Hallucinations In Other Modalities Research Articles

Olfactory hallucinations in a population-based sample

Olfactory hallucinations referring to olfactory perceptions in the absence of chemical stimuli, occur in non-clinical and clinical populations. Few studies have investigated their prevalence in the general population and little is known about factors triggering and maintaining them such as substance use, severe life events, and mood. We analyzed self-report data from 2500 community dwelling Norwegians, aged 18-96 years, for occurrence of olfactory hallucinations and co-occurring hallucinations in other modalities (auditory, visual, tactile). Analyses included age, sex, self-reported symptoms of depression and anxiety, mental health status, and experience of severe life-events. The results show that 4.2% (95% CI 3.5-5.1%) reported having experienced olfactory hallucinations, and 56% of individuals experiencing olfactory hallucinations also reported these in combination with hallucinations in other modalities. Prevalence varied significantly in terms of age and sex, in that olfactory hallucinations were most frequently reported by young individuals and females. Self-reported symptoms of anxiety and experience of stressful life events were significantly associated with olfactory hallucinations, suggesting that experiencing olfactory hallucinations may negatively affect functioning and may increase the likelihood of developing psychopathology. Findings underline the need to continue to examine olfactory hallucinations albeit with a more comprehensive assessment in order to increase knowledge on this experience.

Visual hallucinations associated with multimodal hallucinations, suicide attempts and morbidity of illness in psychotic disorders

BackgroundVisual hallucinations (VH) are a common, but understudied symptom of psychosis, experienced by individuals across diagnostic categories of psychotic and neuropsychiatric conditions. There are limited data on VH and associated clinical phenotypes in adult idiopathic psychotic disorders, which are needed to elucidate their relevance to psychotic illness paradigms. MethodIn this cross-sectional study, we examined clinical risk factors for VH in a well-characterized sample of 766 patients with adult psychotic disorders across diagnostic categories of schizophrenia (n = 227), schizoaffective disorder (n = 210), and bipolar I disorder (n = 329). The Structured Clinical Interview for DSM-IV-TR was used for diagnosis and symptom measurements. ResultsThe prevalence of VH was 26.1% (200/766). Multivariate logistic regression showed that VH were independently associated with the presence of hallucinations in other modalities, including auditory, tactile, olfactory, and gustatory hallucinations. History of a suicide attempt and catatonic behavior were also associated with VH. In addition, specific delusions were associated with VH, in particular, delusions of control, and religious, erotomanic and jealousy delusions. Diagnosis, negative symptoms, and family history of psychosis were not independent predictors of VH. ConclusionsResults showed the clinical and disease relevance of VH as they were associated with severe morbidity of illness, including suicide attempts and catatonic behavior. Findings also suggest a phenotype associated with hallucinations in other modalities and specific types of delusions. Based on our findings, VH may be a significant factor in assessing for suicidality and illness severity, warranting clinical attention and further study of underlying mechanisms.

Clinical Practice Guidelines for Management of Dementia.

Indian Psychiatric Society (IPS) published Clinical Practice Guidelines (CPGs) for management of dementia, in the year 2007. (http://www.indianjpsychiatry.org/cpg2007.asp). The current version of the CPG is an update of the earlier version of CPGs for management of dementia There were three separate CPGs for management of dementia, one each for Reversible Dementias, Alzheimer's Disease and Vascular Dementia, Please note that the present CPG on dementia deals all types of dementia together. The current version of the CPGs for dementia in elderly must be read in conjunction with the previous version of CPGs for dementia. The focus of the present CPG is to provide suggestions and clinical tips to differentiate dementia syndrome from other clinical conditions, identify the subtypes of dementia and then offer suggestions for management. These guidelines only provide a broad framework for assessment, management and follow-up of older people with dementia. While most of the recommendations are evidence based, these guidelines should not be considered as a substitute of professional knowledge and clinical judgment. The recommendations made as part of these guidelines should be tailored to address the clinical needs of the individual patient and the treatment setting.

SU111. A Comprehensive Phenomenological Examination of Auditory Verbal Hallucinations (AVHs): A Comparison of Mood vs Psychotic Disorders

Abstract Auditory verbal hallucinations (AVHs) refer to the perception of verbal utterances in the absence of corresponding external stimuli. These experiences encompass complex, multifaceted phenomena and often contribute to clinical distress, poor quality of life, and even suicidal ideation, especially in clinical populations. Though not uncommon in bipolar disorder (BD) and major depressive disorder (MDD), there has been scant AVH research in these areas. We therefore aimed to conduct a series of studies to elucidate the nature of AVH experiences in these mood disorders relative to schizophrenia (SCZ) and schizoaffective disorder (SZA). In Study 1, a systematic literature review was undertaken using specified search terms (ie, “hallucinations” or “hearing voices” in conjunction with “bipolar disorder,” “mania” or “manic-depressive” or “major depressive disorder” or “depression” or “affective disorders” or “mood disorder”). In Study 2, we recruited 117 clinical participants (BD = 27; MDD = 28; SCZ = 39; SZA = 23), and conducted in-depth, semistructured phenomenological interviews. Assessments amalgamated conventional psychosis measures, such as the Psychotic Symptoms Rating Scales (PYSRATS) and Scale for the Assessment of Positive Symptoms (SAPS), select items from the Mental Health Research Institute Unusual Perceptions Schedule (MUPS) as well as additional questions derived from consultations with expert clinicians and/or researchers in the field. In Study 1, 14 eligible peer-reviewed publications, selected on the basis of a set of predefined inclusion criteria, were analyzed. Two major conclusions were drawn: (1) AVHs remained a central but largely understudied symptom in these disorders, albeit with varying prevalence rates (BD = 11.3%–62.8%; MDD = 5.4%–40.6%) and (2) methodological challenges in existing studies limited collection of meaningful phenomenological information (Toh , 2015). In Study 2, participants were well-matched on major demographic and clinical variables, with the exception of age (BD = MDD SZA), and Voices Commenting (MDD < BD = SCZ). Largely similar physical characteristics, negative content, controllability, and distress were associated with voices across diagnoses, but AVHs in mood disorders tended to be less frequent and disabling than in psychotic disorders. Ongoing studies by our research group include similar phenomenological inquiry into hallucinations in other modalities (Study 3), associated delusional themes (Study 4), as well as longitudinal stability of these phenomena (Study 5planning).

Associations between nonauditory hallucinations, dissociation, and childhood adversity in first-episode psychosis

ABSTRACTAlthough repeated associations have been found between adversity exposure (particularly exposure to childhood sexual abuse), dissociation, and auditory hallucinations in the context of psychosis, there is little comparable research examining hallucinations in other modalities. This study aimed to determine whether cumulative adversity exposure influences the likelihood of experiencing visual, tactile, olfactory, and gustatory hallucinations among psychosis patients and whether measures of dissociation are significantly associated with nonauditory hallucinations when exposure to childhood adversity and psychological distress are adjusted for. Self-report measures and a retrospective case-control design were applied to assess nonauditory hallucinations, dissociation, psychological distress, and childhood adversity exposure in a sample of first-episode psychosis patients reporting nonauditory hallucinations (n = 36) and controls from the same clinical population without nonauditory hallucinations (n = 31). Case participants reported higher levels of dissociation, psychological distress, and exposure to childhood rape than the control group. Dissociation remained significantly associated with nonauditory hallucinations when we adjusted for childhood sexual abuse, other types of childhood adversity, and a combined measure of emotional distress. Indication of a dose–response relationship was detected, in that total number of adversities was significantly associated with reporting more than one modality of nonauditory hallucination. Observed associations between auditory hallucinations and dissociation in psychosis may extend to other hallucination modalities. It is suggested that more research attention be paid to the etiology and impact of nonauditory hallucinations in psychosis samples.

Reduced integrity of the left arcuate fasciculus is specifically associated with auditory verbal hallucinations in schizophrenia

BackgroundSchizophrenia patients with auditory verbal hallucinations (AVH) have reduced structural integrity in the left arcuate fasciculus (AFL) compared to healthy controls. However, it is neither known whether these changes are specific to AVH, as opposed to hallucinations or schizophrenia per se, nor how radial and/or axial diffusivity are altered. This study aimed to test the hypothesis that reductions to the structural integrity of the AFL are specifically associated with AVH in schizophrenia. MethodDiffusion tensor imaging scans and clinical data were obtained from the Australian Schizophrenia Research Bank for 39 schizophrenia patients with lifetime AVH (18 current, 21 remitted), 74 schizophrenia patients with no lifetime AVH (40 with lifetime hallucinations in other modalities, 34 no lifetime hallucinations) and 40 healthy controls. ResultsFractional anisotropy was significantly reduced in the AFL of patients with lifetime AVH compared to both healthy controls (Cohen's d=1.24) and patients without lifetime AVH (d=.72), including compared to the specific subsets of patients without AVH who either had hallucinations in other modalities (d=.69) or no history of any hallucinations (d=.73). Radial, but not axial, diffusivity was significantly increased in patients with lifetime AVH compared to both healthy controls (d=.89) and patients without lifetime AVH (d=.39). Evidence was found for a non-linear relation between fractional anisotropy in the AFL and state AVH. ConclusionReduced integrity of the AFL is specifically associated with AVH, as opposed to schizophrenia in general or hallucinations in other modalities. Increased radial diffusivity suggests dysmyelination or demyelination of the AFL may play a role in AVH.

Transient Charles Bonnet syndrome in a patient with reversible cerebral vasoconstriction syndrome

Charles Bonnet syndrome (CBS) was first described by a Swiss philosopher named Charles Bonnet in 1760. For a long time, this syndrome was considered to be rare; however, in 1996, Teunisse et al. [1] reported psychopathological characteristics of 60 patients with CBS and questioned the rarity of CBS. CBS is diagnosed if the following criteria are fulfilled: (a) the presence of formed and complex, persistent, or repetitive visual hallucinations; (b) full or partial retention of insight; (c) the absence of delusions; (d) and the absence of hallucinations in other modalities [2]. Reversible cerebral vasoconstriction syndrome (RCVS) is a disorder characterized with reversible segmental and multifocal vasoconstriction of cerebral arteries and severe headaches with or without focal neurological deficits or seizures. Calabrese et al. described the following features for RCVS: (a) transfemoral angiography or indirect [computed tomography (CT) or magnetic resonance (MR)) angiography showing segmental cerebral artery vasoconstriction; (b) no evidence for aneurysmal subarachnoid hemorrhage; (c) normal or near-normal findings for cerebrospinal fluid analysis (protein level \80 mg/dL, white blood cell count\10 cells/lL, normal glucose level); (d) severe, acute headache with or without additional neurological signs or symptoms; and (e) the diagnosis cannot be confirmed until reversibility of the angiographic abnormalities is documented within 12 weeks after onset and if death occurs before the follow-up examinations are completed, the autopsy rules out conditions such as vasculitis, intracranial atherosclerosis, and aneurysmal subarachnoid hemorrhage, which can also manifest with headache and stroke [3]. Here, we report transient visual hallucinations resembling the ones in CBS in a patient with RCVS. A 64-year-old woman experienced severe thunderclap headache when she was skiing. CT and MR imaging (MRI) of her brain performed at that time revealed no abnormality. MRI and magnetic resonance angiography (MRA) conducted about 3 weeks later revealed convexity subarachnoid hemorrhage in the right frontal lobe and multiple segmental cerebral artery vasoconstrictions (Fig. 1). Her blood pressure was 130/96 mmHg, her body temperature was 36.2 C, and she was alert. She had no visual loss but experienced formed and complex visual hallucination such as ‘‘people walking down the street’’ or ‘‘people acting in a theater’’ only when she closed her eyes, and she had full retention of insight. Her visual hallucinations began about 3 weeks after the onset of headache, and lasted for about a week. 99mTc-ECD single-photon emission computed tomography showed diminished blood flow in both the occipital lobes (Fig. 2). Her headache eventually resolved without any neurological deficit. MRA performed at about 5 weeks after the onset of headache showed more cerebral artery vasoconstrictions, but the vasoconstrictions resolved 2 weeks after that, and the patient was diagnosed with RCVS. Y. Yagi (&) Y. Watanabe H. Yokote T. Amino T. Kamata Department of Neurology, Musashino Red Cross Hospital, Kyonancho 1-26-1, Musashino, Tokyo 180-8610, Japan e-mail: yyagi-tmd@umin.ac.jp

Clinical correlates of olfactory hallucinations in schizophrenia

OBJECTIVES. Olfactory hallucinations (OHs) are underrepresented in conventional clinical instruments, infrequently researched, and poorly understood. To advance understanding of OHs, we examined their past-month prevalence and co-occurring symptoms in two datasets. DESIGN. One dataset comprised categorical codes and was examined using homogeneity analysis and logistic regression; the other dataset comprised numeric ratings and was examined using principal components analyses and linear regression. METHOD. The two datasets included: (1) 962 cases with Present State Examination - 9th Edition (PSE-9), codes (recoded present/absent) from the World Health Organization 10 Country (WHO-10) Study and (2) 265 cases with ratings on Scales for Assessing Positive/Negative Symptoms of Schizophrenia (SAPS/SANS). Two PSE-9 items (external- and self-smells) were recoded into a single OH item to examine consistency with the SAPS/SANS dataset, which contained a single OH item. RESULTS. Prevalence of OHs and hallucinations in other modalities differed according to the WHO-10 international centre. Across centres, OHs were present in 13% of the WHO-10 dataset, similar to the 17% prevalence rate in the SAPS/SANS dataset. Referential/control delusions and other hallucinations (particularly, somatic/tactile/gustatory hallucinations) were significant independent correlates of OHs in both datasets. OHs also co-occurred with social anxiety and depression in the WHO-10 dataset, with self-smells being particularly associated with self-depreciation. CONCLUSIONS. Sociocultural factors may modulate the self-reporting and/or detection of OHs and hallucinations in other modalities. Referential/control delusions promote the generation and/or maintenance of OHs independent of factors shared with other hallucinations. OHs and hallucinations of taste, touch, and bodily sensation frequently co-occur. Self-smells warrant sensitive probing.

Olfactory hallucinations in schizophrenia and schizoaffective disorder: A phenomenological survey

Olfactory hallucinations (OHs), so it has been argued, are prognostic of a poorer outcome, are unpleasant, and cannot be well explained within current theoretical accounts of hallucinations. We examined these and related issues by conducting structured interviews with 51 participants who experienced OHs and who were previously diagnosed with schizophrenia or schizoaffective disorder. We found no relationship between disease severity measures and type or frequency of OHs. As with prior research, we too noted the predominance of negative OHs, but with many reports of positive OHs, and also found significant relationships between frequency of OHs and severity of tactile hallucinations. We then examined whether odor imagery or involuntary memory might account for the presence of OHs, but these possibilities were not well supported. We then explored, using cluster analysis, whether or not our sample was homogenous. Two clusters were of especial interest; one which may reflect a ‘sensory dysfunction group’ and one characterized by more severe tactile hallucinations. The presence of tactile hallucinations may suggest a further novel cause of OHs, which we discuss. Our data suggest diverse causes for OHs in schizophrenia, none of which are consistent with current models of hallucinations in other modalities.

Transient Complex Visual Hallucinations With Venlafaxine Treatment

Sir: Antidepressants have been noted to cause hallucinations, often with drug overdose, but also in rare instances as a side effect at therapeutic dose.1 Bupropion, tricyclics, and selective serotonin reuptake inhibitors (SSRIs) have most often been cited as the causative agents.1 We present a case of transient complex visual hallucinations following the initiation of venlafaxine for major depressive disorder. Case report. Mr. A was a 44-year-old man recovering from alcohol dependence in an outpatient partial hospitalization program. He had been recently hospitalized for delirium tremens and was discharged 3 days before admission to our outpatient program in December 2007. He began venlafaxine treatment, 75 mg daily, for depression 2 weeks after his last drink. Before initiation of treatment, he had had no auditory or visual hallucinations for 10 days and no history of psychotic disorders or manic symptoms. He was diagnosed according to DSM-IV-TR with alcohol dependence and recurrent major depressive disorder without psychosis. Mr. A had been 3 weeks' sober when, after 1 week of venlafaxine treatment, he reported having visual hallucinations during daytime group sessions: seeing an acetylene torch in his hand and trying to strike it against his desk to light it as well as nodding his head to drop a welding shield over his face, as he did when he worked as a welder. He had insight that these were hallucinations. He had no delusions or hallucinations in other modalities, no manic symptoms, and no altered mental status. The only other side effect noted was increased vividness to his dreams. The only other medication changes were the addition of lactulose for mildly elevated ammonia, 41 μmol/L at the onset of hallucinations. After 1 week, his hallucinations resolved, and he had no repeat episodes. The venlafaxine dose was maintained throughout his treatment. He completed the outpatient program and was discharged without further incidents 3 weeks later, and at 2 monthly follow-up appointments he reported no additional hallucinations. Antidepressants have been cited as inducing hallucinations in rare cases. There have been 2 reports of venlafaxine-induced hallucinations, in an adolescent patient and an adult patient.2,3 Given that Mr. A's dose was low (75 mg daily), the assumed mechanism of action for hallucinosis is serotonergic, not norepinephrinergic. Some studies have suggested that SSRIs may induce psychotic symptoms by 5-HT2– and 5-HT3–mediated dopamine release in the ventral striatum.4 Venlafaxine may have produced visual hallucinations via dopamine release in the mesolimbic pathway by stimulation of 5-HT2 and 5-HT3 receptors. A possible interaction could have been reactivation of alcoholic hallucinosis with venlafaxine, which was reported with sertraline in 1 case by Hermann et al.5 However, the causative mechanism in that case was felt to be due to increased dopamine availability. Sertraline shows the greatest amount of dopamine reuptake inhibition of all SSRIs, while venlafaxine shows no inhibition of the dopamine reuptake transporter. Lastly, our patient's ammonia was mildly elevated, and treatment could have exacerbated a subclinical hepatic encephalopathy, although no altered mental status or other signs of delirium were observed during his partial hospitalization. Adam C. Tripp, M.D., Ph.D. Western Psychiatric Institute & Clinic, University of Pittsburgh Medical Center Scott A. Golden, M.D. Behavioral Health Division, Veterans Hospital at Highland Drive, Pittsburgh, Pennsylvania

Dementia with Lewy Bodies

Synucleinopathies, with and without dementia, encompass a wide range of diseases including Parkinson's disease, multiple system atrophy, rapid eye movement (REM) sleep behavior disorder, and dementia with Lewy bodies (DLB). DLB is a neurodegenerative disorder resulting in slowly progressive and unrelenting dementia until death. Prevalence studies suggest that it is the second most common dementing illness in the elderly. The neuropathologic findings of DLB show a wide anatomic range. Lewy bodies and Lewy-related pathology are found from the brain stem to the cortex and, in many cases, associated with concurrent Alzheimer's disease pathology. A recent international consortium on DLB has resulted in revised criteria for the clinical and pathological diagnosis of DLB incorporating new information about the core clinical features and improved methods for their assessment. The presentation of DLB is typically one of cortical and subcortical cognitive impairments, with worse visuospatial and executive dysfunction than Alzheimer's disease. There may be relative sparing of memory especially in the early stages. Core clinical features of DLB include fluctuating attention, recurrent visual hallucinations, and parkinsonism. Suggestive features include REM sleep behavior disorder, severe neuroleptic sensitivity, and low dopamine transporter uptake in the basal ganglia on functional neuroimaging. Additional supportive features that commonly occur in DLB, but with lower specificity, include repeated falls and syncope, transient, unexplained loss of consciousness, severe autonomic dysfunction, hallucinations in other modalities, systematized delusions, depression, relative preservation of medial temporal lobe structures on structural neuroimaging, reduced occipital activity on functional neuroimaging, prominent slow wave activity on electroencephalogram, and low uptake myocardial scintigraphy. Management of DLB includes pharmacological and nonpharmacological interventions for its cognitive, neuropsychiatric, motor, and sleep disturbances.

Cholinesterase inhibitors for dementia with Lewy bodies.

Dementia with Lewy bodies (DLB) was first described in 1983, and clinical diagnostic criteria were published in the early to mid 1990s. It has been suggested DLB may account for up to 15-25% of cases of dementia among people aged over 65, although autopsy suggests much lower rates. Characteristic symptoms are dementia, marked fluctuation of cognitive ability, early and persistent visual hallucinations and spontaneous motor features of Parkinsonism. Falls, syncope, transient disturbances of consciousness, neuroleptic sensitivity, and hallucinations in other modalities are also common. This combination of features can be difficult to manage as neuroleptics can make the Parkinsonian and cognitive symptoms worse. There is evidence to suggest that the cholinesterase inhibitors may be beneficial in this disorder; small case series indicate that cholinesterase inhibitors are safe, and will improve both cognitive deficits and neuropsychiatric symptoms in DLB. To assess the use of cholinesterase inhibitors in DLB. The trials were identified from a search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 25 February 2002 using the terms 'lewy body', 'Lewy bodies' and 'Lewy'. This register contains records from all major health care databases and trial databases and is updated regularly. Randomized, double-blind trials in which treatment with cholinesterase inhibitors was administered and compared with alternative interventions in patients with DLB are included. Two reviewers (TP, RW) independently assessed quality of trials according to criteria described in the Cochrane Collaboration Handbook. Each drug was to be examined separately, and together as a group. We also analysed data by time to outcome measurement; short-term (up to one month), medium term (one month up to six months) and long term (Six months and longer). The primary outcome measures of interest are in the following areas: neuropsychiatric features. i.e. psychiatric symptoms and behavioural disturbances, cognitive function, activities of daily living, global assessments, quality of life, including maintaining role and social functioning, effect on carers, safety as measured by incidence of adverse events and side effects, acceptability of treatment as measured by withdrawal from trials, and by patient/carer assessment, institutionalization and death. There was one included trial (McKeith 2000f) of rivastigmine compared with placebo on 120 patients. Neuropsychiatric InventoryThe 10-item test found no significant difference between the two groups in change of scores from baseline using intention-to-treat (ITT) analysis at 20 weeks and last observation carried forward (LOCF) analysis. The treatment effect was statistically significant in favour of rivastigmine if only observed cases (OC) were analysed (WMD -6.94, 95% CI -11.59 to -2.29, P=0.003). There were similar results for the NPI-4, with only the OC analysis showing a significant superiority of rivastigmine to placebo at 20 weeks (WMD -3.75, 95%CI -6.62 to -0.88, P=0.01).MMSE:Analysis of these results showed no statistically significant difference between the two groups at 20 weeks.CGC-plus:Analysis of the proportion of patients who had no change or became worse found no statistically significant difference between the two groups at 20 weeks for the ITT, LOCK and OC analyses. Adverse Events:The placebo group experienced significantly fewer adverse events than the treatment group (54/59 vs 46/61,OR 3.52, 95%CI 1.19 to 10.43). However, using ITT analysis of 20-week data, there was no significant difference between the two groups when serious adverse events were considered. There were no significant differences in death rates between the two groups at 20 weeks.Drop-out Rates:Analysis of these results showed no difference between the two groups at 20 weeks using ITT analysis. Patients with dementia with Lewy bodies who suffer from behavioural disturbance oS CONCLUSIONS: Patients with dementia with Lewy bodies who suffer from behavioural disturbance or psychiatric problems may benefit from rivastigmine if they tolerate it, but the evidence is weak. Further trials using rivastigmine are needed, as are trials of other cholinesterase inhibitors in dementia with Lewy bodies.

Dementia with lewy bodies--diagnosis and treatment.

Dementia with Lewy bodies (DLB) accounts for 15-20% of all autopsy confirmed dementias in old age. Characteristic histopathological changes are intracellular Lewy bodies and Lewy neurites, with abundant senile plaques but sparse neurofibrillary tangles. Core clinical features are fluctuating cognitive impairment, persistent visual hallucinations and extrapyramidal motor symptoms (parkinsonism). One of these core features has to be present for a diagnosis of possible DLB, and two for probable DLB. Supportive features are repeated falls, syncope, transient loss of consciousness, neuroleptic sensitivity, delusions and hallucinations in other modalities. DLB is clinically under-diagnosed and frequently misclassified as systemic delirium or dementia due to Alzheimer's disease or cerebrovascular disease. Therapeutic approaches to DLB can pose difficult dilemmas in pharmacological management. Neuroleptic medication is relatively contraindicated because some patients show severe neuroleptic sensitivity, which is associated with increased morbidity and mortality. Antiparkinsonian medication has the potential to exacerbate psychotic symptoms and may be relatively ineffective at relieving extrapyramidal motor symptoms. Recently there is converging evidence that treatment with cholinesterase inhibitors can offer a safe alternative for the symptomatic treatment of cognitive and neuropsychiatric features in DLB. This review will focus on the clinical characteristics of DLB, its differential diagnosis and on possible management strategies.

Dementia with lewy bodies--diagnosis and treatment.

Dementia with Lewy bodies (DLB) accounts for 15-20% of all autopsy confirmed dementias in old age. Characteristic histopathological changes are intracellular Lewy bodies and Lewy neurites, with abundant senile plaques but sparse neurofibrillary tangles. Core clinical features are fluctuating cognitive impairment, persistent visual hallucinations and extrapyramidal motor symptoms (parkinsonism). One of these core features has to be present for a diagnosis of possible DLB, and two for probable DLB. Supportive features are repeated falls, syncope, transient loss of consciousness, neuroleptic sensitivity, delusions and hallucinations in other modalities. DLB is clinically under-diagnosed and frequently misclassified as systemic delirium or dementia due to Alzheimer's disease or cerebrovascular disease. Therapeutic approaches to DLB can pose difficult dilemmas in pharmacological management. Neuroleptic medication is relatively contraindicated because some patients show severe neuroleptic sensitivity, which is associated with increased morbidity and mortality. Antiparkinsonian medication has the potential to exacerbate psychotic symptoms and may be relatively ineffective at relieving extrapyramidal motor symptoms. Recently there is converging evidence that treatment with cholinesterase inhibitors can offer a safe alternative for the symptomatic treatment of cognitive and neuropsychiatric features in DLB. This review will focus on the clinical characteristics of DLB, its differential diagnosis and on possible management strategies.

The Charles Bonnet Syndrome: A Large Prospective Study in the Netherlands

The aims were to determine the prevalence of the Charles Bonnet syndrome (CBS) in low-vision patients and analyse possible associated ophthalmic and sociodemographic factors. A semi-structured interview on visual hallucinations was given to 300 adult low-vision patients and 200 elderly general ophthalmic patients. Positive cases were examined with the Geriatric Mental State Schedule and the Mini Mental State Examination. Diagnostic criteria were as follows: complex, persistent, or repetitive visual hallucinations; full or partial retention of insight; no hallucinations in other modalities; and no delusions. Ophthalmic and sociodemographic data were gathered for all patients. The prevalence of CBS in low-vision patients was 11%. CBS was significantly associated with an age over 64 years and a visual acuity in the best eye of 0.3 or less. No significant associations with ophthalmic diagnoses, patient sex, marital status, or social circumstances were found. Our findings support association of CBS with sensory deprivation and advanced age.