Approximately half of adults with schizophrenia suffer from motor abnormalities that may impair their ability to work and decrease their quality of life, wrote Niluja Nadesalingam, MD, of the University of Bern, Switzerland, and colleagues. “Although previous reports show strong associations between single movement abnormalities and global as well as social functioning, we still struggle to understand the contribution of various motor domains,” they said.
The impact of these abnormalities on social and global functioning and on functional capacity remains unclear, but the researchers proposed that motor abnormalities would be associated with worse functional outcomes in schizophrenia patients.
In a study published in, the researchers identified patients with diagnosed schizophrenia spectrum disorders who were treated on an inpatient or outpatient basis at a single center. They collected data on five motor abnormalities: parkinsonism, catatonia, dyskinesia, neurological soft signs (NSS), and psychomotor slowing (PS). They assessed functional outcomes using the Global Assessment of Functioning (GAF), the Social and Occupational Functioning Assessment Scale (SOFAS), and the UCSD Performance-Based Skills Assessment (UPSA-B). The average age of the participants was 37.9 years and 88 of the 156 were male. The average duration of illness was 12.5 years.
Overall, patients with catatonia and parkinsonism scored significantly lower on GAF and SOFAS scale compared to those without catatonia and parkinsonism (P < .035 and P < .027, respectively).
No significant differences in functional outcomes appeared between patients with and without dyskinesia.
However, significant negative correlations were identified for parkinsonism and PS with GAF, SOFAS, and UPSA-B (P < .036 for all). “Our study further found that parkinsonism and psychomotor slowing also impair the functional capacity of patients,” which may be influenced by factors including deficits in social interaction and cognitive impairment, the researchers said.
Overall, the study findings demonstrate that motor abnormalities in patients with schizophrenia are strongly associated with poor functional outcomes, and the stronger the motor impairment, the worse the global and social functioning, the researchers said.
As for potential pathways, “motor abnormalities are readily observable signs, allowing laypersons to perceive subjects with schizophrenia as somebody with severe mental illness. Thus, motor abnormalities might lead to stigmatization of patients suffering from schizophrenia,” they wrote in their discussion.
The researchers emphasized the need to explore alternative treatment options that might improve motor abnormalities, such as transcranial magnetic stimulation, given the potential of antipsychotic medications to introduce additional motor abnormalities.
The study findings were limited by several factors including the potential for missed confounding variables, the small number of patients with dyskinesia, and the inability to deduce the course of illness because most of the patients were in psychotic episodes, the researchers noted.
However, the results suggest that specific motor abnormalities are associated with poor global and social functioning, and with reduced functional capacity, in adults with schizophrenia, the researchers said. “Future studies need to test whether amelioration of motor abnormalities may improve community functioning,” they concluded.
The study was supported by the Swiss National Science Foundation, the Bangerter Rhyner Foundation, and the Adrian and Simone Frutiger Foundation. Lead author Dr. Nadesalingam had no financial conflicts to disclose.