Psychosocial factors cause weekly cycles in the mood and functional impairment of patients with bipolar disorder, independent of their medication use, say researchers.
The study involved 192 patients with bipolar disorder who were involved in a 10-week study and had completed the Patient Mood Chart on at least 75% of days.
Alexis Whitton (Black Dog Institute, Sydney, Australia) and co-workers found that patients tended to have more severe lows at the beginning of the working week and more intense high mood at the weekend, particularly on Saturdays.
On a scale of 0 to 3, patients rated their low mood at an average of about 0.83 on Mondays and Tuesdays; this severity diminished throughout the rest of the week, reaching a minimum of 0.72 points on Saturdays. Consistent with this, functional limitation was most severe on Mondays and Tuesdays, significantly more so than on Thursdays.
“Given that low mood in bipolar disorder constitutes the greatest burden of the disease, psychosocial interventions aimed at dealing with work-related stressors may be particularly useful for targeting low mood in this population”, the team writes in Psychiatry Research.
By contrast, the most severe highs occurred on Saturdays, on which day patients often reported social events as a positive mood trigger (about 12%). Sleep issues remained a predominant negative mood trigger at the weekend, but work stresses were less common than during the week.
“Taken together, these data suggest that variations in mood and functioning may be closely tied to psychosocial triggers that tend to occur on a weekly cycle”, surmise the researchers.
Of note, medication compliance remained fairly constant throughout the week and was not associated with changes in mood or functional impairment.
Whitton et al note that clinical interviews usually assess mood variation in the context of life events, but suggest that they would also “benefit from assessing weekly variation in symptoms so that more subtle yet regularly occurring psychosocial triggers of symptoms can be identified and addressed in psychoeducation and wellbeing plans”.
They add that studies evaluating treatment response in bipolar disorder patients should control for the day of the week on which patients are assessed.
This article first appeared on ‘medWire News’ on 28 May 2014.