Movement disorder profile and treatment outcomes in a one-year study of patients with schizophrenia

BACKGROUND This study identified subgroups of patients with schizophrenia who differed on their movement disorder profile and compared their treatment outcomes. METHODS Data from a randomized, open-label, one-year study of patients with schizophrenia who were treated with antipsychotics in usual clinical care settings were analyzed (n = 640). Five measures of movement disorder were incorporated into a single Movement Disorder Index (MDI). Subgroups that differed in their movement disorder profile over the one-year study period were compared on clinical and functional outcomes. RESULTS THREE SUBGROUPS WERE IDENTIFIED: a worsening of MDI in 15% of patients, an improvement in 33%, and no change in 53%. Compared with the other two subgroups, the MDI-worsened subgroup had poorer symptom improvement measured by the Positive and Negative Syndrome Scale (PANSS) total score (mean changes of -11.0, -18.4, and -16.8 for the patients who had a worsening of MDI, no change, and an improvement, respectively), poorer symptom improvement on the PANSS positive and anxiety/depression subscale scores, worsening on the 36-Item Short Form Health Survey (SF-36) physical component summary score, and a higher rate of hospitalization (P < 0.05). CONCLUSION Patients with schizophrenia who experience worsening of their MDI score appear to have poorer clinical and functional outcomes, suggesting that such worsening may be a marker of poorer prognosis.