Objective: Bipolar disorder often co-occurs with post-traumatic stress disorder, yet few studies have investigated the impact of post-traumatic stress disorder in bipolar disorder on treatment outcomes. The aim of this sub-analysis was to explore symptoms and functioning outcomes between those with bipolar disorder alone and those with comorbid bipolar disorder and post-traumatic stress disorder. Methods: Participants (n = 148) with bipolar depression were randomised to: (i) N-acetylcysteine alone; (ii) a combination of nutraceuticals; (iii) or placebo (in addition to treatment as usual) for 16 weeks (＋4 weeks discontinuation).Differences between bipolar disorder and comorbid bipolar disorder and post-traumatic stress disorder on symptoms and functioning at five timepoints, as well as on the rate of change from baseline to week 16 and baseline to week 20, were examined. Results: There were no baseline differences between bipolar disorder alone and comorbid bipolar disorder and post-traumatic stress disorder apart from the bipolar disorder alone group being significantly more likely to be married (p = 0.01). There were also no significant differences between bipolar disorder alone and comorbid bipolar disorder and post-traumatic stress disorder on symptoms and functioning. Conclusion There were no differences in clinical outcomes over time within the context of an adjunctive randomised controlled trial between those with bipolar disorder alone compared to those with comorbid bipolar disorder and post-traumatic stress disorder. However, differences in psychosocial factors may provide targets for areas of specific support for people with comorbid bipolar disorder and post-traumatic stress disorder.

Objective: There is often a shortfall in recovery following treatment for an episode of bipolar disorder (BD). Exploration of participant’s experience provides vital information to enhance statistical outcomes for novel therapy trials. This study used mixed-methods to explore participants’ experience of a trial testing N -acetyl cysteine (NAC) and mitochondrially active nutraceuticals for BD depression. Methods: Case report forms from a randomised controlled trial (RCT) of BD depression (n = 148) were analysed using a pragmatic adaption of grounded theory and thematic analysis. Results: Thematic analysis of 148 study participants indicated numerous changes in participant experience over time. For example, perceived environmental stressors reported by participants decreased over the trial in both treatment groups. Quantitative analysis of the themes revealed more positive theme reports in the combination treatment arm compared to the placebo arm and there were more negative themes identified in the placebo arm, compared to the NAC arm. Conclusion This approach revealed additional results not elucidated in the primary quantitative analysis. This emphasises the value of mixed-methods research in capturing participants’ experiences in RCTs and detecting possible latent benefits and risks. Such methods can detect latent target signals in novel therapy trials conducted in BD and generate novel hypotheses.