Relatively little is known about the course of TD in patients continuing to receive neuroleptic medication. In a retrospective follow-up study of 192 patients seen two or more times (average 7.7 visits) over 3-55 months in the Yale Tardive Dyskinesia Clinic, 112 (58%) demonstrated a 'chronic persistent' pattern, the remainder an 'intermittent' pattern. The most important predictors of chronic persistent TD, using multiple logistic-regression analyses, included increased age and the presence of non-orofacial TD at baseline.