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.
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.
Subjects with chronic schizophrenia and schizoaffective disorders (according to DSM-IV criteria) (28) were included in the study. All patients were of Caucasian origin. Inclusion criteria consisted of the following: a) male or female gender, older than 18 years; b) neuroleptic induced akathisia, tremor, tic, dystonia and parkinsonism diagnosed according to DSM-IV-TR research criteria for these acute disorders, with delayed appearance, and duration of at least a year; c) a diagnosis of TD (according to DSM-IV-TR research criteria ) or that of other variants of TMD was confirmed by three specialized psychiatrists very experienced in the diagnosis and treatment of movement disorders. (Tardive parkinsonism has been classified in this manuscript into proper TP [posture, gait, postural stability, rigidity and bradykinesia] and tardive tremor [resting tremor] without any other signs of parkinsonism); d) signs and symptoms of TMD developed either during exposure to a psychotropic medication, or within 4 weeks of withdrawal from oral neuroleptics or within 8 weeks of withdrawal from a depot form (28); e) exposure to psychotropic medication for at least 3 months prior to the appearance of TMD signs and symptoms; f) each of the psychotropic drug-induced movement subsyndromes should be at least of moderate severity, as measured by the clinical global impression of severity of the Extrapyramidal Symptom Rating Scale (ESRS) (29) for each of these subsyndromes (see below); g) patients were either hospitalized in chronic wards of the psychiatric hospital or were residing in a hostel supervised by the staff of this hospital. The last requirement assured an adequate documentation of history of psychiatric, medical, neurological and medication status.
Exclusion criteria included: a) patients demonstrating any acute movement disorders which appeared shortly after beginning psychotropic treatment; b) patients with neurological diseases including Parkinson's disease and Huntington's chorea, or those with a family history of hereditary movement disorders; c) patients with a history of substance or alcohol abuse.
This study was performed as a mapping process of all the TMD patients in the southern region of Israel. It was an initial and mandatory introductive part of two other clinical trials suggested as a treatment of tardive disturbances.
The study was approved by the institutional review board (IRB) and informed consent for participation was obtained from all subjects.
Three trained raters (VL, IL and AK) examined all psychiatric patients in the Beersheba Mental Health Center and its affiliated hostels over a period of 6 months (from July 1, 2003 to December 31, 2003). Schizophrenic and schizoaffective patients meeting the inclusion criteria and exhibiting movement disorders were carefully examined by the raters, and were rated using the Extrapyramidal Symptom Rating Scale (ESRS) (29). This scale consists of eight subscales including subjective and objective findings, and enables the assessment of the severity of tardive forms of parkinsonism, tremor, akathisia, dystonia and dyskinesia. Additionally, tardive akathisia and tardive tremor were rated by the use of the Barnes Akathisia Rating Scale (BARS) (30) and Simpson Angus Scale (SAS) (31) respectively. The interrater reliability of ESRS, BARS and SAS rating scales was: ?=0.94, =0.89, and =0.92 respectively. The tardive nature of the movement dis- orders was also determined by taking into consideration the discontinuation or dose reduction (according medical records) of the psychotropic drug for a period of at least 2 weeks leading to an aggravation of the movement disorder/s, and a subsequent improvement after restarting treatment. Following psychiatric and neurological assessments, evaluations were performed for the severity of TMD, and demographic data were obtained, including gender, diagnosis, age at the onset of illness, age at first hospitalization and the duration of illness. Detailed treatment histories were also determined, with an emphasis on the duration of treatment with neuroleptics and other psychotropic drugs. The data regarding the illness and treatment history were obtained from the medical records reported by treating physicians for each patient. Furthermore, all subjects were interviewed by one of the researchers.
Neuroleptic doses at the time of the patients' evaluation were converted to chlorpromazine equivalents (32). At the time of evaluation, 64% of the patients were treated with typical neuroleptics (mean±SD chlorpromazine equivalent dose: 533198 mg/day, with a range of 100-900 mg/day). Thirty-six percent of patients were treated with a variety of atypical antipsychotics (amisulpride mean 769±253 mg/day, range 600-1000 mg/day; clozapine mean 296.0±125.8mg/day, range 100-500 mg/day; olanzapine mean 19.0±8.4 mg/day, range 10-30 mg/day; risperidone mean 4.6±2.6 mg/day, range 37 mg/day; or ziprasidone mean 126±37 mg/day, range 80-180 mg/day). Thirty-eight patients (36%) received different mood stabilizers (lithium mean 1194±523 mg/day, range 750-1800 mg/day; carbamazepine mean 1347±417 mg/day, range 9001800 mg/day, or valproate mean 1259±493 mg/day, range 800-2000 mg/day) in combination with antipsychotic agents. Seventy-seven patients (72%) were concurrently being treated with anticholinergic-antiparkinsonian agents, including trihexyphenidyl (mean 4.2±1.7 mg/day, range 2-6 mg/day, or biperiden mean 4.0±1.9 mg/day, range 26 mg/day).
All statistical analyses were done with SPSS software, version 11 (Chicago, 111., U.S.A.). Differences between groups were examined with independent sample two-tailed f-tests for continuous variables and ?2 tests for categorical measures. Significance was determined at the 5% level. Statistical analysis was performed only for subgroups including more than 15 subjects.
A total of 523 patients with schizophrenia and schizoaffective disorder were screened. About twothirds (66%; 344 patients) of our sample had no psychotropic drug-induced movement side effects. Thirty- four percent (179 patients) had some type of psychotropic drug-induced movement disorder (acute or tardive). Of these, 107 patients (representing 20% of the total group screened) exhibited only tardive with no associated acute movement disorders, and this comprised our study group.
The study group included 63 males and 44 females, and mean age was 49±12 years. The patients' characteristics are presented in Table 1 .
Table 2 demonstrates the distribution of the various TMD subsyndromes (alone or in combination) according to age and gender.
Thirty-six percent of TMD patients had only one TMD subsyndrome. The most frequent subsyndrome was TT, appearing alone or in combination with other TMD subsyndromes in 22% and 44% of TMD patients respectively. TT appeared significantly more frequently among male patients (20 of 63 patients; 32%) than females (4 of 44 patients; 9%; %2=7.64; df=l, P<0.006), and the males were younger than the corresponding female group (mean age ±SD: 44.3±8 years vs. 54.3±11 years respectively; T=2.12; df=22, P<0.04). The more common combinations of subsyndromes were TT+TD (26%) and TT+TP (10%). A significantly greater percentage of females suffered from the TT and TD combination compared to males (12 of 63 male patients [19%] vs. 16 of 44 female patients [36%]; ?2=4.02, df=l, P<0.05) and these females were significantly older than the corresponding males (mean age ± SD: 44.2+14 years for males, 53.9+11 years for females; T=2.02; df=26, P=0.05). The combination of TT and TP was observed more frequently among males than females, but the difference was not statistically significant (8 out of 63 patients [13%] vs. 3 out of 44 patients [7%] respectively) (see Table 2).
TD alone or in combination was observed in 14.0% and 44% of patients with TMD subsyndromes respectively. The percentage of males suffering from TD alone did not differ significantly from that of females (7 of 63 patients [11%] vs. 8 of 44 patients [18%], respectively) and no significant age difference was noted between males and females (mean age ±SD of males 41.7±16 years, females 54.3±11 years), however TD in combination with other TMD subsyndromes was observed significantly more frequently among males than females (22 of 63 male patients [35%] vs. 25 of 44 female patients [57%]; ?2=5.04; df=l, P<0.02). Again no significant age difference was found between males and females in this subgroup (mean age +SD of males 49.9 +14 years, females 54.5±9 years). Among all patients with TD, the orobuccofaciolingual variant (classic TD) was observed in 34% of patients; classical TD in addition to choreoathetoid movements in the upper extremities in 21%; classical TD in addition to choreoathetoid movements in both upper and lower extremities in 18% (Table 3).
We have described the prevalence of drug-induced tardive movement disorders in a group of chronic schizophrenic and schizoaffective patients receiving psychotropic treatment. Our patients were mainly middle-aged, and all had received typical neuroleptics previously, with treatment subsequently changed either to atypical antipsychotics alone, or to a combination of typical and/or atypical antipsychotics, either due to a lack of an adequate clinical response or to the presence of side effects. Such a therapeutic strategy made it practically too complex to differentiate between the effect of typical versus atypical antipsychotics on the development of TMD. A subgroup analysis based on the type of neuroleptic medication administered was thus not performed.
Although tardive dyskinesia and its prevalence has been studied extensively, only a small number of studies has considered other subtypes or subsyndromes of tardive drug-induced movement disorders (1, 15, 19, 23, 26, 33-37). Moreover, it is sometimes difficult to determine whether authors reporting findings concerning TD had also included patients suffering from other psychotropic induced tardive subsyndromes.
Only eight publications have reported the prevalence of TMD subsyndromes (22, 34, 35, 38-42). All available data regarding the prevalence of the TMD, the nature of the sample and relevant demographic data in these studies are presented in Tables 4a and 4b. Among these, only the studies by Fahn (38) and Lauterbach et al. (22) reported the relative frequency of psychotropic induced tardive - not including acute - subsyndromes. Among 33 screened patients with classical TD, TA and TTc, Fahn (38) found that 30% of patients had classic TD, 67% had a combination of classic TD and TA and 3% had a combination of TTc and TA. Lauterbach and colleagues studied patients with definite TD, reporting the presence of TP (which is equivalent to combined TP and TT according to our definition) in 90% of these patients, TDt in 25% and TA in 10% (22). The findings of our study demonstrate that 62 patients (58% of the sample) had TD alone or in combination with other subtypes of TMD. At first glance this seems lower than the 97% reported by Fahn, although this author did not include TP or TDt among his subjects. Of the 62 patients in our study demonstrating TD and its combinations, TP along with TT was seen in 63%, TDt in 0%, and TA in 10%. Thus, if our findings are regrouped according to Lauterbach et al. the prevalence of TP in the presence of TD was lower, and TDt was not found at all among our patients. A similar prevalence of TA in the presence of TD was found in both studies (about 10%). It should be noted that, like Lauterbach et al. (22), we found that the majority of TD patients also exhibit TP and/or TT, according to our definitions, and this is in contrast to Fahn (38) who reported that the majority of TD patients also exhibited TA. However, both Fahn and Lauterbach et al. did not include the whole spectrum of TMD variants as done in our study. Our data demonstrated that TT is a widespread movement disturbance among our study patients. With regard to the relative frequency of TMD combinations, several authors have noted that tardive subsyndromes usually appear in a combined fashion of two or more forms (33, 38, 41, 42). In our sample, the percentage of those patients with TMD who had combinations of different subtypes was 58%.
Another subject of importance is the relationship between TMD and age or gender. Earlier studies suggested that classic TD is more likely to appear in elderly women. In contrast, recent studies have not confirmed that female gender is a risk factor for TMD (43), suggesting that some TMD subsyndromes may differ from classic TD with regard to gender. We found that the TT subsyndrome induced by psychotropic medications appears mainly among young and middle-aged males, whereas TD seems to be more frequent among middle-aged and elderly females, although such a tendency was not statistically significant in this study. The same non-significant tendency for parkinsonism and TD was reported by van Harten et al. (41).
Evidently, an assessment of the prevalence of psychotropic drug-induced movement disorders, even in studies relating specifically to non-acute TMD subsyndromes, is rather complex. This is due to the heterogeneity of the studied samples and to differences in defining the TMD variants or subsyndromes. These reservations should be taken into account when considering the relatively low prevalence of TD (ranging from 7.6% to 17.0%) reported in Chinese, Japanese and other Asian populations (40, 44, 45).
Another example stressing the influence of ethnic origin on the prevalence of TMD was the study by van Harten and colleagues (41). These authors studied all psychiatric inpatients in the Netherlands Antilles and examined both tardive and acute forms of psychotropic induced movement disorders (Table 4). The prevalence of tardive dystonia and tardive dyskinesia reported in this mainly black African sample was rather high compared to other studies. The authors suggested that the black population may be more prone to develop tardive dystonia (41). Gureje (34) found the prevalence of TD among Nigerian psychiatric patients to be 27% (Table 4). It is not clear if TP or TT also existed in these patients. In this regard, the influence of race on TD has been particularly studied by Glazer et al. (46), who found that being Negroid almost doubles the incidence of TD. However, Sramek et al. (47) reported no difference between Negroid and Caucasian patients in the prevalence of TD.
Another issue regarding TD relates to parts of the body (peripheral or orofacial) included in this variant of TMD. In this regard Muscettola et al. (35) reported the distribution of EPS with TD, demonstrating that tremor and akathisia were more frequent in patients exhibiting peripheral TD than in patients demonstrating orofacial TD. These authors speculated that perhaps TD, tremor and akathisia may share a common pathophysiology. According to Lauterbach et al. (22), 97% of subjects had orobuccofaciolingual TD, whereas 67% had upper extremity TD and 47% had lower extremity TD. In many of their cases the different types of TD occurred concomitantly. Most patients suffering from orobuccofaciolingual TD also had TP (TP according to Lauterbach et al. also includes TT). In our study about three-quarters of the patients with TD had orobuccofaciolingual type alone or in combination with peripheral TD and the majority of them had TT and TP (Table 3). These data may suggest that TT and TP do not necessarily characterize the peripheral type of TD.
Our study has a number of limitations. First, we assessed only institutionalized and hostel dwelling schizophrenic and schizoaffective patients, but not those in an outpatient setting. Secondly, the design used in this study made it too complex to determine the effect of different neuroleptic drugs on the prevalence of TMD. Also, although the recruited total sample was rather large, the number of patients identified in certain TMD subsyndrome groups was relatively small, thus our results should be viewed with caution. Further prospective studies are in need to clarify these findings.
Finally, as mentioned previously, the lack of a uniform approach in the literature to the definitions of the TMD variants or subsyndromes makes it difficult to compare the various studies, and a diagnostic consensus should be sought. Until then, we suggest that future research should focus on TMD - excluding acute forms of psychotropic induced movement disorders - and that the unique classification for the assessment of movement disorders suggested by Chouinard (37) should be studied for its utility. This will enable a more valid comparison as to the prevalence of TMD variants in different population groups, subsequently providing new insights into the psychotropic induced tardive movement disorders.
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Vladimir Lerner, MD, PhD, Igor Libov, MD, Alexander Kaptsan, MD, Chanoch Miodownik, MD, Tzvi Dwolatzky, MD, and Joseph Levine, MD
Division of Psychiatry, Ministry of Health Mental Health Center, and Faculty of Health Sciences, Ben-Gurion University of the Negev, Beersheba, Israel
Address for Correspondence: Prof. Joseph Levine, Mental Health Center, POB 4600, Beersheba 84170, Israel.