Psychiatric disorders in parkinsonism. 1. Functional illnesses and personality

Depression in Parkinson's disease. The impact of symptom overlap on prevalence

The reported prevalence of depression concomitant with Parkinson's disease varies greatly in the literature, which may partly be explained by symptom overlap. To determine the impact of symptom overlap on the prevalence, the authors tested 100 Parkinson's disease patients for major depression (DSM-III-R) with both a standard, inclusive method and a diagnostic-etiologic, exclusive method. The authors found that the prevalence detected with the inclusive method (23%) decreased when the exclusive method was used (13%), which was mainly caused by lower scores on the item "loss of interest." The study's findings give empirical support for the relevance of the new category in DSM-IV "mood disorder due to a general medical condition."

Depression in Parkinson's disease. Pharmacological characteristics and treatment

Parkinson's disease (PD) is a common neurological illness and various degrees of depression frequently complicate its course. Risk factors for developing depression with PD include right-sided hemiparkinsonism, akinesia, increased severity of disability, anxiety and psychosis. Onset of parkinsonism at a younger age, female gender and the use of levodopa are arguable risk factors. Depression may be difficult to diagnose in patients with PD because the signs of the 2 disorders overlap. In addition, patients with atypical PD more commonly have depression than patients with classical PD presentations. Antidepressant response to antiparkinsonian treatment has been limited. Enhancement of catecholamine levels in the CNS by selegiline (deprenyl), a monoamine oxidase (MAO) type B inhibitor, has shown potential antidepressant as well as neuroprotective effects. Other MAO inhibitors have shown antidepressant efficacy in animal models but have not been well tolerated by patients with PD. A catechol-O-methyltransferase (COMT) inhibitor combined with an MAO inhibitor might synergistically maximise the levels of catecholamines in the CNS. Antidepressant medications used in patients without PD include tricyclic antidepressants (TCAs) and selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitors (SSRIs), but only TCAs have been carefully studied for their antidepressant effects in PD. Electroconvulsive therapy has proven efficacy as antidepressant therapy in patients with PD, and transcranial magnetic stimulation has provided temporary relief of depression under experimental conditions. Adverse effects of polypharmacy in the attempted treatment of depression in patients with PD are common in the elderly. A 'serotonin syndrome' has occurred frequently enough to preclude the coadministration of selegiline with SSRIs or TCAs, and multiple interactions between antiparkinsonian and antidepressant medications further complicate treatment strategies in patients with PD. An algorithmic approach to the pharmacological treatment of depression is described in this article.

Differing patterns of psychiatric impairment in Alzheimer and demented parkinsonian patients

Psychiatric symptoms were investigated and compared in 95 patients with Alzheimer type dementia (DAT) and in 39 patients with Parkinson's disease with dementia (PD-D). The diagnosis of the dementia and psychiatric disorders was based on DSM III R criteria; dementia stage was assessed using the Clinical Dementia Rating Scale (CDR). PD-D were significantly older than DAT patients. Delirium was more frequent in the advanced stages of both PD-D and DAT, being mainly of the hypoactive type in PD-D and the hyperactive type in DAT. Delusions and hallucinations predominated in the early CDR stages of both illnesses and did not differ between groups; the same was true for depression. The results revealed different psychopathological profiles in DAT and PD-D patients.

Mixed neurologic and psychiatric disorders: pharmacological issues

The number of patients with mixed neurologic and psychiatric disturbances is large. The psychiatric disturbances are often atypical in presentation and fit poorly into standard psychiatric nomenclature. They can be difficult to treat using standard psychopharmacologic approaches. This report reviews the impact of brain dysfunction on the use of conventional and nonconventional psychotropic agents in this mixed population.

The contribution of constructional accuracy and organizational strategy to nonverbal recall in schizophrenia and chronic alcoholism

The Rey-Osterrieth complex figure was used to assess the separate influences of the constructional accuracy and the organizational strategy employed while copying the figure on the later, incidental recall of the figure. We tested a model, which hypothesized that subjects who copied the main framework of the figure holistically would be more likely to achieve good copy accuracy scores and to reproduce the figure more accurately at recall than subjects who used a piecemeal approach during copy. Subjects included 68 detoxified, chronic alcoholics (ALC), 28 patients with schizophrenia (SZ), and 69 normal control subjects (NCS). The results showed that the ALC and the SZ groups, on average, had lower accuracy and strategy scores at copy than did the NCS group, and furthermore, that the combined contributions of copy accuracy and copy strategy accounted for group differences at recall. A path analysis revealed that, for all three groups, copy strategy had a significant direct effect on copy accuracy. Moreover, copy accuracy and copy strategy made independent contributions to recall accuracy within the ALC and NCS groups; by contrast, within the SZ group, copy strategy made an independent contribution to recall performance but copy accuracy did not. These results suggest that (1) organizational strategy can influence constructional accuracy at both copy and recall; (2) copy accuracy and strategy have the potential to influence recall independently; and (3) the recall deficit in ALC could be attributed to abnormalities in both accuracy and strategy at copy, whereas in SZ it could be attributed only to strategy abnormalities. The deficits observed on the complex figure test in the ALC and SZ were primarily nonmnemonic and were related to ability in figure construction and organizational strategy.

Controlled release of dopamine from a polymeric brain implant: in vivo characterization

Intracerebral microdialysis was used to evaluate the long-term in vivo release of dopamine from ethylene-vinyl acetate (EVAc)-dopamine copolymer matrix discs for up to 65 days following striatal implantation. Dopamine release occurred through a single cavity present on one side of the disc, which was otherwise fully coated with an additional, impermeable layer of EVAc. At 20 days following implantation of the device, extracellular concentrations of dopamine within the striatum reached micromolar levels, over 200-fold greater than control values. Release of dopamine was shown to be stable and maintained for the 2-month duration of the experiment. Histological examination confirmed the biocompatible nature of the implant. There are potential applications of this technology to the treatment of Parkinson's disease and other neurological and psychiatric disorders.

L-tryptophan: a rational anti-depressant and a natural hypnotic?

L-tryptophan is an essential amino acid which is the metabolic precursor of serotonin. Because of the evidence that serotonin deficiency may be an aetiological factor in some sorts of affective disorder and that serotonin is important in the biochemistry of sleep, L-tryptophan has been suggested as a "rational" anti-depressant and as a "natural" hypnotic. This paper reviews the biochemistry and pharmacology of L-tryptophan as well as the literature of the clinical trials that have been conducted with it and suggests that, by itself, L-tryptophan may be useful in mild cases of depression accompanied by endogenous features and cases of bipolar disorder resistant to standard treatments. It also potentiates the monoamine oxidase inhibitors and possibly the serotonergic tricyclic drugs. L-tryptophan may improve the depressed mood of Parkinsonian patients and has a clinically useful hypnotic action. There is evidence it may be useful in organic mental disorders induced by levodopa. Dosage schedules, contraindications and complications are discussed.

Parkinson's disease complicated by anxiety

In a 39-year-old man with Parkinson's disease and a history of anxiety disorders, anxiety-provoking situations such as group psychotherapy precipitated panic attacks and caused pronounced worsening of the parkinsonian symptoms. Extra doses of carbidopa-levodopa failed to control the intensified symptoms. During a 1-month hospitalization period, the anxiety disorders diminished when a combination of psychotherapy, behavioral therapy, and desipramine was used; however, the relationship between increased anxiety and worsened parkinsonian symptoms persisted. In patients with refractory Parkinson's disease, clinicians should consider the possibility of the presence of an anxiety disorder that may be affecting the neurologic condition.