Quantifying fluctuation in dementia with Lewy bodies, Alzheimer's disease, and vascular dementia

BACKGROUND

Case reports and clinical observations suggest that fluctuating cognition (FC) is common in the major dementias, particularly dementia with Lewy bodies (DLB), where it is one of three core clinical diagnostic features.

OBJECTIVES

To examine the frequency, characteristics, and diagnostic utility of FC in dementia using clinical, attentional, and EEG markers.

METHOD

- A total of 155 subjects (61 with AD, 37 with DLB, 22 with vascular dementia [VaD], 35 elderly controls) received clinical evaluation for FC using a semiquantified measure applied by experienced clinicians and 90-second cognitive choice reaction time (CRT) and vigilance reaction time (VIGRT) trials. Forty subjects also received an evaluation of mean EEG frequency across 90 seconds.

RESULTS

Patients with DLB had a greater prevalence and severity of FC than did patients with AD or VaD rated using clinical, attentional, and EEG measures. The 90-second cognitive and EEG trials demonstrated that FC occurs on a second-to-second basis in patients with DLB. Patients with VaD had a higher prevalence of FC than did those with AD, although the profile of FC was different from that expressed by DLB cases. Optimal cutoff values on the clinical scale achieved good discrimination between the dementia groups (sensitivity 81%, specificity 92%, DLB versus AD; sensitivity 81%, specificity 82%, DLB versus VaD; sensitivity 64%, specificity 77%, VaD versus AD).

CONCLUSION

Standardized assessment methods demonstrate that FC is significantly more common and severe in DLB than in other major dementias. The periodicity of FC is different in DLB and VaD cases, with important implications for the underlying causal mechanisms and for differential diagnosis.

Cognitive deficit induced by acute tryptophan depletion in patients with Alzheimer's disease

OBJECTIVE

The study assessed the effects on global cognitive function and mood of a reduction of brain serotonin by means of acute tryptophan depletion in 16 patients with dementia of the Alzheimer type and in 16 cognitively intact comparison subjects.

METHOD

In a double-blind, crossover design, subjects received a tryptophan-free amino acid drink to induce acute tryptophan depletion and, on a separate occasion, a placebo drink containing a balanced mixture of amino acids. On each occasion, ratings of depressed mood were made at baseline and 4 and 7 hours later, and the Modified Mini-Mental State was administered at baseline and 4 hours later.

RESULTS

Patients with dementia of the Alzheimer type had a significantly lower mean score on the Modified Mini-Mental State after acute tryptophan depletion than after receiving placebo. The comparison group showed no difference in mean score on the Modified Mini-Mental State after acute tryptophan depletion and after receiving placebo. No significant changes in mood were found in either group.

CONCLUSIONS

Acute tryptophan depletion significantly impaired cognitive function in patients with dementia of the Alzheimer type. Compromised serotonergic function, in combination with cholinergic deficit, may make an important contribution to cognitive decline in dementia of the Alzheimer type.

Prospective validation of consensus criteria for the diagnosis of dementia with Lewy bodies

OBJECTIVE

To determine the validity of a clinical diagnosis of probable or possible dementia with Lewy bodies (DLB) made using International Consensus criteria.

BACKGROUND

Validation studies based on retrospective chart reviews of autopsy-confirmed cases have suggested that diagnostic specificity for DLB is acceptable but case detection rates as low as 0.22 have been suggested.

METHODS

We evaluated the first 50 cases reaching neuropathologic autopsy in a cohort to which Consensus clinical diagnostic criteria for DLB, National Institute for Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria for AD, and National Institute of Neurological Disorders and Stroke-Association Internationale pour la Recherche et l'Enseignement en Neurosciences criteria for vascular dementia (VaD) had been prospectively applied.

RESULTS

Twenty-six clinical diagnoses of DLB, 19 of AD, and 5 of VaD were made. At autopsy, 29 DLB cases, 15 AD, 5 VaD, and 1 progressive supranuclear palsy were identified. The sensitivity and specificity of a clinical diagnosis of probable DLB in this sample were 0.83 and 0.95. Of the five cases receiving a false-negative diagnosis of DLB, significant fluctuation was present in four but visual hallucinations and spontaneous motor features of parkinsonism were generally absent. Thirty-one percent of the DLB cases had additional vascular pathology and in two cases this contributed to a misdiagnosis of VaD. No correlations were found between the distribution of Lewy bodies and clinical features.

CONCLUSION

The Consensus criteria for DLB performed as well in this prospective study as those for AD and VaD, with a diagnostic sensitivity substantially higher than that reported by previous retrospective studies. DLB occurs in the absence of extrapyramidal features and in the presence of comorbid cerebrovascular disease. Fluctuation is an important diagnostic indicator, reliable measures of which need to be developed further.

Lack of association of the alpha2-macroglobulin locus on chromosome 12 in AD

OBJECTIVE

Analysis of AD has revealed that the apolipoprotein E locus (APOE) cannot account for all of the genetic risk associated with AD. Whole genome scanning in AD families suggests that a chromosome 12 locus may contribute significantly to disease development. The alpha2-macroglobulin gene (A2M) has been suggested as a candidate locus for AD based on analysis of familial AD.

METHOD

We determined, in 195 neuropathologically verified AD cases and 107 age-matched control subjects, the association of two common polymorphisms in A2M (a pentanucleotide deletion 5' to the bait domain exon, and a valine-1000-isoleucine polymorphism in the thiolester site of the protein).

RESULTS

Evidence was observed for linkage disequilibrium between the deletion and Ile1000 polymorphisms. No evidence was observed for an association between the thiolester polymorphism and AD alone or when accounting for the APOE-epsilon4 allele. No alteration in the frequency of the bait domain deletion was observed, although a small excess (4%) of deletion homozygotes was found in the AD group, which were absent in the control population.

CONCLUSIONS

The A2M deletion polymorphism at most accounts for a small fraction of the genetic contribution toward AD, and this is small compared with APOE. Furthermore, reverse transcriptase PCR of A2M RNA from the brains of patients homozygous for the deletion polymorphism showed that the bait domain exon still is present in the RNA. This suggests that the A2M deletion polymorphism may be nonfunctional and that the chromosome 12 AD locus is situated elsewhere.

Nicotine binding in human striatum: elevation in schizophrenia and reductions in dementia with Lewy bodies, Parkinson's disease and Alzheimer's disease and in relation to neuroleptic medication

Striatal nicotinic acetylcholine receptors with high affinity for nicotinic agonists are involved with the release of a number of neurotransmitters, including dopamine. Previous findings as to whether these receptors are changed in Parkinson's disease and Alzheimer's disease are inconsistent and no previous investigations have focused on these receptors in dementia with Lewy bodies and schizophrenia, which are also associated with disorders of movement. The present autoradiographic study of striatal [3H]nicotine binding in Alzheimer's and Parkinson's diseases, dementia with Lewy bodies and schizophrenia was conducted with particular reference to the potentially confounding variables of tobacco use and neuroleptic medication. [3H]Nicotine binding in both dorsal and ventral caudate and putamen was significantly reduced in Parkinson's disease (43-67%, n=13), Alzheimer's disease (29-37%, n=13) and dementia with Lewy bodies (50-61%, n=20) compared to age-matched controls (n=42). Although tobacco use in the control group was associated with increased [3H]nicotine binding (21-38%), and neuroleptic treatment in dementia with Lewy bodies and Alzheimer's disease was associated with reduced [3H]nicotine binding (up to 29%), differences between neurodegenerative disease groups and controls persisted in subgroups of Alzheimer's disease cases (26-33%, n=6, in the ventral striatum) and dementia with Lewy body cases (30-49%, n=7, in both dorsal and ventral striatum) who had received no neuroleptic medication compared to controls who had not smoked (n=10). In contrast, striatal [3H]nicotine binding in a group of elderly (56-85 years) chronically medicated individuals with schizophrenia (n=6) was elevated compared with the entire control group (48-78%, n=42) and with a subgroup that had smoked (24-49%, n=8). The changes observed in [3H]nicotine binding are likely to reflect the presence of these receptors on multiple sites within the striatum, which may be differentially modulated in the different diseases. Further study is warranted to explore which nicotinic receptor subunits and which neuronal compartments are involved in the changes in [3H]nicotine binding reported, to aid development of potential nicotinic receptor therapy.

The prevalence, assessment and associations of falls in dementia with Lewy bodies and Alzheimer's disease

Falls were assessed for 3 months using a daily fall diary in 65 (30 dementia with Lewy bodies, DLB; 35 Alzheimer's disease, AD) dementia patients from a case register, diagnosed using operationalised clinical criteria, with established accuracy against post-mortem. Multiple falls (>5) occurred in 37% of DLB patients and 6% of those with AD, often resulting in injury. None of the standard risk assessment tools identified fallers, but they did identify multiple fallers. More detailed evaluation methods examining gait patterns, sway and neurovascular instability were not helpful. Multiple falls were associated with DLB, parkinsonism, previous falls, greater impairment of activities of daily living and older age. Falls are particularly common in DLB sufferers and may aid diagnosis. Treatment studies evaluating fall reduction strategies are a priority.

Simple standardised neuropsychological assessments aid in the differential diagnosis of dementia with Lewy bodies from Alzheimer's disease and vascular dementia

Consecutive patients from a dementia case register received a standardised evaluation which incorporated a neuropsychological assessment with the Cambridge Assessment for disorders in the elderly (CAMCOG). Operationalised clinical diagnoses were made (consensus criteria for dementia with Lewy bodies, DLB; NINCDS- ADRDA for Alzheimer's disease, AD, NINCDS AIRENS for vascular dementia, VaD). Two-hundred and twenty-eight patients were studied (DLB 54, AD102, VaD 72). DLB patients had significantly better performance on recent memory than AD patients, but more impaired visuospatial praxis. DLB patients also had significantly better recent memory than those with VaD. Optimal cut-off points for the recent memory:praxis ratio achieved good discrimination between DLB and both other dementias.

A prospective study of dementia with Lewy bodies

BACKGROUND

little is known about the longitudinal course of dementia with Lewy bodies (DLB) and how this differs from Alzheimer's disease (AD).

METHOD

standardized baseline and annual assessments of cognitive and non-cognitive symptoms are reported in a cohort of 72 patients with DLB or AD. AD was diagnosed using the NINCDS ADRDA criteria and DLB was diagnosed with the criteria of McKeith et al. Cognitive assessment was undertaken using the MMSE schedule and operationalized definitions were used to diagnose non-cognitive symptoms.

RESULTS

42 patients with DLB and 30 patients with AD were assessed. Of the 19 on whom post mortem examinations have been performed, 18 (95%) have had the clinical diagnosis confirmed. DLB patients were significantly more likely to experience visual hallucinations, disturbances of consciousness and parkinsonism at both baseline and at annual assessments. Of DLB patients exposed to neuroleptics, 33% developed sensitivity reactions. The magnitude and pattern of cognitive decline was similar in both groups.

CONCLUSION

the importance of the core features highlighted in the newly proposed consensus DLB criteria is supported. These features appear to be stable over time.

Eating disorders in dementia

OBJECTIVES

To examine the prevalence and associations of altered eating patterns in dementia sufferers.

DESIGN

Prospective cohort study.

SETTING

Psychiatric services and a memory clinic.

SAMPLE

124 patients with DSM-III-R dementia.

MEASURES

The Geriatric Mental State Schedule, the History and Aetiology Schedule, the Cornell Depression Scale and the CAMCOG. Additional standardized questions were asked about eating patterns in the month prior to the study.

RESULTS

Information concerning eating patterns was obtained from 105 of the 124 patients: 21% had increased food consumption, 22.1% had decreased food consumption, 2.9% tried to eat inedible substances, 11.4% had an increased preference for sweet things, 7.6% became more fussy about their food choices and 4.8% became less fussy. Decreased food consumption was significantly associated with less severe cognitive impairment and was related to RDC major depression in some patients. An increased preference for sweet things showed an association with a diagnosis of Alzheimer's disease. Increased food consumption was probably heterogeneous. Neither increased food consumption nor an increased preference for sweet foods was associated with the severity of cognitive impairment.

CONCLUSION

Altered eating patterns are common in dementia sufferers.

Sexual relationships in married dementia sufferers

OBJECTIVE

To determine the proportion of couples, one of whom suffers from dementia, continuing with a sexual relationship, their level of satisfaction with their sexual relationship and the associations of remaining sexually active.

DESIGN

A survey of married couples enrolled in a prospective dementia study.

SETTING

Psychiatric services and a memory clinic.

SAMPLE

The partners of 47 married patients with mild to moderate dementia.

MEASURES

The assessment included the GMS/HAS/SDS package, the Marital Intimacy Scale (with some additional questions regarding sexual relations), the CAMCOG, the Carers Stress Scale, the Cornell Depression Scale and the Burns Symptom Checklist. Dementia was diagnosed according to DSM-III-R, McKhann, McKeith, Hachinski and HAS AGECAT criteria.

RESULTS

Forty partners completed the study. Nine (22.5%) continued to have a sexual relationship, all of whom were satisfied with the situation. Twelve (38.7%) of the carers who were not sexually active were dissatisfied with the absence of a sexual relationship. There was a trend for male carers to be more likely to be involved in a continuing sexual relationship. Dissatisfaction with the absence of a sexual relationship was significantly associated with a diagnosis of vascular dementia in the patient and showed a trend towards an association with younger patient age.

CONCLUSIONS

Nearly a quarter of married dementia sufferers are involved in a continuing sexual relationship, emphasizing the importance of further research in this area.

A one-year follow-up study of depression in dementia sufferers

BACKGROUND

Little data are available about the course or incidence of depression in dementia sufferers.

METHOD

Monthly follow-up data over one year is reported regarding depression in a cohort of 124 dementia sufferers. Dementia was diagnosed according to DSM-III-R criteria. Depression was assessed with the Cornell Depression Scale and diagnosed according to RDC criteria. Cognitive functioning was assessed with the CAMCOG:

RESULTS

Eighty-nine of the 124 patients completed the follow-up. The annual incidence rates of RDC major depression and RDC minor depression were 10.6% and 29.8%, respectively. Twenty per cent of patients with depression experienced these symptoms for six months or longer. Patients with vascular dementia were significantly more likely to experience three or more months of depression than patients with other dementias. RDC minor depression was highly persistent among 23.8% of sufferers.

CONCLUSION

Depression is persistent in patients with vascular dementia. Some patients with minor depression have a dysthymia-like disorder.

The aetiology of depression in the carers of dementia sufferers

OBJECTIVE

To examine the associations of depression in the carers of dementia sufferers, diagnosed on the basis of a semistructured interview.

DESIGN

Case control study.

SETTING

Referrals to clinical services.

SUBJECTS

The informal carers of 109 dementia sufferers, 32 with depression and 77 without.

MEASURES

Carers were interviewed using the Geriatric Mental State Schedule. The diagnosis of depression was made according to Research Diagnostic Criteria. Instruments used to assess associations included Carers' Stress Scale, Marital Intimacy Scale, Cornell Depression Scale and CAMCOG Schedule.

RESULTS

Only increasing age was significantly associated with depression in the overall group of carers. The severity of cognitive impairment was significantly associated with depression in carers who lived with a dementia sufferer and a low level of premorbid marital intimacy was significantly associated with depression amongst carers who were marital partners.

CONCLUSION

Few factors are clearly associated with depression in the carers of dementia sufferers. The pattern of associations was, however, different for carers in different situations.

Classification of psychotic symptoms in dementia sufferers

Little attention has been payed to the classification of psychotic symptoms in dementia sufferers. This article compares the etiology of delusions, visual hallucinations and delusional misidentification and examines the value of factors generated from principal components analysis as a possible classificatory system in a group of 125 patients with DSM-III-R dementia in contact with clinical services who were prospectively evaluated using standardized instruments to describe in detail individual psychotic symptoms. The assessment also included the Geriatric Mental State Schedule, the History and Aetiology Schedule and the CAMCOG. Delusions and visual hallucinations had a distinct cognitive profile as did delusions and delusional misidentification, although there was an overlap between visual hallucinations and delusional misidentification. Four factors were generated from principal components analysis. Three of these closely mirrored the 3 symptom groups delusions, visual hallucinations and delusional misidentification, although the phantom-boarder delusion was correlated with the visual hallucination factor and not delusional misidentification. The fourth factor included visual hallucinations of relatives and delusions that relatives were in the house. This factor was strongly inversely associated with emotional distress and could perhaps best be seen as a comfort phenomena. The pattern of cognitive deficits and etiological associations of each of the factors were independent of one another, supporting the notion that it is useful to consider them as separate entities.

Post-traumatic stress disorder (PTSD) after childbirth

BACKGROUND

There has been discussion about the possible occurrence of post-traumatic stress disorder (PTSD) in mothers after difficult childbirth.

METHOD

Four cases with a symptom profile suggestive of PTSD commencing within 48 hours of childbirth are presented.

RESULTS

The PTSD was in each case associated with the delivery. In each case, there was an associated depressive illness. All four had persistent disorders, and two had difficulties with mother/infant attachment.

CONCLUSION

As confirmed by other reports, the prevalence of PTSD associated with childbirth is a matter of concern.

Prevalence of postnatal psychiatric morbidity in mothers and fathers

In the first study to systematically examine postnatal depression in fathers, we examined depression in 200 postnatal couples, using a two-stage design. The prevalence of depression ascertained by the 13-item Edinburgh Postnatal Depression Scale (EPDS), using a cut-off score for 'caseness' of 13 or more in an unselected postnatal sample, was 27.5% in mothers at six weeks postpartum, 25.7% in mothers at six months postpartum, 9.0% in fathers at six weeks postpartum, and 5.4% in fathers at six months postpartum. The prevalence did not differ significantly in either mothers or fathers from a control group of parents with children between three and five years of age. As expected, mothers had a significantly higher prevalence of psychiatric 'caseness' at both six weeks and six months postpartum than fathers. Fathers were significantly more likely to be cases if their partners were also cases. The hypothesis that different aetiological factors would be important in brief and persistent disorders in mothers was upheld.

Prevalence, symptom profile, and aetiology of depression in dementia sufferers

Ninety-two consecutive attenders at a day hospital for the assessment of dementia were assessed using the CAMDEX schedule. The prevalence of depression in the 58 dementia sufferers who fulfilled the entry criteria for the study was 24.1%. The prevalence of depression was similar in patients with senile dementia of Alzheimer's type and those with vascular dementia. Patients with minimal dementia were significantly more likely to suffer from depression than those with mild or moderate dementia but there was no significant association with insight. The symptom profile of patients with minimal dementia was significantly correlated to that of patients with mild dementia and both were similar to the symptom profiles previously described amongst the elderly with functional depression. Physical illness was not associated with depression in the current sample. The implications of the findings are discussed.

Eating disorder in a 6-year-old Asian girl with ethyl malonic adipic aciduria

Accurate data are not available for the prevalence of eating disorders amongst the Asian population in Britain. Only a handful of cases have been reported in the literature [Bhadrinath (1990). British Journal of Psychiatry, 156, 565-568.] suggested that it is an uncommon phenomenon despite Dolan's recent finding [Dolan, Lacey, & Evans (1990). British Journal of Psychiatry, 157, 523-528.] that there were elevated Eating Attitudes Test (EAT) scores in a sample of young Asian adults compared with Caucasians. We report a case of an Asian girl with a rare inborn error of metabolism and an eating disorder.

Deliberate self-poisoning in Asian and Caucasian 12-15-year-olds

The mean annual rates of hospital admission for deliberate self-poisoning were calculated for Caucasian and Asian 12-15-year-olds between 1982 and 1990 as 2.31 and 2.47 per 1000 respectively. There was an excess of girls in each group.

Chronic depersonalisation neurosis au Shorvon--a successful intervention

A patient with chronic primary depersonalisation responded well to a combination of psychotherapy and abreaction.

Ethnic differences in adolescent self-poisoning: a comparison of Asian and Caucasian groups

A study of self-poisoning in 25 Asian and 25 Caucasian adolescents is presented. Cultural conflicts were the most important factors in the parasuicidal behaviour of Asian children, whereas a variety of factors accounted for the parasuicidal behaviour of Caucasians with a predominance of a disrupted family background. There was little difference in the type of poisoning and the degree of pre-planning between the two groups.