Earlier age of first diagnosis in schizophrenia is related to impaired motor control

We examined the control of motor behavior in relation to age of first diagnosis (AFD; an approximation of age of onset) in schizophrenia. We hypothesized that earlier AFD reflects increased vulnerability to the disorder, vulnerability that may be indexed by elevated levels of motor abnormality. AFD, symptom and demographic features, motor performance on a line drawing task, and the presence and severity of dyskinesia and extrapyramidal side effects were evaluated in 65 chronic schizophrenia subjects. More severely impaired motor control was significantly related to an earlier age of diagnosis. Potential confounds, including age, gender, education, length of illness, current medication dosage, symptom status, and motor side effects, did not appear to influence this relationship, although greater chronicity appeared to be independently related to more severely impaired motor control. In summary, the data are consistent with the hypothesis that an earlier AFD is associated with more pronounced motor impairment.