Sleep disorders in patients with Parkinson's disease: epidemiology and management.

Patients with Parkinson's disease can experience a number of sleep disorders, including insomnia, parasomnias and daytime somnolence [specifically, excessive daytime sleepiness (EDS) and sleep attacks]. Insomnia is a frequent and important complaint of patients with the disease. Both the pathology of Parkinson's disease and dopaminergic drugs may contribute to the much higher than expected frequency of sleep fragmentation and disrupted sleep among these patients. In addition, coexisting depression seems to be a major and frequent risk factor for insomnia in Parkinson's disease. After recognising a sleep problem, the first step in management is to examine and diagnose the type of insomnia and possible medical or psychological factors that may disturb nocturnal sleep. The next step is to give the patient appropriate advice on sleep hygiene. Increasing the dosage of dopaminergic drug treatment will often increase sleep disruption and should be avoided unless the patient's sleep is primarily disturbed by the motor manifestations of parkinsonism during the night. Depression should be looked for and if appropriate be treated in any patients with insomnia. If it becomes necessary to treat the patient with an hypnosedative agent, it is important to use a drug with a short half-life and that manifests as few adverse effects as possible the next morning. Up-to-date guidelines for the use of hypnosedatives should be followed. Patients with Parkinson's disease experience a wide range of parasomnias. The majority of behaviours may be related to rapid eye movement (REM) sleep behaviour disorder (RBD) or to a spectrum of symptoms ranging from vivid dreaming to psychosis. RBD is effectively treated with clonazepam. In addition, the atypical antipsychotics have given physicians new and better treatment options for psychotic symptoms in individuals with Parkinson's disease. EDS is common in Parkinson's disease, while sleep attacks seem to be rare manifestations of the disease or its treatment. Significant EDS is found in 15% of patients with Parkinson's disease compared with in 1% of healthy elderly people. Sleep attacks are observed in patients treated with all dopaminergic medications but have recently been brought to prominence because of their association with the newer dopamine agonists ropinirole and pramipexole. Patients with Parkinson's disease should be informed about the possibility of developing sleep problems during the day when prescribed new drugs. Appropriate actions with regard to driving must be taken if significant and persistent daytime somnolence or sleep attacks appear.

Health related quality of life in Parkinson's disease: a prospective longitudinal study.

OBJECTIVES: To examine the change over time in health related quality of life (HRQL) in a community based cohort of patients with Parkinson's disease. METHODS: One hundred and eleven patients were evaluated for HRQL in 1993 and then again in a follow up study 4 years later. The patients included in the study in 1993 were derived from a prevalence study of patients with Parkinson's disease in the county of Rogaland, Norway. The HRQL was measured by the Nottingham health profile (NHP). At both evaluations clinical and demographic variables were determined during semistructured interviews and by clinical examinations by a neurologist. RESULTS: During the 4 year follow up period there was a significant increase in NHP scores, reflecting a decreased HRQL, in the dimensions of physical mobility, emotional reactions, pain, and social isolation. In the same time period mean total NHP score increased from 120.0 (SD 102.6) to 176.0 (SD 119.4) (p<0.01). There were no clinical or demographic factors found in 1993 that identified patients at higher risk for developing decreased HRQL. Increased UPDRS score (unified Parkinson's disease rating scale) and Hoehn and Yahr stage during the 4 year study period correlated with increased NHP scores. Even though there was no increase in depressive symptoms or self reported insomnia, these symptoms, together with lower Schwab and England score, were the most important factors for a poor HRQL in 1997. CONCLUSIONS: Parkinson's disease has a substantial impact on HRQL. Despite modern care, we found a significantly increased distress during the 4 year follow up period. Increased parkinsonism, measured by UPDRS and Hoehn and Yahr stage, correlated with increased stress, not only in the dimension of physical mobility, but also in the areas of pain, social isolation, and emotional reactions. In addition to the clinical examination, HRQL scoring provides valuable information on the total health burden of Parkinson's disease in both cross sectional and longitudinal evaluations, and contributes to a more comprehensive picture of the total disease impact.

Clinical problems in non-fluctuating patients with Parkinson's disease: a community-based study.

OBJECTIVE: To investigate the frequency of nonfluctuators in a community-based prevalence study of Parkinson's disease (PD) and to describe disability, non-motor problems, and health-related quality of life in patients with PD with and without motor fluctuations, and compare the findings to those of two control groups. METHODS: The study involved 245 patients with PD who were participating in a prevalence study and two control groups (100 healthy elderly individuals and 100 patients with diabetes mellitus [DM]). Data were obtained through neurologic examination and a semistructured interview, and by the use of several questionnaires. RESULTS: In this group of unselected patients with PD, 78% did not experience motor fluctuations. Mean duration of treatment with levodopa was 6.3 years. Patients with motor fluctuations had a lower age at onset of disease, longer duration of disease, and a higher daily levodopa dose than patients without fluctuations. Among the non-fluctuating patients, we found more dementia and a higher age at prevalence day. Disability (assessed by the Unified Parkinson's Disease Rating Scale subscales for activities of daily living and motor function and the Hoehn and Yahr stage) was similar in fluctuators and nonfluctuators. Depression, sleep disturbances, and fatigue were equally frequent in both patient groups. The occurrence of these difficulties was clearly more frequent among non-fluctuating patients with PD than among the control subjects. CONCLUSION: Most patients in the general population who have PD do not experience dose-dependent motor fluctuations. Severity of motor disability and neuropsychiatric manifestations are as important in non-fluctuators as in fluctuators. Patients without motor fluctuations have more depression, sleep disturbances, fatigue, and a poorer health-related quality of life than patients with DM and healthy elderly individuals. This also underlines the importance of developing better management and treatment strategies for this group of patients with PD.

Predictors of nursing home placement in Parkinson's disease: a population-based, prospective study.

OBJECTIVES: To examine the rate and predictors of nursing home placement in patients with Parkinson's disease. DESIGN: Four-year prospective study. SETTING: A population-based study in western Norway PARTICIPANTS: 178 community-dwelling subjects with Parkinson's disease. MEASUREMENTS: Main outcome measure was the time from baseline to nursing home admission. Baseline evaluation of motor symptoms (Unified Parkinson's Disease Rating Scale, UPDRS), cognition (clinical dementia interview, Gottfries, Brane & Steen dementia scale, and Mini-Mental State Examination), depression (clinical interview and the Montgomery & Asberg Depression Rating Scale), and psychotic symptoms (UPDRS Thought Disorder item) were performed. RESULTS: Forty-seven patients (26.4%) were admitted to a nursing home during the 4-year study period. Institutionalized patients were older, had more advanced Parkinson's disease with more severe motor symptoms and impairment of activities of daily living, were cognitively more impaired, were more often living alone, and had more hallucinations than those who continued to live at home. Duration of disease, levodopa dose, and gender distribution did not differ between the two groups. A Cox proportional hazards linear regression analysis showed that old age, functional impairment, dementia, and hallucinations were independent predictors of nursing home admission. CONCLUSIONS: Both motor and neuropsychiatric symptoms contributed to institutionalization, but the presence of hallucinations was the strongest predictor. This finding indicates it is possible that effective treatment of hallucinations may reduce the need for institutionalization in patients with Parkinson's disease.

Excessive daytime sleepiness and sleep benefit in Parkinson's disease: a community-based study.

The objective of this study was to investigate the frequency of excessive daytime sleepiness (EDS) and the beneficial effect of sleep on motor performance in an unselected community-based sample of patients with Parkinson's disease (PD). Furthermore, we wanted to identify possible risk factors to these phenomena. Detailed information on somnolence and sleep during daytime, as well as sleep benefit (SB) on awakening, was collected through a questionnaire among 245 patients with PD. Daytime somnolence was graded in groups of no somnolence, mild daytime sleepiness, and EDS. In addition, the occurrence of somnolence in the patients with PD was compared with the occurrence among control groups of patients with diabetes mellitus and of healthy elderly subjects. The correlations between EDS and SB and various motor- and non-motor symptoms of PD were evaluated. Among the patients with PD, 15.5% experienced EDS, significantly more than in the patients with diabetes mellitus (4%) and the healthy control subjects (1%). The frequency of mild daytime sleepiness was similar (10%) in patients with PD and control subjects. The patients with EDS had significantly higher staging of PD, were more disabled, and showed a higher frequency of cognitive decline compared with the patients without somnolence. They also had been using levodopa for a longer time and had more hallucinations. The occurrence of nocturnal sleeping problems and the use of sleeping pills was similar in the two groups, as was the mean age at examination, duration of PD, and presence of fluctuations and dyskinesias. SB was found in 42.2% of the patients with PD. These patients had been using levodopa for significantly longer and had significantly more fluctuations and dyskinesias compared with the patients without SB. Our results suggest that mild daytime sleepiness may be a result of normal aging, whereas more severe EDS can be explained by the neuropathologic changes of PD. The data from this community-based study confirms the previously reported high frequencies of SB.

Mental symptoms in Parkinson's disease are important contributors to caregiver distress.

OBJECTIVE: To determine the emotional and social distress of caring for a patient with Parkinson's disease and to explore the impact of motor and mental symptoms in subjects with Parkinson's disease on their caregivers' situation. DESIGN: Cross-sectional, population-based study using self-report questionnaires to measure caregiver distress and rating scales to assess patient symptomatology. SETTING: Neurology and old age psychiatry services in Stavanger, Norway. SUBJECTS: Caregivers of 94 home-dwelling patients with Parkinson's disease. Two control groups (patients with diabetes mellitus and healthy elderly). OUTCOME MEASURES: Measures of social and emotional distress in caregivers, including the Relative Stress Scale, Beck Depression Inventory and the General Health Questionnaire. RESULTS: Caregivers, in particular spouses, had more severe depression and a higher proportion reporting tiredness, sadness and less satisfaction with life compared with healthy elderly subjects. Using linear regression analysis, patient predictors of caregiver distress were depression, functional and cognitive impairment, agitation, aberrant motor behaviour and delusions. CONCLUSIONS: Caring for a spouse with Parkinson's disease is associated with emotional and social distress, underlining the importance of also assessing the needs of carers. Mental symptoms of parkinsonian patients were the most consistent and powerful predictors of caregiver distress, suggesting that identification and treatment of mental symptoms may reduce distress in caregivers of subjects with Parkinson's disease.

Range of neuropsychiatric disturbances in patients with Parkinson's disease.

OBJECTIVES: Disturbances of cognition and emotion are common in patients with Parkinson's disease. Most previous studies of psychopathology in Parkinson's disease have focused on a single psychiatric diagnosis or condition. The objective of this study was to describe the range of neuropsychiatric symptoms in a representative sample of patients with Parkinson's disease. METHODS: The sample of 139 patients was drawn from an epidemiological study of Parkinson's disease in Rogaland county, Norway, and represented 93% of those who had survived during the 4 years since the initial assessment. The diagnosis of Parkinson's disease was based on published criteria. Neuropsychiatric symptoms were assessed using the neuropsychiatric inventory, a caregiver based structured interview, which assesses severity and frequency of 10 psychiatric symptoms present during the past month. RESULTS: At least one psychiatric symptom was reported in 61% of the sample. The most common behaviours were depression (38%) and hallucinations (27%), and the least common symptoms were euphoria and disinhibition. The highest mean scores were found for depression, apathy, and hallucinations. Factor analysis showed that hallucinations, delusions, and irritability clustered into one factor, and apathy and anxiety constituted another factor. Psychiatric symptoms were more common among patients living in nursing homes compared with home dwelling patients, and correlated with stage of disease and cognitive impairment, but not with age or duration of disease. No relation to left or right sided parkinsonism was found. CONCLUSION: This study emphasises the importance of psychiatric symptoms in Parkinson's disease, which were present in most patients. Clinicians should focus on the emotional and cognitive disturbances in addition to the motor manifestations of the disease.

Olanzapine for psychosis in patients with Parkinson's disease with and without dementia.

Twenty-one patients with Parkinson's disease and psychosis were included in an open-label 8-week trial of olanzapine. Eight subjects had dementia. Six subjects (29%) discontinued treatment prematurely because of drowsiness. Delusions and hallucinations improved significantly, and 80% were rated as much or very much improved. There was no worsening of parkinsonism or cognition.

Influence of clinical and demographic variables on quality of life in patients with Parkinson's disease.

OBJECTIVES: To identify the clinical and demographic factors that are associated with a poor quality of life in patients with Parkinson's disease. METHODS: 233 of a total of 245 patients identified in a community based study in a Norwegian county participated in the study. Quality of life was measured by the Nottingham Health Profile (NHP). The results were compared with those in 100 healthy elderly people. Clinical and demographic variables were determined during a semistructured interview and by clinical examination by a neurologist. Multiple regression analyses were used to determine which variables were associated with higher distress scores. RESULTS: Patients with Parkinson's disease had higher distress scores than the healthy elderly people for all the NHP dimensions. The variables that most strongly predicted a high total NHP score were depressive symptoms, self reported insomnia, and a low degree of independence, measured by the Schwab and England scale. Severity of parkinsonism contributed, but to a lesser extent. Nearly half the patients with Parkinson's disease reported lack of energy, compared with a fifth of the control group. Severity of depressive symptoms and a higher score on the UPDRS motor subscale only partly accounted for this finding. Only 30% of the variation in NHP energy score was explained by the predictive variables identified in this study. CONCLUSIONS: Parkinson's disease has a substantial impact on health related quality of life. Depressive symptoms and sleep disorders correlated strongly with high distress scores. Patients with Parkinson's disease should be examined for both conditions, which require treatment. Low energy was commonly reported and may be a separate entity of Parkinson's disease.

Fatigue in patients with Parkinson's disease.

OBJECTIVE: To compare the prevalence of fatigue in patients with Parkinson's disease (PD) with that in healthy elderly people and to explore the suggestion that fatigue is an independent symptom of PD. DESIGN: Questionnaire survey. SETTING: Community-based population. PATIENTS AND CONTROL SUBJECTS: 233 patients derived from a prevalence study in the county of Rogaland, Norway and 100 healthy elderly people with the same age and sex distribution as the patients with PD. MAIN OUTCOME MEASURE: A score for fatigue was obtained by combining the results from the rating scale for low energy in the Nottingham Health Profile (NHP) with the results obtained from a 7-point scale devised to evaluate fatigue. RESULTS: 44.2% of the patients with PD and 18% of the healthy elderly control subjects reported fatigue. Fatigue was associated with depression, dementia, disease severity, disease duration, levodopa dose, and the use of sleeping pills. In a multivariate analysis, only depressive symptoms reached statistical significance. The prevalence of fatigue in patients with PD who were not depressed, demented, or had a sleeping disturbance was similar to that found in the total PD population. CONCLUSION: Fatigue is a common symptom in PD. Although fatigue correlated with depressive symptoms, patients with PD who did not have depression, dementia, or sleep disturbances also reported a high prevalence of this symptom. This supports the hypothesis that fatigue is an independent symptom of PD overlapping with, but not causally related to, the concurrence of depressive symptoms.

A community-based study of sleep disorders in patients with Parkinson's disease.

Sleep disorders are common and well documented in patients with Parkinson's disease (PD). However, most data on sleep in patients with PD are derived from selected patient populations. This community-based survey evaluated the prevalence of and risk factors for sleep disturbances in an unselected group of 245 patients with PD and two control groups of similar age and sex distribution: 100 patients with another chronic disease (diabetes mellitus) and 100 healthy elderly persons. Nearly two thirds of the patients with PD reported sleep disorders, significantly more than among patients with diabetes (46%) and healthy control subjects (33%). About a third of the patients with PD rated their overall nighttime problem as moderate to severe. The most common sleep disorders reported by the patients with PD were frequent awakening (sleep fragmentation) and early awakening. Sleep initiation showed no significant difference compared with the control groups. Pain and cramps were not more prevalent among the patients with PD, but they were more likely to report sleep disturbed by myoclonic jerks. Use of sedatives was common in all three groups but significantly higher in the PD group than in the healthy elderly. Symptoms of depression and duration of levodopa treatment showed a significant correlation with sleep disorders in the PD group. This community-based study confirms that sleep disorders are common and distressing in patients with PD. The strong correlation between depression and sleep disorders in patients with PD underlines the importance of identifying and treating both conditions in these patients.

Quality of life measurements in patients with Parkinson's disease: A community-based study.

The objective of this paper is to evaluate the health-related quality of life in a community-based population of patients with Parkinson's disease (PD). The PD population consisted of 233 patients and was derived from a wider prevalence study in the county of Rogaland, Norway. The quality of life was measured by the Nottingham Health Profile (NHP) and four general health and well-being questions. The results were compared with quality of life measurements in 100 patients with diabetes mellitus (DM) and 100 healthy elderly people. The control groups had the same age and sex distribution as the patients with PD. This study showed that PD has a substantial impact on the health-related quality of life. Patients with PD had higher distress scores in all measured dimensions of the NHP than the two control groups. The negative impact of PD was highest for physical mobility, emotional reactions, social isolation and energy. Correlation analysis of the quality of life showed that age, duration of levodopa therapy, higher levodopa doses, depression, cognitive impairment and more advanced disease correlated with higher distress scores in patients with PD. The results of this study showed that PD had a broad impact on well-being, more so than DM. The distress related to the severity of the disease, as well as to depressive symptoms and cognitive impairment. An important finding was the underestimated distress related to lack of energy. Copyright 1998 Lippincott Williams & Wilkins

Risk factors for depression in Parkinson disease.

OBJECTIVE: To evaluate whether depression in Parkinson disease (PD) is more closely related to the underlying neuropathological process or to environmental and psychological factors by correlating depression in PD with various clinical and demographic variables. DESIGN: Major depression, level of depressive symptoms as measured with the Montgomery-Aasberg Depression Rating Scale (MADRS), and clinical characteristics were investigated in a community-based cross-sectional study of carefully diagnosed patients with PD. Both bivariate and multivariate correlation analyses were performed to investigate correlations and predictive values of possible risk factors for major depression and MADRS score in PD. SETTING: Depression among patients with PD derived from a prevalence study in the county of Rogaland, Norway. PATIENTS: Two hundred forty-five patients with PD. RESULTS: Impaired cognitive function and the presence of a thought disorder were significant predictors of major depression. A Mini-Mental State Examination sum score below 24 and level 2 or higher on the thought disorder subscale of the Unified Parkinson Disease Rating Scale increased the probability of major depression by a factor of 6.6 and 3.5, respectively. Higher MADRS scores were also associated with lower Mini-Mental State Examination score and higher thought disorder score. In addition, MADRS scores also correlated with more impairment in activities of daily living, presence of motor fluctuations, more evidence of atypical parkinsonism, higher daily doses of levodopa, and younger age on the day on which prevalence was determined. CONCLUSIONS: Most of the observations of this study favor the hypothesis that depression in PD is a primary consequence of brain dysfunction. Situational factors may, however, also contribute to mood changes in PD.

Patient characteristics, MRI examination, and dopaminergic drug response in clinical possible Parkinson's disease.

Patients with parkinsonism can be classified as clinical definite, probable, possible, or unlikely Parkinson's disease (PD). Possible PD includes patients with PD according to conventional diagnostic criteria and with at least a moderate response to dopamine agonists. However, these patients have clinical features that may reduce the probability for idiopathic PD. The objective of this study was to clinically characterize patients with possible disease in a prevalence study of PD and to indicate the frequency of idiopathic PD in this group of patients. The diagnostic re-evaluation was based on detailed MRI examinations and investigations of dopaminergic drug response after several years of treatment. In a community-based prevalence study in Norway, comprising 245 PD patients, we found 36 patients (15%) with clinical possible PD. The patients with possible disease had significant and clinically important differences in demographic and disease characteristics compared to patients with definite and probable PD. Possible PD patients were older at disease onset, more disabled, and had more neurobehavioral disorders. MRI examinations of 14 of the 36 patients with possible PD in the prevalence study revealed significant group effects compared to an age-matched control group, with reduced pars compacta width and increased cortical atrophy. In individual patients, signal attenuation consistent with vascular lesions of the basal ganglia contributed to diagnostic reclassification. Dopaminergic drug withdrawal revealed no response in 4 of 12 examined patients. Two of the remaining eight patients had a clear short-duration drug response. Six patients had only a varying degree of long-duration response. The re-evaluation of diagnosis indicates that probably less than half of the patients with clinical possible PD have idiopathic disease. Patients with atypical features and diagnosed as possible PD should thus be excluded from studies with a presumed high specificity for idiopathic PD.

Frequency of dementia in Parkinson disease.

OBJECTIVE: To investigate the frequency of dementia in patients with Parkinson disease (PD). DESIGN: Community-based prevalence study. SETTING: The study population comprised 220,858 inhabitants from the Rogaland County, Norway. PARTICIPANTS: Almost 400 participants were examined by a neurologist, and 245 were given the diagnosis of PD and included in the study. MEASUREMENTS: Mental functioning was rated with the Mini-Mental State Examination; Gottfries, Bråne, and Steen scale; and the intellectual subscale of the Unified Parkinson's Disease Rating Scale. Criteria from the Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised, were applied during a semistructured interview to determine the diagnosis of dementia. RESULTS: Dementia was found in 67 patients (27.7%). Patients with dementia were older at the time of the study and at onset of PD and had had PD longer than the patients without dementia. Major depression was more common among patients with dementia (23%) than among patients without dementia (2.3%) (chi 2 , P < .001), and patients with dementia were more often institutionalized than those without dementia (62% vs 6%, respectively, chi 2 , P < .001). Atypical neurologic features for idiopathic PD (ie, early occurrence of autonomic failure, symmetrical disease presentation, and only moderate response to a dopamine agonist) were associated with more severe dementia of a higher frequency rate and with lower scores on cognitive rating scales. CONCLUSION: Approximately one quarter of the patients with PD had dementia with the motor manifestations of PD. Dementia was associated with depression, institutionalization, older age at onset of PD, and atypical neurologic features.

The occurrence of depression in Parkinson's disease. A community-based study.

OBJECTIVE: To investigate the frequency of major depression (MD) and the severity of depressive symptoms among patients with Parkinson's disease (PD). DESIGN: The PD population was derived from a community-based prevalence study. Total case ascertainment and a high diagnostic accuracy of PD were attempted through a detailed community study and the use of a new clinical diagnostic classification. Major depression was diagnosed according to the criteria in the Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition. The severity of depression in the prevalence population was scored with the Montgomery and Asberg Depression Rating Scale. The occurrence of depressive symptoms among patients with PD was compared with the occurrence among age-matched groups of patients with diabetes mellitus and of healthy elderly. In addition, the patients with PD and the control groups completed the Beck Depression Inventory. SETTING: Depression among patients with PD derived from a prevalence study in the county of Rogaland, Norway. PATIENTS: Two hundred forty-five patients with PD. Two age-matched control groups (each including 100 patients); one group included patients with diabetes mellitus and the other, healthy elderly. RESULTS: Of the 245 patients with PD, 7.7% met the criteria for MD. Based on their Montgomery and Asberg Depression Rating score, 5.1% of the patients were moderately to severely depressed whereas another 45.5% had mild depressive symptoms. Among the patients who scored 20 or more on the Mini-Mental State Examination, 3.6% had MD compared with 25.6% of the patients with a score below 20. The frequency of patients with a Beck Depression Inventory score of 18 or more was higher in the PD group (24.1%) than among patients with diabetes mellitus (11%) and the healthy elderly controls (4%). CONCLUSION: This study suggests that the prevalence of MD in PD is lower than previously assumed, but a substantial proportion of patients with PD have less severe depressive symptoms.

The epidemiology of Parkinson's disease in the county of Rogaland, Norway.

The objective of this investigation was to clarify the epidemiology of idiopathic Parkinson's disease (PD) in the county of Rogaland, Norway. Total case ascertainment and a high diagnostic accuracy were attempted through a detailed community study and the use of a new clinical diagnostic classification. The study population comprised 220,858 inhabitants, and a total of nearly 400 patients was interviewed and examined by a neurologist. On prevalence day, January 1, 1993, 245 patients were included in the study. The diagnostic classification revealed 135 patients with clinically definite, 74 with probable, and 36 with possible PD. The crude prevalence rate was shown to be 110.9 per 100,000 inhabitants. The total age-adjusted prevalence was calculated to be 102.4 per 100,000 and to 120.9 per 100,000 men and 89.8 per 100,000 women. Among the 245 patients, 28 patients had a tremor-dominant disease, 50 patients an akinetic-dominant disease, and 167 patients a mixed clinical pattern of PD. Age-adjusted prevalence figures were slightly higher for rural compared to urban areas. About 50% of the PD patients were in need of public help, 15% had complaints about pain related to their parkinsonism, and after approximately 6 years of levodopa treatment, 20% were suffering from clinical fluctuations. The study showed that 40% of the patients had some degree of thought disorder. The prevalence figures for PD in this study are slightly lower than those reported from most previous prevalence studies with a comparable study design for case finding. This may be due to a careful diagnostic evaluation with the use of specified diagnostic criteria, excluding patients with other parkinsonian syndromes.

Clinical diagnosis of Parkinson's disease. Proposal of diagnostic subgroups classified at different levels of confidence.

The objective of this paper is to evaluate the accuracy of conventional diagnostic criteria for Parkinson's disease and give an overview of alternative causes to parkinsonian syndromes. We also propose a new approach to the clinical diagnosis of Parkinson's disease, which may improve the diagnostic accuracy. The available information on autopsy findings in patients clinically diagnosed as Parkinson's disease shows that 20 to 30% of these patients do not have the typical neuropathological features with Lewy bodies and cell loss in the substantia nigra. The use of selected additional clinical criteria improves the diagnostic accuracy, however, at the cost of rejecting a rather large group of patients with idiopathic disease verified by autopsy. Based on this fact and a review of the literature on parkinsonian syndromes that may be confused with idiopathic Parkinson's disease, we propose criteria for diagnostic subgroups of the disease classified at different levels of confidence. The suggested diagnostic subgroups are clinical definite, probable and possible Parkinson's disease with a decreasing level of specificity and an increasing level of sensitivity in the different patient categories. The clinical features given special importance in this classification includes presence of resting tremor, asymmetrical disease, response to dopamine agonism and presence of atypical clinical features like dementia and clinical autonomic failure at onset and pyramidal or cerebellar signs at examination. In addition, a history indicating possible etiology for another parkinsonian syndrome will exclude the diagnosis.

[Electroconvulsive treatment in parkinsonism]. / Elektrokonvulsiv behandling ved parkinsonisme.

This article describes three patients with different causes of parkinsonian syndromes where electroconvulsive treatment markedly improved their symptoms. The results are discussed and compared with those of previously published studies. Most of these studies, however, have substantial methodological shortcomings. The mechanism inducing the improvement is unknown, but could possibly be increased postsynaptic dopamine function. The literature indicates that electroconvulsive treatment has antiparkinsonian effects independent of any effect on mental state. We suggest that patients with parkinsonian syndromes, who respond unsatisfactorily to conventional therapy, as well as patients who develop severe neuropsychiatric manifestations, should be considered for a course of electroconvulsive treatment.