The Long‐Term Follow‐Up TIPP Project: LOFT Study Protocol, a 20‐Year Prospective Study of Early Psychosis Patients

INTRODUCTION: Early intervention services (EIS) in psychosis are the gold standard to treat patients after a first episode of psychosis (FEP). However, the understanding of the evolution and the long-term effects of such type of intervention is limited. This study aims to gain insight into the long-term evolution of physical and mental health, as well as the neurobiological outcomes of the patients treated for a FEP. METHODS: The Long-term Follow-up of TIPP (LOFT) is an up to 20-year study within a cohort of patients who completed a three-year EI treatment at Treatment and early Intervention in Psychosis Program (TIPP, in Lausanne, Switzerland) and went through a deep phenotyping prospective multimodal assessment. 720 patients will be contacted and asked to participate in LOFT. Once they are assessed they will be allocated to a timepoint at either 5 (+2), 10 (±2), 15 (±2), and 20 (-2) years after TIPP entry. A follow-up visit will be proposed every 5 years. All participants will be evaluated on psychopathological, functional, and physical health outcomes including metabolic disturbances. A subsample of the patients who previously took part in a biomarker research program (n = 168) whilst at TIPP will be invited to undergo additional assessments (cognition, brain imaging, biofluids collection). Both traditional group-level and machine learning analyses will be conducted. CONCLUSION: Ethical approval has been obtained and recruitment started in 2024, and 111 participants have been recruited so far. LOFT will help reshape and redefine current interventions for subgroups of patients at risk of poorer long-term outcome and to understand the underlying neurobiological mechanisms influencing psychosis evolution.