Application of the NIA-AA Research Framework: Towards a Biological Definition of Alzheimer's Disease Using Cerebrospinal Fluid Biomarkers in the AIBL Study

BACKGROUND

The National Institute on Aging and Alzheimer's Association (NIA-AA) have proposed a new Research Framework: Towards a biological definition of Alzheimer's disease, which uses a three-biomarker construct: Aß-amyloid, tau and neurodegeneration AT(N), to generate a biomarker based definition of Alzheimer's disease.

OBJECTIVES

To stratify AIBL participants using the new NIA-AA Research Framework using cerebrospinal fluid (CSF) biomarkers. To evaluate the clinical and cognitive profiles of the different groups resultant from the AT(N) stratification. To compare the findings to those that result from stratification using two-biomarker construct criteria (AT and/or A(N)).

DESIGN

Individuals were classified as being positive or negative for each of the A, T, and (N) categories and then assigned to the appropriate AT(N) combinatorial group: A-T-(N)-; A+T-(N)-; A+T+(N)-; A+T-(N)+; A+T+(N)+; A-T+(N)-; A-T-(N)+; A-T+(N)+. In line with the NIA-AA research framework, these eight AT(N) groups were then collapsed into four main groups of interest (normal AD biomarkers, AD pathologic change, AD and non-AD pathologic change) and the respective clinical and cognitive trajectories over 4.5 years for each group were assessed. In two sensitivity analyses the methods were replicated after assigning individuals to four groups based on being positive or negative for AT biomarkers as well as A(N) biomarkers.

SETTING

Two study centers in Melbourne (Victoria) and Perth (Western Australia), Australia recruited MCI individuals and individuals with AD from primary care physicians or tertiary memory disorder clinics. Cognitively healthy, elderly NCs were recruited through advertisement or via spouses of participants in the study.

PARTICIPANTS

One-hundred and forty NC, 33 MCI participants, and 27 participants with AD from the AIBL study who had undergone CSF evaluation using Elecsys® assays. INTERVENTION (if any): Not applicable.

MEASUREMENTS

Three CSF biomarkers, namely amyloid β1-42, phosphorylated tau181, and total tau, were measured to provide the AT(N) classifications. Clinical and cognitive trajectories were evaluated using the AIBL Preclinical Alzheimer Cognitive Composite (AIBL-PACC), a verbal episodic memory composite, an executive function composite, California Verbal Learning Test - Second Edition; Long-Delay Free Recall, Mini-Mental State Examination, and Clinical Dementia Rating Sum of Boxes scores.

RESULTS

Thirty-eight percent of the elderly NCs had no evidence of abnormal AD biomarkers, whereas 33% had biomarker levels consistent with AD or AD pathologic change, and 29% had evidence of non-AD biomarker change. Among NC participants, those with biomarker evidence of AD pathology tended to perform worse on cognitive outcome assessments than other biomarker groups. Approximately three in four participants with MCI or AD had biomarker levels consistent with the research framework's definition of AD or AD pathologic change. For MCI participants, a decrease in AIBL-PACC scores was observed with increasing abnormal biomarkers; and increased abnormal biomarkers were also associated with increased rates of decline across some cognitive measures.

CONCLUSIONS

Increasing biomarker abnormality appears to be associated with worse cognitive trajectories. The implementation of biomarker classifications could help better characterize prognosis in clinical practice and identify those at-risk individuals more likely to clinically progress, for their inclusion in future therapeutic trials.

Genetic and Environmental Influences on Language Ability in Older Adults: Findings from the Older Australian Twins Study

We used a sub-sample from the Older Australian Twins Study to estimate the heritability of performance on three tests of language ability: Boston Naming Test (BNT), Letter/Phonemic Fluency (FAS) and Category/Semantic Fluency (CFT) Tests. After adjusting for age, sex, education, mood, and global cognition (GC), heritability estimates obtained for the three tests were 0.35, 0.59, and 0.20, respectively. Multivariate analyses showed that the genetic correlation were high for BNT and CFT (0.61), but low for BNT and FAS (0.17), and for FAS and CFT (0.28). Genetic modelling with Cholesky decomposition indicated that the covariation between the three measures could be explained by a common genetic factor. Environmental correlations between the language ability measures were low, and there were considerable specific environmental influences for each measure. Future longitudinal studies with language performance and neuroimaging data can further our understanding of genetic and environmental factors involved in the process of cognitive aging.

Dietary Supplement Use in Older People Attending Memory Clinics in Australia

BACKGROUND

Dietary supplement use is common in older adults. There has been limited research in people attending memory clinics.

OBJECTIVES

To explore the use of dietary supplements in older people attending Australian memory clinics.

DESIGN

Cross-sectional analysis of baseline data from the Prospective Research In MEmory clinics (PRIME) study.

PARTICIPANTS

Community-dwelling older people who attended nine memory clinics and had a diagnosis of mild cognitive impairment (MCI) or dementia.

MEASUREMENTS

Dietary supplement was defined as a product that contains one or more: vitamin, mineral, herb or other botanical, amino acid or other dietary substance. Non-prescribed supplement was defined as a supplement that is not usually prescribed by a medical practitioner. Polypharmacy was defined as use of five or more medications.

RESULTS

964 patients, mean age 77.6 years, were included. Dietary supplements were used by 550 (57.1%) patients; 353 (36.6%) used two or more. Non-prescribed supplements were used by 364 (36.8%) patients. Supplement use was associated with older age (OR: 1.12, 95% CI: 1.03-1.21), lower education level (OR: 1.53, 95% CI: 1.01-2.32) and a diagnosis of MCI rather than dementia (OR: 1.52, 95% CI: 1.05-2.21). Potential drug-supplement interactions were identified in 107 (11.1%) patients. Supplement users had increased prevalence of polypharmacy compared to non-users (80.5% vs. 48.1%, p<0.001).

CONCLUSIONS

Dietary supplements, including non-prescribed supplements, were commonly used by people attending memory clinics. Supplement use increased the prevalence of polypharmacy and resulted in potential supplement-drug interactions. Further research is required to assess the clinical outcomes of supplement use.

APOE and BDNF polymorphisms moderate amyloid β-related cognitive decline in preclinical Alzheimer's disease

Accumulation of β-amyloid (Aβ) in the brain is associated with memory decline in healthy individuals as a prelude to Alzheimer's disease (AD). Genetic factors may moderate this decline. We examined the role of apolipoprotein E (ɛ4 carrier[ɛ4(+)], ɛ4 non-carrier[ɛ4(-)]) and brain-derived neurotrophic factor (BDNF(Val/Val), BDNF(Met)) in the extent to which they moderate Aβ-related memory decline. Healthy adults (n=333, Mage=70 years) enrolled in the Australian Imaging, Biomarkers and Lifestyle study underwent Aβ neuroimaging. Neuropsychological assessments were conducted at baseline, 18-, 36- and 54-month follow-ups. Aβ positron emission tomography neuroimaging was used to classify participants as Aβ(-) or Aβ(+). Relative to Aβ(-)ɛ4(-), Aβ(+)ɛ4(+) individuals showed significantly faster rates of cognitive decline over 54 months across all domains (d=0.40-1.22), while Aβ(+)ɛ4(-) individuals showed significantly faster decline only on verbal episodic memory (EM). There were no differences in rates of cognitive change between Aβ(-)ɛ4(-) and Aβ(-)ɛ4(+) groups. Among Aβ(+) individuals, ɛ4(+)/BDNF(Met) participants showed a significantly faster rate of decline on verbal and visual EM, and language over 54 months compared with ɛ4(-)/BDNF(Val/Val) participants (d=0.90-1.02). At least two genetic loci affect the rate of Aβ-related cognitive decline. Aβ(+)ɛ4(+)/BDNF(Met) individuals can expect to show clinically significant memory impairment after 3 years, whereas Aβ(+)ɛ4(+)/BDNF(Val/Val) individuals can expect a similar degree of impairment after 10 years. Little decline over 54 months was observed in the Aβ(-) and Aβ(+) ɛ4(-) groups, irrespective of BDNF status. These data raise important prognostic issues in managing preclinical AD, and should be considered in designing secondary preventative clinical trials.

Genetic contributions to variation in general cognitive function: a meta-analysis of genome-wide association studies in the CHARGE consortium (N=53949)

General cognitive function is substantially heritable across the human life course from adolescence to old age. We investigated the genetic contribution to variation in this important, health- and well-being-related trait in middle-aged and older adults. We conducted a meta-analysis of genome-wide association studies of 31 cohorts (N=53,949) in which the participants had undertaken multiple, diverse cognitive tests. A general cognitive function phenotype was tested for, and created in each cohort by principal component analysis. We report 13 genome-wide significant single-nucleotide polymorphism (SNP) associations in three genomic regions, 6q16.1, 14q12 and 19q13.32 (best SNP and closest gene, respectively: rs10457441, P=3.93 × 10(-9), MIR2113; rs17522122, P=2.55 × 10(-8), AKAP6; rs10119, P=5.67 × 10(-9), APOE/TOMM40). We report one gene-based significant association with the HMGN1 gene located on chromosome 21 (P=1 × 10(-6)). These genes have previously been associated with neuropsychiatric phenotypes. Meta-analysis results are consistent with a polygenic model of inheritance. To estimate SNP-based heritability, the genome-wide complex trait analysis procedure was applied to two large cohorts, the Atherosclerosis Risk in Communities Study (N=6617) and the Health and Retirement Study (N=5976). The proportion of phenotypic variation accounted for by all genotyped common SNPs was 29% (s.e.=5%) and 28% (s.e.=7%), respectively. Using polygenic prediction analysis, ~1.2% of the variance in general cognitive function was predicted in the Generation Scotland cohort (N=5487; P=1.5 × 10(-17)). In hypothesis-driven tests, there was significant association between general cognitive function and four genes previously associated with Alzheimer's disease: TOMM40, APOE, ABCG1 and MEF2C.

Associations between gonadotropins, testosterone and β amyloid in men at risk of Alzheimer's disease

Testosterone and gonadotropins have been associated with cognitive decline in men and the modulation of β amyloid (Aβ) metabolism. The relatively few studies that have investigated whether changes in one or a combination of these hormones influence Aβ levels have focused primarily on plasma Aβ(1-40) and not on the more pathogenic Aβ(1-42). Currently, no study has investigated whether these hormones are associated with an increase in brain amyloid deposition, ante mortem. Through the highly characterised Australian imaging, biomarkers and lifestyle study, we have determined the impact of these hormones on plasma Aβ levels and brain amyloid burden (Pittsburgh compound B (PiB) retention). Spearman's rank correlation and linear regression analysis was carried out across the cohort and within subclassifications. Luteinizing hormone (LH) was the only variable shown, in the total cohort, to have a significant impact on plasma Aβ(1-40) and Aβ(1-42) levels (beta=0.163, P<0.001; beta=0.446, P<0.001). This held in subjective memory complainers (SMC) (Aβ(1-40); beta=0.208, P=0.017; Aβ(1-42); beta=0.215, P=0.017) but was absent in mild cognitive impairment (MCI) and Alzheimer's disease (AD) groups. In SMC, increased frequency of the APOE-ɛ4 allele (beta=0.536, P<0.001) and increasing serum LH levels (beta=0.421, P=0.004) had a significant impact on PiB retention. Whereas in MCI, PiB retention was associated with increased APOE-ɛ4 allele copy number (beta=0.674, P<0.001) and decreasing calculated free testosterone (beta=-0.303, P=0.043). These findings suggest a potential progressive involvement of LH and testosterone in the early preclinical stages of AD. Furthermore, these hormones should be considered while attempting to predict AD at these earliest stages of the disease.

Physical activity and amyloid-β plasma and brain levels: results from the Australian Imaging, Biomarkers and Lifestyle Study of Ageing

Previous studies suggest physical activity improves cognition and lowers Alzheimer's disease (AD) risk. However, key AD pathogenic factors that are thought to be influenced by physical activity, particularly plasma amyloid-β (Aβ) and Aβ brain load, have yet to be thoroughly investigated. The objective of this study was to determine if plasma Aβ and amyloid brain deposition are associated with physical activity levels, and whether these associations differed between carriers and non-carriers of the apolipoprotein E (APOE) ε4 allele. Five-hundred and forty six cognitively intact participants (aged 60-95 years) from the Australian Imaging, Biomarkers and Lifestyle Study of Ageing (AIBL) were included in these analyses. Habitual physical activity levels were measured using the International Physical Activity Questionnaire (IPAQ). Serum insulin, glucose, cholesterol and plasma Aβ levels were measured in fasting blood samples. A subgroup (n=116) underwent (11)C-Pittsburgh compound B (PiB) positron emission tomography (PET) scanning to quantify brain amyloid load. Higher levels of physical activity were associated with higher high density lipoprotein (HDL) (P=0.037), and lower insulin (P<0.001), triglycerides (P=0.019) and Aβ1-42/1-40 ratio (P=0.001). After stratification of the cohort based on APOE ε4 allele carriage, it was evident that only non-carriers received the benefit of reduced plasma Aβ from physical activity. Conversely, lower levels of PiB SUVR (standardised uptake value ratio) were observed in higher exercising APOE ε4 carriers. Lower plasma Aβ1-42/1-40 and brain amyloid was observed in those reporting higher levels of physical activity, consistent with the hypothesis that physical activity may be involved in the modulation of pathogenic changes associated with AD.

Adherence to a Mediterranean diet and Alzheimer's disease risk in an Australian population

The Mediterranean diet (MeDi), due to its correlation with a low morbidity and mortality for many chronic diseases, has been widely recognised as a healthy eating model. We aimed to investigate, in a cross-sectional study, the association between adherence to a MeDi and risk for Alzheimer's disease (AD) and mild cognitive impairment (MCI) in a large, elderly, Australian cohort. Subjects in the Australian Imaging, Biomarkers and Lifestyle Study of Ageing cohort (723 healthy controls (HC), 98 MCI and 149 AD participants) completed the Cancer Council of Victoria Food Frequency Questionnaire. Adherence to the MeDi (0- to 9-point scale with higher scores indicating higher adherence) was the main predictor of AD and MCI status in multinominal logistic regression models that were adjusted for cohort age, sex, country of birth, education, apolipoprotein E genotype, total caloric intake, current smoking status, body mass index, history of diabetes, hypertension, angina, heart attack and stroke. There was a significant difference in adherence to the MeDi between HC and AD subjects (P < 0.001), and in adherence between HC and MCI subjects (P < 0.05). MeDi is associated with change in Mini-Mental State Examination score over an 18-month time period (P < 0.05) in HCs. We conclude that in this Australian cohort, AD and MCI participants had a lower adherence to the MeDi than HC participants.

Plasma apolipoprotein E and Alzheimer disease risk: the AIBL study of aging

OBJECTIVE

There is mounting evidence for the contribution of apoE to the pathophysiology of Alzheimer disease (AD). Studies also indicate that plasma apoE levels may reflect disease status, suggesting that apoE is a potential AD biomarker. However, while some studies of apoE levels in plasma have presented correlations with AD pathology, others have not. Thus, there is a lack of consensus as to the suitability of plasma apoE as an AD biomarker. The major objective of this cross-sectional study was to investigate total plasma apoE as well as levels of the apoE4 form in a large, highly characterized cohort which included both healthy controls and participants with early-stage AD.

METHODS

Total apoE and apoE4 were measured in 1,079 individuals drawn from the highly characterized Australian Imaging, Biomarkers and Lifestyle (AIBL) study. Total and isoform-specific plasma apoE levels were then compared with cerebral Aβ load, as assessed by PET using Pittsburgh compound B (PiB).

RESULTS

Total apoE and apoE4 levels were found to be significantly lower in patients with AD in the entire cohort, and decrease with Aβ load in the PiB-PET subset. ApoE levels were significantly lower among ε4 homozygous individuals. In APOE ε3/ε4 heterozygote carriers, apoE4 levels decrease, indicating that apoE3 levels increase with disease.

CONCLUSION

Analysis of cross-sectional data from the AIBL study indicates that plasma apoE levels are altered in AD and correlate with AD pathology level. The significance of these findings will be determined in the AIBL longitudinal study of aging.

Contrasting perceptions of health professionals and older people in Australia: what constitutes elder abuse?

OBJECTIVES

To explore the perceptions of family carers, older people and health professionals in Australia about what constitutes elder abuse.

METHODS

The Caregiving Scenario Questionnaire (CSQ) was disseminated to health professionals from two metropolitan hospitals, older volunteers and carers of older people with dementia recruited for other studies.

RESULTS

One hundred and twenty health professionals, 361 older people and 89 carers returned the surveys. χ(2) analyses indicated that significantly more health professionals than older people identified locking someone in the house alone all day (χ(2) (2) = 10.20, p = 0.006, Cramer's V = 0.14), restraining someone in a chair (χ(2) (2) = 19.984, p = 0.0005, Cramer's V = 0.19) and hiding medication in food (χ(2) (2) = 8.72, p = 0.013, Cramer's V = 0.13) as abusive. There were no significant differences between healthy volunteer older people and carers in their perceptions of elder abuse. A significant minority (40.8%) of health professionals and over 50% of carers did not identify locking the care recipient alone in the house all day as abusive.

CONCLUSION

In Australia, there is limited consensus between older people, carers and health professionals regarding what constitutes elder abuse. Health professionals were more likely to identify abusive and potentially abusive strategies correctly than carers or healthy older people, but nonetheless between one quarter and two-fifths [correction made here after initial online publication] of health professionals did not identify the abusive strategies.

Predictors of adherence to atypical antipsychotics (risperidone or olanzapine) in older patients with schizophrenia: an open study of 3(1/2) years duration

OBJECTIVE

Although the evidence base for the use of antipsychotics in older people with schizophrenia is generally of low quality, it tends to support the use of atypical antipsychotics. Only limited information regarding longer term adherence to these apparently more effective drugs is available. The aim of this study was to determine predictors of adherence to risperidone or olanzapine in patients over 60.

METHODS

Patients receiving care from old age psychiatrists for their schizophrenia were randomised to treatment with olanzapine or risperidone and were followed for up to 3(1/2) years. Kaplan-Meier curves were generated to assess the univariate effect of randomisation drug on long-term adherence and Cox regression adjusted for baseline variables which may have affected adherence.

RESULTS

In total, 60.6% of the 66 patients in the study were still taking their randomised drug by the end of the interval in which they remained under observation (64.7% olanzapine and 56.3% risperidone). This difference was non-significant. No baseline variable was associated with an increased risk of non-adherence, though the delivery form of pre-randomisation drug (oral or depot) was weakly (p = 0.054) associated with patients originally on depot being less likely to be adherent to an atypical drug.

CONCLUSIONS

Overall adherence with atypical medication was good with almost two-thirds of the patients remaining on their randomisation drug for the interval in which they were under observation. Patients taken off depot were less likely to be adherent but there was no significant difference in adherence between olanzapine and risperidone. Scrutiny of the survival curves suggested that non-adherence is an early event in treatment and patients adherent at 6 months were likely to remain adherent over a longer time period.

Beta-amyloid burden in the temporal neocortex is related to hippocampal atrophy in elderly subjects without dementia

OBJECTIVE

To investigate whether global and regional beta-amyloid (Abeta) burden as measured with 11C Pittsburgh compound B (PIB) PET is associated with hippocampal atrophy characterized using MRI in healthy controls and patients with amnestic mild cognitive impairment (aMCI) or Alzheimer disease (AD).

METHODS

Ninety-two elderly healthy controls, 32 subjects with aMCI, and 35 patients with AD were imaged using 11C-PIB PET and MRI. Hippocampal volume was measured and PIB standardized uptake value ratio was extracted after partial volume correction within 41 regions of interest. Global, regional, and voxel-based correlations between PIB and hippocampal volume were computed for each group.

RESULTS

In healthy control participants with elevated neocortex PIB retention, significant correlation was found between PIB retention in the inferior temporal region and hippocampal volume using both region-based and voxel-based approaches. No correlation was found in any other group.

CONCLUSIONS

The strong correlation between hippocampal atrophy and beta-amyloid (Abeta) burden in the Pittsburgh compound B-positive healthy control group suggests that Abeta deposition in the inferior temporal neocortex is related to hippocampal synaptic and neuronal degeneration.

South Asian strokes: lessons from the St Mary's stroke database

BACKGROUND

South Asians comprise the largest ethnic minority population in the UK. This subgroup is known to have an elevated risk of stroke. However, there is limited data on patterns of cerebrovascular disease and associated risk factors in this population.

AIM

The aim of this study was to analyse differences in stroke subtype and risk factor profile between South Asian and White stroke patients admitted to a central London teaching hospital.

DESIGN

Prospective database of all admissions to the St Mary's Hospital stroke unit.

METHODS

We examined ethnicity, stroke subtype and risk factor profile of consecutive patients admitted to the stroke unit between 8 October 2003 and 14 February 2007.

RESULTS

A total of 811 patients were identified of whom 736 had strokes. Four hundred and ninety-six (67%) occurred in the White subgroup, and 72 (10%) in the Asian subgroup. The South Asian subgroup was significantly younger (65 vs. 73 years in the White subgroup; P < 0.001). They had higher rates of hypertension (age adjusted frequency 87% vs. 64%; P < 0.0001), diabetes (54% vs. 15%; P < 0.0001), and hyperlipidaemia (70% vs. 45%; P = 0.001). There were lower rates of smoking (15% vs. 33%; P < 0.0001).There was a trend towards more lacunar infarcts and less total anterior circulation infarcts in South Asians, although after age adjustment this was not significant at the 5% level.

CONCLUSION

The South Asian subgroup has shown important differences in risk factor profile compared with the White population. The higher frequency of hypertension, diabetes and hyperlipidaemia seen in this subgroup are an important consideration in designing secondary prevention programmes tailored specifically to this community.

Integrated care improves risk-factor modification after stroke: initial results of the Integrated Care for the Reduction of Secondary Stroke model

OBJECTIVE

Despite evidence demonstrating that risk-factor management is effective in reducing recurrent cerebrovascular disease, there are very few structured care programmes for stroke survivors. The aim was to implement and evaluate an integrated care programme in stroke.

METHODS

186 patients with stroke were randomised to either the treatment (integrated care) or control (usual care) group and were followed up over 12 months. The Integrated Care for the Reduction of Secondary Stroke (ICARUSS) model of integrated care involved collaboration between a specialist stroke service, a hospital coordinator and a patient's general practitioner. The primary aim was to promote the management of vascular risk factors through ongoing patient contact and education.

RESULTS

In the 12 months poststroke, systolic blood pressure (sBP) decreased in the treatment group but increased in controls. The group difference was significant, and remained so when age, sex, disability and sBP at discharge were accounted for (p = 0.04). Treatment patients also exhibited better modification of body mass index (p = 0.007) and number of walks taken (p<0.001) than controls. Rankin scores indicated significantly reduced disability in treatment patients relative to controls in the year poststroke (p = 0.003).

CONCLUSIONS

Through an integrated system of education, advice and support to both patient and GP, the ICARUSS model was effective in modifying a variety of vascular risk factors and therefore should decrease the likelihood or recurrent stroke or vascular event.

Antipsychotics, cognitive decline and death in Alzheimer's disease: the London and South-East Region Alzheimer's Disease longitudinal study

The LASER‐AD study provides limited reassurance in relation to the occasional prescription of novel antipsychotics to elderly people with dementia

A comparison of the efficacy and safety of olanzapine and risperidone in the treatment of elderly patients with schizophrenia: an open study of six months duration

BACKGROUND

Following an earlier study in which elderly patients with schizophrenia had their typical antipsychotic medication changed to olanzapine or risperidone, the 61 patients were followed for up to a further six months to see if either treatment was superior in terms of efficacy or side effects.

AIMS

To determine whether either olanzapine or risperidone was superior in terms of efficacy or side effects when treating schizophrenia in late life.

METHODS

Psychiatric symptoms, side effects and quality of life were rated every six weeks for 24 weeks of open label comparative treatment using standard measures. Group differences were examined using analysis of covariance and within-group changes over time were assessed using paired t-tests.

RESULTS

There were 34 olanzapine and 32 risperidone patients who entered the study, but intention to treat data was only available for 61 of the 66 patients. There were no clinical or demographic differences between the groups. Parkinsonism, positive and negative symptoms of schizophrenia improved in both groups both from baseline switch to olanzapine or risperidone and during the six month follow-up after completion of crossover. No significant differences were seen between groups on most measures. However, patients treated with olanzapine showed a significantly greater improvement in quality of life from baseline compared to risperidone patients.

CONCLUSIONS

Both drugs were well tolerated and their use was associated with fewer symptoms of schizophrenia and less adverse effects than were seen when the patients were taking a typical antipsychotic at baseline. Olanzapine appears to have particular benefit with regard to quality of life.

Behavioral and psychological symptoms of dementia in developing countries

BACKGROUND

Little is known about the prevalence of, or associations with behavioral and psychological symptoms of dementia (BPSD) in developing countries.

METHODS

Individuals diagnosed as having dementia according to DSM-IV criteria (mild and moderate cases as defined by the Clinical Dementia Rating scale only), together with their main caregiver, were recruited from 21 centers in 17 developing countries. People with dementia were directly assessed with the Community Screening Interview for Dementia and the Geriatric Mental State Schedule (GMS); GMS data were processed by the AGECAT computer program to yield diagnostic information on 8 psychiatric syndromes. Caregivers answered direct questions about behavioral symptoms of dementia (BSD) and completed the Zarit Burden Inventory.

RESULTS

At least one BSD was reported in 70.9% of the 555 participants. At least one case-level AGECAT psychiatric syndrome (not including the organic syndrome) was exhibited by 49.5% of people with dementia. Depression syndromes (43.8%) were most common followed by anxiety neurosis (14.2%) and schizophreniform/paranoid psychosis (10.9%). Caregivers were more likely to report BSD in people with dementia who were married, younger and better educated. More advanced dementia, poorer functioning and the presence of depression or anxiety were each associated with BSD. BSD, and psychiatric syndromes (anxiety neurosis and schizophreniform/paranoid psychosis) predicted caregiver strain after controlling for cognitive impairment. BPSD are poorly understood, leading to shame and blame.

CONCLUSIONS

BPSD are common among people with dementia in developing countries, though we found marked regional variations. Representative population studies are needed to clarify prevalence and impact, but our research suggests considerable unmet need, with much scope for intervention. Raising awareness of the problem should be the first step.

The impact upon extra-pyramidal side effects, clinical symptoms and quality of life of a switch from conventional to atypical antipsychotics (risperidone or olanzapine) in elderly patients with schizophrenia

BACKGROUND

Atypical antipsychotics are commonly used in the management of schizophrenia in late life with evidence suggesting they induce lower rates of motor disturbance, but have similar efficacy to conventional antipsychotics. Trials in the elderly have been either retrospective, small, of short duration or of a single-arm design.

AIMS

To demonstrate the effects upon motor side-effects, efficacy, safety and quality of life (QOL) of switching elderly patients with schizophrenia from conventional antipsychotics to olanzapine or risperidone.

METHODS

Elderly patients with schizophrenia were randomly allocated to olanzapine or risperidone and followed through an open-label crossover period. Between and within group intention to treat analyses were conducted.

RESULTS

66 patients were randomised (mean age 69.6 [SD +/- 6.2]). Four (11.8%) patients on olanzapine and 8 (26.7%) patients on risperidone failed to complete the crossover because of treatment failure [Odds Ratio (OR) = 2.73[0.73-10.2] p = 0.14]. The mean doses upon completion of switching in each arm were 9.9 mg (SD = 4.2) and 1.7 mg (SD = 1.2) for olanzapine and risperidone respectively. In both arms there was improvement in Parkinsonism, though only olanzapine was associated with a reduction in dyskinetic symptoms. The Brief Psychiatric Rating Scale, Scale for the assessment of Negative Symptoms and Montgomery and Asberg Depression Rating Scale scores all improved through the crossover period in both arms with no between group differences. Treatment with olanzapine was associated with a better response over risperidone on the psychological domain of the World Health Organisation-Quality Of Life [Brief] (WHO-QOL-BREF) scale ( p = 0.02). Patients in the olanzapine arm also demonstrated improvement from baseline in the WHO-QOL-BREF physical, psychological and health satisfaction domains, but risperidone had no effect on any Quality of Life (QOL) measure.

CONCLUSIONS

After switching from a conventional antipsychotic, olanzapine and risperidone were associated with improvement in core symptoms of schizophrenia and motor side effects. Subjects switched to olanzapine were more likely to complete the switching process and show an improvement in psychological QOL.

[Minimizing the risks associated with QTc prolongation in people with schizophrenia. A consensus statement by the Cardiac Safety in Schizophrenia Group]

Schizophrenia is one of the most debilitating mental illnesses, complicated by an increased incidence of suicide amongst patients compared with the general population. A recent report has also demonstrated a 33% increase in -relative risk of death associated with circulatory disease, indicating that the latter may be a more critical factor than either suicide or accidental death in this population. Indeed, the average life expectancy of a person with schizophrenia is currently approximately a decade less than that of the general population. Additionally, it has been shown that in over 50% of people with schizophrenia, there is a reduction in their chance of reaching psychosocial goals. Since the arrival of the first antipsychotic drugs in the middle of the last century, the outlook for patients with schizophrenia has improved markedly. In particular, the introduction of the new generation (atypical) class of antipsychotic agents in the 1980s and 90s has resulted in a significant reduction in the incidence of violent and aggressive episodes in treated patients. A better side-effect profile of these drugs, especially reduced extra pyramidal symptoms (EPS), has resulted in improved patient outcomes and the possibility of good long-term control of the disorder. However, while the introduction of antipsychotic agents has undoubtedly revolutionised the prognosis for patients with schizophrenia, these medications are not without their own problems. One of the concerns to emerge over the last fifteen years is unpredictable, sudden and unexplained death in patients taking antipsychotic drugs. The cause of sudden death in this population is controversial and the role of drugs is not clear. People with schizophrenia also appear to be at higher risk of cardiovascular disease compared with the general population. Many factors may play a role in this including a higher prevalence of smoking, poorer diet, more sedentary lifestyle and a greater likelihood of alcoholism and substance abuse. However, it is possible that the impact of adverse effects on the cardiovascular system related to certain antipsychotic drug use may well increase the prevalence of mortality and morbidity due to cardiovascular events and may also play a significant role in the reduced life expectancy of the patient with schizophrenia. The range of mechanisms whereby antipsychotic drugs can influence cardiovascular function is very broad and includes: receptor blockade; conduction disturbance (eg bundle branch block); delayed ventricular repolarisation (prolonged QTc interval); left ventricular dysfunction; sinus node abnormalities; myocarditis; postural hypotension; polydipsia-hyponatremia syndrome; weight gain; glucose intolerance. Of these, QTc interval prolongation, with the risk of progression to the potentially fatal ventricular tachyarrhythmia Torsades de Pointes (TdP), is of particular concern as this arrhythmia is unpredictable and difficult to manage. Coupled with these clinical concerns are regulatory issues regarding several compounds that have received warnings or been withdrawn from the market. Recently, there has been no clear guidance for psychiatrists regarding QTc interval prolongation and TdP. This document seeks: 1) to explore drug-induced ventricular arrhythmias with particular emphasis on QTc interval prolongation as a warning of increased vulnerability, 2) to provide guidelines on the therapeutic management of the patient with schizophrenia to minimize the risk of iatrogenic cardiotoxicity. Several guidance documents have previously been published in this area including the report published by the UK Working Group of the Royal College of Psychiatrists' Psychopharmacology Sub-Group in 1997, and the policy document on the potential for QTc prolongation and proarrhythmia by non-antiarrhythmic drugs published in June 1999 under the auspices of the European Society of Cardiology. This document seeks to supplement currently published guidelines.

An examination of pain perception and cerebral event-related potentials following carbon dioxide laser stimulation in patients with Alzheimer's disease and age-matched control volunteers

BACKGROUND

Pain perception is known to depend on integrated cognitive processing. Alzheimer's disease affects 5% to 10% of older adults, but the impact of this disease on pain sensitivity and report has yet to be fully investigated.

AIM OF INVESTIGATION

The present study examined pain threshold, the reliability of pain report and the central nervous system processing of noxious input, as indexed by cerebral event-related potentials (CERP).

METHODS

Carbon dioxide laser detection and heat pain thresholds were determined on the hand dorsum of 15 healthy older adults (Mini-Mental State Examination [MMSE] score 29.9 +/- 0.3) and 15 persons with cognitive impairment (MMSE score 12.7 +/- 6.1). Using an array of 15 silver/silver chloride scalp electrodes, the CERP and subjective rating of stimulus intensity were recorded after fixed intensity, 25 W laser stimuli.

RESULTS

Compared with age-matched controls, the detection threshold for just noticeable sensation was significantly increased in elderly adults suffering from Alzheimer's disease. There was no difference in pain threshold intensity between persons with cognitive impairment and controls, although the former group was less reliable in reporting detection and pain threshold sensations. The subjective rating of a 25 W stimulus was virtually identical in both groups, and the amplitude of the major CERP component (P400) was similar; however, cognitively impaired adults exhibited a significant increase in the latency of the P400 response.

CONCLUSIONS

The present findings indicate that pain perception in response to an acute heat pain stimulus is not diminished in older persons with cognitive impairment. Patients with Alzheimer's disease may be slightly less reliable in threshold pain report, although the subjective rating of evoked pain and the level of poststimulus cortical activation following noxious stimulation were found to be similar to those of controls. A longer latency of the CERP may suggest slower cortical processing of nociceptive input by persons with Alzheimer's disease.

Pharmacological treatment of cognitive deficits in Alzheimer's disease

Clinical trials and independent reviews support the use of cholinesterase inhibitors for treating the symptoms of patients with mild to moderate Alzheimer's disease (AD). Before initiating cholinesterase inhibitor therapy, patients should be thoroughly assessed, and the diagnosis confirmed, preferably by a specialist. Compliance with cholinesterase inhibitor therapy should be monitored and the response (in global, cognitive, functional and behavioural domains) reassessed after 2-3 months of treatment. Vitamin E may be protective against AD, and therapy with 1000 IU twice daily may be considered. There is insufficient evidence to support the use of other antioxidant agents, anti-inflammatory agents, monoamine oxidase B inhibitors, folate/homocysteine or antihypertensive drugs in patients with AD, or hormone replacement therapy in affected women.

Combined magnetic resonance imaging and single-photon emission tomography scanning in the discrimination of Alzheimer's disease from age-matched controls

OBJECTIVE

To compare the utility of temporal lobe magnetic resonance imaging (MRI) and single-photon emission tomography (SPET) scanning in discriminating between subjects with Alzheimer's disease (AD) and age-matched controls.

METHODS

Thirty subjects with NINCDS-ADRDA AD (23 probable AD, 5 possible AD, 2 definite AD) and 22 age- and sex-matched controls underwent T1-weighted coronal MRI scanning (0.3 T) and technetium 99m-HMPAO SPET scanning. MRI scans were analyzed using a digitizer system with volumes of hippocampus, amygdala, entorhinal cortex, parahippocampal gyrus, and whole cerebral cortex calculated. From SPET scans, regional cerebral blood flow (rCBF) was assessed in anterior and posterior frontal, parietal, occipital, and mesial temporal cortex using a region of interest analysis with the cerebellum as a reference area.

RESULTS

Using MRI, the areas that best separated groups were left hippocampal and left amygdala volume, resulting in correct classification (patient vs. control) in 79% of cases (sensitivity 77%, specificity 82%). Exactly the same proportion of subjects were correctly classified by SPET, with the most discriminating rCBF changes being left parietal and right posterior frontal. Combining information from both scans improved the proportion of correctly classified subjects in a discriminant function to 90% (sensitivity 93%, specificity 86%; only 2 AD and 3 controls misclassified). All AD subjects had abnormalities on MRI and/or SPET (sensitivity for combined examinations 100%), while abnormalities on both MRI and SPET had a positive predictive value of 100% for dementia (including the detection of one control subject who later had dementia). Significant correlations between MRI and SPET measures were seen in control subjects but not in patients.

CONCLUSION

Both 0.3 T MRI and single rotating gamma camera SPET were equally useful in separating AD subjects from age-matched controls, although the combination of both significantly enhanced discrimination. In particular, all AD subjects had abnormalities on either MRI or SPET and both techniques may have an important role in assisting with clinical diagnosis, though replication in other centers and examination of differentiation of AD from other causes of dementia need to be examined.

Hyponatraemia and selective serotonin re-uptake inhibitors in elderly patients

Hyponatraemia (serum sodium arbitrarily defined as less than 135 mmol/L) is an increasingly recognised adverse effect of selective serotonin re-uptake inhibitors (SSRIs). Its precise prevalence and incidence in the elderly are hard to determine because of confounding factors including other prescribed medications and medical conditions. Although hyponatraemia has been reported with all SSRIs and venlafaxine, most studies are small, retrospective, limited by confounding variables or are individual case reports. The risk of developing hyponatraemia while on an SSRI seems to increase with age, female, sex, previous history of hyponatraemia and the concomitant use of other medications known to include hyponatraemia. The sodium concentrations of most patients with SSRI associated hyponatraemia return to normal within days to weeks of SSRI withdrawal. A few cases of SSRI rechallenge indicate that hyponatraemia may sometimes be a transient effect with tolerance developing over time. There is an urgent need for controlled, rigorous studies to confirm the extent of the association between SSRIs and hyponatraemia. Older drugs such as tricyclic antidepressants also need systematic study. It remains quite unclear whether any specific SSRI or venlafaxine has a stronger association with hyponatraemia than any other antidepressant drug.

Structural neuroimaging studies in late-life depression: a review

Which patients presenting with depression in late life will progress to a dementia syndrome has been an important research question in recent times. In this paper we review selectively structural neuroimaging investigations of late-life depression (LLD) that have been performed over the past two decades. These studies indicate that there are neuroimaging changes commonly observed in LLD patients when compared to normal controls. Findings include ventricular enlargement and sulcal widening, and reduction in volume size of frontal lobes, hippocampus and caudate nucleus. White matter lesions are more common in depressed subjects and tend to be more severe. Some studies report these changes to be more pronounced in patients who present with late-onset depression (LOD) but this has been contradicted by other studies. Preliminary work suggests that these changes may be associated with a poor prognosis but there is a dearth of systematic, well-controlled longitudinal studies.

Equity of access to a memory clinic in Melbourne? Non-English speaking background attenders are more severely demented and have increased rates of psychiatric disorders

OBJECTIVES

The aim of this study was to compare demographic and clinical features of patients from Non-English Speaking Background (NESB) with those from English Speaking Background (ESB) who attended a memory clinic in Melbourne, Australia.

METHODS

Data on 556 consecutive patients attending the memory clinic were analysed retrospectively. All patients were assessed by a geriatrician (Italian speaking) or psychogeriatrician with the aid of Cambridge Examination for Mental Disorders in the Elderly (CAMDEX) interview schedule. Patients were classified into the categories of dementia, functional psychiatric disorder (including depression), cognitive impairment other than dementia and normal, using ICD 10 criteria. Severity of dementia was determined using the Clinical Dementia Rating scale. Demographic information and use of community services were also documented.

RESULTS

Of those seen, 148 (28.8%) were of NESB, the majority Italian (69, 12.4%). Patients of NESB were younger (p = 0.001), less educated (p = 0.001) and less likely to live alone (p = 0.009) compared to persons of ESB. Those of NESB were more likely present with a functional psychiatric disorder (particularly depression) or normal cognition (p = 0.001). Patients of NESB with dementia presented at a later stage of their disease as determined by CDR (p = 0.003). Those of NESB scored significantly lower (more impaired) on CAMCOG in all patients seen (including normal and psychiatric groups) (p = 0.02).

CONCLUSIONS

The clinical and demographic features of people of NESB referred to a memory clinic in Melbourne, Australia, differ from their ESB counterparts, with specific groups being under represented. This has implications for equity of assessment, service provision and utilisation for those of ethnically diverse backgrounds.

Characteristics of aggressive subjects in Australian (Melbourne) nursing homes

BACKGROUND

Aggressive behavior is common in nursing homes for the elderly. It causes distress to carers and can lead to hospitalization, overmedication, and physical restraint.

METHOD

A 6-month prospective study examining the characteristics of aggressive subjects in 11 nursing homes in Melbourne using validated, reliable instruments.

RESULTS

During the study, 121 and 143 subjects were rated aggressive on the Rating Scale for Aggressive Behavior in the Elderly and the Staff Observation Aggression Scale, respectively. Aggressive behavior was associated with younger age, men, subsequent mortality, and prescription of psychotropic drugs including neuroleptics, antidepressants, and benzodiazepines.

CONCLUSIONS

Educational programs in the use of psychotropic drugs directed at staff involved in the care of nursing home residents may be of value because these drugs have modest efficacy, have significant side effects, and may simply sedate the patient rather than treat aggressive behavior.

Effects of the nicotinic antagonist mecamylamine on inspection time

RATIONALE

Several lines of evidence suggest that nicotinic acetylcholine receptors (nAchRs) are involved in speed of information processing, and inspection time appears to be particularly sensitive to nicotinic manipulation.

OBJECTIVE

The present study sought to examine the effects of the nAchR antagonist mecamylamine on inspection time. Furthermore, the extent to which the anticholinesterase donepezil would reverse the effects of mecamylamine on inspection time was also examined.

METHODS

A double-blind, repeated measures design was employed. Subjects (n = 6) received placebo, mecamylamine (20 mg PO) or mecamylamine (20 mg PO) and donepezil (5 mg PO). Inspection time and physiological measures were then assessed.

RESULTS

The mecamylamine condition and the mecamylamine and donepezil condition were associated with an increase in heart rate, when compared to the placebo condition. There was a significant slowing of inspection time in the mecamylamine condition; compared to placebo, which was partly reversed by donepezil.

CONCLUSIONS

The slowing of inspection time following mecamylamine is consistent with the role of nAchRs in speed of information processing, and add to the evidence that IT may in part index nAchR system integrity.

Novel Leu723Pro amyloid precursor protein mutation increases amyloid beta42(43) peptide levels and induces apoptosis

A novel missense mutation, Leu723Pro, in the amyloid precursor protein (APP) gene was discovered in an early-onset Alzheimer's disease family. Expression of L723P mutant APP complementary DNA in CHO cells resulted in a 1.4- to 1.9-fold increased production of the 42(43)-amino acid length amyloid beta peptide compared with the wild-type sequence and was capable of causing apoptosis. The mutation is predicted to alter the luminal transmembrane length and helical arrangement of the APP molecule and thus affect the gamma-secretase cleavage site.

Do memory clinics improve the quality of life of carers? A randomized pilot trial

OBJECTIVE

To determine the effects of attendance at a memory clinic on the psychosocial health of carers.

DESIGN

Randomized control trial.

PARTICIPANTS

Fifty community dwelling subjects with mild to moderate dementia and their carers.

MAIN OUTCOME MEASURES

Carer burden, psychological morbidity and psychosocial health related quality of life at 6 and 12 months post intervention.

MAIN RESULTS

There was significant improvement in psychosocial health related quality of life of carers as measured by the psychosocial domain of the Functional Limitation Profile (FLP) at 6 months (p < 0.01), including improvement in the subgroups of alertness behaviour (p < 0.05) and social interaction (p < 0.01), after adjustment for age of subject and baseline scores. The improvement in social interaction was maintained at 12 months (p < 0.05). There was no significant difference in carer psychological morbidity (General Health Questionnaire), carer burden (Zarit family interview) or carer knowledge of dementia (Dementia Knowledge Test) at 6 or 12 months, between groups.

CONCLUSIONS

These results demonstrate improved psychosocial health related quality of life for carers of those with mild to moderate cognitive impairment attending a memory clinic. Further research in this area is indicated, comparing memory clinic intervention with alternative support.

The Even Briefer Assessment Scale for Depression (EBAS DEP): its suitability for the elderly in geriatric care in English- and German-speaking countries

OBJECTIVES

To determine the psychometric properties of the Even Briefer Assessment Scale for Depression (EBAS DEP) developed by Allen et al. (1994) among samples of the German elderly and compare the results with those from English-speaking countries.

DESIGN

Depression scale scores from elderly persons in residential and gerontopsychiatric care were assessed for internal consistency using Cronbach's alpha and validity (Feighner Criteria of Depression and Center for Epidemiologic Studies Depression Scale).

SUBJECTS

Eight hundred and fifty-two elderly persons aged 65 years and over, in residential and gerontopsychiatric care.

MATERIALS

The eight-item Even Briefer Assessment Scale for Depression (EBAS DEP) derived from the 21-item Brief Assessment Scale (BAS DEP).

RESULTS

The analysis of the reliability of the German EBAS DEP yielded, as did that of the English version, a satisfactorily high internal consistency (0. 73 and higher). Based on a subset of 71 subjects, the validity of the scale was tested by independent psychiatric experts using the Feighner Criteria of Depression. The EBAS DEP (cutoff 3/4) had a sensitivity and specificity for a diagnosis of depression of 93.3% and 85.3%, respectively. Similar results were reported by Allen et al., but at a lower cutoff (2/3). In agreement with the English findings, the receiver operating curve (ROC) statistics revealed that the EBAS DEP is a screening instrument which is as efficient as the longer BAS DEP.

CONCLUSION

The EBAS DEP is an instrument well suited for use in screening the depressed elderly in different care settings in English- and German-speaking countries.

Severe deep white matter lesions and outcome in elderly patients with major depressive disorder: follow up study

OBJECTIVE

To determine the difference in outcome among elderly people with major depression who do and do not have severe white matter lesions on magnetic resonance imaging.

DESIGN

Follow up study.

SETTING

Two psychiatric and two general hospitals in Melbourne, Australia.

SUBJECTS

60 depressed subjects aged over 55 referred to hospital psychiatric services with major depressive disorder meeting American Psychiatric Association (DSM-IIIR) criteria.

MAIN OUTCOME MEASURE

Proportion with good outcome as determined by full recovery from initial illness and no evidence of depressive relapse or cognitive decline during follow up among those with and without lesions.

RESULTS

Mean (SD) follow up was 31.9 (9.9) months. Survival analysis showed a significant effect of severe lesions on time to poor outcome (P=0.04), with median survival 136 days in those with severe lesions compared with 315 days in those without.

CONCLUSION

Severe white matter change on magnetic resonance imaging is associated with poor outcome in elderly depressed subjects.