(PS5-8) Sex and Developmental Effects on Depressive and Hypomanic Symptoms in Adolescents at Risk for Developing Bipolar Spectrum Disorders

Abstract Text:

Objective: Sex differences may exist in symptoms of bipolar spectrum disorders (BSDs) in adults. However, the developmental trajectories of these differences and whether they exist in adolescence, a period of heightened risk for first onset of BSD, are unknown. This study’s goal was to identify sex and developmental effects on adolescents’ mood symptoms. We hypothesized that depressive symptoms would be endorsed more frequently by females and that hypomanic symptoms would be endorsed more by males. We predicted that mood symptoms would increase with time from baseline.

Method: 75 adolescents (56% female) aged 13-16 were recruited for an ongoing longitudinal study examining the first onset of BSDs. Participants at high risk for BSD onset (i.e., operationalized as high trait reward responsiveness) were oversampled. Participants completed self-report mood measures at baseline as well as at six months and one year.  The Altman Self-Rating Mania Scale, Beck Depression Inventory-II, and Child Mania Rating Scale were administered at all three timepoints. The General Behavior Inventory 10 Mania 10 Depression Scales were administered at baseline and one year. Split plot ANOVAs were conducted on each item to examine effects for individual symptoms.

Results: Sex effects were present for many depressive symptoms, all with a greater frequency in females. These symptoms included: depressed mood, anhedonia, irritability, anxiety, rumination, mood reactivity, self-deprecation, restlessness, crying, difficulty concentrating, lack of energy, hypersomnia, and appetite changes (all p’s < .05). Developmental effects were observed for several depressive symptoms, all of which were endorsed with greater frequencies at baseline than at six months or one year. These symptoms were: depressed mood, anhedonia, anxiety, rumination, mood reactivity, self-deprecation, guilt, hypersomnia, and suicidality (p’s < .05). There were also sex effects observed in three hypomanic symptoms: more irritability in females; and increased frequencies of sexually inappropriate behavior and decreased need for sleep in males (p’s < .05). Developmental effects were present for many hypomanic symptoms, including: mood elevation, mood swings, increased activity, increased self-confidence, psychomotor agitation, increased talkativeness/flight of ideas, racing thoughts, decreased need for sleep/insomnia, and sexually inappropriate behavior (p’s < .05). Of these, all but racing thoughts were endorsed with greater frequencies at baseline than six months or one year. Results were generally consistent for individual items assessing the same construct across different measures.

Conclusions: Sex differences in depressive symptoms were consistent with higher rates of depression in females, and a few hypomanic symptoms were endorsed more frequently by males. Interestingly, developmental effects were present for many mood symptoms with higher frequencies endorsed at baseline than at six months or one year, contrary to expectations that mood symptoms would increase with time. This could be because of greater life stress before baseline, underreporting symptoms at follow-up to reduce study participation time, or drop-out of participants with increasing symptoms.