The Prevalence of Neuroleptic Drug-Induced Tardive Movement Subsyndromes among Schizophrenic and Schizoaffective Patients Residing in the Southern Region of Israel

Article excerpt

Abstract: The aim of the current study was to assess the prevalence of tardive movement disorders (TMD) among a group of institutionalized schizophrenic and schizoaffective patients in southern region of Israel. Chronic schizophrenic and schizoaffective inpatients of a psychiatric hospital and its affiliated hostels were screened for the presence of TMD subsyndromes. Twenty percent (107 patients) of 523 patients with schizophrenia and schizoaffective disorder exhibited TMD. Of those with TMD, 36% had only one subsyndrome, whereas 64% had a combination of several TMD subsyndromes. With regard to patients with TMD, the most frequent TMD subsyndrome was tardive tremor (TT). TT appeared more often in males compared to females and at a younger age (44.3±8 vs. 54.3±11 years, P<0.04). TD appearing in combination with other TMD subsyndromes was significantly more prevalent among females than in males (57% vs. 35%; P<0.02). TMD generally appears in a combined fashion. Further prospective studies from different geographical areas are recommended.

Introduction

Psychotropics remain the therapeutic mainstay for the treatment of many psychiatric disturbances, particularly acute and chronic schizophrenia and other psychotic states. Psychotropic drug-induced movement disorders represent a major cause of morbidity in the management of these conditions. The prevalence of tardive dyskinesia (TD) has been extensively investigated, with rates reported to range from 3% to as high as 70% among subjects treated with these drugs (1). Although the newer generation of antipsychotic medications have a significantly reduced potential for causing acute and tardive neurolepticinduced movement disorders including TD (2-4), they may nevertheless induce movement disorders (5-9). Also, the first generation neuroleptics are still used extensively in clinical practice.

TD was first described in the 1950s. At that time it was considered to be a relatively rare syndrome. The term "tardive dyskinesia" was considered to be a single condition, consisting of a persistent movement disorder occurring as a complication of the long-term administration of dopamine blocking medications. More recently, TD and TD-like syndromes have been reported to occur as a result of the administration of other drugs, such as selective serotonin reuptake inhibitors (SSRI), atypical antipsychotics, antiepileptics, and lithium (10-17). Also, TD is now considered to represent a wide range of delayed-onset abnormal involuntary movements and motor disturbances the pathophysiology of which is related not only to dopamine receptor blocking agents (18). Hence, a more appropriate term would be drug-induced tardive subsyndromes or subtypes (1, 19-25), or psychotropic drug-induced tardive movement disorders (TMD). It is suggested that there are a number of variants of TMD and several researchers (1, 19-25) have proposed distinguishing between classical TD (orobuccofaciolingual and/or peripheral syndrome) and other psychotropic drug induced tardive subsyndromes, such as tardive akathisia (TA), tardive dystonia (TDt), tardive parkinsonism (TP), tardive tremor (TT), and tardive tics (TTc). Such a classification is based on data suggesting a differential profile of risk factors, clinical phenomenology, epidemiology, and treatment response for the various forms of TMD (1, 20, 23, 24). Of note is that the term "tardive tremor" is controversial. Some researchers suggest that tardive tremor is a form of "tardive parkinsonism" (26), whereas we conform with the opinion differentiating "tardive tremor" from other tardive movement disorders (18, 23, 25, 27).

In order to further our understanding of these TMD variants it is important to determine the prevalence of these syndromes in different geographical areas. The use of appropriate assessment instruments applied by experienced psychiatrists or neurologists are useful in evaluating these TMD variants. The aim of this study was to assess and map the patients and the prevalence of the different psychotropic-induced TMD subsyndromes - rather than its differential relationship with psychotropic treatment - among schizophrenic and schizoaffective inpatients of a psychiatric hospital and its affiliated hostels, serving a population of approximately 700,000 inhabitants in the southern region of Israel. …