Phenomenology and clinical correlates of delusions in Alzheimer disease.

OBJECTIVES: The objectives of this study were to determine whether anosognosia, depression, and elevated mood are associated with delusions in Alzheimer disease (AD), and to examine the validity of standardized diagnostic criteria for psychosis of dementia. METHOD: The authors assessed a consecutive series of 771 patients with AD attending a dementia clinic with a comprehensive neuropsychologic and psychiatric evaluation that included specific measures of delusions, hallucinations, anosognosia, depression, and elevated mood. RESULTS: Delusions were found in one-third of the patients and hallucinations in 7%. Most patients with hallucinations also had delusions. A principal component analysis of the Psychosis Dementia Scale, which rates the presence and severity of delusions, produced the factors of paranoid misidentification and expansive delusions. Paranoid, but not expansive, delusions increased across the stages of the illness. Anosognosia and depression were significantly and independently associated with the presence of delusions, whereas elevated mood was significantly associated with expansive, but not paranoid, delusions. A multiple logistic regression analysis demonstrated that delusions in AD were significantly associated with depression, anosognosia, overt aggression, and agitation. CONCLUSIONS: Anosognosia, depression, global cognitive deficits, and elevated mood are the main psychiatric correlates of paranoid misidentification and expansive delusions in AD, whereas overt aggression and agitation are the most frequent behavioral concomitants of psychosis in AD.     

Psychosis in a pediatric mood and anxiety disorders clinic: phenomenology and correlates

OBJECTIVES: To examine the demographics and phenomenology of psychosis in a sample of children and adolescents referred to a mood and anxiety disorders clinic. METHOD: Patients (N = 2,031) were assessed with the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present Episode version and classified as definite, probable, or nonpsychotic. Clinical and demographic characteristics of the groups were compared,and symptoms of psychosis were analyzed using factor analysis. RESULTS: Definite psychotic symptoms were seen in approximately 90 (4.5%) patients: 80% of these reported hallucinations (mainly auditory), 22% delusions, and 3.3% thought disorder. Of the patients with definite psychotic symptoms, 24% had bipolar disorder, 41% had major depression, 21% had subsyndromal depression, and 14% had schizophrenia spectrum disorders (schizophrenia and schizoaffective disorders). Factor analysis of the definite psychotic symptoms yielded 4 factors: hallucinations, thought disorder, delusions, and manic thought disorder. Psychotic patients had a higher frequency of comorbid disorders and suicidal ideation than nonpsychotic patients. CONCLUSIONS: Outpatient youngsters with mood disorders frequently present with psychotic symptoms, in particular auditory hallucinations. These patients commonly have comorbid psychiatric disorders and suicidal ideation.     

Psychoses in patients with Parkinson's disease; their frequency, phenomenology, and clinical correlates]

The frequency, phenomenology, and risk factors of hallucinations and delusions were investigated in 64 consecutive inpatients with Parkinson's disease. Fifty patients were admitted to our hospital with symptoms related to Parkinson's disease: psychiatric problems 27 (psychosis 22; anxiety 2; depression 2; mania 1): motor symptoms, 20 (wearing-off 5; akinesia 4; freezing 4; postural instability 4; dyskinesia 2; tremor 2; dystonia 1), and sensory symptoms, 3. Fourteen patients were admitted with other medical problems (pneumonia 4; cerebral infarction 3; bone fracture 3; lumbago 2; seizure 1; cat bite 1). Totally 49 patients had psychiatric problems. Psychosis was present in 43 patients, dementia in 10, depression in 8, mania in 1, anxiety in 10, agitation in 6, stereotypy in 2, and hypersexuality in 2. Of the 43 patients with psychoses, 40 presented with visual hallucinations, 18 with auditory hallucinations, and 23 with delusions. To determine what the clinical correlates with the severity of psychosis were, we divided the patients into 3 groups: the severe group, 22 patients admitted because of psychotic symptoms; the mild group, 21 patients admitted because of problems other than psychosis but presenting psychotic symptoms; and the control group, 21 patients who had no psychotic symptoms. Incidences of auditory hallucinations and delusions were higher in the severe group as compared to the mild group. Patients in the severe group had higher Hoehn-Yahr stages, lower Mini-Mental State Examination scores, decreased H/M ratios of cardiac 123I-MIBG uptake, and lower frequencies of background activity on electroencephalograms. There were no differences in age at admission, age at onset of Parkinson's disease, duration of illness, amounts of levodopa and dopamine agonists received, Hamilton's depression rating scores, and brain MR findings, including atrophy and ischemic changes. Emergence of psychotic symptoms in parkinsonian patients appears to be clearly associated with impaired cognitive function. Therefore, it may be associated with the disease process itself. Terms such as dopaminomimetic or levodopa-induced psychosis may not be appropriate when describing psychosis in Parkinson's disease.     

Emotion and psychosis: links between depression, self-esteem, negative schematic beliefs and delusions and hallucinations

BACKGROUND: The role of emotion in psychosis is being increasingly recognised. Cognitive conceptualisations of psychosis (e.g. [Garety, P.A., Kuipers, E.K., Fowler, D., Freeman, D., Bebbington, P.E., 2001. A cognitive model of the positive symptoms of psychosis. Psychological Medicine, 31, 189-195]) emphasise a central, normal, direct and non-defensive role for negative emotion in the development and maintenance of psychosis. This study tests specific predictions made by Garety et al. [Garety, P.A., Kuipers, E.K., Fowler, D., Freeman, D., Bebbington, P.E., 2001. A cognitive model of the positive symptoms of psychosis. Psychological Medicine, 31, 189-195] about the role of emotion and negative evaluative beliefs in psychosis. METHODS: 100 participants who had suffered a recent relapse in psychosis were recruited at baseline for the Prevention of Relapse in Psychosis (PRP) trial. In a cross-sectional analysis, we examined the role of depression, self-esteem and negative evaluative beliefs in relation to specific positive symptoms (persecutory delusions, auditory hallucinations and grandiose delusions) and symptom dimensions (e.g. distress, negative content, pre-occupation and conviction). RESULTS: Analysis indicated that individuals with more depression and lower self-esteem had auditory hallucinations of greater severity and more intensely negative content, and were more distressed by them. In addition, individuals with more depression, lower self-esteem and more negative evaluations about themselves and others had persecutory delusions of greater severity and were more pre-occupied and distressed by them. The severity of grandiose delusions was related inversely to depression scores and negative evaluations about self, and directly to higher self-esteem. CONCLUSIONS: This study provides evidence for the role of emotion in schizophrenia spectrum-disorders. Mood, self-esteem and negative evaluative beliefs should be considered when conceptualising psychosis and designing interventions.     

Prevalence and clinical correlates of psychotic symptoms in Parkinson disease: a community-based study.

BACKGROUND: Hallucinations and delusions are frequent in patients with Parkinson disease (PD) and may have severe clinical consequences for those patients and their caregivers. However, the prevalence and clinical features of these symptoms have not been studied in a representative sample. OBJECTIVE: To study the prevalence and clinical correlates of psychosis in a population-based sample of patients with PD. METHOD: Total ascertainment of patients with PD in a defined geographical area in Norway was attempted through a detailed community study. Clinical evaluation consisted of a neurologic examination and assessments of depression and cognition. Psychosis was assessed with the thought disorder subscale of the Unified Parkinson's Disease Rating Scale. RESULTS: A total of 245 patients with PD were identified, 235 (95.9%) of whom participated in this study. Twenty-three patients (9.8%) had hallucinations with insight retained, and another 14 patients (6.0%) had more severe hallucinations or delusions. Psychotic symptoms were associated with age, stage and diagnostic subgroup of PD, severity of depression, and cognitive impairment. Type, duration, and dose of antiparkinson drug therapy did not differ between those patients with PD who had or did not have psychosis. In a polychotomous logistic regression analysis, severity of depression, cognitive impairment, and impairment of activities of daily living were the only significant concomitants of psychosis. CONCLUSIONS: Hallucinations and delusions are common in patients with PD. More advanced and widespread brain changes seem to increase the risk for developing psychosis in patients with PD receiving levodopa therapy.     

Prevalence and clinical correlates of psychotic symptoms in Alzheimer's disease

Psychotic symptoms occur commonly in Alzheimer's disease (AD), predict a more rapid rate of cognitive decline and increase the risk of aggressive behaviour. Seventy patients with probable AD, recruited from an old age psychiatry service, were assessed to determine the prevalence and clinical correlates of delusions and hallucinations. Psychiatric symptoms were measured using the Behavioural Pathology in Alzheimer's Disease Rating Scale (BEHAVE-AD), Hamilton Rating Scale for Depression (HRSD) and the Depressive Signs Scale (DSS). Thirty-four per cent of the sample experienced delusions and 11% hallucinations in the previous month. Men were more likely than women to have experienced psychotic symptoms. Psychotic and non-psychotic groups did not differ in age, age at illness onset, dementia severity, HRSD or DSS scores. This study confirms the high prevalence of psychotic symptoms in AD patients encountered in clinical practice, and suggests that psychosis and depression represent independent behavioural disturbances in AD. © 1998 John Wiley & Sons, Ltd.     

Psychosis in Parkinson's disease without dementia: Common and comorbid with other non‐motor symptoms

Psychosis in Parkinson's disease (PD) is common and associated with a range of negative outcomes. Dementia and psychosis are highly correlated in PD, but the frequency and correlates of psychosis in patients without cognitive impairment are not well understood. One hundred and ninety‐one non‐demented PD patients at two movement disorders centers participated in a study of neuropsychiatric complications in PD and completed a detailed neurological and neuropsychiatric assessment, including the rater‐administered Parkinson Psychosis Rating Scale for hallucinations, delusions, and minor symptoms of psychosis (illusions and misidentification of persons). Psychotic symptoms were present in 21.5% of the sample. Visual hallucinations were most common (13.6%), followed by auditory hallucinations (6.8%), illusions or misidentification of people (7.3%), and paranoid ideation (4.7%). Visual hallucinations and illusions or misidentification of people were the most common comorbid symptoms (3.1%). Depression (P = 0.01) and rapid eye movement behavior disorder symptoms (P = 0.03) were associated with psychosis in a multivariable model. The odds of experiencing psychotic symptoms were approximately five times higher in patients with comorbid disorders of depression and sleep‐wakefulness. Even in patients without global cognitive impairment, psychosis in PD is common and most highly correlated with other non‐motor symptoms. Screening for psychosis should occur at all stages of PD as part of a broad non‐motor assessment. In addition, these findings suggest a common neural substrate for disturbances of perception, mood, sleep‐wakefulness, and incipient cognitive decline in PD. © 2012 Movement Disorder Society     

A study of premorbid personality and behavioural and psychological symptoms of dementia in nursing home residents

OBJECTIVE: to investigate the relationship between pre-morbid personality and behavioural and psychological symptoms of dementia (BPSD). METHODS: we studied 58 subjects with dementia and depression and/or psychosis residing in 11 Sydney nursing homes cross-sectionally. Informal caregivers completed ratings of residents' pre-morbid personality on the NEP Five-Factor Inventory (NEO-FFI). Information on BPSD was obtained using the BEHAVE-AD. RESULTS: higher neuroticism was predictive of delusions; higher agreeableness of hallucinations, aggressiveness, affective disturbance and overall behavioural disturbance; and higher openness of affective disorder. CONCLUSION: our findings are inconsistent with previous research and clinical experience. Prospective studies are needed to clarify the association between personality and behavioural disturbance in dementia.     

Intracranial mass lesions associated with late-onset psychosis and depression

Tumors and other mass lesions of the brain may present with symptoms resembling psychosis or depression or with features of delusions, hallucinations, mania, or catatonia. There is an over-representation of tumors affecting the frontal lobe, temporal lobe, and diencephalon in patients with these manifestations. Neurologic symptoms and signs may be helpful in making an early diagnosis of the tumor. Patients with late-onset psychosis, unusual histories of depression, and those with focal neurologic findings associated with psychotic disorders should undergo computerized tomographic (CT) scanning to exclude a focal brain lesion.     

The epidemiology of psychosis in dementia.

OBJECTIVE: Authors compared delusions, hallucinations, and misidentification delusions in Alzheimer disease (AD) and vascular dementia (VaD) patients. METHODS: The authors report data on the prevalence, severity, clinical, and demographic associations of these symptoms in a population sample of 260 persons with dementia, examined with the Neuropsychiatric Inventory. RESULTS: The primary finding was that there was no difference in psychosis as a whole, or in delusions and hallucinations, between AD and VaD. Also, in AD, female gender appeared to be a risk factor for delusions; subjects in an earlier stage of dementia showed fewer delusions. CONCLUSION: The profile of delusions and hallucinations seen is different from that seen in schizophrenia, further supporting the hypothesis that AD-associated psychosis is a distinct phenomenological syndrome.     

Understanding suicidal ideation in psychosis: findings from the Psychological Prevention of Relapse in Psychosis (PRP) trial

OBJECTIVE: To examine the clinically important phenomenon of suicidal ideation in psychosis in relation to affective processes and the multidimensional nature of hallucinations and delusions. METHOD: In a cross-sectional study of 290 individuals with psychosis, the associations between level of suicidal ideation, affective processes, positive symptoms, clinical and demographic variables were examined. RESULTS: Forty-one per cent of participants expressed current suicidal ideation. Suicidal ideation was associated with depressed mood, anxiety, low self-esteem, negative illness perceptions, negative evaluative beliefs about the self and others and daily alcohol consumption. Frequency of auditory hallucinations and preoccupation with delusions were not associated with suicidal ideation; however, positive symptom distress did relate to suicidal thoughts. CONCLUSION: Affective dysfunction, including distress in response to hallucinations and delusions, was a key factor associated with suicidal ideation in individuals with psychotic relapse. Suicidal ideation in psychosis appears to be an understandable, mood-driven process, rather than being of irrational or 'psychotic' origin.     

The Unified Parkinson's Disease Rating Scale: validation study of the mentation, behavior, and mood section.

The objective of this study was to examine the validity of the mentation, behavior, and mood items included in Part I of the Unified Parkinson's Disease Rating Scale (UPDRS) and to assess its usefulness to screen for dementia, psychosis, depression, and apathy. A consecutive series of 168 patients with PD were assessed by neurologists with the UPDRS, and by psychiatrists using a comprehensive neuropsychiatric evaluation blind to each other's ratings. ROC analysis demonstrated that a score of 2 or greater on the intellectual impairment item of the UPDRS had 60% sensitivity and 92% specificity to detect dementia, as diagnosed with DSM-IV criteria. When a score of 23 or lower on the MMSE was included as an additional classification variable, the sensitivity increased to 85%. A score of 2 or greater on the thought disorder item had 43% sensitivity and 92% specificity to detect psychotic symptoms (delusions or hallucinations). A score of 2 or greater on the depression item had 77% sensitivity and 82% specificity to detect major depression as diagnosed with DSM-IV criteria. Finally, a score of 2 or greater on the motivation/initiative item had 73% sensitivity and 65% specificity to detect apathy, as diagnosed with a standardized criteria. When the sample was divided into mild (i.e. Hohen-Yahr stages I and II) versus moderate-severe PD (i.e. Hohen-Yahr stages III-V), findings remained unchanged, except that the UPDRS show unacceptably low accuracy to detect psychosis in mild PD. The mentation, behavior, and mood section of the UPDRS is an adequate screen for depression and apathy, and has adequate sensitivity to detect dementia when combined with the Mini-Mental State Exam, but has low sensitivity to detect psychosis.     

Neuropsychiatric symptoms in the dementias

PURPOSE OF REVIEW: Neuropsychiatric, or non-cognitive symptoms are increasingly recognized as manifestations of dementias. RECENT FINDINGS: In Alzheimer's disease, recent advances have included the identification of behavioral profiles, differentiation of apathy and depression, characterization of risk factors for psychosis and its links to agitation and aggression, and an analysis of depressive symptoms in the absence of major depression. Functional neuroimaging data mainly supported the role of the anterior cingulate in apathy. The orbitofrontal and anterior cingulate tangle burden were associated with agitation, and increased orbitofrontal and mid-temporal muscarinic M2 receptors with psychosis and hallucinations. Selected genetic polymorphisms of dopamine and serotonin receptors or transporters were linked with aggression, hallucinations or psychosis. When compared with other dementias, individuals with frontotemporal dementia disclosed, as expected, different behaviors and particularly aberrant social behavior. The frequency of delusions and visual hallucinations was increased in Parkinson's disease, Parkinson's disease with dementia, and dementia with Lewy bodies, suggesting common mechanisms such as Lewy body pathology and cholinergic deficiency. The latter was supported by an improvement of these symptoms by cholinesterase inhibitors. SUMMARY: Future research directions include both clinical and basic neuroscience investigations. The detection of early neuropsychiatric symptoms might be a marker for dementia, and the possible existence of a mild neuropsychiatric impairment syndrome should be explored. More longitudinal studies with pathological confirmation will facilitate correlations with neuropsychiatric symptoms. Functional neuroimaging and behavioral neurogenetics will permit in-vivo correlations and consequently help patient management and care.     

Psychosocial correlates of late-onset psychosis: life experiences, cognitive schemas, and attitudes to ageing

BACKGROUND: Psychosis with first onset after the age of 60, and arising in the absence of dementia or primary affective disorder, is thought to affect 2-4% of older people, and as many as half will not respond fully to medication. AIMS: This study represents a preliminary attempt to explore a number of possible psychosocial correlates of late-onset psychosis with potential relevance for a cognitive-behavioural formulation and for the development of psychosocial interventions for this group. METHODS: The nature and extent of adverse early life experiences, presence of maladaptive cognitive schemas, and morale in relation to ageing were compared for older people with a diagnosis of late-onset psychosis (LOP; n = 14) or late-onset depression (DEP; n = 13) and healthy older volunteers (HEV; n = 18) in a cross-sectional design. RESULTS: Both LOP and DEP groups reported significantly higher levels of adverse life experiences than the HEV group, with between-group differences in the types of experiences described. The LOP group scored significantly higher than the HEV group on four out of five schema domains, and significantly higher than the DEP group on two domains, other-directedness and over-vigilance/inhibition. The LOP group had significantly lower overall morale in relation to ageing than the HEV group, reflecting significantly higher levels of lonely-dissatisfaction. CONCLUSIONS: Life experiences, cognitive schemas and attitudes to ageing are important psychosocial correlates of LOP. These findings contribute to an understanding of the emotional world of individuals who develop psychosis in later life and may have implications for developing more effective intervention approaches.     

Relationship between hallucinations, delusions, and rapid eye movement sleep behavior disorder in Parkinson's disease.

Psychotic symptoms are the main and the most disabling "nonmotor" complications of Parkinson's disease (PD), the pathophysiology of which is poorly recognized. Polysomnographic studies have shown a relationship between visual hallucinations and rapid eye movement (REM) sleep. The objective of this study is to clarify the relationship between psychotic symptoms and REM sleep behavior disorder (RBD) in PD. In a Parkinson's disease outpatient unit, 289 consecutive subjects with idiopathic PD were administered (in the period from January to December 2002) a multiple-choice questionnaire and structured interview on sleep and mental disorders. RBD was diagnosed in accordance with the minimal diagnostic criteria of the International Classification of Sleep Disorders. Hallucinations and delusional disorders were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders-IV criteria. The presence or absence of psychotic symptoms, of RBD, and of daytime sleepiness, as well as motor status, cognitive status, and mood were assessed. Approximately 32% (n = 92) of the subjects presented with psychotic disorders; 30% (n = 86) had experienced hallucinations; 2% (n = 6) had delusions without hallucinations. Sixty-two (72%) hallucinators reported nocturnal hallucinations. A total of 6.6% (n = 19) of the subjects complained of a delusional disorder. There were 26.6% (n = 77) of subjects who presented with RBD: 28 (36%) with onset before and 49 (63%) with onset after PD diagnosis. The presence of RBD was associated with an increased risk of manifesting hallucinations and delusions (odds ratio [OR], 2.73). Other independent clinical factors found to have an effect on psychotic disorders were cognitive impairment (OR, 3.92), disease duration (OR, 2.46), advanced age (OR, 2.34), and severity of motor symptoms (OR, 2.06). These results suggest that RBD is widely associated with psychosis in PD.     

Symptoms of Depression,Positive Symptoms of Psychosis,and Suicidal Ideation Among Adults Diagnosed With Schizophrenia Within the Clinical Antipsychotic Trials of Intervention Effectiveness

Suicide is among leading causes of death for adults diagnosed with schizophrenia. While symptoms of depression are consistently supported factors involved in suicidal ideation, findings on the role of positive symptoms of psychosis have been mixed with limited understandings of risk. Accordingly, this study aimed to identify the pathways of influence between symptoms of depression, positive symptoms of psychosis (i.e. hallucinations and delusions), and suicidal ideation. Data were obtained from the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE; n = 1,460). Suicidal ideation and symptoms of depression were measured by the Calgary Depression Scale (CDRS) and hallucinations and delusions by the Positive and Negative Syndrome Scale (PANSS). The data were analyzed using Structural Equation Modeling (SEM). As symptoms of depression and positive symptoms of psychosis independently increased, on average there were associated increases in suicidal ideation. The present study provides support for the relationship between positive symptoms of psychosis, specifically hallucinations and delusions, and suicidal ideation. Future prospective longitudinal study designs are needed to further increase understandings of the roles that hallucinations, delusions, and additional symptoms of schizophrenia play in both suicidal ideation and attempt to ultimately inform evidence-based interventions aiming to reduce suicidal death.     

Epidemiology of and risk factors for psychosis of Alzheimer's disease: a review of 55 studies published from 1990 to 2003

OBJECTIVE: The authors reviewed studies published between 1990 and 2003 that reported the prevalence, incidence, and persistence of, as well as the risk factors associated with, psychosis of Alzheimer's disease. METHOD: PubMed and PsycINFO databases were searched by using the terms "psychosis and Alzheimer disease" and "psychosis and dementia." Empirical investigations presenting quantitative data on the epidemiology of and/or risk factors for psychotic symptoms in Alzheimer's disease were included in the review. A total of 55 studies, including a total of 9,749 subjects, met the inclusion criteria. RESULTS: Psychosis was reported in 41% of patients with Alzheimer's disease, including delusions in 36% and hallucinations in 18%. The incidence of psychosis increased progressively over the first 3 years of observation, after which the incidence seemed to plateau. Psychotic symptoms tended to last for several months but became less prominent after 1 year. African American or black ethnicity and more severe cognitive impairment were associated with a higher rate of psychosis. Psychosis was also associated with more rapid cognitive decline. Some studies found a significant association between psychosis and age, age at onset of Alzheimer's disease, and illness duration. Gender, education, and family history of dementia or psychiatric illness showed weak or inconsistent relationships with psychosis. CONCLUSIONS: Psychotic symptoms are common and persistent in patients with Alzheimer's disease. Improved methods have advanced the understanding of psychosis in Alzheimer's disease, although continued research, particularly longitudinal studies, may unveil biological and clinical associations that will inform treatments for these problematic psychological disturbances.     

Delusion symptoms are associated with ApoE ε4 allelic variant at the early stage of Alzheimer''s disease with late onset

Alzheimer's disease (AD) is a neurodegenerative disorder with mixed cognitive and behavioural clinical manifestations. The possession of apolipoprotein-E (ApoE) epsilon4 allelic variant is one of the most important risk factors for developing late-onset AD (LOAD). In this study we analysed the relationship between the entire range of behavioural symptoms, cognitive deficit, and sociodemographic characteristics and ApoE epsilon4 allele possession with multivariate logistic regression models in LOAD patients. Patients included (n = 171) were consecutively admitted in a memory clinic for the first diagnostic visit. Levels of behaviour and cognition within the last month were assessed by the Neuropsychiatric Inventory and Mini Mental State Examination. Presence of clinically significant psychosis, delusions and hallucinations at the early stage of the illness, from the onset to the first visit, was measured with diagnostic criteria. ApoE epsilon4 allele possession was associated with increased levels of delusions within the last month from the first visit (OR 1.23; 95% CI 1.01-1.50; P < 0.05) and with the presence of categorical delusions at the early stage until the first visit (OR 3.11; 95% CI 1.21-8.01; P < 0.02). In this study, which considers the entire range of behavioural expressions in LOAD patients at the early stage of the illness, the relationship between behaviour and ApoE epsilon4 allele is confirmed for delusions only.     

Risk factors for dementia, depression and psychosis in long-standing Parkinson's disease

Summary. Objectives. To study the relationships between clinical features of Parkinson's disease (PD) and the development of dementia, depression or psychosis in patients with long-standing disease. Background. The natural history of dementia and depression in PD, and its relation to psychosis in long standing PD, are unclear. Method. 172 consecutive patients (99 men and 73 women, mean age at symptoms onset 58.3 ± 13.2 years) with 5 years or more of PD (mean symptom duration of 11.8 ± 5.6 years) were studied. Clinical data were collected during the last office visit through physical examination, detailed history, review of patient charts and outside documents. Dementia and depression were diagnosed according to DSM-IV criteria, while psychosis was diagnosed if hallucinations or delusions were present. Chi-square and t tests were used to compare the patient characteristics among those with vs. those without mental complications of the disease at different disease stages. Logistic regression was used for the comparison of associations between the presence of dementia or depression (dependent variable) and age at onset of PD, duration of PD and disease staging (explanatory variables). Results. The study population consisted of 45 patients at Hoehn & Yahr (H&Y) stage ≤2.5 (26%), 104 patients at stage 3 (60.5%) and 23 patients at H&Y stage 4–5 (13.5%). Sixty one patients (36%) had dementia, 55 patients had depression (33%) and 50 patients (27%) had psychosis. Dementia and depression were significantly associated with disease severity as reflected in the H&Y scale (P = 0.0003, Z = 3.59; P = 0.006, Z = 3.22, respectively). These associations were significant also for the older age of PD onset (≥59 years n = 89) subgroup (p = 0.001, Z = 3.2 for dementia and p = 0.02, Z = 2.9 for depression), but not for younger onset cases (<59 years n = 83). Dementia was significantly associated with older age of PD onset (β = 0.04, p = 0.009) while depression was inversely associated with age of PD onset (β = −0.04, p = 0.02). The presence of dementia was also significantly associated with depression (β = 1.49, p = 0.0006). Dementia and depression were found to be independent explanatory variables for the development of psychosis (logistic regression, odds ratio (OR) = 26.0, p < 0.0001; OR = 10.2, p < 0.0001, respectively). In patients with younger age of PD onset, depression more than dementia was strongly correlated with the appearance of psychosis. Conclusion. Dementia in PD was related to older age of symptoms onset and old age. Depression was associated with dementia or early age of PD onset. Depression seemed to contribute to the appearance of psychosis even more than dementia, especially in patients with younger age of symptoms onset. Received January 28, 1999; accepted June 30, 1999