Distinct Associations Between Psychopathological Distress and Sleep Quality in Good and Poor Sleepers

Background: Sleep quality commonly declines with advancing age and is closely linked to psychological distress through intricate and bidirectional mechanisms. Although this relationship is well established, less is known about whether psychopathological symptoms differentially affect specific dimensions of sleep among individuals with varying levels of sleep impairment. The present study aims to investigate the role of psychopathological distress on multiple components of sleep quality in good and poor sleepers. Methods: Two hundred and seventy-three participants (aged 50-91) were divided into good sleepers (n = 145) and poor sleepers (n=128) using the Pittsburgh Sleep Quality Index (PSQI) cut-off. Psychological distress was evaluated using the Symptom Checklist-90 (SCL-90). Results: ANOVAs revealed that poor sleepers reported significantly higher distress across all clinical subscales and global indices of SCL-90 (p<.001). Correlation analyses revealed different patterns between groups. Among good sleepers, psychological distress was mainly associated with sleep latency, suggesting a circumscribed impact on sleep onset. Conversely, among poor sleepers, psychological distress showed broader correlations with sleep disturbance, daytime dysfunction, and global PSQI scores. Hierarchical linear regressions confirmed that adding the Global Severity Index (GSI) to the model, after controlling for demographic covariates, significantly improved model fit in both groups. However, psychological distress accounted for a higher proportion of variance in Poor Sleepers (R2=.14, Delta R2=.10, p<.001) than in good sleepers (R2=.05, Delta R2=.04, p=.012). Conclusions: These findings suggest that psychological distress may act as apervasive perpetuating factor when sleep is already compromised. These findings highlight the importance of considering psychopathological burden when addressing sleep problems in later life and support the development of tailored interventions targeting both emotional distress and sleep dysfunction.