Can youth at high risk of illness progression be identified by measures of rumination and sleep-wake disturbance

Aim: Clinical staging models offer a useful framework for understanding illness trajectories, where individuals are located on a continuum of illness progression from stage 0 (at-risk but asymptomatic) to stage 4 (end-stage disease). Importantly, clinical staging allows investigation of risk factors for illness progression with the potential to target trans-diagnostic mechanisms at an early stage, especially in help-seeking youth who often present with sub-threshold syndromes. While depressive symptoms, rumination and sleep-wake disturbances may worsen syndrome outcomes, the role of these related phenomena has yet to be examined as risk factors for trans-diagnostic illness progression in at-risk youth. Methods: This study is a prospective follow-up of 248 individuals aged 12 to 25 years presenting to headspace services with sub-threshold syndromes (stage 1) classified under the clinical staging model to determine transition to threshold syndromes (stage 2). Factor analysis of depression, rumination and sleep-wake patterns was used to identify key dimensions and any associations between factors and transition to stage 2 at follow-up. Results: At 1 year, 9% of cases met criteria for stage 2 (n = 22). One of three identified factors, namely the factor reflecting the commonalities shared between rumination and sleep-wake disturbance, significantly differentiated cases that transitioned to stage 2 vs those that did not demonstrate transition. Items loading onto this factor, labelled Anergia, included depression severity and aspects of rumination and sleep-wake disturbance that were characterized as introceptive. Conclusions: Common dimensions between rumination and sleep-wake disturbance present a detectable trans-diagnostic marker of illness progression in youth, and may represent a target for early intervention.