Suicide in patients with Parkinson's disease. An epidemiological study

Association between new-onset Parkinson's disease and suicide risk in South Korea: a nationwide cohort study

BACKGROUND

Parkinson's disease (PD) is an increasingly common neurodegenerative disease in an aging society. Whether PD is associated with an increased suicide risk is unclear. Thus, we investigated the effect of new-onset PD on suicide.

METHODS

Using the National Health Insurance Service Senior Sample Cohort of South Korea, 17,143 incident PD patients and 17,143 risk set controls, matched by propensity score, were selected for follow-up. The incidence rate of suicide and 95% confidence interval (CI) were calculated based on a generalized linear model of the Poisson distribution. Effect sizes were expressed as hazard ratios (HRs) using the Cox proportional hazards model with a robust variance estimator that incorporated clustering within matched pairs.

RESULTS

The incidence rate of suicide was 206.7 cases per 100,000 person-years (95% CI, 172.8-246.9) among the PD cohort. Compared to the matched controls, patients with PD were 2.64 times (HR, 2.64; 95% CI, 1.31-5.30) more likely to commit suicide during the first 180 days of follow-up and 2.47 times (HR, 2.47; 95% CI, 1.42-4.28) within the first 365 days of follow-up. During the entire follow-up period, patients with PD were 2.26 times more likely to commit suicide than were their matched controls (HR, 2.26; 95% CI, 1.67-3.06).

CONCLUSION

Our findings indicated an increased risk of suicide in patients with new-onset PD, regardless of the period after diagnosis. Incorporating mental health care with social and environmental interventions into primary care and PD-specialized care can help reduce suicide risk in people with PD, improving suicide prevention, identification, and risk assessment.

Management of psychiatric disorders in Parkinson's disease : Neurotherapeutics - Movement Disorders Therapeutics

Affective disorders (depression and anxiety), psychosis, impulse control disorders, and apathy are common and sometimes disabling psychiatric conditions in Parkinson disease (PD). Psychiatric aspects of PD are associated with numerous adverse outcomes, yet in spite of this and their high frequency, there remains incomplete understanding of epidemiology, presentation, risk factors, neural substrate, and management strategies. Psychiatric features are typically co- or multimorbid, and there is great intra- and interindividual variability in presentation [1]. The neuropathophysiological changes that occur in PD, as well as the association between PD treatment and particular psychiatric disorders, suggest a neurobiological contribution to many psychiatric symptoms. There is evidence that psychiatric disorders in PD are still under-recognized and undertreated, and although psychotropic medication use is common, randomized controlled trials demonstrating efficacy and tolerability are largely lacking. Future research on neuropsychiatric complications in PD should be oriented toward determining modifiable correlates or risk factors, and most importantly, establishing efficacious and well-tolerated treatment strategies.

Parkinson's Disease-Related Risk of Suicide and Effect of Deep Brain Stimulation: Meta-Analysis

Background

Previous studies investigated the risk of suicide in patients with Parkinson's disease (PD) but reported discrepant results. Deep brain stimulation (DBS) is an effective therapy for PD, while its effect on suicide risk has seldom been researched. This meta-analysis aimed to estimate the risk of suicide and/or suicidal ideation in PD patients and in PD patients who underwent DBS.

Methods

Relevant articles published in the PubMed or EMBASE or CNKI database from 1990 to December 2019 were sourced, and the combined standardized mortality rate (SMR) or odds ratio (OR) was pooled.

Result

A total of 1070 articles were found. After screening, 4 cross-sectional studies, 4 cohort studies, 2 randomized controlled trial studies, and 2 case-control studies were included in this meta-analysis. Pooled data indicated that PD patients may have increased risk of suicide (lnSMR, 0.459; 95% confidence interval (CI), 0.286 to 0.632; p < 0.001). No significant difference was found in the risk of suicide when comparing PD patients who underwent DBS with PD patients who received only drug therapy (OR = 2.844, 95%CI: 0.619 to 13.072, p=0.179). DBS may increase the risk of suicide and/or suicidal ideation in PD patients compared with general population (lnSMR = 3.383, 95%CI: 2.839 to 3.927, p < 0.001).

Conclusion

PD patients have higher risk of suicide and/or suicidal ideation compared with controls, while PD patients who received DBS tend to have an increased risk of suicide or suicidal ideation. Psychological evaluation is needed in PD patients, and pre- and post-operation evaluations are necessary for PD patients who underwent DBS.

Suicide in Parkinson's Disease: A Systematic Review

Psychiatric disorders and suicide have been reported in patients suffering from Parkinson's disease. The aims of the present paper were to determine whether patients with Parkinson's disease have an increased rate of suicide and to identify the clinical features possibly associated with suicide risk in Parkinson's disease. We also reviewed the studies on suicide risk in Parkinson's disease in patients after deep brain stimulation. We performed a Medline, Excerpta Medica, PsycLit, PsycInfo and Index Medicus search to identify all articles published on this topic from 1970 to 2019. The following search terms were used: suicide OR suicide attempt OR suicidal ideation OR suicide risk AND Parkinson's disease AND Parkinson's disease and deep brain stimulation. The studies we identified that assessed the suicide rate associated with Parkinson's disease yielded contrasting results, although an increase in suicidal ideation did emerge. The studies on the effect of deep brain stimulation on suicide risk in Parkinson's disease also reported mixed findings. Psychiatric symptoms, including depression, appear to be associated with suicide risk in patients with Parkinson's disease undergoing medical and after surgical treatment. The studies reviewed suggest that suicidal ideation is increased in Parkinson's disease. Further longitudinal studies designed to assess suicidality in this condition are still needed.

The Neuropsychiatry of Parkinson Disease: A Perfect Storm

Affective disorders, cognitive decline, and psychosis have long been recognized as common in Parkinson disease (PD), and other psychiatric disorders include impulse control disorders, anxiety symptoms, disorders of sleep and wakefulness, and apathy. Psychiatric aspects of PD are associated with numerous adverse outcomes, yet in spite of this and their frequent occurrence, there is incomplete understanding of epidemiology, presentation, risk factors, neural substrate, and management strategies. Psychiatric features are typically multimorbid, and there is great intra- and interindividual variability in presentation. The hallmark neuropathophysiological changes that occur in PD, plus the association between exposure to dopaminergic medications and certain psychiatric disorders, suggest a neurobiological basis for many psychiatric symptoms, although psychological factors are involved as well. There is evidence that psychiatric disorders in PD are still under-recognized and undertreated and although psychotropic medication use is common, controlled studies demonstrating efficacy and tolerability are largely lacking. Future research on neuropsychiatric complications in PD should be oriented toward determining modifiable correlates or risk factors and establishing efficacious and well-tolerated treatment strategies.

Suicide in Parkinson's disease

Persons with Parkinson's disease (PwP) have many known risk factors for suicide and suicidal ideation (SI). Despite this, there is limited understanding of suicidality in this population. We conducted a systematic review to synthesise the available literature on suicidality in PwP and highlight areas for potential intervention and further research. We identified 116 articles discussing SI, suicidal behaviours, suicide attempts and/or fatal suicide in PwP. These articles describe prevalence, suicide methods, risk factors for suicide and SI and treatment of suicidality. In this review, we summarise the current literature and provide suggestions for how clinicians can identify and treat PwP who are at risk for suicide, for example, through aggressive treatment of depression and improved screening for access to lethal means.

Suicidal ideation, perceived disability, hopelessness and affective temperaments in patients affected by Parkinson's disease

BACKGROUND

Previous studies investigating the risk of suicide in patients with Parkinson's disease (PD) have reported conflicting results. This study evaluated suicide risk in PD and investigated the relationship between suicide risk and perceived disability, hopelessness and affective temperaments in PD.

METHODS

One-hundred and twenty PD patients were consecutively enrolled. The diagnosis of PD was based on clinical criteria. All patients underwent a psychiatric evaluation that included the administration of the Columbia-Suicide Severity Rating Scale, the Italian Perceived Disability Scale, the Beck Hopelessness Inventory and the TEMPS-A questionnaire. The results were compared with those of a control group of 91 patients affected by another chronic disease, ie, open angle glaucoma.

RESULTS

Parkinson's disease patients had higher suicidal ideation, higher perceived disability and lower hyperthymia than the control group. In PD, higher perceived disability was associated with higher current and lifetime suicidal ideation, lower hyperthymia, older age and higher scores on negative temperaments. Suicidal ideation, negative temperaments and hopelessness were risk factors for perceived disability, while hyperthymia was a protective factor for perceived disability.

DISCUSSION

Patients with PD have an increased risk of suicidal ideation. Increased suicidal ideation in PD is associated with the increased perceived disability. A psychiatric assessment that includes the investigation of suicide risk and perceived disability is recommended in patients with PD.

Perceived Treatment Status of Fluctuations in Parkinson Disease Impacts Suicidality

OBJECTIVE

On/off motor fluctuations in Parkinson disease (PD) can be associated with extreme mood fluctuations and severe dysphoria. The impact of these affective symptoms may be overlooked in the treatment of motor fluctuations. Our goal was to examine the relationship between motor fluctuations, their treatment status, and suicidality in PD participants.

METHODS

We analyzed data from the Methods of Optimal Depression Detection in Parkinson's Disease (MOOD-PD) study of 223 individuals with PD. Suicidality was measured using items from four depression scales: Hamilton Depression Rating Scale (HAM-D-17); Montgomery-Åsberg Depression Rating Scale (MADRS); Inventory for Depressive Symptomatology (IDS-C); and the self-rated Beck Depression Inventory (BDI). Multivariable Poisson regression analyses tested whether self-reported motor fluctuations and their treatment status were associated with suicidality while controlling for recognized risk factors.

RESULTS

Thirty-seven participants (16.6%) self-reported suicidality and 89 (39.5%) self-reported motor fluctuations, of whom 21 (23.6%) perceived their fluctuations as untreated. Participants reporting untreated motor fluctuations more frequently had a current depressive disorder (p < 0.001) and endorsed suicidality (p = 0.006) than participants with treated or no fluctuations. They also had significantly higher total scores on the HAM-D-17, MADRS, IDS-C, and BDI depression scales (p < 0.001 for each). Regression analyses showed significant associations between untreated motor fluctuations and higher scores on suicide questions extracted from the HAM-D-17, MADRS, and IDS-C (p < 0.01 for each).

CONCLUSIONS

PD patients with untreated motor fluctuations are at increased risk for suicidal thoughts and should be monitored for mood changes as treatment is adapted.

Suicide in Parkinson's Disease

BACKGROUND

Suicide is a potentially preventable event. Suicidal ideation is common in Parkinson's disease (PD), but literature on completed suicides is scarce. In this case-control study, we compared the clinical characteristics of PD subjects who completed suicide (case) with those who died from natural causes (control).

METHODS

PD patients from the National Neurosciences Institute's movement disorders database from 2002 till 2012 were identified. The database was linked to the Singapore National Registry of Disease Office for mortality information, and suicide deaths were confirmed with the coroner's office. The demographic and clinical variables were compared between the cases and controls and the significant factors were further analyzed using logistic regression analysis.

RESULTS

During the study period, 366 deaths were recorded and suicide accounted for 11 deaths. Ten subjects with suicide deaths with complete clinical information were compared with randomly selected 30 PD subjects who had died from natural causes. PD suicide patients were younger (65.9 vs. 74.48 years), had less comorbidities (CWI: 2.6 vs. 4.63), better cognition (MMSE: 25.75 vs. 21.36), lower 'ON' UPDRS motor scores (20.83 vs. 41.63), lower H &Y stage (2.16 vs. 3.86), and higher use of Entacapone than the PD non-suicide group.

CONCLUSION

Suicide is potentially preventable tragedy. PD patients with the identified clinical characteristics should be closely monitored for suicide ideations. Motor fluctuation is a treatable factor in such patients and should be aggressively managed.

Hospital care for mental health and substance abuse conditions in Parkinson's disease

OBJECTIVE

The objective of this study was to examine mental health conditions among hospitalized individuals with Parkinson's disease in the United States.

METHODS

This was a serial cross-sectional study of hospitalizations of individuals aged ≥60 identified in the Nationwide Inpatient Sample dataset from 2000 to 2010. We identified all hospitalizations with a diagnosis of PD, alcohol abuse, anxiety, bipolar disorder, depression, impulse control disorders, mania, psychosis, substance abuse, and attempted suicide/suicidal ideation. National estimates of each mental health condition were compared between hospitalized individuals with and without PD. Hierarchical logistic regression models determined which inpatient mental health diagnoses were associated with PD, adjusting for demographic, payer, geographic, and hospital characteristics.

RESULTS

We identified 3,918,703 mental health and substance abuse hospitalizations. Of these, 2.8% (n = 104, 437) involved a person also diagnosed with PD. The majority of mental health and substance abuse patients were white (86.9% of PD vs 83.3% of non-PD). Women were more common than men in both groups (male:female prevalence ratio, PD: 0.78, 0.78-0.79, non-PD: 0.58, 0.57-0.58). Depression (adjusted odds ratio 1.32, 1.31-1.34), psychosis (adjusted odds ratio 1.25, 1.15-1.33), bipolar disorder (adjusted odds ratio 2.74, 2.69-2.79), impulse control disorders (adjusted odds ratio 1.51, 1.31-1.75), and mania (adjusted odds ratio 1.43, 1.18-1.74) were more likely among PD patients, alcohol abuse was less likely (adjusted odds ratio 0.26, 0.25-0.27). We found no PD-associated difference in suicide-related care.

CONCLUSIONS

PD patients have unique patterns of acute care for mental health and substance abuse. Research is needed to guide PD treatment in individuals with pre-existing psychiatric illnesses, determine cross provider reliability of psychiatric diagnoses in PD patients, and inform efforts to improve psychiatric outcomes. © 2016 International Parkinson and Movement Disorder Society.

Physical diseases as predictors of suicide in older adults: a nationwide, register-based cohort study

PURPOSE

The objective of the study was to examine the association between 39 physical diseases and death by suicide in older adults.

METHODS

Individual-level register data on all older adults aged 65 years and over living in Denmark during 1990-2009 (N = 1,849,110) were analysed. Rate ratios were calculated for 39 physical diseases while adjusting for period, age group, conjugal status, income, physical comorbidity, and psychiatric disorders.

RESULTS

In all, 4792 older adults aged 65+ died by suicide during the follow-up of >16 million person-years. Gastrointestinal cancer was linked to a rate ratio of 2.5 (95 % CI 1.9-3.5) in men while excess suicide risk for women with brain cancer was 3.5 (95 % CI 1.1-10.8) within three years of diagnosis. Men and women diagnosed with liver diseases within three years experienced a 2.7- (95 % CI 1.7-4.2) and 4.0- (95 % CI 2.5-6.4) fold higher risk of suicide, respectively, than those not diagnosed. Elevated risks of suicide were identified for lung cancer, gastrointestinal cancer, breast cancer, genital cancer, bladder cancer, lymph node cancer, epilepsy, cerebrovascular diseases, cataract, heart diseases, chronic obstructive pulmonary disorders (COPD), gastrointestinal disease, liver disease, arthritis, osteoporosis, prostate disorders, male genital disorders, and spinal fracture when compared to persons not diagnosed within three years.

CONCLUSIONS

Multiple physical diseases were linked to increased risks of suicide in older adults. Increased attention to suicidal ideation and risk assessment might be warranted during the diagnosis and treatment of these disorders.

Suicidal behavior among Turkish patients with Parkinson's disease

OBJECTIVE

To investigate the predictors of suicidal ideation and attempts among Turkish Parkinson's disease (PD) patients.

MATERIALS AND METHODS

The study comprised 120 patients with PD. Clinical findings were obtained by using the Unified Parkinson's Disease Rating Scale. Disease severity was measured by the Hoehn and Yahr staging scale, and the Schwab and England Activities of Daily Living scale was used for patient disability. Psychiatric evaluation was performed by the same psychiatrist using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) Axis I Disorders. Severity of depression was measured with the Hamilton Depression Rating Scale. Suicidal ideation and attempts were considered positive if experienced during the patient's lifetime. The Suicide Probability Scale was used to assess the risk of suicide. Data were analyzed by logistic regression models to identify variables associated with suicidal ideation and attempts.

RESULTS

Based on logistic regression analysis, education level, age of disease onset, disease duration, depression, and history of impulse-control disorder (ICD) behaviors were significant predictors of suicidal ideation. The risk rate in the presence of depression and history of ICD behaviors was increased by 5.92 and 4.97, respectively. Additionally, lifetime prevalence of suicidal ideation was found in 11.6% (14 of 120) of PD patients, although no patient had ever attempted suicide.

CONCLUSION

Turkish patients with PD who exhibit a high risk for suicidal ideation also experience disease starting at an earlier age, longer disease duration, presence of depression, and ICD behaviors, and should be monitored carefully.

Suicide ideation and behaviours after STN and GPi DBS surgery for Parkinson's disease: results from a randomised, controlled trial

BACKGROUND

The risk of suicide behaviours post-deep brain stimulation (DBS) surgery in Parkinson's disease (PD) remains controversial. We assessed if suicide ideation and behaviours are more common in PD patients (1) randomised to DBS surgery versus best medical therapy (BMT); and (2) randomised to subthalamic nucleus (STN) versus globus pallidus interna (GPi) DBS surgery.

METHODS

In Phase 1 of the Veterans Affairs CSP 468 study, 255 PD patients were randomised to DBS surgery (n=121) or 6 months of BMT (n=134). For Phase 2, a total of 299 patients were randomised to STN (n=147) or GPi (n=152) DBS surgery. Patients were assessed serially with the Unified Parkinson's Disease Rating Scale Part I depression item, which queries for suicide ideation; additionally, both suicide behaviour adverse event data and proxy symptoms of increased suicide risk from the Parkinson's Disease Questionnaire (PDQ-39) and the Short Form Health Survey (SF-36) were collected.

RESULTS

In Phase 1, no suicide behaviours were reported, and new-onset suicide ideation was rare (1.9% for DBS vs 0.9% for BMT; Fisher's exact p=0.61). Proxy symptoms of relevance to suicide ideation were similar in the two groups. Rates of suicide ideation at 6 months were similar for patients randomised to STN versus GPi DBS (1.5% vs 0.7%; Fisher's exact p=0.61), but several proxy symptoms were worse in the STN group.

CONCLUSIONS

Results from the randomised, controlled phase of a DBS surgery study in PD patients do not support a direct association between DBS surgery and an increased risk for suicide ideation and behaviours.

Is depression in Parkinson's disease (PD) a specific entity?

BACKGROUND

Clinical lore and research have suggested for a long time that depression and PD are closely related. We examined the validity of depression associated with PD (dPD) as a specific subtype of depression according to face validity, descriptive validity, construct validity and predictive validity.

METHODS

The English literature was reviewed after searching the MEDLINE database up to June 2010.

RESULTS

There appears to be three possible subtypes of comorbid depression: 1) patients who would have been depressed even if they had no PD (nonspecific-casual comorbid dPD), 2) patients who would have been depressed if they had had another disabling medical illness (nonspecific-reactive comorbid dPD) 3) those for which depression is directly related to the underlying pathophysiology of PD (specific comorbid dPD). These latter patients may more often present with particular clinical characteristics (descriptive validity): absence of history of depression or only within 5 years prior to onset of PD, absence of guilty thoughts and self-blame, absence of suicidal behavior, right-sided onset. However, dPD is only partly responsive to dopamine replacement and cannot be solely explained by dopamine deficiency. Other neurotransmitter systems are affected in PD and are involved in the pathophysiology of dPD. Their relative involvement however may differ from that in idiopathic depression (i.e.: lesser involvement of serotonergic systems).

LIMITATIONS

Therapeutic data are limited to few controlled trials.

CONCLUSIONS

Further research may allow differential diagnosis between dPD subtypes (i.e.: those who do and do not result from the underlying pathophysiological process of PD) and help inform treatment choice.

The temptation of suicide: striatal gray matter, discounting of delayed rewards, and suicide attempts in late-life depression

BACKGROUND

Converging evidence implicates basal ganglia alterations in impulsivity and suicidal behavior. For example, D2/D3 agonists and subthalamic nucleus stimulation in Parkinson's disease (PD) trigger impulse control disorders and possibly suicidal behavior. Furthermore, suicidal behavior has been associated with structural basal ganglia abnormalities. Finally, low-lethality, unplanned suicide attempts are associated with increased discounting of delayed rewards, a behavior dependent upon the striatum. Thus, we tested whether, in late-life depression, changes in the basal ganglia were associated with suicide attempts and with increased delay discounting.

METHOD

Fifty-two persons aged ≥ 60 years underwent extensive clinical and cognitive characterization: 33 with major depression [13 suicide attempters (SA), 20 non-suicidal depressed elderly] and 19 non-depressed controls. Participants had high-resolution T1-weighted magnetization prepared rapid acquisition gradient-echo (MPRAGE) magnetic resonance imaging (MRI) scans. Basal ganglia gray matter voxel counts were estimated using atlas-based segmentation, with a highly deformable automated algorithm. Discounting of delayed rewards was assessed using the Monetary Choice Questionnaire (MCQ) and delay aversion with the Cambridge Gamble Task (CGT).

RESULTS

SA had lower putamen but not caudate or pallidum gray matter voxel counts, compared to the control groups. This difference persisted after accounting for substance use disorders and possible brain injury from suicide attempts. SA with lower putamen gray matter voxel counts displayed higher delay discounting but not delay aversion. Secondary analyses revealed that SA had lower voxel counts in associative and ventral but not sensorimotor striatum.

CONCLUSIONS

Our findings, although limited by small sample size and the case-control design, suggest that striatal lesions could contribute to suicidal behavior by increasing impulsivity.

Parkinson's disease: the quintessential neuropsychiatric disorder

Although diagnosed by characteristic motor features, Parkinson's disease may be preceded, and is frequently accompanied by, a wide range of cognitive and neuropsychiatric features. In addition to the most commonly studied disorders of dementia, depression, and psychosis, other relatively common and clinically significant psychiatric complications include impulse control disorders, anxiety symptoms, disorders of sleep and wakefulness, and apathy. These problems may be underrecognized and are frequently undertreated. The emergent focus on nonmotor aspects of Parkinson's disease over the past quarter of a century is highlighted by a nonlinear increase in the number of articles published devoted to this topic. Although the development of newer antidepressants, atypical antipsychotics, and cholinesterase inhibitors in recent years has had a positive benefit on the management of these troublesome and distressing symptoms, responses are frequently suboptimal, and this remains an area of major unmet therapeutic need.

Suicide and suicidal ideation in Parkinson's disease

Little is known about the prevalence and correlates of suicidal behavior in Parkinson's disease (PD). In the first part of the study, we followed a cohort of 102 consecutive PD patients for 8 years and found that the suicide-specific mortality was 5.3 (95% CI 2.1-12.7) times higher than expected. In the second part, we tested 128 PD patients for death and suicidal ideation and administered an extensive neurological, neuropsychological and psychiatric battery. Current death and/or suicidal ideation was registered in 22.7%. On univariate logistic regression analysis, psychiatric symptoms (depression, but also anxiety and hopelessness), but not the PD-related variables, were associated with such ideation. On multivariate logistic regression analysis this association held for major depression (odds ratio=4.6; 95% CI 2.2-9.4; p<0.001), psychosis (odds ratio=19.2; 95% CI 1.4-27.3; p=0.026), and increasing score of the Beck Hopelessness Scale (odds ratio=1.2; 95% CI 1.0-1.4; p=0.008). In conclusion, the suicide risk in PD may not be as high as it is expected, but it is certainly not trivial. According to our data almost a quarter of PD patients had death and/or suicidal ideation, that may significantly influence their quality of life.

Parkinson's disease and suicide: a profile of suicide victims with Parkinson's disease in a population-based study during the years 1988-2002 in Northern Finland

OBJECTIVE

We studied the prevalence of hospital-treated Parkinson's disease (PD) among suicide victims and the profile of these persons, taking into account suicide attempts, timing of depression and comorbid somatic diseases.

METHODS

The database of this study consisted of suicide victims aged 50 years of age or older (n = 555) during a fourteen-year period in the province of Oulu in Northern Finland.

RESULTS

Hospital-treated Parkinson's disease occurred in 1.6% of the subjects, indicating a rather low prevalence of suicide in this group of patients. The persons with PD had attempted suicide earlier in 44% of the cases, while the corresponding percentage for other victims in older age was 9.9% (p = 0.009 Fischer exact test).

CONCLUSIONS

Based on the case characteristics of our study the profile of PD person who completed suicide was as follows: male subject with recently diagnosed disease, living in rural area, having multiple physical illnesses, and having attempted suicide earlier. Psychiatric consultation is thus highly recommended for the PD patients with this disease profile.

[Which are the recent clinical findings regarding the association between depression and suicide?]

OBJECTIVE

Suicide is one of the leading causes of mortality worldwide, especially among young subjects. Suicide is considered the outcome of a multidimensional and complex phenomenon, which is a result of the interaction between several factors. The association between psychopathology and suicide has been extensively investigated. Major depression plays an important role among the psychiatric diagnoses associated with suicide. This finding seems to be confirmed by different study designs, and in distinct populations. The present paper aims to briefly review the recent findings regarding the suicide-related clinical features of depression. Moreover, strategies for suicide prevention were also reviewed.

REVIEW

Recent references were identified and grouped in order to illustrate the main contributions about depression and suicide. Briefly, the literature review stresses the high prevalence of major depression among subjects presenting suicide behaviors. Psychopathological traits, such as aggression and impulsivity play a relevant role in triggering suicidal behaviors. Strategies for suicide prevention were also reviewed in Brazil and internationally. In general, detection and treatment are effective in reducing suicide rates.

CONCLUSION

Studies regarding suicide behaviors have had a pragmatic approach, and generated a large body of evidence about correlates of suicide. However, these studies have not been able to provide a consistent theoretical explanation for this phenomenon. The recent adoption of modern strategies represents a possibility of enhancing the research capability of such studies. In order to be clinically useful, findings should make it possible to deepen the understanding over the experience of a suicidal person, as well as to design specific strategies for prevention and treatment in population subgroups.

[Assessment of hyper- and hypodopaminergic behaviors in Parkinson's disease]

The common perception that Parkinson's disease patients tend to be depressed, anxious, apathetic and harm-avoiding has currently been challenged by the recognition that they can also exhibit a hedonistic, novelty-seeking personality. Thus, Parkinson's disease patients may indulge in their passions in an irresponsible and disinhibited manner, and engage in repetitive, compulsive behaviors that may be harmful and destructive to their social or professional lives. The dopamine dysregulation syndrome includes hypersexuality, pathological gambling, and compulsive shopping; it is associated with addiction to dopaminergic medication. However, not all behavioral changes are necessarily accompanied by a dopaminergic addiction. After antiparkinson treatment is initiated, patients enter a 'honeymoon period' during which changes in mood and behavior reflect a return to the patients' premorbid personality. The increased motivation and higher level of activity in professional as well as leisure activities are considered positive changes by both the patients and their relatives. With prolonged and increased dopaminergic treatment, these positive behavioral changes can become excessive and evolve into nocturnal hyperactivity and stereotyped, repetitive and time consuming behaviors which ultimately disorganize the patient's everyday routine and herald behavioral addictions. These drug-induced behavioral changes are under-appreciated by neurologists and under-reported by the patients who neither complain about the behaviors nor understand the relationship between motivated behavior and dopaminergic medication. For these reasons, we propose a new scale for the assessment of behavior and mood to quantify and track changes related to Parkinson's disease, to dopaminergic medication, and to non-motor fluctuations. This scale is based on the concept of hypo- and hyperdopaminergic mood and behavior. The scale consists of 18 items addressing non-motor symptoms, grouped in four parts: general psychological evaluation, apathy, non-motor fluctuations and hyperdopaminergic behaviors. The rating in five points (0-4 from absent to severe) is carried out during a semi-structured interview. Open-ended questions introduce each item, allowing patients to express themselves as freely as possible. Close-ended questions permit the rating of severity and intensity. This new instrument can be used by psychologists, psychiatrists or neurologists familiar with Parkinson's disease. Designed to detect changes in mood and behavior of Parkinson's disease patients resulting either from the disease or its treatment, this tool can be used in conjunction with the neurocognitive evaluation, to help tailor the treatment of motor and non-motor symptoms to each individual's needs.

Suicidal ideation in Parkinson's disease

OBJECTIVE

To assess the frequency of suicidal ideation and suicide attempts in patients with Parkinson's disease.

METHODS

The Mini International Neuropsychiatric Interview (MINI), Beck Depression Inventory (BDI), and Hamilton Rating Scale for Depression (HAM-D) were administered to 90 consecutive, non-demented Parkinson's disease patients. They were also submitted to a complete neurologic examination which included brief cognitive batteries, the Mini Mental Status Exam, and Frontal Assessment Battery. We analyzed the scores of the section of the MINI related to the risk of suicide as well as the specific questions of BDI and HAM-D concerning suicidal ideation.

RESULTS

No patient had ever attempted suicide. According to MINI, suicidal ideation was present in 13 patients (14.4%) with Parkinson's disease. All instruments assessed the risk of suicide in a similar way. Suicidal ideation was associated only with lower age (P=.022), lower age of Parkinson's disease onset (P=.021), panic disorder (P=.004), social anxiety disorder (P=.007), and major depression (P<.001). Logistic regression analysis indicated that major depression was the main predictor of suicidal ideation.

CONCLUSION

Suicide attempts seem to be uncommon in Parkinson's disease, despite the fact that the rates of suicidal ideation are possibly elevated. Depression seems to be the most important predictor of suicidal ideation in Parkinson's disease.

Dementia and suicidal behavior: a review of the literature

BACKGROUND

While dementia is more common in older people and suicide rates in many countries are higher among the elderly, there is some doubt about the association between these two phenomena.

METHODS

A search of the major relevant databases was carried out to examine the evidence for this possible association.

RESULTS

The association between dementia and suicide and also non-fatal self-harm did not appear strong but many studies have significant methodological limitations and there are few studies of suicide or self-harm in vascular, frontotemporal, Lewy body and HIV dementia where such behavior might be expected to be more common. Rates of self-harm may be increased in mild dementia and are higher before than after predictive testing for Huntington's disease. Overall, the risk of suicide in dementia appears to be the same or less than that of the age-matched general population but is increased soon after diagnosis, in patients diagnosed with dementia during hospitalization and in Huntington's disease. Putative risk factors for suicide in dementia include depression, hopelessness, mild cognitive impairment, preserved insight, younger age and failure to respond to anti-dementia drugs. Large, good quality prospective studies are needed to confirm these findings.

CONCLUSIONS

Further research should be undertaken to examine how rates of suicide and self-harm change during the course of the illness and vary according to the specific sub-type of dementia.

Suicidal and death ideation in Parkinson's disease

Parkinson's disease (PD) is a chronic, disabling illness affecting primarily the elderly and is associated with a high prevalence of depression. Although these are known risk factors for suicidal and death ideation, little is known about the prevalence and correlates of such ideation in PD. A convenience sample of 116 outpatients with idiopathic PD at two movement disorders centers were administered a modified Paykel Scale for suicidal and death ideation, as well as an extensive psychiatric, neuropsychological, and neurological battery. Univariate and multivariate logistic regression models were used to determine the correlates of suicidal or death ideation. Current death ideation (28%) or suicide ideation (11%) were present in 30% of the sample, and 4% had a lifetime suicide attempt. On univariate logistic regression analysis, increasing severity of depression (odds ratio = 2.92, 95% CI 2.01-4.24, P < 0.001), impulse control disorder (ICD) behaviors sometime during PD (odds ratio = 6.08, 95% CI 1.90-19.49, P = 0.002), and psychosis (odds ratio = 2.45, 95% CI 1.05-5.69, P = 0.04) were associated with either ideation. On multivariate logistic regression analysis, only increasing severity of depressive symptoms (odds ratio = 2.76, 95% CI 1.88-4.07, P < 0.001) predicted suicidal or death ideation. In conclusion, active suicidal or death ideation occurs in up to one-third of PD patients. Comorbid psychiatric disorders, more than PD-related disease variables, are associated with this ideation, highlighting the need for a comprehensive approach to the clinical care of PD patients.

Suicide among patients with amyotrophic lateral sclerosis

Studies on the suicide risk among patients with amyotrophic lateral sclerosis (ALS) in countries without legalized euthanasia or assisted suicide are important additions to data on the wish to die of these patients. We conducted a population-based cohort study in Sweden between 1965 and 2004, which comprised of 6,642 patients with incident ALS identified from the Swedish Inpatient Register. We calculated the standardized mortality ratios (SMRs) of suicide among the patients using the suicide rates of the general Swedish population as a reference. In total, 21 patients committed suicide during follow-up, compared to the predicted 3.6 suicides. Thus, we noted an almost 6-fold increased risk for suicide among ALS patients [SMR 5.8, 95% confidence interval (CI) 3.6-8.8]. Patients who committed suicide were, on average, around 7 years younger at the time of their first period of hospitalization than patients who did not commit suicide. The highest relative risk for suicide was observed within the first year after the patient's first period of hospitalization (SMR 11.2, 95% CI 5.8-19.6). After that, the relative risks decreased with time after hospitalization (P-value for trend = 0.006), but remained elevated 3 years later. The relative risks of suicide among ALS patients did not show a clear trend over time in contrast to the decreasing trend of relative risks for suicide among patients with cancer during the same period. Patients with ALS are at excess risk of suicide in Sweden and the relative risk is higher during the earlier stage of the disease.

Suicide risk among inpatients at a university general hospital

OBJECTIVE: To estimate the proportion of inpatients at a university general hospital who are at risk of committing suicide. METHOD: A random sample of 253 patients (57% males) aged 18 years old or older, admitted to surgical and clinical wards, was assessed using the the Mini International Neuropsychiatric Interview, which has a section that evaluates the risk for suicide. Uni- and multivariate analyses were performed. RESULTS: There were 58 (23%) patients with a risk for suicide, 13 (5% of total) of whom presented a high risk. The prevalence of suicide risk was greater in young adult patients, those with no matrimonial relationship and those diagnosed with major depression (univariate analysis, Chi-squared test; p = 0.01, 0.03 and 0.0001, respectively). The multivariate analysis revealed that the risk for suicide in individuals younger than 30 years old was two fold higher than in those individuals between the ages of 30 and 59 years (OR = 0.45, 95% CI = 0.22-0.93; p = 0.03) and four fold greater than in those who were 60 years old or older (OR = 0.25, 95% CI = 0.1-0.64; p = 0.004). CONCLUSION: When young adults are admitted to general hospitals they should receive special attention due to their suicidal potential.

Coping and quality of life in one hundred and thirty five subjects with multiple sclerosis

INTRODUCTION

and objective The aim of this study was to compare coping strategies and quality of life (QoL) in multiple sclerosis (MS), as they relate to the course of the disease (relapsing-remitting (RR), secondary progressive (SP), primary progressive (PP)), while taking depression and anxiety into account.

METHODS

A total of 135 MS subjects were seen for a semi-structured interview in order to collect socio-demographic and clinical information, after which there was an assessment of their mental and cognitive states (Mini International Neuropsychiatric Interview (MINI), Montgomery and Asberg Depression Rating Scale (MADRS), Depressive Mood Scale (EHD), Hamilton Anxiety (HAMA), Frontal Assessment Battery (FAB)). All subjects then completed three self-report questionnaires; two about coping strategies (Ways of Coping Checklist (WCC), Coping with Health, Injuries and Problems Scale (CHIP)) and one about QoL (SEP59).

RESULTS

The mental health (depression and anxiety) and the psychological and social dimensions of QoL were relatively unaffected. However, after controlling for age and disability, the disease course had a strong effect on both mental health and QoL, with the poorest condition for SPMS and the best condition for PPMS. The SPMS patients tend to use emotional coping strategies extensively, while the PPMS patients use more instrumental strategies.

DISCUSSION

Our study clearly demonstrated that psychological and social well-being were substantially affected by the disease course. These results encourage us to develop interventions focused on coping strategies and which are better adapted to individual patients.

Mortality in patients with Parkinson's disease treated by stimulation of the subthalamic nucleus

Subthalamic nucleus (STN) stimulation improves motor disability and quality of life in patients with advanced Parkinson's disease (PD). Short-term mortality is low, but little is known about long-term mortality. We assessed mortality and causes of death in 171 consecutive PD patients treated by STN stimulation. Surgery was performed after a median lagtime of 13 years from PD onset at a median age of 57 years. The median follow-up after surgery was 41 months. Sixteen patients died 8 to 83 months after neurosurgery. Poorer cognitive function was the only predictive factor for mortality (standardized mortality ratio = 2.9; 95% confidence interval [CI], 1.6-4.7; P < 0.0001). Based on a historical comparison of 118 operated patients with 39 nonoperated patients from a different population, survival among operated patients was not better (hazard ratio = 1.2; 95% CI, 0.7-2.1).

Cognitive, Affective, and Psychiatric Features of Parkinson's Disease

Nonmotor symptoms, including cognitive deterioration and dementia, depression and apathy, and psychosis, are common in Parkinson's disease. Their presence is associated with a tremendous burden for the patient and family members. This article reviews the pathophysiololgy, risks, impact, major features, diagnosis, and treatment of these symptoms in Parkinson's disease.

Treatment of depression in Parkinson's disease

Depression is one of the most common nonmotor features observed in Parkinson's disease (PD), affecting approximately 40% of patients. Depression in Parkinson's disease (dPD) significantly affects quality of life of both patients and their families and has been shown to be more predictive of distress than motor disability. Depression frequently goes unrecognized in this population, however, in part because the diagnosis is often complicated by the overlap of psychiatric and PD symptoms. The etiology of dPD is unclear; dopaminergic, serotonergic, and noradrenergic systems may be implicated. Options for managing dPD include antidepressant medication; cognitive-behavioral therapy; behavioral lifestyle interventions such as exercise; and, in refractory cases, noninvasive brain stimulation (electroconvulsive therapy, transcranial magnetic stimulation). Randomized controlled trials are needed to evaluate the efficacy of interventional approaches for dPD; several trials are currently underway.

The Effect of Hospitalization with Medical Illnesses on the Suicide Risk in the Oldest Old: A Population-Based Register Study

OBJECTIVES

To compare the effect of hospitalization with medical illnesses on the suicide risk in the oldest old (> or = 80) with that in the old (65-79) and middle-aged (52-64) using nationwide data.

DESIGN

Event-history analysis using time-varying covariates based on prospective individual-level register data.

SETTING

Population-based record linkage.

PARTICIPANTS

All persons aged 52 and older living in Denmark during 1996 to 1998 (N=1,684,205).

MEASUREMENTS

The studied event is completed suicide. The following time-varying variables are included in the analysis: current age, hospitalization with medical illnesses within previous 2 years, and number of different medical diagnoses given at hospitalizations within previous 2 years. Relative suicide risks were calculated using event-history analysis. The proportional attributable risk was calculated to assess to which extent hospitalization can explain the increased suicide risk in the oldest old.

RESULTS

During the 3-year study period, 1,184 persons committed suicide. Hospitalization with medical illnesses was associated with an increased suicide risk in the study population. The highest suicide rates were found in the oldest-old men who had been hospitalized during the previous 2 years: 113 per 100,000 versus 80 per 100,000 in the general population of men aged 80 and older. Also, the oldest-old women with a history of hospitalization had a higher suicide rate than their peer group. Nevertheless, the oldest old experienced a lower increase in risk after hospitalization than the middle-aged. Experiencing three or more different diagnoses increased the risk further. Almost two-thirds of the oldest old who committed suicide had experienced a medical hospitalization during a 2-year period preceding the suicide. A substantial part of the greater suicide rate in the oldest old than in the middle-aged can be attributed to the increased prevalence of medical hospitalization.

CONCLUSION

The oldest old who have been hospitalized with medical illnesses have a significantly higher suicide risk than people in the same age range with no hospitalization, although they experience a lower increase in risk after hospitalization than the middle-aged. The increased prevalence of medical illnesses explains a part of the greater suicide risk with age, especially for the oldest old women. Considering that hospitalization with medical illness often precedes suicide in the oldest old, hospitalization may play an important role in identification of suicidal ideation in older people.

Neuropsychiatric aspects of Parkinson's disease: recent advances

Psychiatric disturbances are a common feature of Parkinson's disease (PD), which is a degenerative disorder defined by its characteristic movement abnormalities. Its management is optimal when PD is viewed as a neuropsychiatric disorder, because this encourages consideration of the motor deficits along with its psychiatric and cognitive aspects. This review addresses the diagnosis and treatment of the most common psychiatric disorders in PD, and provides an update of related clinical research, including studies on neurosurgical treatments.

Suicide in Neurologic Illness

The risk of attempted or completed suicide is increased in patients with migraine with aura, epilepsy, stroke, multiple sclerosis, traumatic brain injury, and Huntington's disease. Contrary to the general perception that the risk of suicide among patients with Alzheimer's disease and other dementing conditions is low, several reports suggest that the risk of suicide in these patients increases relative to the general population. Some patients at risk for neurologic disorders are also at increased risk for suicide; in particular, the risk of suicide is increased among persons at risk for Huntington's disease, independent of the presence or absence of the Huntington's gene mutation. The risk of attempted or completed suicide in neurologic illness is strongly associated with depression, feelings of hopelessness or helplessness, and social isolation. Additional suicide risk factors in persons with neurologic illness include cognitive impairment, relatively younger age (under 60 years), moderate physical disability, recent onset or change in illness, a lack of future plans or perceived meaning in life, recent losses (personal, occupational, or financial), and prior history of psychiatric illness or suicidal behavior. Substance dependence, psychotic disorders, anxiety disorders, and some personality disorders (eg, borderline personality disorder) may also contribute to increased risk of suicide among persons with neurologic illnesses. Identification and aggressive treatment of psychiatric problems, especially depression, as well as reduction of modifiable suicide risk factors among patients with neurologic illness is needed to reduce the risk of attempted and completed suicide in this population.

Postoperative management of subthalamic nucleus stimulation for Parkinson's disease

The postoperative neurologic management of patients with deep brain stimulation (DBS) of the subthalamic nucleus (STN) for Parkinson' s disease is a complex dynamic process that involves a progressive increase in stimulation intensity and a parallel decrease in antiparkinsonian medication while assessing the interactions of both treatments. Neurologists responsible for postoperative management of patients receiving STN DBS must have expert knowledge of the electroanatomy of the subthalamic area and be familiar with the medical treatment of motor and nonmotor symptoms, including the management of long-term complications of levodopa treatment. Neurosurgeons who perform DBS need to understand the principles that guide the postoperative adaptation of treatment. This article defines guidelines for setting stimulation parameters, adapting drugs and managing adverse effects.

Are patients with Parkinson's disease suicidal?

Using the National Center of Health Statistics' mortality statistics databases for 1991 through 1996 (12,430,473 deaths), we isolated 144,364 individuals 40 years of age or older with a primary diagnosis of Parkinson's disease (PD). Of these, 122 died by suicide. The rate of suicide in the general population was about 10 times higher than in patients with PD (0.8% compared with only 0.08%, respectively). These different rates of suicide cannot be attributed to differences in age, gender, race, education, or marital status. Compared with patients with suicidal PD, patients with PD who died from other causes manifested significantly lower rates of affective disorders. The referent population exhibited a higher rate of malignancy and a lower rate of depression. The findings suggest that marital status, mood disorder, and somatic comorbidity provide only a limited understanding of completed suicide.

Depression and Huntington's disease: prevalence, clinical manifestations, etiology, and treatment

In order to determine the extent to which depression complicates Huntington's disease (HD), we have analyzed the existing literature on depression in HD in order to report the prevalence, clinical manifestations, and treatment of HD depression. By means of MEDLINE literature searches and reviews of HD articles' bibliographies, we identified for our analysis 16 HD depression studies. Our results indicate that the prevalence of depression is 30% for all HD patients. Clinical manifestations of HD depression include a marked increased risk for suicide. The etiology of HD depression is unclear, but may be due to a number of factors, such as dysfunction in the caudate nucleus, dysfunction in the ventral striatum, and various genetic factors that are discussed in this review. Case reports and case series support the efficacy of standard antidepressant interventions in resolving symptoms of depression. Efficacious treatments reported in the literature include tricyclic antidepressants, monoamine oxidase inhibitors, selective serotonin reuptake inhibitors, and electroconvulsive therapy. In this study, the successful anecdotal treatment of seven consecutive HD depressed patients with sertraline suggests that sertraline may be a safe and efficacious treatment of HD depression.

The personality associated with Parkinson's disease

Since at least 1913 reports have suggested there are personality traits and behaviors that are found premorbidly in those who go on to develop Parkinson's disease (PD). This premorbid personality consists of traits such as industriousness, punctuality, inflexibility, cautiousness, and lack of novelty seeking and persists after the onset of the motor illness. The existence of this personality remains controversial but is supported by case-based anecdotes, twin studies, and comparison of patients with PD with medical control patients on standardized instruments. In addition a large number of epidemiologic studies show that people who develop PD have low lifetime risks for cigarette smoking, coffee drinking, and alcohol consumption, again suggesting that there is a behavior pattern that predates PD. Despite the retrospective nature of much of these data, the use of nonstandardized instruments, and diffuse concepts of personality, the great majority of studies show striking similarity in identifying these traits. An integrating hypothesis, involving damage to dopaminergic systems, known to predate the onset of the motor illness, is discussed.

Neuropsychiatric aspects of Parkinson's disease

Previous studies of the neuropsychiatric aspects of Parkinson"s disease were frequently methodologically inadequate. Small sample sizes, selection bias, lack of diagnostic criteria of Parkinson"s disease, different definitions and assessment of neuropsychiatric symptoms, and lack of control groups seriously questioned the validity of and ability to generalize the results from many studies. During the past decade, however, several of these methodological issues have been addressed. Recent studies have found that mild cognitive impairment is very common, and dementia, depression, and psychotic symptoms develop in a large proportion of patients. Neuropsychiatric symptoms are important determinants of mortality and disease progression, as well as of the patients quality of life and course of disease, caregiver distress, and nursing home admission. Few adequately designed treatment trials have been published, but available evidence suggests that depression and hallucinations may be effectively treated using new antidepressants and atypical antipsychotic agents without worsening of parkinsonism.

Alterations in phosphoinositide signaling and G-protein levels in depressed suicide brain

The function of the phosphoinositide signal transduction system and the levels of heterotrimeric G-protein alpha-subunits were examined in postmortem prefrontal cortex regions (8/9) and region (10) from suicide victims with major depression and matched control subjects without psychiatric illness. The hydrolysis of [3H]phosphatidylinositol (PI) stimulated by phospholipase C, GTP-gamma-S, NaF, and neurotransmitter receptor agonists was measured in membrane preparations from both groups. Phospholipase C-beta activity was similar in depressed suicide and control subjects in the two regions of prefrontal cortex. In prefrontal cortex (10), but not in (8/9), the GTP-gamma-S concentration-dependent stimulation of [3H]PI hydrolysis was significantly lower (30%) in the depressed suicide group compared to the control group. Receptor-coupled, G-protein-mediated [3H]PI hydrolysis induced with carbachol, histamine, trans-1-aminocyclopentyl-1, 3-dicarboxylic acid (ACPD, a glutamatergic metabotropic receptor agonist), serotonin, or 2-methylthio-adenosine triphosphate (2mATP, a purinergic receptor agonist) in the presence of GTP-gamma-S stimulated equivalent responses in the two groups of subjects in each brain region. In prefrontal cortex (10) there was a 68% increase in the level of the 45 kDa subtype of G alpha s and in prefrontal cortex (8/9) there was a significant decrease (21%) in the level of G alpha i2 in the depressed suicide group compared to the control group. Levels of other heterotrimeric G-protein alpha-subunits (G alpha q/11, G alpha i1, and G alpha o) were not different in depressed suicide and control subjects in either brain region. Moreover, there were no differences in the levels of phospholipase C-beta or protein kinase C-alpha in the two groups of subjects in either brain region examined. These results demonstrate that in the prefrontal cortex of suicide victims with major depression compared to normal control subjects there is a region-specific alteration of G-protein-induced activation of the phosphoinositide signal transduction system and in the levels of G-protein alpha-subunits involved in cyclic AMP synthesis. These findings provide direct evidence in human brain that these two important signal transduction systems are altered in suicide subjects with major depression.

A study of cognitive functions in young Parkinsonian patients

The purpose of the study was to evaluate the neuropsychological performance of younger Parkinson's disease (PD) patients compared to healthy controls. A group of young optimally treated PD patients younger than 56 years was pair-matched with a group of healthy controls for age, social class and the two WAIS subtests "vocabulary" and "similarities". As a group, the PD patients were satisfactory in verbal logical intelligence, but evaluation of neuropsychological tests showed difficulties in short memory span, constructional function and logical visual sequential cognition. Young PD patients have some cognitive impairment for which they are able to compensate for a time because of preserved intelligence. More attention should be paid to possible problems in their jobs and social life.

Mortality in patients with Parkinson's disease

INTRODUCTION

After the introduction of L-dopa the mortality rate in Parkinson's disease (PD) patients has changed, but is still higher than in the background population.

MATERIAL & METHODS

Mortality, age at death and cause of death in a group of PD patients compared with the background population were studied. The diagnosis on the death certificate were registered. The material consisted of 458 patients who in a period 1.4.1973-31.10.1991 were registered as having PD.

RESULTS

Death in the period amounted to 253 patients. Median age of death was 77.29 years for men and 79.11 years for women. In the background population the median age at death was 80.69 years for men and 84.37 years for women. The SMR for men was 1.92 and for women 2.47. Infections, in particular lung infections, and heart diseases were the most common causes of death. Seventy percent of the death certificates had PD as a diagnosis.

CONCLUSION

It is likely that several factors can influence the changed mortality of PD: more effective treatment, changing diagnostic practice, and inter-disease competition.