2-YEAR TRIAL OF MAINTENANCE NEUROLEPTIC DOSE REDUCTION IN SCHIZOPHRENIC OUT-PATIENTS - PREDICTORS OF RELAPSE

Low dose maintenance therapy has been proposed as a pharmacological st rategy for reducing exposure to neuroleptic drugs in schizophrenia. Ho wever, reliable predictors of post-dose reduction relapse, which could guide clinicians in selecting patients suitable for this type of trea tment, have not yet been determined. In this study, 41 schizophrenic o ut-patients were assigned, on the basis of their previously clinically determined dosages, to one of two reduced maintenance fluphenazine de canoate regimes (35 mg/4 wks. or 10 mg/4 wks.) and were assessed, subs equently, for a 2-year period. Demographic, clinical and treatment cha racteristics of relapsers (22 patients) and non-relapsers (18 patients ) were compared using univariate and multivariate tests. Four paramete rs: age, course of illness, duration of illness and duration since las t psychiatric hospitalization, suggested, in univariate tests, signifi cant discrimination between relapsers and non-relapsers. Stepwise disc riminant function analyses defined a highly significant function (p<.0 1) which included only 3 predictors of relapse. In order of importance , these predictors were: (1) a history of chronic psychosis (2) male s ex, and (3) an illness of short duration. Parameters such as age, base line rating scales scores, magnitude of dose reduction and baseline ma intenance dose failed to improve the ability to discriminate between r elapsers and non-relapsers. Implications of these findings for clinica l practice are discussed.