Objectives: Disturbances in cognition, affect, sleep and activity have been identified in bipolar disorder (BD) but little is known about the possible role of these factors in the development of the condition. We studied these variables in a familial high-risk sample.
Methods: Twenty-five children (13-19 years) of bipolar parents were compared with 22 similar aged children of age- and sex-matched healthy controls. Participants were assessed using Schedule for Affective Disorders and Schizophrenia-Lifetime version (SADS-L) and completed self-report measures of dysfunctional attitudes, behavioural inhibition/activation, social rhythms, coping styles and subjective experience of sleep. Children completed a 7-day recording of actigraphy (sleep and activity) and a 7-day diary measuring self-esteem, positive and negative affect and reactions to positive and negative events.
Results: Fifty-six per cent of children of bipolar parents (CBP) reported mood symptoms compared to 9% of children of control parents (CC). The CBP group had coping styles and instability of self-esteem consistent with abnormal strategies for regulating affect. Both groups also differed on sleep measures. The majority of differences observed were between CBP with a current or past mood diagnosis and CC. BD parents reported dysfunctional coping styles and (to a lesser extent) disrupted activity patterns.
Conclusions: A familial high-risk strategy for studying the role of psychological factors in BD is feasible and informative. This pilot study indicates that abnormal coping styles, instability of self-esteem and dysregulation of sleep may be early markers of bipolar illness. However, current findings need to be explored further in longitudinal studies to clarify which potential markers are truly predictive of BD.