The effects of negative life events on depression in middle-aged women: the mediating role of rumination and coping styles

Background The mental health of middle-aged women is a significant public health issue. Based on Response Styles Theory (RST), this study aims to investigate the associations between negative life events (NLEs), rumination, coping styles, and depression among middle-aged Chinese women, and to explore the chain mediation mechanism of rumination and positive coping styles. Methods A cross-sectional survey was conducted among 327 middle-aged women aged 35–55 (case group: n = 157; control group: n = 170). Assessment tools included the Self-Rating Depression Scale (SDS), Life Events Scale (LES), Ruminative Response Scale (RRS), Simplified Coping Style Questionnaire (SCSQ), and Pittsburgh Sleep Quality Index (PSQI). Data were analyzed using SPSS 25.0, and the chain mediation effect was tested using the PROCESS macro. Results (1) The case group scored significantly higher than the control group on depression and sleep disturbance. (2) Correlation analysis showed that NLEs, rumination, and positive coping styles (negatively) were all significantly associated with depression and sleep quality ( p 0.01). (3) The chain mediation model revealed that NLEs significantly predicted depression ( β = 0.50, p 0.001). Furthermore, NLEs were associated with depression through the chain mediation path of “Rumination → Positive Coping Style,” where increased rumination predicted decreased positive coping strategies. Conclusion Negative life events are closely associated with decreased sleep quality and exacerbated depressive symptoms in middle-aged women. This relationship is mediated by the chain effect of “Rumination → Decreased Positive Coping Style,” suggesting that rumination may interfere with the adoption of positive coping mechanisms. Interventions should prioritize reducing rumination and enhancing positive coping strategies to alleviate depression and improve sleep quality.