SSRIs do not worsen Parkinson's disease: evidence from an open-label, prospective study

Antidepressant medication use and restless legs syndrome in patients presenting with insomnia

BACKGROUND AND PURPOSE

Restless legs syndrome (RLS) is a movement disorder that frequently results in significant complaints of insomnia. Based on published case reports, it is commonly believed that RLS can be caused or exacerbated by antidepressant agents, thus complicating the treatment of depressed patients who are already prone to sleep disturbances. However, there are no systematic studies demonstrating an association between the clinical diagnosis of RLS and the use of antidepressant medication.

PATIENTS AND METHODS

Retrospective chart review of 200 consecutive patients presenting for evaluation of sleep initiation insomnia at an accredited freestanding sleep disorders center that is part of an integrated health care system.

RESULTS

Mean age (+/-SD) of patients was 51.1+/-14.8 years; 60% were women. Fifty-six percent carried a diagnosis of depression, 38% were being treated with antidepressant medication at presentation and 45% met clinical diagnostic criteria for RLS. There were no statistical associations, either by chi(2) analysis or odds ratios, between RLS and antidepressant use or use of any specific class of antidepressant. Positive associations with RLS were found for patients receiving treatment for hypothyroidism and those taking estrogens; a significant negative association was found for patients receiving beta adrenergic antagonists.

CONCLUSIONS

Although there are anecdotal reports of antidepressant use causing or exacerbating RLS, systematic study of this issue fails to corroborate an association.

Antidepressants for depressed elderly

BACKGROUND

Depression is a relatively common experience in older adults. The syndrome is associated with considerable distress, morbidity and service commitment. Approximately two thirds of patients presenting with severe forms will respond to antidepressant treatment and the last twenty years has witnessed a great increase in the number of these drugs. Older, frail people are particularly vulnerable to side effects.

OBJECTIVES

The aims of this review were to examine the efficacy of antidepressant classes, to compare the withdrawal rates associated with each class and describe the side effect profile of antidepressant drugs for treating depression in patients described as elderly, geriatric, senile or older adults, aged 55 or over.

SEARCH STRATEGY

The Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register (CCDANCTR-Studies) was searched (2003-08-13). Reference lists of relevant papers and previous systematic reviews were hand searched for published reports and citations of unpublished studies.

SELECTION CRITERIA

Only randomised controlled trials were included. Trials had to compare at least two active antidepressant drugs in the treatment of depression.

DATA COLLECTION AND ANALYSIS

Reviewers extracted data independently. In examining efficacy, the reviewers assumed that people who died or dropped out had no improvement. Withdrawal rates irrespective of cause and specifically due to side effects were compared between drug classes. Relative risk (RR) for dichotomous data and weighted mean difference for continuous data were calculated with 95% confidence intervals (CI). Qualitative side effect data were reported in terms of ratios of side effects and percentage of patients experiencing specific side effects.

MAIN RESULTS

A total of 29 trials provided data for inclusion in the review. We were unable to find any differences in efficacy when comparing classes of antidepressants. However, as the trials contained relatively small numbers of patients, these findings may be explained by a type two error. Tricyclic antidepressants (TCAs) compared less favourably with selective serotonin reuptake inhibitors (SSRIs) in terms of numbers of patients withdrawn irrespective of reason (RR: 1.24, CI 1.04, 1.47) and number withdrawn due to side effects (RR: 1.30, CI 1.02, 1.64). Subgroup analyses demonstrated that TCA related antidepressants had similar withdrawal rates to SSRIs irrespective of reason of withdrawal (RR: 1.49, CI 0.74, 2.98) or withdrawal due to side effects (RR: 1.07, CI 0.43, 2.70). The qualitative analysis of side effects showed a small increased profile of gastro-intestinal and neuropsychiatric side effects associated with classical TCAs.

AUTHORS' CONCLUSIONS

Our findings suggest that SSRIs and TCAs are of the same efficacy. However, we have found some evidence suggesting that TCA related antidepressants and classical TCAs may have different side effect profiles and are associated with differing withdrawal rates when compared with SSRIs. The review suggests that classical TCAs are associated with a higher withdrawal rate due to side effect experience, although these results must be interpreted with caution due to the relatively small size of the review and the heterogeneity of the drugs and patient populations.

Response to 4-month treatment with reboxetine in Parkinson's disease patients with a major depressive episode

OBJECTIVE

The aim of this study is to evaluate response to reboxetine in a 4-month follow-up study on depression in Parkinson's disease (PD), and to assess its tolerability profile.

METHODS

A prospective 4-month follow-up study was performed in 17 PD patients with a major depressive episode. The intensity of depressive symptoms was evaluated mainly with the Hamilton Rating Scale for Depression (HAM-D), and PD was assessed with the Unified Parkinson Disease Rating Scale (UPDRS).

RESULTS

Reboxetine causes a progressive decrease in depressive symptoms in PD patients; the initial score of 16.76 (2.68) on HAM-D decreased to 5.85 (2.42) at 4 months (P < .002). Mean UPDRS scores did not show a statistically significant increase: 18.18 (2.6) at the beginning and 18.25 (2.4) at the end of the follow-up period (P = .8).

CONCLUSIONS

Reboxetine, as first choice treatment for major depressive episodes in PD patients, seems to be effective in progressively improving depressive symptoms over the first 4 months of treatment until complete remission. Reboxetine does not seem to increase PD symptoms, whereas patients' quality of life improves.

Escitalopram for major depression in Parkinson's disease: an open-label, flexible-dosage study

Depression and antidepressant use are common in Parkinson's disease, but the benefit of selective serotonin reuptake inhibitor (SSRI) treatment in this population has not been established. The authors treated 14 Parkinson's disease patients with major depression with escitalopram in an open-label study. Although treatment was well tolerated and correlated with a significant decrease in Inventory of Depressive Symptomatology score, response and remission rates were only 21% and 14%, respectively. However, half of the subjects met Clinical Global Impression-Improvement criteria for response. In Parkinson's disease, either SSRIs may have limited antidepressant effects, or the use of existing depression diagnostic and rating instruments may be problematic.

Effect of repetitive TMS and fluoxetine on cognitive function in patients with Parkinson's disease and concurrent depression

Previous studies show that cognitive functions are more impaired in patients with Parkinson's disease (PD) and depression than in nondepressed PD patients. We compared the cognitive effects of two types of antidepressant treatments in PD patients: fluoxetine (20 mg/day) versus repetitive transcranial magnetic stimulation (rTMS, 15 Hz, 110% above motor threshold, 10 daily sessions) of the left dorsolateral prefrontal cortex. Twenty-five patients with PD and depression were randomly assigned either to Group 1 (active rTMS and placebo medication) or to Group 2 (sham rTMS and fluoxetine). A neuropsychological battery was assessed by a rater blind to treatment arm at baseline and 2 and 8 weeks after treatment. Patients in both groups had a significant improvement of Stroop (colored words and interference card) and Hooper and Wisconsin (perseverative errors) test performances after both treatments. Furthermore, there were no adverse effects after either rTMS or fluoxetine in any neuropsychological test of the cognitive test battery. The results show that rTMS could improve some aspects of cognition in PD patients similar to that of fluoxetine. The mechanisms for this cognitive improvement are unclear, but it is in the context of mood improvement.

Acute effects of selective serotonin reuptake inhibitors on neuroleptic-induced catalepsy in mice

Depression found in Parkinson disease (PD) usually responds to selective serotonin reuptake inhibitors (SSRIs). Drugs that modify experimental neuroleptic catalepsy (NC) might affect extrapyramidal symptoms in PD. Therefore, the effects of SSRIs on NC were tested in mice, 26-36 g, separated by sex. Catalepsy was induced with haloperidol (H; 1 mg/kg, ip) and measured at 30-min intervals using a bar test. An SSRI (sertraline, ST; paroxetine, PX; fluoxetine) or vehicle (C) was injected ip 30 min before H. Dunnett's test was used for comparison of means. ST (1-5 mg/kg) or PX (1-5 mg/kg) attenuated NC, with a similar inhibition found in both sexes (5 mg/kg, 180 min: ST - males: 124 +/- 10 vs 714 +/- 15 s in C; females: 116 +/- 10 vs 718 +/- 6 s in C; PX - males: 106 +/- 10 vs 714 +/- 14 s in C; females: 102 +/- 10 vs 715 +/- 14 s in C). At 0.3 mg/kg, neither of these drugs affected NC. Fluoxetine (1-25 mg/kg) also inhibited catalepsy, although the effect was not dose-dependent; no differences were observed between males and females (5 mg/kg, 180 min: males, 185 +/- 14 vs 712 +/- 14 s in C; females, 169 +/- 10 vs 710 +/- 19 s in C). For these SSRIs, maximal inhibition of NC was obtained with 5 mg/kg, 180 min after H. These results are consistent with the hypothesis that serotonergic mechanisms modulate nigrostriatal transmission, and suggest that SSRIs are possibly safe in depressive PD patients.

The effect of depression on motor function and disease severity of Parkinson's disease

OBJECTIVES

Approximately 40% of patients with Parkinson's disease (PD) experience symptoms of depression. Our aim was to evaluate the effect of depression on disease severity, motor function and other phenotypic characteristics of PD.

PATIENTS AND METHODS

We studied 32 PD patients with major depression (PD-D) according to the DSM-IV criteria and 32 PD patients with no depression (PD-C) matched for gender, age of onset and duration.

RESULTS

Major depression in PD patients was associated with increased disease severity, poorer motor function and worse performance in the activities of daily living as measured by UPDRS scores. Furthermore, there was an association of depression with the severity of bradykinesia and axial rigidity.

CONCLUSIONS

Depression in PD can have a profound negative impact on a patient's sense of wellbeing and motor functioning. Therefore, PD patients should be routinely and carefully screened for the presence of depression and appropriate management should be considered. Larger studies on the subject are warranted.

Antidepressant studies in Parkinson's disease: a review and meta-analysis

The objective of this study was to determine effect sizes for both antidepressant treatment and placebo for depression in Parkinson's disease (PD), and to compare the findings with those reported in elderly depressed patients without PD. Recent reviews have concluded that there is little empiric evidence to support the use of antidepressants in PD; however, available data has not been analyzed to determine the effect size for antidepressant treatment in PD depression. A literature review identified antidepressant studies in PD. Suitable studies were analyzed using meta-analytic techniques, and effect sizes were compared with those from antidepressant studies in elderly patients without PD. Large effect sizes were found for both active treatment and placebo in PD, but there was no difference between the two groups. In contrast, active treatment was superior to placebo in depressed elderly patients without PD. In PD, increasing age and a diagnosis of major depression were associated with better treatment response. Results also suggest that newer antidepressants are well tolerated in PD. Despite the high prevalence of depression and antidepressant use in PD, controlled treatment research has been almost nonexistent. Meta-analysis results suggest a large but nonspecific effect for depression treatment in PD. In addition, PD patients may benefit less from antidepressant treatment, particularly selective serotonin reuptake inhibitors, than do elderly patients without PD.

Current approaches to management of depression in Parkinson’s Disease

Depression is a common problem in patients affected by Parkinson's Disease (PD). In many cases, treatment with antidepressants is necessary, and the choice of the most suitable drug is often controversial, as many factors need to be considered that may complicate the development of the disease, including potential side effects of antidepressant therapy. Selective Serotonin Reuptake Inhibitors (SSRIs) and Tricyclic Antidepressants (TCAs) are the two major categories of antidepressants used. Tricyclics have been shown to be effective in most cases, but some side effects (orthostatic hypotension, sedation, cognitive and anticholinergic effects) may present problems. In contrast, SSRI appear to be better tolerated, but some reports indicate a potential worsening of the parkinsonism. Other recently introduced medications need further investigation. The main therapeutic strategies, as reported in the international literature according to efficacy and tolerability, interactions with antiparkinsonian or concomitant drugs and possible effects on worsening of PD, are presented.

Treatment of depression in the medically ill

Most studies on treatment methods in elderly depressive patients have included primarily patients in good physical health, excluding medical comorbidity, despite the fact that depression with medical comorbidity is the norm rather than the exception. In addition, depression is known to increase disability and mortality among the medically ill. This, therefore, becomes an extremely important issue. Although data are limited, the available evidence suggests that depression concomitant with medical illness can be treated. One or more of the selective serotonin reuptake inhibitors have demonstrated potential usefulness in depressed patients with ischemic heart disease, diabetes, dementia, and Parkinson's disease and in patients after stroke and after myocardial infarction. Large-scale trials are needed to assess not only the safety and effectiveness of agents for the treatment of depression in comorbid illness, but also the effects of depression on the course of the medical illness itself.

Treatment of behavioural symptoms and dementia in Parkinson's disease

Behavioural symptoms such as anxiety, depression and psychosis are common in Parkinson's disease (PD), and dementia occurs in about 90% of the patients. These symptoms can be more disabling than the motor dysfunction and they negatively impact quality of life, increase caregiver distress and are more frequently associated with nursing home placement. Depression can be treated with counselling and pharmacotherapy. Tricyclic antidepressants or selective serotonin reuptake inhibitors are widely used, but there is still need for controlled clinical trials. Management of psychosis in PD is complex and includes elimination of identifiable risk factors, reduction of polypharmacy and administration of atypical neuroleptics, which can alleviate psychotic symptoms without worsening motor functions. Clozapine is the best documented atypical neuroleptic shown to be effective against psychosis in PD patients. Cholinesterase inhibitors may prove additional benefit in psychotic PD patients. Recent evidence from small double-blind and open-label trials suggests that cholinesterase inhibitors may be effective in the treatment of dementia associated with PD.

The neuropsychiatry of Parkinson's disease and related disorders

Parkinson's disease is associated with classical Parkinsonian features that respond to dopaminergic therapy. Neuropsychiatric sequelae include dementia, major depression, dysthymia, anxiety disorders, sleep disorders, and sexual disorders. Panic attacks are particularly common. With treatment, visual hallucinations, paranoid delusions, mania, or delirium may evolve. Psychosis is a key factor in nursing home placement, and depression is the most significant predictor of quality of life. Clozapine may be the safest treatment for psychotic features, but more research is needed to establish the efficacy of antidepressant treatments. Dementia with Lewy bodies, the second most common dementia in the elderly, may present in association with systematized delusions, depression, or RBD. Early evidence suggests the utility of rivastigmine, donepezil, low-dose olanzapine, and quetiapine in treating DLB. Parkinson-plus syndromes generally lack a good response to dopaminergic treatment and evidence additional features, including dysautonomia, cerebellar and pontine features, eye signs, and other movement disorders. MSA is associated with dysautonomia and RBD. SND (MSA-P) is associated with frontal cognitive impairments, but dementia, psychosis, and mood disorders have not been strikingly apparent unless additional pathological findings are present. In SDS (MSA-A), impotence is almost ubiquitous; urinary incontinence is frequent; depression is occasional, and sleep apnea should be treated to avoid sudden death during sleep. OPCA neuropsychiatric correlates await further definition. Progressive supranuclear palsy neuropsychiatric features include apathy, subcortical dementia, pathological emotionality, mild depression and anxiety, and lack of appreciable response to donepezil. CBD usually is recognized by early frontal dementia with ideomotor apraxia, often in the right upper extremity, attended later by poorly responsive unilateral Parkinsonism, with additional signs including cortical reflex myoclonus, limb dystonia, alien limb, oculomotor apraxia when asked to look horizontally, depression, personality changes, and, occasionally, Kluver-Bucy syndrome. The neuropsychiatry of FTDP-17 involves apraxia, executive impairment, personality changes, hyperorality, and occasional psychosis. Future research in these Parkinsonian disorders should target the characterization of neuropsychiatric sequelae and their treatment.

Psychiatric aspects of Parkinson's disease--an update

In patients with Parkinson's disease (PD) disturbances of mental state constitute some of the most difficult treatment challenges of advanced disease, often limiting effective treatment of motor symptoms and leading to increased disability and poor quality of life. This article provides an update on the current knowledge of these complications and the use of old and new drugs in their management. Mental state alterations in PD include depression, anxiety, cognitive impairment, apathy, and treatment-related psychiatric symptoms. The latter range from vivid dreams and hallucinations to delusions, manic symptoms, hypersexuality, dopamine dysregulation syndrome and delirium. While some of these symptoms may be alleviated by anti-parkinsonian medication, especially if they are off-period related, treatment-related phenomena are usually exacerbated by increasing the number or dosage of antiparkinsonian drugs. Elimination of exacerbating factors and simplification of drug regimes are the first and most important steps in improvement of such symptoms. However, the advent of atypical antipsychotics such as clozapine has dramatically helped the management of treatment-related psychiatric complications in PD. In patients with dementia associated with PD cognitive functioning and behavioural problems appear to respond to cholinesterase inhibitors, such as rivastigmine or donepezil. Depression is a common problem in early as well as advanced PD, and selective serotonin reuptake inhibitors, reboxetine, and tricyclic antidepressants have been reported to be effective and well tolerated antidepressants. Randomised, controlled studies are required to assess the differential efficacy and tolerability of antidepressants in patients with PD, including the newer antidepressants with serotonergic and noradrenergic properties.

Behavioral disturbances in Parkinson's disease

Treatment of Parkinson's disease (PD) is complex and often involves addressing behavioral changes in addition to the movement disorder. Patients with PD are susceptible to any psychiatric condition seen in the general population; some disorders, such as depression and anxiety, may result from PD-related neuropathological changes. Medicationrelated hallucinations are seen in many PD patients who are treated with dopaminergic agents for motor symptoms. Cognitive impairment is also seen and can be multifactorial. Treatment of behavioral symptoms in PD can greatly improve patients“ overall function and quality of life. As surgical interventions to treat motor symptoms, such as deep brain stimulation of the subthalamic nucleus of the substantia nigra, become more prevalent, the behavioral effects of these procedures must also be addressed,

Treatment of depression in Parkinson's disease

Depression is an important and common nonmotor feature of Parkinson's disease (PD) that is associated with significant disability and a negative impact on quality of life. The physician should remain vigilant for symptoms of depression as they may be mistaken for the progression of Parkinson's disease itself. Transient dysphoria that occurs during 'off' periods in fluctuating PD patients must be distinguished from true depression. Antidepressant therapy should be instituted if depression is interfering with the patient's daily function. The use of serotonin reuptake inhibitors and tricyclic antidepressants in the treatment of depression in PD is widespread in clinical practice. Dopamine agonists may be effective in the treatment of milder depression as well. Individual or family counseling may be helpful. In patients with severe depression who are refractory to antidepressant medications, a series of electroconvulsive treatments can be lifesaving. Nonconventional therapies such as transcranial magnetic stimulation are being investigated.

Guideline for the management of late-life depression in primary care

OBJECTIVE

To develop a guideline for the primary care management of depression in later life based on best practice.

METHOD

Source material included relevant guidelines, literature reviews and consensus documents coupled with an updated literature review covering 1998-October, 2001. This material was summarised as a series of evidence-based statements and recommendations agreed by consensus.

RESULTS

Good quality evidence exists for the pharmacological and psychological treatment of depressive episode (major depression), although not specifically in primary care. There is some evidence of efficacy of antidepressants in late-life dysthymia and minor depression associated with poor functional status. In depressive episode, current evidence suggests acute treatment for at least six weeks and a continuation period of at least 12 months. Both tricyclic antidepressants and Selective Serotonin Re-uptake Inhibitors are effective in longterm prevention. There is less data on how to manage patients who do not respond in the acute treatment phase. More data is needed on sub-groups of patients with specific co-morbid medical conditions and those who are frail. Collaborative care is effective in older depressed primary care patients.

CONCLUSIONS

There are effective treatments for depression in primary care. More research is needed to address the optimum treatment of depression with medical co-morbidity and to elucidate the role of newer psychological interventions. Collaborative care between primary care and specialist services is a promising new avenue for management.

Recognition and treatment of depression in Parkinson's disease

Depression in Parkinson's disease (PD) is common, but little is known about its recognition and treatment. The authors report the antidepressant experience (N = 100) and outcome of depression assessment (n = 77) of a convenience sample of patients at a PD center. Subjects were assessed with a psychiatric and neurological battery, and information was gathered on depression treatment. One third (34%) of subjects met criteria for a depressive disorder, and two thirds (65%) of them were not currently receiving antidepressant treatment. Approximately one quarter (23%) of subjects were taking an antidepressant, but almost half (47%) of them still met criteria for a depressive disorder. Few antidepressant users with persistent depression had received either antidepressant treatment at dosages within the highest recommended range (11%) or more than 1 antidepressant trial (33%). Most depressed patients are untreated, and half of antidepressant users remain depressed, suggesting that even when delivered, treatment is often inadequate or ineffective.

Prevalence, etiology, and treatment of depression in Parkinson's disease

Parkinson's disease (PD) is primarily a disease of elderly individuals with a peak age at onset of 55 to 66 years. It is characterized by bradykinesia, rigidity, tremor, and postural instability; and affects approximately 1 million individuals in the US and is the second most common neurodegenerative disease next to Alzheimer's disease. The motor symptoms of PD are the focus of pharmacotherapy, yet the nonmotor symptoms (e.g., dementia, psychosis, anxiety, insomnia, autonomic dysfunction, and mood disturbances) can be the most disturbing, disabling, and misunderstood aspects of the disease. Depressive symptoms occur in approximately half of PD patients and are a significant cause of functional impairment for PD patients. There is accumulating evidence suggesting that depression in PD is secondary to the underlying neuroanatomical degeneration, rather than simply a reaction to the psychosocial stress and disability. The incidence of depression is correlated with changes in central serotonergic function and neurodegeneration of specific cortical and subcortical pathways. Understanding comorbid depression in PD may therefore add to the understanding of the neuroanatomical basis of melancholia.

Safety of antidepressants in the elderly

Until the 1980s, the two major classes of antidepressants, the tricyclics and the monoamine oxidase inhibitors (MAOIs), were effective but had severe side effects, requiring monitoring by psychiatrists. The past several years have brought new classes of antidepressants that are safer for the patient to take and far easier for the non-psychiatrist to prescribe. Whilst this is of enormous value, it leaves the physician with the dilemma of which one to prescribe. These new antidepressants cannot safely be used interchangeably. This paper will discuss each of the antidepressants presently available, with particular emphasis on safety in the elderly. Drug interactions, side effects and particular challenges to the older patient will be described. The authors will then advise a general strategy for prescribing antidepressants.

Risk of serious extrapyramidal symptoms in patients with Parkinson's disease receiving antidepressant drugs: a pharmacoepidemiologic study comparing serotonin reuptake inhibitors and other antidepressant drugs

To compare the risk of occurrence of "serious" extrapyramidal symptoms (EPS) between selective serotonin reuptake inhibitors and other antidepressant drugs in patients with Parkinson's disease (PD), the authors performed a retrospective study using the French Pharmacovigilance Database (i.e., the database recording all serious adverse drug reactions reported in France by physicians to the National French Pharmacovigilance Network). Patients with PD were identified from the case reports including at least one antiparkinsonian drug (except anticholinergics). The authors studied patients with PD exposed to at least one antidepressant (classified as imipraminics, selective serotonin reuptake inhibitors, or "other") drug. EPS were defined as aggravation of the parkinsonian symptoms. Of the76,640 case reports registered in the database between January 1, 1995, and December 31, 2000, 916 were identified as patients treated with at least one antiparkinsonian drug, including 199 treated with antidepressant drugs. Among them the authors found nine case reports of EPS (i.e., 4.5% of the patients with PD treated with at least one antidepressant). The odds ratio for EPS was 2.18 (0.47-11.35) for selective serotonin reuptake inhibitors, 1.17 (0.22-5.50) for imipraminics, and 0.74 (0.10-4.06) for other antidepressants. This study failed to find any significant difference in the occurrence of serious EPS according to the different classes of antidepressant drugs in patients with PD treated with dopaminergic antiparkinsonian drugs.

Psychiatric symptoms in Parkinson's disease

Aside from the well-known triad of resting tremor, postural instability, and bradykinesia, Parkinson's disease (PD) patients may also develop psychiatric illness as a part of their disease. The psychiatric symptoms may be as disabling as the movement disorder, but are often amenable to treatment. We review the most recent investigations of mood disorders, anxiety disorders, and hallucinations/ psychosis in PD. We then highlight new treatment studies for hallucinations/psychosis in PD.

Parkinson's disease: medical treatment of moderate to advanced disease

Parkinson's disease, a common neurodegenerative disorder, results in significant morbidity 10 to 15 years after disease onset and increased mortality. Levodopa is the mainstay of therapy and provides benefit for the duration of the illness. However, within 5 years, up to 50% of individuals develop fluctuations, including dyskinesias, wearing off, and "on/off" effects. Optimal management of Parkinson's disease patients requires careful titration of medications, with use of polypharmacy, including levodopa, dopamine agonists, catechol-O-methyltransferase inhibitors, amantadine, and anticholinergics in order to maintain good motor function and quality of life. With advancing disease, problems such as dysphagia, dysarthria, and gait and balance abnormalities occur, which are not responsive to dopaminergic medication. Due to extradopaminergic neuronal system degeneration, autonomic dysfunction can also be prominent. Recognition and management of these problems is helpful in improving quality of life in late-stage disease. In very late stages, dementia may complicate treatment, requiring discontinuation of combination therapy and use of low-dose levodopa with atypical neuroleptics.

Depression in Parkinson's disease

Depression is common in Parkinson's disease (PD), and its identification and treatment are critically important in disease management. Despite depression's high prevalence and major impact on patient quality of life, questions remain regarding its epidemiology and preferred treatment. The authors of this paper summarize available information on the epidemiology of depression in PD, review treatment options, and discuss possible interactions between antidepressants and other agents. This information may help guide clinical treatment and define the need for further studies.