Risk factors for delusion of theft in patients with Alzheimer's disease showing mild dementia in Japan

The Association Between Distinct Delusional Ideations and Depressive Symptoms in Alzheimer's Disease: A Re-Analysis of CATIE-AD

Background

Delusional ideations, one of neuropsychiatric symptoms (NPSs), are frequently shown in the long-term progression of Alzheimer's disease (AD), and comorbid with other NPSs including depression or agitation. Despite various types of delusional ideations, the comorbidity between each delusional ideation and depressive symptoms has not been discussed.

Objective

The present cross-sectional study is aimed at testing the hypothetical mechanism of comorbid pattern in AD.

Methods

Among 421 patients with AD, we analyzed the dataset of the Clinical Antipsychotic Trials of Intervention Effectiveness-Alzheimer's Disease to compare age, sex, racial type, Mini-Mental State Examination (MMSE) scores, and Neuropsychiatric Inventory (NPI) depression score of between the presence and absence of each delusional ideation (delusion of persecution, theft, jealousy, abandonment, phantom boarder, Capgras syndrome, misidentification of place, or television sign). Next, with the stratification based on MMSE score of < or > = 15 points, we further explored association between delusional ideation and depressive symptom that was found significances in the primary analysis.

Results

Among eight subtypes of delusional ideations, depression score was higher in those with persecution delusion or Capgras syndrome. Moreover, the Capgras syndrome was associated with presence of depression in severer global cognitive impairment status.

Conclusions

As comorbid NPSs of delusional ideation in AD, depressive severity is associated with specific delusional subtype: persecution delusion and Capgras syndrome. Capgras syndrome may be attributable to severe cognitive impairment in addition to depressive symptom. The consideration of pathogenetic differences in the distinct delusional ideations may be helpful for clinicians to select the treatment strategy.

Clinicodemographic and Psychosocial Factors Related to Presentation or Severity of Delusions of Theft among Females with Amnestic Mild Cognitive Impairment and Alzheimer's Disease

Objectives: We examined the clinicodemographic and psychosocial factors that relate to the presentation and severity of delusions of theft among female patients with amnestic mild cognitive impairment (a-MCI) and Alzheimer's disease (AD).Methods: We enrolled a total of 177 female patients with a-MCI or AD, of whom 40 presented with delusions of theft. We compared the differences in clinicodemographic and psychosocial factors of the 40 patients (delusions of theft group) with 50 age- and Mini-Mental State Examination (MMSE)-matched controls without delusions (control group). Furthermore, we identified the factors associated with the presentation of delusions of theft using a general linear model (GLM). The severity of delusions of theft was calculated using the Neuropsychiatric Inventory Questionnaire, and correlations between the clinicodemographic and psychosocial factors were examined.Results: Between the two groups, the delusions of theft group had lower scores on the Physical Self-Maintenance Scale and instrumental activities of daily living (IADL) and higher scores on the Japanese version of the Zarit Caregiver Burden Interview (ZBI-J) than the control group. GLM analysis revealed that the IADL score was related to the presentation of delusions of theft. The severity of delusions of theft correlated with the MMSE and the ZBI-J scores in the delusions of theft group.Conclusions: The two groups had several differences regarding clinicodemographic and psychosocial factors. Furthermore, lower IADL scores were related to symptom presentation. Symptom severity correlated with cognitive functioning and caregiver burden.Clinical Implications: In the determination of treatment or care, differences in these factors should be considered.

Sex differences in the severity of neuropsychiatric symptoms and their relationship with clinico-demographic and psychosocial factors in patients with amnestic mild cognitive impairment and mild Alzheimer's disease

Objectives: We examined differences in the severity of neuropsychiatric symptoms (NPS) according to sex and identified NPS-related clinico-demographic and psychosocial factors among community-living patients with amnestic-mild cognitive impairment (a-MCI) or mild Alzheimer's disease (AD).Method: Overall, 111 patients (44 males, 67 females) with mild a-MCI (n = 64) or mild AD (n = 47) were included. We divided the patients according to sex and compared their clinico-demographic and psychosocial factors, explored the severity of NPS using the subscales from the Neuropsychiatric Inventory-Questionnaire (NPI-Q), and further identified variables related to NPS.Results: Significant differences in several clinico-demographic and psychosocial characteristics were observed between the sexes. The severity of delusions was higher among females (mean, 0.48; SD, 1.60) than males (mean, 0.23; SD, 1.07; p = .02), while the severity of irritability was higher among males (mean, 0.97; SD, 1.92) than females (mean, 0.49; SD, 1.40; p = .03). The severity of delusions among females was related to the duration of cognitive decline (B = 0.37, p = .03), while the severity of irritability among males was related to general cognition (B = -0.40, p = .003).Conclusion: The severity of NPS among patients with a-MCI or mild AD differed according to sex. We identified NPS-related clinico-demographic factors among these patients. Sex differences should be considered when determining the need for NPS interventions.

Clinical Aspects of Neurobehavioral Symptoms of Dementia

Neurobehavioral symptoms of dementia (NBSD) are very common and are significant symptoms of the illness, contributing most to caregiver burdens and often resulting in premature institutionalization of the person with dementia. The main symptoms of NBSD are anxiety, depression, delusions, and hallucinations. NBSD produce significant problems for both patients and caregivers. The pathophysiology of NBSD is determined by genetic, structural, or environmental factors. Therefore, treatment of NBSD requires continuous and organic cooperation between patients, caregivers, social environments, and doctors. Therefore, it is important for neurologists, who mainly view NBSD for dementia patients, to increase their understanding of these more comprehensive areas as well as the latest insights and treatments to help patients and caregivers.

Understanding the Delusion of Theft

The elderly with dementing illness often present with psychotic symptoms such as delusions, but the thematic content of delusions in the elderly differs from that of delusions expressed by younger individuals, and can be pathognomonic of early dementia. The aim of this paper is to review the recent literature on the delusion of theft, the most prevalent delusion in the elderly, in order to arrive at a deeper understanding of its sources and to identify successful therapeutic approaches. The literature from 2000 to the present was searched on the Google Scholar database using relevant search terms. Several older classical papers were also referenced. Understanding the origins of the delusion of theft - multiple losses, attempts at attributing such losses to an outside source, attempts at reliving a happier past - helps in devising responses that are comforting to the patient. The distress that often accompanies the delusion of having been robbed can be decreased by nursing home improvements in the handling of personal possessions, by the correction of sensory deficits, and by the provision of activities that distract from loneliness. Attention to stimuli that trigger the delusion helps to limit its occurrence. Medications may help, but can sometimes make matters worse. Understanding that delusional thinking can arise from sensory and cognitive deficits is critical to empathic caregiving and also to the lessening of caregiver burden.

Relationship between Delusion of Theft and Cognitive Functions in Patients with Mild Alzheimer's Disease

Although delusion of theft (DT) is the most frequent type of delusion in Alzheimer's disease (AD), its relationship to cognitive functions remains unclear. The aim of this study was to demonstrate the relationship between DT and cognitive functions in mild AD. Two hundred eighty-nine mild AD patients were enrolled in this study. These subjects were classified into three groups: patients with no delusions (ND, n=82), patients with paranoid delusions (PD, n=114) and patients with DT (n=93). Cognitive functions and their associations with the degree of delusion were compared among the three groups. The results showed that verbal Fluency scores were significantly lower in the PD group than in the DT and ND groups. Word List Recall scores were significantly lower in the DT group than in the PD and ND groups. Interestingly, delusion severity measured with the Neuropsychiatric Inventory delusion subscale correlated negatively with the Word List Recall scores in the DT group. In this study, we demonstrated that episodic memory functions in mild AD patients were associated with DT, but not with PD. Further studies might be needed to clarify the pathophysiology of delusions associated with AD.

Characteristics of dementia patients who described or did not describe the relationship between two people on the COGNISTAT speech sample

Speech sample of Cognitive Status Examination (COGNISTAT) is a task in which examinees freely talk about what is happening in a presented picture. We investigated whether there are differences in the characteristics between patients who described or did not describe the relationship between two people in the speech sample based on age, gender, cognitive dysfunction, and type of dementia (Alzheimer's disease and dementia with Lewy bodies). The participants were 60-year-old or older patients diagnosed with Alzheimer's disease or dementia with Lewy bodies who undertook the Mini-Mental State Examination (MMSE) and COGNISTAT at a general hospital specialized in care for the elderly. MMSE and COGNISTAT were performed by a female clinical psychologist in all patients. In a stepwise logistic regression analysis using the two groups (description and no description groups) as a response variable, and the age, gender, diagnosis, MMSE score, and score of each COGNISTAT subtest as explanatory variables, the MMSE score (OR = 1.09; 95% CI [1.03, 1.15]) and gender (OR = 1.79; 95% CI [1.09, 2.93]) factors were extracted. These results indicated that patients with severer overall cognitive dysfunction and male patients were unlikely to describe the relationship between two people in a speech sample.

Neuropsychiatric aspects of dementia

Dementia affects approximately 6.5% of people over the age of 65. Whilst cognitive impairment is central to the dementia concept, neuropsychiatric symptoms are invariably present at some stage of the illness. Neuropsychiatric symptoms result in a number of negative outcomes for the individual and their caregivers and are associated with higher rates of institutionalization and mortality. A number of factors have been associated with neuropsychiatric symptoms including neurobiological changes, dementia type, and illness severity and duration. Specific patient, caregiver and environmental factors are also important. Neuropsychiatric symptoms can be broadly divided into four clusters: psychotic symptoms, mood/affective symptoms, apathy, and agitation/aggression. Neuropsychiatric symptoms tend to persist over time although differing symptom profiles exist at various stages of the illness. Assessment should take into account the presenting symptoms together with an appreciation of the myriad of likely underlying causes for the symptoms. A structured assessment/rating tool can be helpful. Management should focus on non-pharmacological measures initially with pharmacological approaches reserved for more troubling symptoms. Pharmacological approaches should target specific symptoms although the evidence-base for pharmacological management is quite modest. Any medication trial should include an adequate appreciation of the risk-benefit profile in individual patients and discussion of these with both the individual and their caregiver.

Psychosis of Alzheimer disease: prevalence, incidence, persistence, risk factors, and mortality

OBJECTIVES

To establish the prevalence, incidence, persistence, risk factors, and mortality risk increase of psychosis of Alzheimer disease (PoAD) in a clinical sample.

DESIGN, PARTICIPANTS, AND MEASUREMENTS

Cross-sectional, observational study of 491 patients with probable AD who, at baseline visit, were evaluated with the Cambridge Examination for Mental Disorders of the Elderly, the Neuropsychiatric Inventory-10, the Rapid Disability Rating Scale-2, and the Zarit Burden Interview. All participants were reevaluated at 6, 12, 18, and 24 months. PoAD diagnoses were made using specific criteria.

RESULTS

PoAD prevalence was 7.3%, and the cumulative incidence at 6, 12, 18, and 24 months was 5.8%, 10.6%, 13.5%, and 15.1%, respectively. After 1 year, psychotic symptoms persisted in 68.7% of the patients with initial PoAD. At baseline, patients with PoAD scored lower in the Cambridge Cognitive Examination and Mini-Mental State Examination and higher in the Rapid Disability Rating Scale-2 and Zarit Burden Interview tests. Both low scores in the Cambridge Cognitive Examination subscale of learning memory (hazard ratio [HR] = 0.874; 95% CI: 0.788-0.969; Wald χ2 = 6.515; df = 1) and perception (HR = 0.743; 95% CI: 0.610-0.904; Wald χ2 = 8.778; df = 1), and high scores in expressive language (HR = 1.179; 95% CI: 1.024-1.358; Wald χ2 = 5.261; df = 1) and calculation skills (HR = 1.763; 95% CI: 1.067-2.913; Wald χ2 = 4.905; df = 1) were found to be associated with PoAD. PoAD leads to a faster functional impairment, and it increases mortality risk (HR = 2.191; 95% CI: 1.136-4.228; Wald χ2 = 5.471; df = 1) after controlling for age, gender, cognitive and functional disability, general health status, and antipsychotic treatment.

CONCLUSIONS

PoAD seems to define a phenotype of AD of greater severity, with worsened functional progression and increased mortality risk.

Classification of delusions in Alzheimer's disease and their neural correlates

BACKGROUND

Previous findings on neural correlates of delusion in Alzheimer's disease (AD) have been inconsistent because of methodological issues, such as treating multiple delusions as a single entity. In this retrospective study, we classified AD delusions and investigated their neural correlates by using single-photon emission computed tomography data.

METHODS

We selected AD patients with delusions from our consecutive outpatients from 2004 to 2010. In this study, eight types of delusions were evaluated with Neuropsychiatric Inventory and classified by factor analysis. Twenty-five of the patients also had single-photon emission computed tomography data, which we used to assess the relationships between cerebral regions of hypoperfusion and hyperperfusion and each classified delusion. The relations were assessed using Statistical Parametric Mapping with normalization to the white matter cerebral blood flow.

RESULTS

The delusions were classified into three factors. Factor 1 consisted of a belief that his/her house is not his/her home, phantom boarder symptom, delusion of abandonment, and belief that one's spouse or others are not who they claim to be. Factor 1 was related to hypoperfusion in the right temporal pole and hyperperfusion in the medial frontal and precentral regions. Factor 2 consisted of delusion relating to the television and delusion of persecution. Factor 2 was related to hypoperfusion in the precuneus and hyperperfusion in the insula and thalamus. Factor 3 consisted of delusion of abandonment and delusional jealousy. Factor 3 was related to hypoperfusion in the right inferior temporal and frontal regions and hyperperfusion in the middle frontal gyrus, insula and posterior cingulate gyrus. Delusion of theft was not included in any factors, and it was related to hypoperfusion in the bilateral thalami and left posterior cingulate gyrus and hyperperfusion in the left inferior frontal regions and anterior cingulate gyrus.

CONCLUSIONS

Delusions in AD were classifiable, and each classified delusion was related to different neural networks.

Origins of delusions in Alzheimer's disease

Research over the past two decades supports a shared aetiology for delusions in Alzheimer's disease (AD) and schizophrenia. Functional networks involved in salience attribution and belief evaluation have been implicated in the two conditions, and striatal D2/3 receptors are increased to a comparable extent. Executive/frontal deficits are common to both disorders and predict emergent symptoms. Putative risk genes for schizophrenia, which may modify the AD process, have been more strongly implicated in delusions than those directly linked with late-onset AD. Phenotypic correlates of delusions in AD may be dependent upon delusional subtype. Persecutory delusions occur early in the disease and are associated with neurochemical and neuropathological changes in frontostriatal circuits. In contrast, misidentification delusions are associated with greater global cognitive deficits and advanced limbic pathology. It is unclear whether the two subtypes are phenomenologically and biologically distinct or are part of a continuum, in which misidentification delusions manifest increasingly as the pathological process extends. This has treatment implications, particularly if they are found to have discrete chemical and/or pathological markers.

Neurobiology of delusions in Alzheimer's disease

Alzheimer's disease (AD) is associated with cognitive and functional impairment as well as neuropsychiatric sequelae, including psychotic symptoms such as delusions and hallucinations. Strong evidence supports the need to study delusions separate from hallucinations. Integrating the epidemiology, clinical correlates, and neuropathological and genetic literature for delusions in AD allows us to speculate on etiology and mechanisms. Plaque and tangle deposition in individuals with susceptible alleles of serotonergic, muscarinic, nicotinic, or Apoε4 genes appears to result in disruption of cortical circuitry, culminating in delusions. While delusions in AD correspond to a phenotype distinct from AD without delusions, subtypes of delusions may also define further distinct clinical entities. Persecutory delusions may occur earlier in the illness and have a more significant genetic component than misidentification delusions, which are associated with increased cognitive impairment and advanced dementia. Clearly distinguishing between these two syndromes is essential to making progress in the area of delusions in AD.