Chain mediating effect of insomnia, depression, and anxiety on the relationship between nightmares and cognitive deficits in adolescents

The study explored the differences in nightmare, insomnia, depression, anxiety, and cognitive deficits among adolescents and the chain mediating effects of insomnia, depression, and anxiety on the relationship between nightmares and cognitive deficits in adolescents. An online survey was used to collect demographic data of 6014 adolescents and assess nightmare, insomnia, depression, anxiety, and cognitive deficits using the Chinese Version of Nightmare Distress Questionnaire, Insomnia Severity Index, Patient Health Questionnaire 9, Generalized Anxiety Disorder 7, and Perceived Deficits Questionnaire-Depression. Spearman correlation analysis and the SPSS function "PROCESS macro" were used for correlation and mediation analyses, respectively. Female adolescents, senior high school, and poor academic performance had higher nightmare, insomnia, and cognitive deficit scores; those living in the city had higher depression and anxiety scores. Cognitive deficits were positively correlated with nightmares, insomnia, depression, and anxiety. Further, insomnia, depression, and anxiety had a chain mediating effect between nightmares and cognitive deficits in adolescents. Nightmares indirectly affect cognition deficits by affecting insomnia and then depression and anxiety symptoms. As this was a cross-sectional study, the causal relationship between the variables could not be determined. Moreover, reporting bias and volunteer bias might be present. These findings suggest that clinicians should identify adolescents with frequent nightmares early and provide timely treatment to minimize negative outcomes and possibly limit the chronicity of nightmare disorder. It is significant to maintain the physical and mental health development of adolescents to reduce the risk of insomnia, depression, anxiety, and cognitive deficits.