaborative Cohort of Related Dementias (ACCORD) study.

METHOD

Baseline scores on the FBI and neuropsychiatric inventory (NPI) were compared among several clinical groups (n = 177).

RESULTS

The FBI discriminated a higher percentage of FTLD patients (>75% correct classification) from Alzheimer's disease and other groups compared to the NPI (54.2%).

CONCLUSION

This study provides good evidence for convergent validity between the FBI and NPI (r = 0.72), indicating that both measures capture similar psychopathology in this nationwide cohort.

Gait and posture impairment, parkinsonism and cognitive decline in older people

Our objective was to examine the frequency of gait and posture impairment and parkinsonism in 3 waves of the Canadians Study of Health and Aging (CSHA) and to determine their relationship to the development of cognitive impairment-not dementia (CIND) and dementia. A secondary analysis of a Canadian population-based cohort study was performed. People 65 years of age and older without cognitive impairment or dementia underwent examination for the presence of gait or posture impairment (GPI) or parkinsonism (based on the presence of 2/3 signs among resting tremor, rigidity or bradykinesia), both defined by a clinical examination. Risk for development of cognitive impairment or dementia was examined at 5 and 10 year follow up in pre-specified logistic regression models adjusted for age, sex, education and in separate models, frailty. The frequency of GPI ranged from 25 to 30% in cognitively unimpaired to 46-53% in CIND and demented subjects. Parkinsonism was more common with increasing cognitive impairment at each wave of the CSHA. Both GPI and parkinsonism predicted cognitive decline. Frailty reduced, but did not eliminate the impact of these motor measures and was itself a significant predictor of cognitive decline. In conclusion, motor impairment and frailty are common in older people and are associated with an increased risk of cognitive decline and dementia. GPI is common in CIND, while GPI and parkinsonism are both common in dementia.

Epilepsy and antiepileptic drug use in elderly people as risk factors for dementia

OBJECTIVE

To assess the role of epilepsy and antiepileptic drugs (AEDs) as risk factors for probable Alzheimer's disease (AD) and for all dementias in the Canadian Study of Health and Aging (CSHA). A secondary objective was to isolate the effect of the AED phenytoin on the development of dementia and AD.

METHODS

The cohort consists of 5376 participants aged 65 years or older with no evidence of dementia, defined as Modified Mini-Mental State (3MS) score > or =78. Primary exposure was self-report or clinical diagnosis of epilepsy at baseline (n=39), or self-report of AED therapy (n=67). Primary outcomes were development of dementia, defined as 3MS<78, or AD, determined by clinical examination using standard criteria, during a 5-year follow-up period. People whose 3MS score remained > or =78 served as the comparison group.

RESULTS

People reporting AED use at baseline had an age, sex and baseline 3MS adjusted odds ratio (OR) of 2.11 (95% CI 1.11 to 4.01) for developing dementia compared to those not taking AEDs at baseline. The association remained significant using only phenytoin as the exposure. No significant association was found between AED use and development of AD, nor between epilepsy and development of either AD or dementia.

CONCLUSIONS

Older adults taking AEDs are at a significantly higher relative risk of developing dementia than those not taking AEDs. Further investigation of this finding is warranted.

Epidemiological and clinical trials evidence about a preventive role for statins in Alzheimer's disease

This paper reviews epidemiological and clinical trials data about whether statin use reduces the risk of Alzheimer's disease (AD). The available information has come in three waves. The initial, mostly cross-sectional observational reports suggested that statins might prevent dementia. Next, two large clinical trials with cognitive add-on studies showed no benefit and neither did the third wave, again with observational studies. The latter were mostly longitudinal, and were critical of the first studies for not adequately addressing confounding by indication (i.e. that patients with dementia would be denied statins). Most recently, new data from the Canadian Study of Health and Aging have produced a mixed result. While methodological considerations are clearly important in understanding why the reports are so variable, there might also be merit in differentiating between statins, based on their presumed - and variable - mechanisms of action in dementia prevention, before concluding that the initial reports are entirely artefactual. Still, the first reports appear to have overestimated the extent of protection, so that unless there are important effects achievable with specific statins, a more than a modest role for statins in preventing AD seems unlikely.

A vascular risk factor index in relation to mortality and incident dementia

To develop a method for quantifying risks of death and dementia in relation to vascular risk factors the Gothenburg H-70 1901-02 birth cohort was studied (n=380, was followed over 20 years, with 103 incident dementia cases). Separate vascular risk factor indices were calculated using 23 vascular risk factors to predict: (i) dementia-free-survival, and (ii) incident dementia derived from post hoc optimal separation of affected and unaffected cases. Classification of adverse outcomes (dementia/non-dementia; alive/dead) was assessed using receiver-operator characteristic (ROC) curves, and the area under the curve (AUC). Each index showed high separation between affected and unaffected cases. For dementia/non-dementia, the AUC was 0.74+/-0.02 for 10 year and 0.67+/-0.02 for 20 year; for death/survival, the AUC was 0.75+/-0.02 for 10 years and 0.79+/-0.03 for 20 years. Of note, few items were important in both indexes, and most showed reciprocal effects (e.g. decreased the risk of death but increased the risk of dementia). Our results suggest that vascular risk factor indexes can give robust estimates of dementia and life span prognoses in elderly people, but death and dementia have different risk profiles. This may be because of death being a competing risk for incident late-onset dementia.

Characterizing neuropsychiatric symptoms in subjects referred to dementia clinics

OBJECTIVE

To characterize the neuropsychiatric symptoms (NPS) of subjects classified as not cognitively impaired (NCI), cognitively impaired-not demented (CIND), and dementia.

METHODS

A Canadian Cohort Study of Cognitive Impairment and Related Dementias (ACCORD) is a longitudinal investigation of individuals referred to eight Canadian dementia centers for evaluation of cognitive impairment and neurobehavioral symptoms. Of the inception cohort of 804 subjects for whom the informant-based Neuropsychiatric Inventory (NPI) was completed at study entry, 35 were classified as NCI, 193 as CIND, and 576 as dementia. The three diagnostic groups were compared on each of the 12 NPI items. Within each diagnostic group, comparisons were also made between symptomatic (NPS+; total score > 1) and asymptomatic (NPS-; total score = 0) subjects on measures of general cognitive status and functional disability. A subset of the NCI and CIND individuals were also compared on a comprehensive neuropsychological test battery.

RESULTS

There was at least one NPI item reported in 60% of subjects with NCI, 74% with CIND, and 89% with dementia. The item scores for delusions, hallucinations, agitation, apathy, disinhibition, aberrant motor behavior, and problems with appetite were greater in dementia subjects than in NCI or CIND. There were no significant differences between subjects with NCI and CIND on any NPI item. For each diagnostic group, NPS+ subjects were more impaired on functional but not neuropsychological measures.

CONCLUSIONS

Across all levels of cognition, neuropsychiatric symptoms (NPS) are an important feature in individuals referred to dementia clinics. The current data suggest that NPS may precede cognitive deficits in individuals classified as not cognitively impaired and cognitively impaired-not demented.

Outcomes of incident mild cognitive impairment in relation to case definition

Definitions of mild cognitive impairment (MCI) vary, yielding conflicting results. For example, case definitions affect prevalence but not outcomes in prevalent cases. Our objective was to determine whether variation in case definitions affects outcomes in incident cases of MCI. The 5 year risks of death, institutionalisation, and dementia were evaluated in clinically examined incident MCI cases in the Canadian Study of Health and Aging. The definition of MCI was varied so as to include or relax combinations of diagnostic features from consensus criteria. Relative risks (RR) of each adverse outcome were highest in MCI case definitions that required subjective memory complaints (for example, RR of dementia = 26.4-38.7). Although each MCI definition conferred an increased risk of dementia, for each case definition 20-30% of survivors had no cognitive impairment at follow up. In this population based study, MCI represented a transitional state, but was heterogeneous, with substantial proportions recovering, regardless of how MCI was defined. Factors associated with recovery and non-progression in MCI require elucidation.

Size of the treatment effect on cognition of cholinesterase inhibition in Alzheimer's disease

BACKGROUND

Six cholinesterase inhibitors (ChEIs) have been tested in people with Alzheimer's disease, using methods currently required for regulatory approval. The clinical importance of their treatment effects is controversial.

OBJECTIVE

To determine whether cholinesterase inhibition produces treatment effects in Alzheimer's disease that are large enough to be clinically detectable.

METHODS

Overview analysis of published trials of ChEIs in which the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog) and a global clinical measure were primary outcomes. Two quantitative summary measures of the treatment effect (Cohen's d and the standardised response mean (SRM)) were calculated and presented as funnel plots. Observed cases analyses and intention to treat (ITT) with the last observation carried forward (LOCF) analyses were compared.

RESULTS

The median Cohen's d effect sizes (ES) using ITT samples with LOCF for the ADAS-Cog were: low dose of a ChEI (n = 8 studies) median ES = 0.15, range = 0.03-0.22; medium dose (n = 13) median ES = 0.23, range = 0.12-0.29; high dose (n = 9) median ES = 0.28, range = 0.01-0.31. In general, the ES were larger when calculated as SRMs (for example, high dose ChEI studies, median SRM = 0.47; range = 0.30-0.63) and highest in the observed cases analyses (for example, high dose median SRM = 0.56, range = 0.35-0.78). Global clinical scales produced similar estimates of ES (for example, high dose ChEI, ITT/LOCF median Cohen's d = 0.29, range = 0.20-0.47).

CONCLUSIONS

ChEIs produce small-moderate effect sizes in clinical trials which are reproducible and demonstrate a dose response. Better descriptions of the patterns of treatment response are needed to guide individual patient decisions about the effectiveness of treatment, but group effects are evident and appear large enough to be clinically detectable.

A Canadian cohort study of cognitive impairment and related dementias (ACCORD): study methods and baseline results

The overall objective of the Canadian Collaborative Cohort of Related Dementias (ACCORD) study is to describe the diagnostic distribution, natural history and treatment outcomes of individuals referred from the community to dementia clinics in Canada. Between 1997 and 1999, an inception cohort of 1,136 subjects entered into this longitudinal study. At the baseline assessment, 10.9% of the subjects were classified as "not cognitively impaired" (NCI), 30.1% as "cognitively impaired not demented" (CIND), and 59% as demented. A subclassification of CIND included amnestic 25.1%, vascular cognitive impairment 18.1%, psychiatric 17.2%, neurologic 7.3%, medical/toxic metabolic 3.5%, mixed 7.6% and not specified 19.0%. The percentage of the cohort referred with dementia increased progressively each decade, while the proportions of CIND and NCI decreased. Within the dementia group, Alzheimer's disease accounted for 47.2% of the subjects, mixed dementias 33.7%, vascular dementia 8.7%, frontotemporal degenerations 5.4%, dementia with Lewy bodies 2.5%, and unclassifiable 1.8%. The ACCORD cohort will allow a detailed study of the longitudinal course of CIND, and the longer-term outcomes of both treated and untreated dementia subjects.

Goal setting and attainment in Alzheimer's disease patients treated with donepezil

OBJECTIVES

To understand the treatment goals of Alzheimer's disease (AD) patients, carers, and physicians; to estimate whether clinically important goals are met during treatment with donepezil; and to compare a measure of goal attainment with standard measures used to evaluate AD treatment.

METHODS

In a 12 month phase IV trial, 108 patients with mild to moderate AD, their primary carers, and treating physicians set goals assigned to five domains, using Goal Attainment Scaling (GAS) as the primary outcome. Goal attainment was assessed quarterly. GAS scores were correlated with standard outcomes, including the Alzheimer's Disease Assessment Scale-Cognitive (ADAS-cog), and the Clinician's Interview-Based Impression of Change-Plus (CIBIC-plus).

RESULTS

Physicians set fewer goals (342, mean (SD) per patient=3 (1)) than patients/carers (855, mean=9 (3)), particularly in leisure (20% by physicians compared with 76% by patients/carers), and social interaction (24% versus 49%). Physicians observed statistically significant improvement in global goal attainment for six months, and patients/carers for nine months. Patients/carers described consistent goal attainment, whereas physicians observed variable effects, such as decline in cognition but improved social interaction and behaviour. Physician global GAS scores correlated highly with the CIBIC-plus at weeks 12 (r= -0.82) and 52 (r=-0.80), but not with the ADAS-cog (r=0.12 and r=-0.45, respectively). Patient/carer global GAS scores correlated moderately with the physician's CIBIC-plus (week 12 r=-0.51; week 52 r=-0.56), and nominally with the ADAS-cog.

CONCLUSIONS

Patients/carers and physicians differ in their expectations and impressions of treatment effects. Clinically important changes correlated only modestly with psychometric tests. Attainment of treatment goals does not accord with a simplistic model in which successful AD treatment means that all declines uniformly improve.

The Canadian Study of Health and Aging: organizational lessons from a national, multicenter, epidemiologic study

The Canadian Study of Health and Aging was a large, multidisciplinary, national core study--with a number of "add-on" investigations--of the epidemiology of dementia and the health of older people. This structure was a fiscally prudent way to balance between mandated and investigator-initiated inquiry. In hindsight, several important features of the study would be repeated. Future studies might profitably consider a longer funding period for analysis, and a more strategic approach to in-depth, supplementary studies.

Estimating the prevalence of dementia in elderly people: a comparison of the Canadian Study of Health and Aging and National Population Health Survey approaches

The Canadian Study of Health and Aging (CSHA) and the National Population Health Survey (NPHS) collected data on the prevalence of dementia in differing fashions. The CSHA used a two-stage method with objective testing and expert judgment, and the NPHS used self-report and proxy data. The present report compares estimates of prevalence and the methodology for ascertainment in the two surveys. The more detailed approach of the CSHA offers the more valid means of estimating prevalence and providing data on subtypes, and can be used in naturalhistory studies. TheNPHSmeasures, including a self/proxy report of diagnosed dementia and a derived cognitive measure, are not sufficiently valid for useful inferences to be made. However, the NPHS method can be improved through supplementation with data on functional disability, providing age group-specific point estimates closer to the CSHA's estimates of cognitive impairment and dementia from the community sample. Future waves of the NPHS may wish to include objective cognitive function measures as a cost-efficient and more accurate method of estimating the prevalence of the dementia syndrome without attempting to estimate the prevalence of particular causes of that syndrome.