Validation of the full and short forms of the CAMDEX interview for diagnosing dementia: evidence from a one-year follow-up study

Relationship between comprehensive geriatric assessment and amyloid PET in older persons with MCI

Background

The association between amyloid deposition and cognitive, behavioral and physical performance in mild cognitive impairment (MCI) due to Alzheimer’s disease (AD) has been poorly investigated, especially in older persons.

Methods

We studied the in vivo correlation between the amyloid deposition at Positron Emission Tomography (amyloid-PET) and the presence of memory loss, reduced executive function, neuropsychiatric symptoms and physical performance in older persons with MCI. Amyloid-PET was performed with 18F-flutemetamol and quantitatively analyzed.

Results

We evaluated 48 subjects, 21 men and 27 women. We performed in each patient a comprehensive geriatric assessment (CGA) including Mini Mental State Examination (MMSE), Clock Drawing Test (CDT), Activity Daily Living (ADL), Instrumental Activity of Daily Living (IADL), Neuropsychiatric inventory (NPI) questionnaire, 15 Geriatric Depression Scale (GDS), Short Physical Performance Battery (SPPB) and Hand Grip strength. Then, each patient underwent amyloid-PET. Mean age of the enrolled subjects was 74.6 ± 7.8 years. All of these subjects showed preserved cognitive function at MMSE > 24, while 29 of 48 subjects (61.0%) had altered CDT.

Mean NPI score was 6.9 ± 5.9. The mean value of SPPB score was 9.0 ± 2.6, while the average muscle strength of the upper extremities measured by hand grip was 25.6 ± 7.7 Kg. CT/MRI images showed cortical atrophic changes in 26 of the 48 examined subjects (54.0%), while cerebrovascular modifications were present in 31 subjects (64.5%). Pathological burden of amyloid deposits was detected in 25 of 48 (52.0%) patients with a mean value of global z-score of 2.8 (subjects defined as MCI due to AD).

After stratifying subjects in subclasses of clinical alterations, more probability of pathological amyloid deposition was found in subjects with impaired CDT and higher NPI score (O.R. = 3.45 [1.01–11.2], p = 0.04), with both impaired CDT and low physical performance (O.R. = 5.80 [1.04–32.2], p = 0.04), with altered CDT and high NPI score (O.R. = 7.98 [1.38–46.0], p = 0.02), and finally in those subjects with altered CDT, high NPI and low physical performance (O.R. = 5.80 [1.05–32.2], p = 0.04).

Conclusion

Our findings support the recent hypothesis that amyloid deposition could be associated with multiple cerebral dysfunction, mainly affecting executive, behavioral and motor abilities.

The sensitivity and specificity of subjective memory complaints and the subjective memory rating scale, deterioration cognitive observee, mini-mental state examination, six-item screener and clock drawing test in dementia screening

BACKGROUND

The effectiveness of dementia screening depends on the availability of suitable screening tools with good sensitivity and specificity to confidently distinguish normal age-related cognitive decline from dementia. The aim of this study was to evaluate the discriminant validity of 7 screening measures for dementia.

METHODS

A sample of 140 participants aged ≥60 years living in a residential facility for the aged were assessed clinically and assigned caseness for dementia using the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revised diagnostic criteria. Sensitivity and specificity of a selection of the following screening measures were tested using receiver operating characteristic (ROC) analysis for individual and combined tests: the Mini-Mental State Examination (MMSE), Six-Item Screener (SIS), Subjective Memory Complaint, Subjective Memory Complaint Clinical (SMCC), Subjective Memory Rating Scale (SMRS), Deterioration Cognitive Observee (DECO) and the Clock Drawing Test (CDT).

RESULTS

Using ROC analyses, the SMCC, MMSE and CDT were found to be 'moderately accurate' in screening for dementia with an area under the curve (AUC) >0.70. The AUCs for the SIS (0.526), SMRS (0.661) and DECO (0.687) classified these measures as being 'less accurate'. At recommended cutoff scores, the SMCC had a sensitivity of 90.9% and specificity of 45.7%; the MMSE had a sensitivity of 63.6% and a specificity of 76.0%, and the CDT had a sensitivity of 44.4% and a specificity of 88.9%. Combining the SMCC and MMSE did not improve their predictive power except for a modest increase when using the sequential rule.

CONCLUSION

The SMCC is composed of valid screening questions that have high sensitivity, are simple to administer and ideal for administration at the community or primary health care level as a first level of 'rule-out' screening. The MMSE can be included at a second stage of screening at the general hospital level and the CDT in specialist clinical settings. Sequential use of the SMCC and MMSE will improve the specificity of the former and the sensitivity of the latter.

Dentatorubral-pallidoluysian atrophy in three generations, with clinical courses from nearly asymptomatic elderly to severe juvenile, in an Australian family of Macedonian descent

We report a three-generation Caucasian family of Macedonian origin with dentatorubral-pallidoluysian atrophy (DRPLA), manifesting as very mild elderly onset, severe young adult onset, and severe childhood onset presentations in the three generations. The grandparental trinucleotide expansion size (52 repeats) is the smallest overtly pathogenic mutation yet reported. This 67-year-old man displayed only subtle neurological and cognitive deficits on formal examination and very slight signs on MRI. His son had developed a choreiform disorder at age 32 years, and by his 40s suffered severe dementia and motor decline. The grandson, the proband, presented as a teenager with progressive myoclonic epilepsy, dysarthria, ataxia, and cognitive decline, having manifesting learning difficulties from the age 5 years. Atrophin-1 expansion sizes of 52, 57, and 66 repeats were demonstrated in the three patients, respectively. Given an absence of any other indicative history in the family, we speculate that the mutation may have expanded from a 'high-end' normal allele to a pathogenic size at the grandfather's conception, or that one of his parents may have had a pathogenic mutation at the lowest end of the expanded range.

Early Assessment of Dementia: The Contribution of Different Memory Components

A broad memory test battery (reflecting explicit and implicit memory functioning) was administered to a heterogeneous sample of initially nondemented, community-dwelling elderly subjects. To examine the profile of preclinical dementia, subjects were tested twice: At baseline, all subjects were nondemented according to Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) criteria; 2 years later, a subgroup had developed dementia. Performance of the preclinically demented subjects was best characterized, relative to that of cognitively impaired subjects who did not develop dementia 2 years later, by an inability to benefit at recall from semantic relations and by absent repetition priming effects. The authors conclude that in addition to testing episodic memory functioning, it is important to be aware of semantic and implicit memory deficits in the early assessment of dementia.

Progress in clinical neurosciences: cognitive markers of progression in Alzheimer's disease

The objective of this review is to summarize the literature on Alzheimer's disease progression utilizing cognitive batteries to track change over time. Studies published in English and obtained through PubMed searches (1983-2004) were included (i) if they had a longitudinal design and followed probable Alzheimer's patients diagnosed by National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association or Diagnostic and Statistical Manual III/IV criteria, and (ii) if the techniques used for serial assessment were well-established in terms of validity and reliability. Longitudinal studies examining Alzheimer's disease progression report highly variable annual rates of change in decline rate. It remains unclear if this reflects disease subgroups or stage-related rate of decline. In conclusion a combination of stage-appropriate cognitive tests such as the Mattis Dementia Rating Scale and the Severe Impairment Battery, along with appropriate statistical methods to account for individual variability in decline rates, can capture the progression of Alzheimer disease and may be useful in further investigation.

[Dementia in patients of Hospital das Clínicas da UNICAMP]

OBJECTIVE

To report the relative frequencies of the causes of dementia in patients seen at UNICAMP Hospital.

METHOD

From 1989 to 1998, 261 dementia patients were admitted (89.7% studied retrospectively, and 10.3%, prospectively); mean age 63.5 years (+/-13.2), and education 3.6 years +/- 3.9; 25% illiterate). Diagnosis of dementia and its subtypes was based on DSM-IV criteria, CAMDEX, NINCDS-ADRDA, NINDS AIREN/ADDTC, Lund-Manchester, besides tap-test, including laboratory and neuroimaging examinations.

RESULTS

Sixty five patients (24.9%) had vascular dementia, 62 ( 23.7%) Alzheimer's, 29 (11.1%) depressive pseudodementia, 28 (10.9%) normal pressure hydrocephalus, 14(5.4%) mixed, 12 (4.6%) post-traumatic, 9 (3.4%) frontotemporal and 38 (14.5%) had diverse or unknown causes. Dementia was minimal or mild in 123 (47.1%), moderate in 95 (36.4%), and severe in 43 (16.5%).

CONCLUSION

Frequency of vascular dementia was 24.9%, Alzheimer's 23.7%, and normal pressure hydrocephalus 10.7%, in disagreement with that found in the neurological literature (20-30%, 50%, and 1-4%, respectively), probably because we are dealing with cases admitted to a tertiary university hospital. Epidemiological studies are needed to disclose the true proportion of these dementia syndromes in the population.