Long-term follow-up of patients treated for psychotic symptoms that persist after stopping illicit drug use

BACKGROUND The long-term outcome of patients diagnosed with drug-induced psychotic disorders in China is unknown. AIM Assess the course of illness and severity of psychiatric symptoms in patients previously admitted to a psychiatric hospital for treatment of psychotic symptoms that were induced by the use of illicit drugs. METHODS Patients with psychotic symptoms at the time of their first psychiatric admission who had used illicit drugs in the month prior to admission were followed up 13 to 108 months after admission. Patients and coresident family members were interviewed about post-discharge drug use and psychotic symptoms. RESULTS The 258 identified patients were primarily young, unemployed males whose most common drug of abuse was methamphetamines and who had been abusing drugs for an average of 7 years at the time of admission. Among these patients 189 (73%) were located and reinterviewed; 168 (89%) had restarted illicit drug use and 25 (13%) had required rehospitalization over the follow-up period. In 114 patients (60%) the psychotic symptoms resolved in less than 1 month after stopping the drugs, in 56 (30%) the symptoms persisted for 1 to 6 months, and in 19 (10%) the symptoms persisted for longer than 6 months (in 8 of these the diagnosis had changed to schizophrenia). Compared to the other two groups, patients whose symptoms persisted more than 6 months were more likely to have a family history of mental illness, an earlier age of onset and a longer duration of drug abuse prior to the index admission; they were also more likely to have been re-hospitalized during the follow-up period and to have psychotic symptoms at the time of follow-up. CONCLUSION Most patients with substance-induced psychotic disorders in our sample had a good long-term prognosis but those who started illegal drug use early, used drugs for prolonged periods, or had a family history of psychiatric illnesses were more likely to develop a chronic psychosis. Further prospective studies are needed to determine the relationship of the neurotoxic effects of illicit drugs and the predisposing characteristics of the individuals in the development of chronic psychosis in persons who use illicit drugs.