Comparison of objectively measured motor behavior with ratings of the motor behavior domain of the Bern Psychopathology Scale (BPS) in schizophrenia.

Motor symptoms in schizophrenia occur frequently and are relevant to diagnosis and antipsychotic therapy. To date motor symptoms are difficult to assess and their pathobiology is a widely unresolved issue. The Bern Psychopathology Scale for the assessment of system-specific psychotic symptoms (BPS) was designed to identify homogenous patient groups by focusing on three domains: language, affectivity and motor behavior. The present study aimed to validate the motor behavior domain of the BPS using wrist actigraphy. In total, 106 patients were rated with the BPS and underwent 24 h continuous actigraphy recording. The ratings of the global severity of the motor behavior domain (GSM) as well as the quantitative and the subjective items of the motor behavior domain of the BPS were significantly associated with actigraphic variables. In contrast, the qualitative items of the motor domain failed to show an association with actigraphy. Likewise, scores of the language and the affectivity domains were not related to actigraphic measures. In conclusion, we provided substantial external validity for global, quantitative and subjective ratings of the BPS motor behavior domain. Thus, the BPS is suitable to assess the dimension of quantitative motor behavior in the schizophrenia spectrum.

Measuring motor activity in major depression: the association between the Hamilton Depression Rating Scale and actigraphy.

Despite the use of actigraphy in depression research, the association of depression ratings and quantitative motor activity remains controversial. In addition, the impact of recurring episodes on motor activity is uncertain. In 76 medicated inpatients with major depression (27 with a first episode, 49 with recurrent episodes), continuous wrist actigraphy for 24h and scores on the Hamilton Depression Rating Scale (HAMD) were obtained. In addition, 10 subjects of the sample wore the actigraph over a period of 5 days, in order to assess the reliability of a 1-day measurement. Activity levels were stable over 5 consecutive days. Actigraphic parameters did not differ between patients with a first or a recurrent episode, and quantitative motor activity failed to correlate with the HAMD total score. However, of the motor-related single items of the HAMD, the item activities was associated with motor activity parameters, while the items agitation and retardation were not. Actigraphy is consistent with clinical observation for the item activities. Expert raters may not correctly rate the motor aspects of retardation and agitation in major depression.

Higher motor activity in schizophrenia patients treated with olanzapine versus risperidone.

There are indications that atypical antipsychotics differ in the probability of causing motor retardation. Whereas olanzapine seems to exert sedation, risperidone might slow patients because of parkinsonism or increased negative symptoms. Objective data on gross motor activity are not available. We present actigraphic data of 16 schizophrenia patients treated with olanzapine (mean dose, 21.1 mg/d) and 23 with risperidone (mean dose, 4.7 mg/d) to investigate possible differences in their effects on motor activity. Participants wore actigraphs continuously for 24 hours at the nondominant arm. Groups did not differ in age, Positive and Negative Syndrome Scale scores, duration of illness, and number of episodes. Patients treated with olanzapine had higher activity levels than those treated with risperidone (P = 0.024); this effect was robust and also present after covarying for chlorpromazine equivalents and Positive and Negative Syndrome Scale scores. Movement index (proportion of active episodes) and the average duration of immobility, however, failed to show any difference between groups. The results indicate that patients on olanzapine are more active during the day than patients on risperidone. It remains unclear whether this difference is due to subthreshold parkinsonism with risperidone or stronger beneficial effects of olanzapine on psychomotor slowing. Because the average duration of immobility remained unaffected, sedation is not likely to be the cause for the observed differences.

The Bern psychopathology scale for the assessment of system-specific psychotic symptoms.

The translation from psychiatric core symptoms to brain functions and vice versa is a largely unresolved issue. In particular, the search for disorders of single brain regions explaining classical symptoms has not yielded the expected results. Based on the assumption that the psychopathology of psychosis is related to a functional imbalance of higher-order brain systems, the authors focused on three specific candidate brain circuitries, namely the language, and limbic and motor systems. These domains are of particular interest for understanding the disastrous communication breakdown during psychotic disorders. Core symptoms of psychosis were mapped on these domains by shaping their definitions in order to match the related brain functions. The resulting psychopathological assessment scale was tested for interrater reliability and internal consistency in a group of 168 psychotic patients. The items of the scale were reliable and a principal component analysis (PCA) was best explained by a solution resembling the three candidate systems. Based on the results, the scale was optimized as an instrument to identify patient subgroups characterized by a prevailing dysfunction of one or more of these systems. In conclusion, the scale is apt to distinguish symptom domains related to the activity of defined brain systems. PCA showed a certain degree of independence of the system-specific symptom clusters within the patient group, indicating relative subgroups of psychosis. The scale is understood as a research instrument to investigate psychoses based on a system-oriented approach. Possible immediate advantages in the clinical application of the understanding of psychoses related to system-specific symptom domains are also discussed.

Objectively measured motor activity in schizophrenia challenges the validity of expert ratings.

Motor symptoms are frequent in schizophrenia and relevant to diagnosis. They are usually assessed by clinical observation and ratings based on psychometric scales. However, investigations with quantitative measurements are rare. To understand the relationship between the objective parameters of a quantitative motor activity measurement and the items related to motor symptoms of the Positive and Negative Syndrome Scale (PANSS), 55 schizophrenia patients were studied with 24-h continuous wrist actigraphy. Activity level, movement index, and mean duration of uninterrupted immobility periods were analyzed for wakeful periods. Actigraphic parameters were strongly inter-correlated. High PANSS negative syndrome subscale scores predicted low activity levels. Single PANSS items, such as suspiciousness, hallucinatory behavior, and emotional withdrawal, contributed largely to the variance in activity level and movement index. Age, gender, medication, and duration of illness had no significant impact on the actigraphic parameters. Interestingly, correlations between the specific motor symptoms of the PANSS and the actigraphic parameters were only found as a non-significant trend. We conclude that the objectively measured quantity of movement is related to the clinically assessed negative syndrome in schizophrenia. In contrast, PANSS items related to psychomotor behavior imprecisely reflect real quantitative motor activity.

Quantitative motor activity differentiates schizophrenia subtypes.

BACKGROUND: Motor symptoms are frequent in schizophrenia and relevant to the diagnosis of subtypes. However, the assessment has been limited to observations recorded in scales and experimental designs. The aim of this study was to use wrist actigraphy to obtain motor activity data in 3 schizophrenia subtypes. METHODS: In total, 60 patients with schizophrenia (35 paranoid, 12 catatonic, 13 disorganized) were investigated using continuous wrist actigraphy over 24 h in an inpatient setting on average 38 days after admission. Data of the wakeful hours of the day were analyzed. RESULTS: The activity level was predicted by schizophrenia subtype and by the type of antipsychotic medication. The movement index and mean duration of uninterrupted immobility were found to be predicted only by the schizophrenia subtype. Age, gender, duration of illness and chlorpromazine equivalents did not contribute to the variance of the activity data. A MANOVA demonstrated the significant differences in the 3 parameters between schizophrenia subtypes (p = 0.001). Patients with catatonic schizophrenia had lower activity levels, a lower movement index and a longer duration of immobility than those with paranoid schizophrenia. CONCLUSIONS: Schizophrenia subtypes can be differentiated using objective measures of quantitative motor activity. The increased duration of immobility appears to be the special feature of catatonic schizophrenia.

Increased motor activity in cycloid psychosis compared to schizophrenia.

Although cycloid psychoses share psychopathological features with schizophrenia, their course and outcome are comparable to those seen in bipolar affective disorder. The diagnostic category is of interest because it has been demonstrated that cycloid psychoses can be diagnosed reliably and distinguished from other psychoses based on treatment response and neurophysiology. Despite this, only few studies have investigated the neurobiological differences between cycloid psychoses and schizophrenia, and although hyper- and hypoactivity have been observed in patients with cycloid psychoses, no studies have investigated motor activity in this group to date. Therefore, we aimed to quantify motor activity during the waking hours of the day as assessed by wrist actigraphy in 16 patients with cycloid psychosis and 16 patients with paranoid schizophrenia. All patients were matched for gender and age, and wrist actigraphic assessment took place during acute episodes. The level of activity and proportion of active vs. inactive periods during waking hours were significantly higher in patients with cycloid psychosis. The results of the present study are interpreted in light of a previously reported general arousal in cycloid psychoses that is expressed in motor activity. Our data support the concept of cycloid psychoses as a syndrome with distinct symptomatology and pathophysiology.