Risk factors for tardive dyskinesia according to primary psychiatric diagnosis.

The role of different variables in the development of tardive dyskinesia was examined among patients in two different diagnostic categories. Age and length of hospitalization were associated with development of tardive dyskinesia in the schizophrenic subjects while parkinsonism and alcoholism were related to tardive dyskinesia in the affective disorder patients. Schizophrenic subjects constituted the largest absolute number of tardive dyskinesia patients, but in relative terms they represented the patient population least likely to develop tardive dyskinesia in comparison to affective disorder and organic mental disorder subjects. The clinical implications of these findings are discussed.