Susceptibility to neuroleptic-induced parkinsonism--age and increased substantia nigra echogenicity as putative risk factors

Transcranial sonography depicts a larger substantia nigra echogenic area in renal transplant patients on calcineurin inhibitors than on rapamycin

BACKGROUND

After kidney transplantation neurologic manifestations may develop, including Parkinson's disease (PD). An enlarged substantia nigra (SN) by transcranial sonography has been recognized as a marker of PD.

METHODS

In renal transplant recipients (RTRs = 95) and controls (n = 20), measurement of mesencephalon, SN, third ventricle, spleen and carotid intima-media thickness (cIMT) and middle cerebral artery (MCA), kidney and spleen arteries Doppler resistive index (RI) were performed.

RESULTS

RTRs had larger SN, third ventricle and cIMT and higher renal RI than controls. The SN was larger in the CNIs group than in controls and rapamycin group, while the third ventricle was similar between patients but larger than in controls. In RTRs, SN showed a direct linear correlation with spleen and the third ventricle with age, cIMT and RI of the MCA, kidney and spleen. In CNIs group the SN correlated positively with age and cIMT, while the third ventricle reproduced RTRs correlations. Rapamycin group showed a direct linear relationship between the third ventricle and age and RI of the MCA, kidney and spleen; SN showed no correlations.

CONCLUSION

RTRs on CNIs present a larger SN area than on rapamycin, probably due to the antiproliferative effect of rapamycin. This finding might be relevant when interpreting TCS in RTRs.

Metoclopramide and Levosulpiride Use and Subsequent Levodopa Prescription in the Korean Elderly: The Prescribing Cascade

The aim of this study was to investigate the prescribing cascade phenomenon of dopaminergic drugs such as levodopa in the management of gastroprokinetic drugs induced parkinsonism. Based on the Korea National Health Insurance Service (NHIS)-Senior Cohort Database, we analyzed patients aged ≥65 years, between 2009 and 2013, who obtained new prescriptions for levodopa through the NHIS during this period. Those who were prescribed levodopa from 2002 to 2008 were excluded, only patients who were prescribed metoclopramide and levosulpiride within 90 days of receiving the levodopa prescription were included. Those who did not receive levodopa were used as a control group for 1:3 age and sex matching. We assessed 1824 and 1197 levodopa cases for metoclopramide and levosulpiride use, respectively. The matched controls for each levodopa case were 5472 and 3591, respectively. We used conditional logistic regression to determine the odds ratio (OR) for initiation of levodopa therapy in patients using metoclopramide and levosulpiride, relative to nonusers, after adjusting for age, sex, and exposure to antipsychotic medication. Both metoclopramide (OR = 3.04; 95% confidence interval, CI, 2.46-3.77) and levosulpiride (OR = 3.32; 95% CI, 2.56-4.3) users were three times more likely to begin using medication containing levodopa, compared to nonusers. Metoclopramide and levosulpiride were frequently prescribed within 90 days of receiving a prescription for levodopa. Before prescribing levodopa, it should be considered whether the adverse event is actually a side effect caused by metoclopramide and levosulpiride.

Transcranial B-Mode Sonography in Movement Disorders

Applying a 2-4MHz probe at the temporal bone window transcranial B-mode sonography (TCS) enables the depiction of the brain parenchyma through the intact skull. Meanwhile it has been applied for the diagnosis and the differential diagnosis of movement disorders for decades. In the first part of this chapter, we summarize the technical requirements and describe the ultrasound method for optimal TCS examination. Imaging planes and the relevant structures are explained in detail. In the second part of the chapter, we focus on the role of substantia nigra hyperechogenicity for the diagnosis of Parkinson's disease (PD) and prodromal PD. In this part, we also mention the role of TCS in atypical and secondary Parkinsonian syndromes and other movement disorders. Summarizing all these information we explain how TCS can be helpful for the differential diagnosis of movement disorders. The current data show that TCS is an easily applicable and economic imaging method which can be used as an additional tool for the diagnosis of PD with a high sensitivity (>85%), specificity (>80%) and inter-rater reliability (>84%) as well as for the differential diagnosis of movement disorders. Lately, TCS has also been utilized in further areas such as the detection of individuals at risk for PD or the determination of electrode localization in patients with deep brain stimulation. An insufficient temporal bone window especially in the elderly and the necessity of an experienced investigator are limitations of this method.

Transcranial sonography in psychiatry as a potential tool in diagnosis and research

OBJECTIVES

During the last two decades transcranial sonography (TCS) of the brain parenchyma evolved from a pure research tool to a clinical relevant neuroimaging method especially in Parkinson's disease and related movement disorders. The aim of this systematic review is to update and summarise the published TCS findings in psychiatric disorders and critically address the question whether TCS may be a valuable tool for the diagnosis or differential diagnosis of psychiatric disorders similarly to the field of movement disorders.

METHODS

This paper provides detailed information about the perspectives and limitations of TCS, including guidelines for the scanning procedures, assessment of midbrain structures and discusses the potential causes of the ultrasound abnormalities in psychiatric disorders.

RESULTS

Changes in the echogenicity of subcortical brain structures were detected in different disorders, such as obsessive-compulsive disorder, autism spectrum disorder, schizophrenia, panic disorder, attention-deficit/hyperactivity (ADHD), bipolar disorder and depressive disorder. Although the physical properties of brain tissue underlying the echogenic features in TCS are largely unknown, no alternative technique provides the same insight into the specific central nervous structural characteristics.

CONCLUSIONS

Urgent research questions to further clarify the underlying pathophysiological and structural alterations are further outlined to bring this promising technique to the clinic.

Individualised short-term therapy for adolescents impaired by attention-deficit/hyperactivity disorder despite previous routine care treatment (ESCAadol)-Study protocol of a randomised controlled trial within the consortium ESCAlife

BACKGROUND

Despite the high persistence rate of attention-deficit/hyperactivity disorder (ADHD) throughout the lifespan, there is a considerable gap in knowledge regarding effective treatment strategies for adolescents with ADHD. This group in particular often shows substantial psychosocial impairment, low compliance and insufficient response to psychopharmacological interventions. Effective and feasible treatments should further consider the developmental shift in ADHD symptoms, comorbidity and psychosocial adversity as well as family dysfunction. Thus, individualised interventions for adolescent ADHD should comprise a multimodal treatment strategy. The randomised controlled ESCAadol study addresses the needs of this patient group and compares the outcome of short-term cognitive behavioural therapy with parent-based telephone-assisted self-help.

METHODS/DESIGN

In step 1, 160 adolescents aged 12 to 17 years with a diagnosis of ADHD will undergo a treatment as usual (TAU) observation phase of 1 month. In step 2, those still severely affected are randomised to the intervention group with an Individualised Modular Treatment Programme (IMTP) or a telephone-assisted self-help programme for parents (TASH) as an active control condition. The IMTP was specifically designed for the needs of adolescent ADHD. It comprises 10 sessions of individual cognitive behavioural therapy with the adolescents and/or the parents, for which participants choose three out of 10 available focus modules (e.g. organisational skills and planning, emotion regulation, problem solving and stress management, dysfunctional family communication). TASH combines a bibliotherapeutic component with 10 counselling sessions for the parents via telephone. Primary outcome is the change in ADHD symptoms in a clinician-rated diagnostic interview. Outcomes are assessed at inclusion into the study, after the TAU phase, after the intervention phase and after a further 12-week follow-up period. The primary statistical analysis will be by intention-to-treat, using linear regression models. Additionally, we will analyse psychometric and biological predictors and moderators of treatment response.

DISCUSSION

ESCAadol compares two short-term non-pharmacological interventions as cost-efficient and feasible treatment options for adolescent ADHD, addressing the specific needs and obstacles to treatment success in this group. We aim to contribute to personalised medicine for adolescent ADHD intended to be implemented in routine clinical care.

TRIAL REGISTRATION

German Clinical Trials Register (DRKS), Current Controlled Trial DRKS00008974, http://apps.who.int/trialsearch/Trial2.aspx?TrialID=DRKS00008974 ; http://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00008974 ; Registered on 28 December 2015.

Substantia Nigra Echogenicity Predicts Response to Drug Withdrawal in Suspected Drug-Induced Parkinsonism

Introduction

Response to drug withdrawal in patients with suspected drug-induced parkinsonism (DIP) is of prognostic and therapeutic importance, but cannot be predicted solely on clinical information. The aim of this study was to validate SN hyperechogenicity (SN+) assessed by transcranial sonography as a predictor of response to drug withdrawal in this group of patients.

Methods

Patients were diagnosed according to previously published criteria and prospectively included in the study. All patients were followed until complete recovery of parkinsonian symptoms or at least for 6 months after discontinuation of the offending drug and then diagnosed as DIP or parkinsonism following neuroleptic exposure (PFNE). Transcranial sonography (TCS) findings were compared with the clinical diagnosis.

Results

Sixty patients comprised the group for the final analysis. Sixteen patients were classified as PFNE and 44 as DIP. The area of SN echogenicity was significantly increased in the PFNE group (0.23 cm²; standard deviation [SD]: 0.04), compared to the DIP group (0.14 cm²; SD, 0.05; one-way analysis of variance; P < 0.001). Normal SN was significantly associated with complete recovery after withdrawal of the parkinsonism-inducing drug (P < 0.0005). Accuracy of SN+ to distinguish PFNE from DIP was: sensitivity 81.2%; specificity 84.1%; positive predictive value 47.4%; and negative predictive value 96.2%.

Conclusions

We believe that SN+ assessed with TCS is a valid prognostic marker in the setting of suspected DIP. It is a nonexpensive, feasible technique that can be implemented for proper counseling and guidance of treatment decisions.

Detection, Assessment, and Management of Schizophrenia in an Andean Population of South America: Parkinsonism Testing and Transcranial Ultrasound as Preventive Tools

Schizophrenia is a debilitating psychiatric illness that is among the world's top 10 causes of long-term disability, affecting people who are just entering the peak of social, economic, and intellectual productivity. Such functional loss is particularly relevant in indigenous communities, which rely on change in functional status (rather than on the presence of symptoms) to identify mental illness. Particularly among the indigenous communities of Latin America, the gap between mental health need and availability of resources to reduce the burden has been judged "a case of outrageous exclusion." For more than a decade, as part of the Investigation of Movement Abnormalities and Genetic of Schizophrenia study, the authors have been studying vulnerability markers (genetic, motor, imaging, and neuropsychological differences) for schizophrenia in a remote, indigenous population in rural northern Argentina. In this article, the authors discuss the implementation of a task-shifting paradigm resulting in more proficient identification and referral of individuals with untreated psychosis and a severalfold reduction in the duration of untreated psychosis, with very high retention rates (70%) and treatment adherence during a decade in a rural environment. The authors also propose to use transcranial ultrasound screening and testing for parkinsonism at illness onset before introduction of neuroleptics as potentially useful markers in determining illness severity, negative symptomatology, and tolerance to antipsychotic treatment/refractoriness.

Sex and laterality differences in parkinsonian impairment and transcranial ultrasound in never-treated schizophrenics and their first degree relatives in an Andean population

We tested the hypothesis that loss of substantia nigra neurons in subjects at risk of schizophrenia (1), as reflected by midbrain hyperechogenicity (2) and parkinsonian motor impairment (3), is asymmetric and influenced by sex. We evaluated 62 subjects with never-treated chronic schizophrenia, 80 of their adult, unaffected first degree relatives and 62 healthy controls (matched by sex and age to the cases), part of an Andean population of Northern Argentina. Parkinsonism was scored blindly using UPDRS-3 (Unified Parkinson's Disease Rating Scale) on videotaped exams by 2 independent raters. Transcranial ultrasound was performed by an expert sonographist blind to subject condition with a 2.5 MHz transducer through a temporal bone window. Quantification of echogenic area was carried out on saved images by a different evaluator. We found a significant difference in parkinsonian motor impairment between patients, their relatives as well as controls. All three groups showed worse parkinsonism on the left side than the right, corresponding with increased echogenicity on the right substantia nigra compared with the left. Females had significantly more right echogenicity than males, and patients and unaffected relatives were significantly more echogenic than controls on that side. On the left, only female patients had significant echogenicity. Our data supports the notion that unaffected relatives of schizophrenic subjects have increased parkinsonism and concomitant brainstem abnormalities which may represent a vulnerability to the disease. Both motor and brainstem abnormalities are asymmetric and influenced by sex.

Clinimetric evaluation of the Simpson-Angus Scale in older adults with schizophrenia

OBJECTIVE

Parkinsonism (or Parkinson's syndrome [PS]) remains common in patients exposed to antipsychotic drugs. One clinical tool used in its detection and follow-up, the Simpson-Angus Scale (SAS), has been under revision lately. We further examined the discriminative power of the SAS to detect PS and its efficacy as a measure of PS intensity in chronic schizophrenia.

METHODS

Fifty-six outpatients between 50 and 75 years of age, under stable antipsychotic drug therapy, provided consent to undergo an evaluation along the SAS and Unified Parkinson's Disease Rating Scale III motor subsection, split according to the presence or absence of PS defined in the UK Parkinson's Disease Society Brain Bank (UKPDSBB) criteria or Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria.

RESULTS

The identification rate for PS was 39.3% based on UKPDSBB criteria applied to the Unified Parkinson's Disease Rating Scale III, compared with 62.5% and 87.5% according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria and SAS cutoff value greater than 0.3, respectively. Median SAS scores for PS and PS-free participants were comparable. The SAS yielded high sensitivity (90.9%) but low specificity (17.7%). κ Values generally revealed only slight agreement between the group allocation provided by the SAS and the UKPDSBB criteria. Receiver operating characteristic curve for screening performance of the SAS provided poor prediction of subject status.

CONCLUSIONS

The SAS lacks specificity and constitutes an imperfect detection and measurement tool for PS in older adults. Raising the cutoff score would avoid inflation in PS identification. The scale is probably best used as a measure of change relative to baseline score following an intervention, but results should be interpreted with caution.

Do atypical antipsychotics really enhance smoking reduction more than typical ones?: the effects of antipsychotics on smoking reduction in patients with schizophrenia

Whether atypical antipsychotics (AAs) can enhance smoking reduction in schizophrenic patients remains controversial because of methodological limitations in existing studies. This study explored whether certain types of antipsychotics predict smoking reduction in schizophrenic patients. Three hundred eight smoking, predominantly male schizophrenic patients (271/308 [88.9%]) participated in an 8-week open-label study with antismoking medications (high-dose, low-dose nicotine transdermal patch and bupropion). Antipsychotics were classified into (1) typical antipsychotics (TAs) and (2) AAs, including multiacting receptor-targeted antipsychotics (clozapine, olanzapine, and quetiapine), serotonin-dopamine antagonists (risperidone), D2/D3 receptor antagonists (amisulpride), and partial dopamine receptor agonists (aripiprazole). A general linear model was used to explore whether types of antipsychotic predict changes in the number of cigarettes smoked per day (CPD) and the score of the Fagerstrom Test for Nicotine Dependence (FTND) while controlling for confounding factors. The type of antipsychotic (TAs or AAs) was not significantly associated with smoking cessation (n = 21; χ = 1.8; df = 4; P = 0.77). Regarding smoking reduction, the type of antipsychotic was significantly predictive of a change in the CPD (P = 0.027; partial eta square = 0.055) and FTND scores (P = 0.002; partial eta square = 0.073). The 95% confidence intervals of the estimated means of change in the CPD and FTND scores did not contain zero only among subjects on TAs or clozapine.These findings suggest that TAs and clozapine enhance smoking reduction compared with nonclozapine atypical antipsychotics in schizophrenic patients. The mechanisms underlying the effects of various antipsychotics on smoking reduction remain unclear and warrant future study.

First demonstration that brain CYP2D-mediated opiate metabolic activation alters analgesia in vivo

The response to centrally acting drugs is highly variable between individuals and does not always correlate with plasma drug levels. Drug-metabolizing CYP enzymes in the brain may contribute to this variability by affecting local drug and metabolite concentrations. CYP2D metabolizes codeine to the active morphine metabolite. We investigated the effect of inhibiting brain, and not liver, CYP2D activity on codeine-induced analgesia. Rats received intracerebroventricular injections of CYP2D inhibitors (20 μg propranolol or 40 μg propafenone) or vehicle controls. Compared to vehicle-pretreated rats, inhibitor-pretreated rats had: (a) lower analgesia in the tail-flick test (p<0.05) and lower areas under the analgesia-time curve (p<0.02) within the first hour after 30 mg/kg subcutaneous codeine, (b) lower morphine concentrations and morphine to codeine ratios in the brain (p<0.02 and p<0.05, respectively), but not in plasma (p>0.6 and p>0.7, respectively), tested at 30 min after 30 mg/kg subcutaneous codeine, and (c) lower morphine formation from codeine ex vivo by brain membranes (p<0.04), but not by liver microsomes (p>0.9). Analgesia trended toward a correlation with brain morphine concentrations (p=0.07) and correlated with brain morphine to codeine ratios (p<0.005), but not with plasma morphine concentrations (p>0.8) or plasma morphine to codeine ratios (p>0.8). Our findings suggest that brain CYP2D affects brain morphine levels after peripheral codeine administration, and may thereby alter codeine's therapeutic efficacy, side-effect profile and abuse liability. Brain CYPs are highly variable due to genetics, environmental factors and age, and may therefore contribute to interindividual variation in the response to centrally acting drugs.

High dosage of aripiprazole-induced dysphagia

BACKGROUND

Dysphagia as a main manifestation of extrapyramidal symptoms is an uncommon adverse effect of second-generation antipsychotics.

METHOD

We present a 54-year-old drug-naïve patient with schizophrenia, who developed dysphagia with aripiprazole 30 mg daily treatment.

RESULTS

This is the first case report on aripiprazole-induced dysphagia. We discuss the risk factors that led to dysphagia in this case.

CONCLUSION

Aripiprazole-induced dysphagia is rare, and it is important to be aware that it does occur with high-dosage treatment.

A tipping point in drug dosing in late-life schizophrenia

Minimally effective doses of antipsychotics are likely influenced by several clinical and demographic characteristics of patients, with age being one of the most important elements. In light of age-related physiologic changes as well as interindividual differences in pharmacokinetic and pharmacodynamic systems, individualized dosing with regard to age will be critically important for safer drug treatment for older patients with schizophrenia. In the present review, we propose the following cautious psychopharmacologic interventions for this population: 1) simple regimen (avoid polypharmacy), 2) be aware of the presence of patients who are very sensitive to drugs, 3) gradual dose titration, and 4) timely and thorough assessments of therapeutic and side effects. The age-related antipsychotic sensitivity highlights the importance of finding the lowest possible effective dose of antipsychotic drugs as patients with schizophrenia age to maximize therapeutic effects and minimize side effects.

[Transcranial sonography in diagnosis of movement disorders]

Conventional methods of neuroimaging, such as computed tomography and magnetic resonance imaging, are mostly useful in exclusion of movement disorders with secondary aetiology. Recently, the application of transcranial sonography has been introduced to the diagnosis of extrapyramidal diseases. This valuable technique, with proven usefulness in the field of cerebrovascular events, may reveal some brain parenchymal structures. In this review the most important findings of ultrasonographic abnormalities in the brain, particularly hyperechogenicity of substantia nigra in Parkinson disease, are presented.

Sensitivity to antipsychotic drugs in older adults

Antipsychotic medications are widely used to manage psychotic and behavioral disorders in older adults, including primary psychotic disorders such as schizophrenia, and psychosis and behavioral disturbances associated with dementia. These two broad diagnostic indications are associated with contrasting recommended treatment durations, with the former requiring indefinite treatment across the life span. Antipsychotic drug dosing for schizophrenia is based primarily on studies of younger patients and thus may not apply to older adults. It is critically important to address the effects of aging on antipsychotic dosing given the recent emergence of data that suggest a critical role for age-related sensitivity to these drugs. Antipsychotic drugs are not only associated with somatic and neurological adverse effects but also increased all-cause mortality and sudden cardiac death in this vulnerable population. This review focuses on the sensitivity of older adults to adverse effects from antipsychotic medications and the current pharmacokinetic and pharmacodynamic explanatory models of susceptibility. Implications of recent research findings for individualized pharmacotherapy are discussed.

Dosing of antipsychotics in schizophrenia across the life-spectrum

Age effects on dosing of antipsychotics in schizophrenia and mechanisms underlying those effects have not been well understood. The objective of this article is to review the literature regarding effects of age on antipsychotic dosing in schizophrenia and potential mechanisms underlying the age-related antipsychotic sensitivity. According to prescription surveys, age appears to have biphasic effects on prescribed antipsychotic dose. The dose increased with age through the third decade, subsequently plateaued, and decreased after the fifth decade. The first half of this inverted U-shaped relationship may be attributable to a deterioration process in the early phase of schizophrenia and the contribution of 'tachyphylaxis' of antipsychotics on the dopaminergic system. The following age-related decline in prescribed dose is likely associated with physiological aging. Recent data suggest that this increased antipsychotic sensitivity with age comes from age-related functional decline in the dopaminergic system, including endogenous dopamine level and dopamine receptor density. Although the evidence on potential mechanisms underlying age effects on antipsychotic dosing is still limited, alterations in the dopaminergic system due to aging and chronic exposure to this drug may contribute to the inverted U-shaped relationship between dose and age. This age-related antipsychotic sensitivity highlights the importance of finding the lowest possible effective dose of antipsychotic drugs as patients age to enhance therapeutic effects as well as minimize their side effects.

Lack of association between antipsychotic-induced Parkinsonism or its subsymptoms and rs4606 SNP of RGS2 gene in African-Caribbeans and the possible role of the medication: the Curacao extrapyramidal syndromes study X

Recent studies demonstrate an association between antipsychotic-induced parkinsonism (AIP) and rs4606 SNP of RGS2 gene in Jewish and African-Americans. The current study investigates the association between rs4606 and AIP or its subsymptoms (rest tremor, rigidity, and bradykinesia) in 112 psychiatric inpatients of African-Caribbean origin. Presence of AIP, rigidity, bradykinesia, and tremor was measured by the UPDRS. We applied chi(2) (or Fisher Exact) and logistic regression analyses in several models including rs4606, age, gender, dose of antipsychotics, and anticholinergics, and two other putatively functional SNPs in DRD2 (-141CIns/Del) and HTR2C (Cys23Ser) genes. In contrast to recent literature, we find no evidence for an association between rs4606 and AIP or any of its subsymptoms. We hypothesize that the observed lack of association is due probably to differences in serotonin 2A-receptor affinities of the antipsychotics utilized (in contrast to the other published studies, the majority of our patients utilized typical antipsychotics).

Pharmacogenetics of parkinsonism, rigidity, rest tremor, and bradykinesia in African-Caribbean inpatients: differences in association with dopamine and serotonin receptors

We studied the association between polymorphisms of genes coding for dopamine D(2) (DRD2), dopamine D(3) (DRD3), serotonin 2(a) (HTR2A), and serotonin 2(c) (HTR2C) receptors and Antipsychotic-Induced Parkinsonism (AIP), rigidity, bradykinesia, and rest-tremor in African-Caribbeans treated with antipsychotics. Polymorphisms of DRD2 (-141CIns/Del, TaqIA, 957C > T), DRD3 (Ser9Gly), HTR2A (-1438A > G, 102T > C, His452Tyr), and HTR2C (-759C > T, Cys23Ser) genes were determined according to standard protocols. The Unified Parkinson Disease Rating Scale was used for the measurement of AIP, rigidity, bradykinesia, and rest-tremor. Chi-squared or Fisher's exact tests were applied for the association analyses. The t-test was applied for continuous data. Ninety nine males and 27 females met the inclusion criteria (Schizophr Res 1996, 19:195). In males, but not in females, there were significant associations between -141CDel-allele carriership (DRD2) and rigidity (Fisher's Exact Test: P = 0.021) and between 23Ser-allele carriership (HTR2C) and bradykinesia (P = 0.026, chi(2) = 5.0) or AIP (P = 0.008, chi(2) = 7.1). Rest-tremor was not associated with any of the polymorphisms studied. Analyses of the age, chlorpromazine equivalents, benztropine equivalents, the number of patients using anticholinergic medication, and the utilization patterns of the antipsychotic medication did not show statistically significant differences between patients with and without AIP, rigidity, bradykinesia, rest-tremor. Conducting the analysis without gender stratification did not affect our findings considerably, except for the association between bradykinesia and 23Ser-allele which failed to reach statistical significance in the total sample (P = 0.0646, chi(2) = 3.41). Since AIPs subsymptoms (rigidity, bradykinesia, and rest-tremor) may differ pharmacogenetically, our data strongly support symptom-specific analysis of AIP. However, further research is warranted to confirm our findings.

Drug-induced parkinsonism

Drug-induced parkinsonism (DIP) is the second cause of akinetic rigid syndrome in the Western world and its prevalence is increasing and approaching that of idiopathic Parkinson's disease due to the ageing of the population and to the rising of polypharmacotherapy. DIP was initially reported as a complication of neuroleptics in psychiatric patients, but it has also been described with a great diversity of compounds such as antiemetics, drugs used for the treatment of vertigo, antidepressants, calcium channel antagonists, antiarrythmics, antiepileptics, cholinomimetics and other drugs. Although traditionally considered reversible, DIP may persist after drug withdrawal. At least 10% of patients with DIP develop persistent and progressive parkinsonism in spite of the discontinuation of the causative drug. Irreversible or progressive DIP has been considered as an indication of presymptomatic parkinsonian deficit, unmasked but not caused by the offending drug, but it could be explained by persistent toxicity of the responsible pharmacological agents on the nigrostriatal dopamine pathway. The best treatment of DIP is prevention, including the avoidance of prescription of causative drugs whenever it is not strictly necessary. In patients who require potentially risky medication, it is necessary to perform adequate monitoring for early parkinsonian deficits and early discontinuation if these deficits appear. Atypical neuroleptics are associated with lower risk than first generation antipsychotic drugs. Special precautions are needed in elderly subjects, in patients treated with multiple drugs for prolonged periods of time and in those with familial risk factors including familial parkinsonism or tremor, or in those with genetic variants of genes involved in idiopathic Parkinson's disease.

Does smoking reduce akathisia? Testing a narrow version of the self-medication hypothesis

BACKGROUND

The self-medication hypothesis proposes that schizophrenia patients smoke to decrease their schizophrenia symptoms or antipsychotic side effects, but they usually start smoking before their illness and heavy smoking is not consistently associated with fewer symptoms or side effects. A narrow version of the self-medication hypothesis, heavy smoking reduces akathisia, is explored.

METHOD

The sample included 250 outpatients with DSM-IV schizophrenia assessed with the Positive and Negative Syndrome Scale (PANSS) and the Barnes Akathisia Scale. Prevalences were 69% (173/250) for smoking, 39% (98/250) for heavy smoking (> or =30 cigarettes/day), 7% (17/250) for akathisia (Barnes Global score>1), 14% (35/250) for a broader akathisia definition (Barnes Global score>0) and 20% for excited symptoms (>1 on the PANSS factor score).

RESULTS

Heavy smoking was not associated with akathisia (41% of patients with akathisia were heavy smokers versus 39% of patients without akathisia; chi2=0.3, df=1, p=0.86), even after correcting for confounding factors and/or using a broader akathisia definition. Heavy smoking was associated with excited schizophrenia symptoms (possibly reflecting agitation). Particularly in patients taking lower doses of typical antipsychotics, excited symptoms, with or without akathisia, were strongly associated with heavy smoking and appear to interact with patients' reports of smoking's calming effect as the main reason for smoking.

CONCLUSION

The self-medication hypothesis does not explain increased smoking and heavy smoking in schizophrenia. Moreover, heavy smoking may be associated with more disturbed brain homeostatic mechanisms. Prospective studies need to explore whether temporary increases in cigarette smoking may be associated with periods of higher agitation, with or without akathisia.