Multidimensional outcomes associated with chronic fatigue over 12 months in youth with emerging mood disorders

Complaints of chronic fatigue lasting weeks or longer are common during adolescence. Little is known about factors associated with chronic fatigue in youth with mood disorders or potential sex-specific associations.

496 young people (mean age = 18.36-years, SD = 3.22; 69 % female) seeking help for mental healthcare were assessed on psychological symptoms, lifestyle, and sleep at baseline and 12-months later. Fatigue was defined as a score of ≥3 on the somatic subscale of the Somatic and Psychological Health Report. Logistic regression models were used to examine associations between clinical, lifestyle, and related factors and chronic fatigue caseness, including main effects and sex interactions.

Half (52 % [N = 260]) of the sample reported fatigue at both baseline and 12-month follow-up ("chronic fatigue"). Univariately, chronic fatigue cases were more commonly at later clinical stages of mental disorder and had worse mental health, sleep disturbance, and disability at baseline and follow-up. In covariate-adjusted analyses, being a chronic fatigue case was associated with persistently elevated anxiety and, at 12-month follow-up, more disability, weight gain, and shorter sleep duration. In sex-interaction analyses, chronic fatigue in females was associated with longer sleep latency at follow-up (OR = 1.97), but not in males.

Chronic fatigue was common and associated with poorer mental health and functioning longitudinally. While there were no sex differences in the rates of chronic fatigue, there were some sex differences in the factors associated with it. Systematic screening and early intervention for chronic fatigue, considering sex-specific factors, may improve multidimensional outcomes in youth with emerging mood disorders.