In the growing research field of early psychosis detection in patients with an at risk mental state (ARMS), most studies focus on the transition to frank psychosis. However, the majority of ARMS patients do not go on to develop frank psychosis and reported transition rates are declining. Little is known about the long-term outcome of these non-transitioned patients (ARMS-NT).

To investigate in preliminary analyses the long-term outcome of ARMS-NT patients with respect to persistence of ARMS signs and symptoms and the rates of late psychotic transition.

The ongoing study “FePsy-BHS-NT” follows up ARMS-NT without transition during at least the first two years for up to 15 years after their initial assessment. ARMS status is ascertained with the Basel Screening Instrument for Psychosis (BSIP). ARMS remission is defined as the absence of attenuated psychotic symptoms or brief limited intermittent psychotic symptoms for at least 12 consecutive months.

In this preliminary sample of 51 ARMS-NT, the majority of patients (70.6%) have remitted from their at risk mental state, 13.7% remain at risk and 15.7% have made a late psychotic transition during the course of long-term follow up (median = 5.75, range 4–11 years after initial assessment).

The considerable rates of ARMS persistence and late psychotic transition indicate that longer follow-up durations than commonly recommended should be contemplated in ARMS patients. Potential predictors of favorable long-term clinical outcome, as well as psychosocial, neurocognitive and other outcomes of ARMS-NT patients will be further evaluated in the present study.

The authors have not supplied their declaration of competing interest.