Background: Bidirectional next-day associations between sleep disturbances and affective symptoms have been shown in previous research, yet the consecutive day effects between these factors remains poorly understood. Methods: We analysed longitudinal ecological momentary assessment (EMA) data obtained from a subsample of young persons in the Brazilian High-Risk Cohort (BHRC) study collected in 2020-2021. Participants reported sleep quality each morning and rated affective symptoms relating to mood, anxiety, and energy four times daily for 28 days. We selected 88 individuals (17.83{+/-}1.74 years, 56 [63.6%] female gender) with at least one instance where individuals were observed three-days in a row. Within-person bidirectional next-day effects between sleep quality and affective symptoms were estimated using mixed-effects regression analysis adjusting. We then applied g-estimation approaches to estimate the effect that lagged sleep quality and consecutive improvements in sleep quality had on affective symptoms. Results: Sleep quality and affective symptoms had bidirectional next-day effects, with sleep quality tending to have greater influence on affective symptoms than the reverse. Improved lagged sleep quality had positive effects on affective symptoms incrementally above the prior night's sleep quality. Also, improvement of sleep quality across consecutive days had incremental and approximately equal effects on affective symptoms. Conclusions: Sleep quality and affective symptoms exhibit a feedback loop, whereby poor sleep quality influences affective symptoms over consecutive days. Breaking these feedback loops, by improving sleep quality across several consecutive nights should improve affective symptoms. This supports interventions that target sustained improvement in sleep and possibly circadian regulation to improve affective symptoms.
M. Varidel, L. Borgnolo, V. An et al.· medRxiv· 0 citations
BACKGROUND
Major Depressive Disorder (MDD) is heritable and polygenic, yet the relative diagnostic specificity, developmental impact, and cross-ancestry generalizability of MDD polygenic risk scores (MDD-PRS) remain unclear.
METHODS
In two sites of the Brazilian High-Risk Cohort (N=2,163; ages 6-23; 45.6% female), we used a discovery-replication design to test associations between MDD-PRS and (i) lifetime DSM-IV diagnoses; (ii) longitudinal depressive-symptom trajectories from latent growth-curve models; and (iii) late-adolescent/young-adult depressive symptoms and nonsuicidal self-injury (NSSI). Analyses used weighted ordinary least squares and quantile regression, adjusting for age, sex, socioeconomic status, genetic principal components, and psychiatric comorbidity.
RESULTS
MDD-PRS showed relative specificity for MDD in both sites, explaining approximately 2.6-3.6% of liability-scale variance; no other diagnostic category survived false-discovery-rate correction. Longitudinally, higher MDD-PRS predicted higher initial level (β=0.10-0.18; p<0.001 in both sites), faster rate of increase (β=0.07-0.10; p=0.004 and p<0.001), and higher time-averaged level (β=0.13-0.20; p<0.001 in both sites) of depressive symptoms, with effects strengthening at higher quantiles. Cross-sectionally, MDD-PRS were associated with more depressive symptoms (β=0.15-0.17; p<0.001 in both sites). For NSSI, a main-effect association was observed (β=0.09; p<0.001), but it remained significant only in a post-hoc MDD-PRS×lifetime-MDD interaction among individuals with MDD (β=0.24; p=0.014).
CONCLUSIONS
In this deeply phenotyped, admixed cohort, MDD-PRS showed relative diagnostic specificity and marked a more severe developmental course of depression, with NSSI associations contingent on MDD diagnosis, supporting the relative specificity, developmental utility, and cross-ancestry relevance of MDD-PRS.
M. Brañas, L. T. Ito, M. Croci et al.· Biological Psychiatry· 0 citations