Loneliness and Depression in Daily Life: A Multilevel Ecological Momentary Assessment Study of the Moderating Role of Future Time Perspective

Background Depressive disorders are characterized by persistent negative emotional states and cognitive impairments that significantly impact quality of life. Loneliness is a key predictor of depression and interacts with future time perspective(FTP), a subjective perception of remaining time in life. While FTP influences emotional and behavioral motivations, its role in moderating the loneliness-depression relationship is underexplored. This study used ecological momentary assessment(EMA) to investigate these relationships in daily life. Method Participants completed a 14-day EMA protocol, responding four times daily via smartphone SMS. Emotional states were measured using a visual analogue scale (VAS) for 14 negative affects and one positive affect. multilevel modelling (MLM) examined within- and between-individual effects and FTP's moderating role. Results Participants (aged 19–50 years) completed 3,183 EMA observations with an adherence rate of 96.3%. The final dataset consisted of 3,304 data points from 56 assessments (level 1) and 59 participants (level 2), with an average response rate of 96.48%. Loneliness significantly predicted depression at the within-individual level, with substantial between-individual variation in this relationship. In addition, FTP moderated the effect of loneliness on depression, suggesting its potential buffering role. Conclusions This study demonstrates the utility of EMA in capturing real-time emotional dynamics and highlights FTP's protective role against loneliness-induced depression. The findings support the use of digital tools for real-time monitoring and interventions, as well as strategies like future-oriented group training (FOGT) and social support programs to mitigate depression's impact. These approaches offer practical solutions to improve mental health care.