Computed tomography in the elderly. 2. Senile dementia: diagnosis and functional impairment

Delusions, hallucinations and depression in Alzheimer's disease: A biological perspective

Three symptoms complicating Alzheimer's disease - delusions, hallucinations, and depression - are discussed from a biological perspective. Relevant clinical, radiological and pathological data are reviewed and hypotheses are advanced regarding the possible biological mechanisms of these phenomena. In addition, pharmacological and physical treatments of delusions, hallucinations and depression in Alzheimer's disease are discussed. Areas for future research are suggested.

Prospective evaluation of the role of atherosclerosis on cerebral atrophy: pilot study

PURPOSE

Our purpose was to study the association between atherosclerosis measured by arterial calcium on computed tomography (CT) and cerebral atrophy demonstrated by brain magnetic resonance imaging (MRI).

MATERIALS AND METHODS

IRB approved this prospective study. Twenty-one consecutive patients with acute stroke-like symptoms who are scheduled to have brain MRI were recruited on a voluntary basis. electrocardiogram (ECG)-gated helical CT scans were used to determine the arterial calcium as a reliable index of underlying atherosclerosis. Extracranial arterial calcium content was measured quantitatively by special software available in our CT scanner. Intracranial calcium was graded qualitatively. Brain MRI was independently evaluated to identify cortical, central atrophy, and ischemic changes. Relationship between CT demonstrated atherosclerosis and cerebral ischemic changes, brain atrophy patterns were evaluated both without and with adjustment for age and hypertension.

RESULTS

Out of 21 patients 20 were included in final study group. There was no correlation between atherosclerotic calcium measures and cortical atrophy, ischemic findings. Both intracranial and extracranial atherosclerosis had partial correlation with central atrophy (R= 0.43 and 0.52, respectively). After adjustment for age, only intracranial atherosclerosis maintained a partial correlation with central atrophy (R= 0.41). However, this correlation did not reach a statistically significant level (P= .10).

CONCLUSIONS

Intracranial atherosclerosis demonstrated a possible correlation with central atrophy.

Is intracranial atherosclerosis an independent risk factor for cerebral atrophy? A retrospective evaluation

Background

Our purpose was to study the association between the intracranial atherosclerosis as measured by cavernous carotid artery calcification (ICAC) observed on head CT and atrophic changes of supra-tentorial brain demonstrated by MRI.

Methods

Institutional review board approval was obtained for this retrospective study incorporating 65 consecutive patients presenting acutely who had both head CT and MRI. Arterial calcifications of the intracranial cavernous carotids (ICAC) were assigned a number (1 to 4) in the bone window images from CT scans. These 4 groups were then combined into high (grades 3 and 4) and low calcium (grades 1 and 2) subgroups. Brain MRI was independently evaluated to identify cortical and central atrophy. Demographics and cardiovascular risk factors were evaluated in subjects with high and low ICAC. Relationship between CT demonstrated ICAC and brain atrophy patterns were evaluated both without and with adjustment for cerebral ischemic scores and cardiovascular risk factors.

Results

Forty-six of the 65 (71%) patients had high ICAC on head CT. Subjects with high ICAC were older, and had higher prevalence of hypertension, diabetes, coronary artery disease (CAD), atrial fibrillation and history of previous stroke (CVA) compared to those with low ICAC. Age demonstrated strong correlation with both supratentorial atrophy patterns. There was no correlation between ICAC and cortical atrophy. There was correlation however between central atrophy and ICAC. This persisted even after adjustment for age.

Conclusion

Age is the most important determinant of atrophic cerebral changes. However, high ICAC demonstrated age independent association with central atrophy.

Neuropsychological functioning and delusions in dementia: a pilot study

The present pilot study investigated the pattern of neuropsychological functioning associated with the presence of delusions in mild-to-moderate dementia. Participants, all of whom met criteria for dementia, were divided into two groups, delusional (n = 9) and non-delusional (n = 9). Individuals with hallucinations were excluded. Participants completed a neuropsychological test battery. Global cognitive functioning (MMSE) and behavioral disturbance (BEHAVE-AD) were also assessed. Differences between the delusional and non-delusional group were most marked for immediate recall of stories, which was higher in the non-delusional group. Scores on semantic fluency, attention (mental control), and overall cognitive functioning (MMSE) were also lower in the delusional group. Conversely, simple attention span (Digit Span) was within normal limits in both groups. Floor effects were noted on measures of delayed recall and alternating attention. This study supports previous findings of greater neuropsychological impairment in delusional as compared to non-delusional individuals with dementia. However, some areas of cognitive functioning may be relatively preserved. Future research should examine semantic processing in persons with dementia with and without delusions.

Review of delusions in dementia

Although delusions are common symptoms in dementia and are associated with a number of adverse outcomes, research in this area has been limited. This article attempts to summarize the existing literature on delusions in dementia with respect to known risk factors, etiology, pathogenesis, neurocognitive findings, behavioral symptoms, and treatment. This study reviews all relevant abstracts and articles pertaining to delusions and dementia. The reviewers found that the studies were limited by confusion concerning phenomenology. However, consistent findings show that delusions are associated with certain demographic variables, neuropathologic and neurocognitive findings, adverse behavioral outcomes, and limited treatment response. The authors conclude that further longitudinal studies with better clarification of terminology are required to clarify inconsistencies and shed light on future treatment options.

Differences in the behavioral and psychological symptoms between Alzheimer's disease and vascular dementia: are the different pharmacologic treatment strategies justifiable?

BACKGROUND

This study aimed (1) to compare the behavioral and psychological symptoms of dementia (BPSD) between patients with Alzheimer's disease (AD) and vascular dementia (VaD); (2) to investigate the differences in the correlates of BPSD between them; and (3) to suggest potential different pharmacological strategies in treating BPSD of either etiology.

METHODS

In a study group of 135 patients with dementia (99 AD, 36 VaD), information on age, gender, education, age at onset and duration of dementia was collected. The severity of dementia was measured by the following assessment scales: Korean version of Mini-Mental State Examination (MMSE-K) for cognitive function; Blessed Dementia Scale (BDS) for functional activities of daily living (ADL); Barthel Index (BI) for physical ADL; and Brief Psychiatric Rating Scale (BPRS), Hamilton Depression Scale (HAM-D) and Hamilton Anxiety Scale (HAM-A) for BPSD. The independent variables between the patients with AD and VaD were compared, and then the correlations of BPSD with other variables were estimated.

RESULTS

HAM-D and HAM-A scores were higher in patients with VaD than in those with AD, while other variables demonstrated no statistical differences. BPRS score correlated with scores on MMSE-K, BDS and BI in AD, but only with BDS in VaD. The HAM-D score correlated with scores on BDS and BI in AD, but only with BDS in VaD. The HAM-A score was correlated with score on BDS in AD not in VaD.

CONCLUSIONS

BPSD were more severe in the patients with VaD. However, BPSD correlated more prominently with cognitive or ADL impairments in patients with AD. Different treatment approaches to BPSD may be required according to the clinical differentiation of dementia type.

Depressive symptoms in patients with Alzheimer's disease

OBJECTIVES

A comparison was made between the depressive symptom profiles of thirty patients with Alzheimer's disease (AD) who did not have co-existing depression and thirty patients with major depression who did not have co-existing dementia. The main objective was to identify symptoms common to both disorders and those which may be able to differentiate AD from major depression.

METHOD

A sample of patients suffering from either AD (n = 30) or major depression (n = 30) were recruited from a specialist old age psychiatry service. Depressive symptoms were profiled using the Hamilton Depression Rating Scale (HDRS), the Cornell Scale for Depression in Dementia (CSDD) and the Geriatric Depression Scale (GDS).

RESULTS

Depressive symptoms were present in AD in the absence of coexistent major depression. Certain depressive symptoms from all the three scales such as sadness, diurnal variation in mood and early or late insomnia were able to differentiate the two disorders with almost 90% accuracy while symptoms such as irritability, retardation and weight loss were common to both and were unable to differentiate the two.

CONCLUSION

Depressive symptoms occur in AD when co-existing depression is ruled out. Their recognition has implications for the diagnosis of major depression in these patients.

Relationship of behavioral and psychological symptoms to cognitive impairment and functional status in Alzheimer's disease

OBJECTIVE

This cross-sectional study examined the relationship of behavioral and psychological symptoms to cognitive and functional impairment in Alzheimer's disease (AD).

DESIGN

One hundred and fourteen patients were evaluated consecutively at a university-affiliated outpatient memory disorders clinic and diagnosed with possible or probable Alzheimer's disease (AD) according to NINCDS-ADRDA criteria. Subjects were assessed with the Behavioral Pathology in Alzheimer's Disease Scale (BEHAVE-AD), Revised Memory and Behavior Problem Checklist (RMBPC), Blessed Dementia Scale (BDS), and Mini-Mental State Examination (MMSE).

RESULTS

Several symptoms of behavioral pathology showed associations with MMSE scores, including activity disturbances, delusions, and hallucinations. After controlling for the variance associated with the MMSE, activity disturbances, diurnal disturbances, delusions, and hallucinations were linked with BDS scores.

CONCLUSIONS

The results suggest that some non-cognitive symptoms may be related to the neurobiologic mechanisms underlying the increased cognitive dysfunction in AD. Specific symptoms of behavioral pathology may also impact a patient's ability to perform important self-maintenance behaviors.

CT measurement of medial temporal lobe atrophy in Alzheimer's disease, vascular dementia, depression and paraphrenia

OBJECTIVE

Measurement of medial temporal lobe atrophy (MTL) by computerised tomography (CT) may be a useful adjunct to the diagnosis of AD. The aim of this study was to assess the sensitivity, specificity, predictive values and diagnostic accuracy of CT measurement of MTL thickness for patients with probable AD, compared with a 'diseased' control group, and to correlate the measure with neuropsychological test scores.

DESIGN

Cross-sectional.

METHODS

One hundred subjects were prospectively recruited: 60 with probable AD (mean age 73.7 years, mean Mini-Mental State Examination [MMSE] 19.6), 17 with probable vascular dementia (VaD) (mean age 77.9 years, mean MMSE 20.9), 14 with depression (mean age 73.2 years, mean MMSE 25.7) and nine with paraphrenia (mean age 74 years, mean MMSE 25.4). Axial and temporal lobe-oriented CT brain was performed and the minimum MTL thickness was measured electronically.

RESULTS

The mean minimum MTL thickness was significantly smaller in AD subjects compared to VaD (p<0.0001) and psychiatric subjects (p<0.0001). For the clinical diagnosis of probable AD, the sensitivity of the measure was 0.75, specificity 0.9, and diagnostic accuracy 0.81. For the mildest cases of AD (CDR 0.5), the sensitivity of the measure was 0.61, specificity 0.91, and diagnostic accuracy 0.81. No significant correlations with neuropsychological test scores were found.

CONCLUSIONS

Temporal lobe-oriented CT imaging is a non-invasive test with good discrimination for AD. Potential uses of this technique include as an aid to diagnosis and possibly as a means of monitoring disease progression.

[Psychiatric symptoms among patients with dementia seen in an ambulatory service]

Subjects with dementia often display an array of neuropsychiatric symptoms that include disorders of mood, delusions, hallucinations, vegetative symptoms and psychomotor abnormalities. The present study was designed to investigate the prevalence of psychiatric morbidity amongst patients with the clinical diagnosis of dementia (ICD-10) assessed at a Memory Clinic in São Paulo-Brazil between February 1997 and May 1998. The mental and cognitive state of patients were assessed with an extended version of the SRQ-20 and the MMSE respectively. Thirty-four (45.3%) out of a total of 75 subjects scored 8 or more on the SRQ-20, indicating the presence of significant psychiatric morbidity. Depressive symptoms were reported by 69.3% of patients. Persecutory ideas and auditory hallucinations were observed in 20.0% and 16.0% of the sample respectively. Eight subjects (10.7%) described suicidal ideation--they all displayed depressive symptoms. Patients with scores on the SRQ-20 > or = 8 or who described suicidal ideation were significantly younger than their counterparts. Auditory hallucinations were more frequent amongst subjects with lower MMSE scores. There were no sex differences in the distribution of the psychiatric symptoms under investigation. The assessment of patients with dementia should always include a detailed psychiatric examination, as the detection and treatment of such symptoms may contribute to decrease the stress of patients and the burden on carers.

Use of computerized tomography by old age psychiatrists: an examination of criteria for investigation of cognitive impairment

OBJECTIVES

To determine the prevalence of the Royal College of Psychiatrists' consensus criteria for the detection of potentially reversible intracranial pathology in a group of patients over 65 years old referred for computerized tomography (CT) head scanning from a specialist old age psychiatry service, to test the association of Royal College audit criteria with the presence of potentially reversible intracranial pathology.

METHODS

A retrospective case-note survey of all patients referred from Psychiatric Services for the Elderly at High Royds Hospital to the Neuro-imaging Suite at Leeds General Infirmary in the period April 1994-March 1996.

RESULTS

The records of 143 patients were examined. One or more guideline items were present in the notes in 97 (67.8%) subjects. Ten cases of potentially reversible intracranial pathology were detected and all were correctly predicted by the Royal College guidelines. All were in patients of 71 years of age or older. The false positive rate for the guidelines was 89%. History duration of less than 1 year was the only guideline found to be associated with the detection of potentially reversible intracranial pathology.

CONCLUSIONS

The Royal College of Psychiatrists' consensus criteria can correctly classify patients with potentially reversible intracranial pathology but lack the specificity to usefully reduce unnecessary CT referral or act as valid audit criteria.

Relationship between brain atrophy estimated by a longitudinal computed tomography study and blood pressure control in patients with essential hypertension

To evaluate the relationship between blood pressure control and the progression of brain atrophy in the elderly, patients with essential hypertension and brain atrophy were longitudinally evaluated using computerized tomography (CT). The study evaluated 48 patients with essential hypertension aged 46-78 years, and 30 sex- and age-matched normotensive control subjects. The extent of brain atrophy as determined by caudate head index (CHI), the inverse cella media index (iCMI), and Evans' ratio (ER) was estimated twice at an interval of 5-9 years (mean, 6.9 years). The mean annual increases in CHI (deltaCHI), iCMI (delta iCMI), and ER (deltaER) were evaluated. Mean blood volume in the common carotid artery (BF) and the decrease in BF per year (deltaBF) were also determined. The deltaCHI, delta iCMI, and deltaER increased with age in the hypertensive subjects as well as the control group across all age groups evaluated. The deltaCHI, delta iCMI, and deltaER were significantly greater in the patients with essential hypertension in their 50 s as compared with the controls. In patients with essential hypertension aged 65 years or older, the deltaCHI, delta iCMI, and deltaER were significantly lower in the group in whom the blood pressure was controlled within the range of borderline hypertension than the groups in which it was controlled in the range of normal or mild hypertension. In the younger patients under the age of 65 with essential hypertension, blood pressure control did not affect the deltaCHI, delta iCMI, and deltaER. The deltaCHI, delta iCMI, and deltaER were significantly correlated with deltaBF in both groups. These findings indicate that control of systolic blood pressure within the range of borderline hypertension may delay the progression of brain atrophy in elderly patients with essential hypertension.

Temporal lobe abnormalities in dementia and depression: a study using high resolution single photon emission tomography and magnetic resonance imaging

OBJECTIVES

Perfusion SPECT and MRI were used to test the hypothesis that late onset depression is associated with brain abnormalities.

METHODS

Forty depressed patients (DSM-III-R major depressive episode, not demented at two year follow up) were recruited who were either drug free, or on a stable dose of antidepressants for at least three weeks, as well as 22 demented patients (DSM-IIIR and NINCDS/ADRDA criteria for probable Alzheimer's disease). Patients were imaged at rest with a high resolution single slice 12 detector head scanner (SME-Neuro 900) and the cerebral perfusion marker 99mTc-exametazime (HM-PAO). Temporal lobe templates were fitted with brains pitched by 20 degrees-30 degrees. A subgroup of 41 patients (22 depressed) were also scanned using a Siemens Magnetron 1.0 Tesla magnetic resonance imager, using a FLAIR imaging sequence for the assessment of white matter hyperintensities, and a Turbo FLASH sequence for the measurement of medial temporal lobe width.

RESULTS

Demented patients showed reduced perfusion, particularly in the left temporoparietal cortex. In these regions of interest, patients with late onset depression tended to have perfusion values intermediate between patients with early onset depression and demented patients. Differences in changes in white matter between demented and early and late onset depressive patients did not reach conventional levels of significance. Temporal lobe width differed between demented and depressed patients, but not between early and late onset depressed patients. Perfusion and temporal lobe width were not associated, but reductions of perfusion were associated with periventricular white matter changes. Mini mental state examination scores were associated with temporal perfusion in demented patients and with changes in deep white matter in depressed patients. Finally, severity of depressive symptoms was associated with decreased perfusion in frontotemporal and basal ganglia regions of interest.

CONCLUSION

A cumulative effect of duration of illness on regional cerebral perfusion could not be confirmed. Late onset depression may show more abnormalities of deep white matter and of left temporoparietal perfusion than early onset depression, but the underlying pathology remains to be established.

Neuropathological and neuroradiological correlates of paranoid symptoms in organic mental disease

This paper reviews paranoid symptoms in older patients with organic mental disease. We have taken a dual approach to this topic, examining patients with dementia in whom paranoid symptoms are present and also assessing the presence of organic brain changes in patients diagnosed as having late-onset schizophrenia, paraphrenia or delusional disorder. (For the sake of continuity and not wishing to pre-empt any discussion of the nosological categorisation of late-onset psychoses, we refer to late-onset persecutory state as paraphrenia.) Firstly, there is a description of the various paranoid symptoms which have been described in patients with dementia. Secondly, brain imaging studies are discussed which have highlighted changes in patients with paraphrenia and particular associations between psychotic phenomenology and brain changes in patients with dementia. Thirdly, neuropathological and neurochemical changes in the brains of patients with dementia in whom paranoid symptoms have been present are presented. We intersperse all three sections with data from work carried out by the authors at the Institute of Psychiatry in London from 1986 and 1992. For other reviews, see Allen and Burns (1995), Burns and Förstl (1996), Eisiri (1996) and Howard (1996).

A double-blind, placebo-controlled study of tacrine in patients with Alzheimer's disease using SPET

BACKGROUND

the effect of single-dose and long-term cholinergic enhancement with tacrine on regional cerebral perfusion was examined in patients with Alzheimer's disease using single-photon emission tomography (SPET).

METHOD

23 patients with probable Alzheimer's disease (DSM-III-R and NINCDS-ADRDA criteria) were scanned before and after a single oral dose of tacrine at the start of the study and again after 12 weeks of randomized, double-blind treatment with tacrine or placebo, using high resolution (99m)Tc-Exametazime SPET. Patients also underwent neuropsychological testing with the CAMCOG, the Mini-Mental State Examination and the Rivermead Behavioural Memory Test before and after 12 weeks of treatment.

RESULTS

occipital count ratios in all regions of interest declined by 3% over 12 weeks, indicating a progression of the disease. Acute tacrine challenge resulted in a 16% increase in the superior frontal and a 11% decrease in the anterior temporal cortex. The acute effects of tacrine were modified by 12 weeks of treatment, particularly in the medial frontal (cingulate) cortex where active treatment was associated with a reduced acute tacrine response. There were no changes in cognitive function associated with active treatment.

CONCLUSION

the study demonstrates the sensitivity of cerebral perfusion measures to changes during acute and medium-term tacrine treatment.

Brain atrophy in normal ageing and Alzheimer's disease. Volumetric discrimination and clinical correlations

BACKGROUND

We examined the differences in volume of the ventricular and extracerebral cerebrospinal fluid spaces in normal ageing and in probable Alzheimer's disease (AD) and we tried to investigate the effects of the severity of illness on the morphometric differentiation of AD and ageing, the principal components underlying brain atrophy in both conditions, and the correlations of these measurements with clinical findings.

METHOD

Forty patients with probable AD were matched with 40 non-demented elderly controls. Both groups underwent standardised clinical tests and unenhanced cranial computed tomography for post hoc volumetric analysis.

RESULTS

The lateral and third ventricles and the anterior and lateral fissures were significantly larger in AD than in normal ageing. The volumes of the lateral ventricle and lateral fissure permitted a highly efficient differentiation between normal ageing and AD even at the mild stage of dementia, and this differentiation was improved further in the more severe stages of illness. We identified one principal component underlying brain atrophy in normal ageing and two components in AD: a 'grey matter' component accounting for sulcal and third ventricular enlargement, and a 'white matter' component for lateral ventricular enlargement. In AD, most of the volumetric measurements were significantly correlated with cognitive impairment, but in the group of non-demented elderly controls they were correlated with age. CONCLUSION. Volumetric indices of brain atrophy permit a highly efficient differentiation between normal ageing and AD even in the mild stages of illness and this demonstrates that substantial structural brain changes have developed in the preclinical phase of illness. We suggest that there is an uncoupling between lateral ventricular enlargement and cortical brain atrophy in AD.

Biologic markers and neurochemical correlates of agitation and psychosis in dementia

Behavioral and psychiatric symptoms frequently accompany the cognitive deterioration of dementia occurring in up to 80% of both community-based and nursing home patients. In Alzheimer's disease (AD), behavioral complications may develop at any stage of the disease process and tend to follow a more unpredictable course than the core cognitive symptoms. Over the past 15 years, our knowledge of the biologic and neurochemical basis of dementia, and of AD in particular, has increased significantly. Great emphasis has been placed on the cholinergic system abnormalities in the context of the cognitive impairment in AD and on the psychopharmalogic enhancement of cholinergic transmission in AD. However deficits in other neurotransmitter systems, such as the noradrenergic, serotonergic, and dopaminergic systems, also occur and may contribute to the core cognitive symptoms of AD. More recently, there has been increased interest in the biologic and neurochemical basis of behavioral and psychiatric disturbances in dementia. This article reviews the evidence for biologic and neurochemical correlates of psychosis and agitation in dementia, and discusses the treatment implications for these findings.

Posterior superior temporal gyrus in schizophrenia: grey matter changes and clinical correlates

We report an MRI morphometric study of the posterior segment of the superior temporal gyrus (STG) in twenty young male schizophrenics and their individually matched normal controls. In particular the more posterior segment of STG was examined, since it has been identified as the approximate site of Wernicke's language area and is a marker for the planum temporale, a region believed to be abnormal in schizophrenia. Total volumes and grey and white matter volumes were measured in middle and posterior STG in each hemisphere. STG grey matter volumes and percentages were significantly reduced bilaterally in both regions in schizophrenic subjects. No significant differences between patients and controls were noted in STG white matter volumes. A significant correlation was detected between delusion scores in schizophrenics and the total volume of the left dominant posterior STG. Replicating the findings of a recent study (Shenton et al., 1992), we found an inverse correlation between thought disorder scores and grey matter reduction in the left posterior STG in schizophrenia.

Clinical and cognitive diversity of psychotic states arising in late life (late paraphrenia)

This study aimed to explore the heterogeneity of paranoid psychosis with onset in late life by using cognitive factors in a centroid method of cluster analysis. Forty-seven subjects were allocated to two different clusters, the first with 24 (51.1%) and the second with 23 (48.9%) patients. Their cognitive attainment was evaluated against the performance of 33 elderly controls, all groups being matched for age, sex, and the numbers of years of education. Patients in cluster 2 showed a pattern of widespread cognitive impairment, which involved general measures of cognitive performance (MMSE, CAMCOG, WAIS-R verbal and performance scores), memory (digit and spatial span, delayed matching-to-sample, recognition memory for words and faces), and executive functions (verbal fluency, extra and intra-dimensional shift ability, spatial working memory, and planning). In contrast, patients in cluster 1 were only impaired on their extra-dimensional set shift and planning abilities, suggesting a more specific and restricted executive functioning deficit. We also analysed the impact that the use of antipsychotic medication could have had on patients' cognitive performance, which was shown to be negligible. In addition, there was no difference between the clusters with regard to the number of patients using neuroleptics, suggesting that the medication was unlikely to have introduced a performance bias in the two patient clusters. The validity of the subdivision of these patients into two separate groups was further supported by other clinical findings. Patients in cluster 1 exhibited more severe psychotic symptoms, as measured by the SAPS, than their counterparts in cluster 2, and were also more likely to display first-rank symptoms of Schneider. Conversely, cluster 2 membership was strongly associated with the presence of neurological signs and negative symptoms. We suggest that psychotic states arising in late life are a heterogeneous condition that may be best divided in two: 'type A', including patients with a wide range of psychotic symptoms, mild increase in the frequency of neurological signs, and cognitive deficits restricted to executive functions, and 'type B', which includes patients with less complex psychotic symptoms associated with a marked increase in the frequency of neurological signs and generalized cognitive impairment. The basis for this subdivision and the prospect for future studies are discussed.

Delusions and dementia: clinical and CT correlates

INTRODUCTION

Delusions occur frequently during the course of Alzheimer's disease (AD) and multi-infarct dementia (MID). Their clinical significance and their relationship with progression of disease and involvement of selected cerebral areas are still unclear. The aim of the study was to determine the clinical and CT correlates of delusions in patients with dementia.

MATERIAL AND METHODS

A series of 67 probable AD and 32 MID patients, underwent computed tomographic scans, psychometric tests, neurologic and psychiatric examination, and blood and serum tests.

RESULTS

Twenty-four patients were found to have delusions during the clinical evaluation. Delusional patients showed a significantly higher age when compared with non-delusional patients. The results of a multiple logistic regression (with stepwise deletion of the redundant variables) of the CT lesions on the presence of delusions, showed that only the presence of isolated white matter lesions in the frontal lobes were significantly related to the occurrence of delusions (Exp B = 3.42; Beta = 1.2; S.E. = 0.6; Sig T = 0.04). Frontal white matter changes were significantly related to delusions when a multiple regression analysis, entering age and total number of lesions at CT scans, was carried out.

CONCLUSIONS

We found that focal lesions in the frontal areas were the only variable that appeared to be significantly and independently associated with delusional disorders.

Neuropathological correlates of psychotic phenomena in confirmed Alzheimer's disease

BACKGROUND

The prevalence of psychotic phenomena in confirmed Alzheimer's disease (AD) and their potential neuropathological correlates have rarely been the subject of prospective investigation.

METHOD

Psychopathological disturbances were recorded prospectively according to the Geriatric Mental State Schedule and the CAMDEX: The frequency of these phenomena and neuropathological changes were examined in 56 patients with definite AD.

RESULTS

Hallucinations had been documented in 13 patients, paranoid delusions in 9 and delusional misidentification (e.g. the Capgras-type and the 'phantom boarder' symptoms) in 14 patients. Misidentifications were associated with lower neurone counts in the area CA1 of the hippocampus. Delusions and hallucinations were observed in patients with less severe cell loss in the parahippocampal gyrus and with lower cell counts in the dorsal raphe nucleus. A decrease of neurones in the locus coeruleus in a subset of depressed patients with AD had been reported earlier. Delusions and delusional misidentification were common in 5 patients with basal ganglia mineralisation, but there was no statistically significant association of these symptoms with the presence of Lewy bodies in the brainstem and neocortex of our patient sample.

CONCLUSIONS

These findings are compatible with the view that morphological changes in certain brain areas may promote the development of psychotic phenomena in AD. AD may offer a model for the understanding of pathomechanisms underlying the development of psychopathological disturbances in other psychoses with more discrete neuropathological changes.

The management of other psychiatric states. Hallucinations, delusions, and other disturbances

The behavioral disturbances that are most common in Alzheimer's disease are not those directly associated with the core characteristics of the disease; however, they often cause the most difficult problems of management. These disturbances include agitation, hallucinations, and delusions. This article reviews their prevalence, etiology, differential diagnosis, and management.

[Contribution of morphological imaging in the diagnosis of dementia. I--Alzheimer disease]

In patients with Alzheimer's disease, morphological neuroimaging techniques usually reveal signs of global cerebral atrophy which gradually worsen over time and depends on age and severity of the cognitive decline. Because of the lack of artifacts and of a more appropriate angle, magnetic resonance imaging scans may visualize a prominent atrophy of the medial temporal lobes, including hippocampal structures. Hippocampal atrophy is relatively specific of Alzheimer's disease before 65 and is related to the severity of memory disorders. White matter changes in patients without cerebrovascular risk factors are not more severe in patients with presenile Alzheimer's disease than in age-matched controls. They are, however, more severe in patients with senile onset than in age-matched controls. These findings suggest that white matter changes in patients with senile onset are consistent with a diagnosis of Alzheimer's disease.

MRI volumetric studies in Alzheimer's disease: relationship to clinical and neuropsychological variables

The authors studied 34 subjects with probable dementia of the Alzheimer type (DAT) and 28 healthy, age-matched control subjects, using a 1.5-tesla GE MRI scanner. Absolute volumes of ventricular and sulcal cerebrospinal fluid spaces and volumes, corrected for total intracranial volume, were significantly higher (P < 0.01) in the DAT group, compared to the control group. Right-left measures of hemispheric structural asymmetry were greater in the DAT group, whereas aging alone influenced brain structure in the control group. Also, in the DAT group, certain volumetric measures were significantly correlated with specific clinical indicators of severity of illness and some neuropsychological indices. These data demonstrate widespread structural abnormalities in relatively early DAT and a relationship between brain structure and some measures of cognitive dysfunction.

Age-dependent cerebral metabolic effects of unilateral nucleus basalis magnocellularis ablation in rats

To investigate the age-dependent functional importance of cholinergic neocortical inputs, and to explore whether cortical cholinergic denervation in aged animals might better model the cerebral metabolic changes of Alzheimer's disease, the effects of unilateral ablation of the nucleus basalis magnocellularis (NBM) on cerebral glucose metabolism were studied in young and aged rats. Regional cerebral metabolic rates for glucose (rCMRglc) were determined, using the [14C]deoxyglucose method, in 48 brain regions of 3- and 24-month old Fischer-344 rats at 3, 7, 14 and 28 days after stereotaxic injection of ibotenate into the right NBM, and in sham-operated animals at 3 and 14 days later. For both ages the peak effect of unilateral NBM ablation occurred 3 days later: in young rats, rCMRglc was significantly reduced (compared to the contralateral side) in all 24 anterior cortical areas examined (mean decline 20%), whereas in aged animals, only 9 of 24 areas showed a significant decline in glucose utilization, and the magnitude of rCMRglc reduction (9%) was smaller. Near complete recovery of rCMRglc occurred by 7 days in young and old rats. We conclude that the basalocortical cholinergic projection plays a smaller role in neocortical function of aged rats, possibly because its tonic activity is reduced. Both young and aged rats undergo cortical metabolic normalization after unilateral NBM ablation; hence the NBM-lesioned aged rat is not a better model of the progressive decline in rCMRglc that occurs in Alzheimer's disease.

First-rank symptoms of Schneider in late paraphrenia. Cortical structural correlates

The brains of 41 late paraphrenics, 16 of whom had first-rank symptoms, were examined by CT. Late paraphrenics with first-rank symptoms had significantly less cortical atrophy than those without them.

Computerised tomography in Alzheimer's disease. Methods of scan analysis, comparison with normal controls, and clinical/radiological associations

One hundred and thirty-eight patients satisfying NINCDS/ADRDA criteria for Alzheimer's disease (AD) and 36 normal controls underwent cranial CT. A comparison of methods of scan analysis showed good agreement between computer-assisted methods and visual ratings and planimetry. The CT scans of controls differed significantly from patients and a discriminant analysis, based on all CT measures, predicted group membership (control or patient) in 81% of cases. Within the AD group, cortical atrophy correlated with age and duration of illness. Global tests of cognitive function correlated significantly with both cortical atrophy and ventricular size. Subjects who died in a three-year follow-up had more atrophy and larger third ventricles than survivors, but this effect was due entirely to increased age.

Centrum semiovale white matter CT changes associated with normal ageing, Alzheimer's disease and late life depression with and without reversible dementia

A standardized, reliable means of assessing CT attenuation numbers in the centrum semiovale and surrounding grey matter was developed. This was applied to cranial CT scans of 60 normal controls (36 aged greater than 60 years), 25 elderly patients with major depression (14 of whom had the dementia syndrome of depression), and 10 patients with Alzheimer's disease (AD). Subjects received neuropsychological evaluation. Centrum semiovale (CSO) CT attenuation numbers decreased with increasing age for both white and grey matter. White matter attenuation values best discriminated elderly controls from the three patient groups. Both white and grey matter CSO attenuation values correlated with performance on a number of cognitive tasks.

Cerebral structure on MRI, Part II: Specific changes in Alzheimer's and Huntington's diseases

Using magnetic resonance (MR) imaging and morphometric techniques, groups of patients with Alzheimer's disease (AD) and Huntington's disease (HD) were compared with a large group of normal control subjects. Measures of volume loss in specific subcortical nuclei and eight cortical regions as well as an index of white matter abnormality were obtained. Results indicated expected widespread cortical volume reductions in AD, which were especially severe in mesial cortices; but comparable reductions were present in subcortical structures, particularly the thalamus. In HD, the greatest reductions were in striatal structures, but significant abnormalities were also detected in the thalamus and inferior cortical areas, especially in mesial temporal lobe structures. Significant degeneration in white matter was present in both groups, but was more dramatic in the HD patients. The significant diencephalic reduction in AD may make an important contribution to early memory deficits in the disorder, which are usually attributed to hippocampal damage. Similarly, damage to both the thalamus and mesial temporal lobe structures may play a role in the memory deficits of HD.

Psychiatric phenomena in Alzheimer's disease. IV: Disorders of behaviour

Out of a sample of 178 patients with AD, aggression was present in 20%, wandering in 19%, binge-eating in 10%, hyperorality in 6%, urinary incontinence in 48%, and sexual disinhibition in 7%. Behavioural abnormalities were greater in those with more severe dementia. Temporallobe atrophy correlated with aggression, and widening of the third ventricle with hyperorality. Features of the Kluver-Bucy syndrome were commonly seen, but the full syndrome occurred in only one subject. Patients with at least one feature of the Kluver-Bucy syndrome had greater temporal-lobe atropy than those without any of the features.

Psychiatric manifestations of frontal lobe tumours

In a recent article in the British Medical Journal Maurice-Williams & Dunwoody (1988) reported two patients with frontal meningiomas who presented initially to psychiatrists. The correct diagnosis was made in one of them after prolonged, perhaps unnecessary, psychiatric treatment. In the other the diagnosis was made at autopsy. In this case psychiatrists were only briefly involved and neurosurgical referral had been made promptly. The authors, who treat these reports as a cautionary tale, conclude by warning psychiatrists to pay special attention to a number of features in the history and examination of psychiatric patients. In particular we are told that suspicion should arise in the presence of gradual non-remitting symptoms such as irritability, memory loss, self-neglect, dysphasia or incontinence in patients without a previous history of psychiatric disease or clear precipitating factors. They also suggest that we pay attention to the views of relatives when they feel the patient suffers from a physical rather than a psychiatric illness, and emphasise that early diagnosis leads to easier surgical removal and better outcome.

Structural brain CT changes and cognitive deficits in elderly depressives with and without reversible dementia ('pseudodementia')

Twenty-six elderly (greater than 60 yrs) patients with DSM-III major depression were compared to 13 patients with NINCDS/ADRDA probable Alzheimer's disease (AD), and to 31 screened normal controls. Subjects were matched on age and sex. Fifteen of the 26 depressed patients were cognitively impaired on the Mini-Mental State Examination (MMSE) upon admission, but after treatment returned to the normal range. These 15 patients were defined as having the dementia syndrome of depression (DOD). The remaining 11 depressed patients were termed depressed, cognitively normal (DCN). All subjects received standardized cranial CT scans for assessment of ventricular brain ratio (VBR) and CT attenuation numbers. Subjects also received neuropsychological evaluation. CT values for the 26 depressed patients lay between those of AD patients and normal controls. CT values for the DOD subgroup clustered near those of AD patients. Patterns of cognitive deficits and correlations of CT attenuation values with cognitive measures were also similar in AD and DOD. Most patients were reassessed at a mean of two years after initial testing; of the 11 of the 15 DOD re-examined, only one had undergone cognitive decline. By contrast, all AD patients retested had declined significantly. Episodes of DOD and DCN tended to 'breed true'. This study suggests that while patients with DOD may have underlying structural brain abnormalities, obvious short-term progression to AD does not commonly occur.

An evaluation of cranial CT scanning in clinical psychiatry

From 6,300 psychiatric admissions over a 37 month period, all 54 patient referrals for CT were identified and their charts reviewed. CT influenced diagnosis, management or prognosis in 11.7 percent of patients scanned. There was poor correlation between organicity on CT scan and findings on physical examination, laboratory testing, EEG and psychological testing. The mental state examination was the single significant correlate of CT abnormality. We suggest that the use of a formalised mental state examination such as the Mini Mental State, in addition to the usual clinical assessment of mental state, may improve the accuracy of prediction of abnormality on CT scan. The introduction of X-ray computed tomography (CT) is recognised to be one of the most important innovations in the recent history of clinical medicine. In neurology the value of a non-invasive technique for examining the intracranial contents was quickly realised in the areas of diagnosis, particularly in the detection of vascular accidents and tumours. CT has also attained a significant place in psychiatry. In research studies, it has provided important information on schizophrenia, alcoholism and chronic organic reactions. The place of CT in clinical psychiatry is less clear. As its availability has increased, such scans are being requested with increasing frequency in psychiatric patients. Cranial CT is a highly sensitive diagnostic procedure which, when used unselectively, may result in the discovery of incidental findings. Until recently, a function of the psychiatrist in relation to diagnosis was to first seek to distinguish symptoms produced by organic pathology from those produced by functional illness.(ABSTRACT TRUNCATED AT 250 WORDS)