A longitudinal study of stress-sensitivity trajectories and schizotypy: Retrospective and momentary daily-life assessments of stress appraisals

Heightened stress-sensitivity is a vulnerability factor to the extended psychosis phenotype (i.e., schizotypy), but longitudinal studies on its development and association with schizotypy are lacking. This study examines the stability of stress-sensitivity as a trait and its trajectories over time, assessed both retrospectively and in daily life. Additionally, it explores whether individuals with varying stress-sensitivity trajectories exhibit different levels of positive and negative schizotypy. Stress-sensitivity was measured in non-clinical young adults at three time points (T3 n = 102, age = 23.5; T4 n = 89, age = 25; T5 n = 168, age = 28) both retrospectively with Perceived Stress Scale and momentarily with experience sampling methodology. Schizotypy dimensions were assessed at the final time point. Three longitudinal modeling techniques were used to assess and classify individuals' trajectories of stress over time. Stress-sensitivity exhibited overall stability over time across both retrospective and momentary measures, revealing two trajectory classes (high and low). Stability persisted in high stress-sensitivity classes, except for momentary situational stress. Individuals with persistently high stress-sensitivity over 4.5 years reported elevated positive and negative schizotypy. Retrospective measure revealed a large effect for positive and a medium effect for negative schizotypy, while no such associations for momentary assessments. Findings indicate that stress-sensitivity is a stable trait, even when assessed in young adults. Stability was more effectively captured through retrospective rather than momentary measures-consistent with the contextually-driven nature of momentary responses. These results align with stress-sensitivity role in the causal pathway of the extended psychosis phenotype. Understanding the characterization of stress-sensitivity may offer insight into risk, protection, and mechanisms in psychosis development.