Associations between actigraphy estimates of sleep and circadian rhythmicity and psychotropic medications in bipolar disorders: An exploratory study

Introduction: Disturbances in sleep and circadian rhythmicity (CR) are frequent in individuals with bipolar disorders (BD). Very few studies explored the associations between psychotropic medications and these disturbances in euthymic BD. Therefore, we aimed at exploring the associations between several classes of medications (lithium, sedative/non-sedative Atypical Antipsychotics (AAP), anticonvulsants, antidepressants, benzodiazepines) and sleep disturbances and CR dimensions in a sample of euthymic individuals with BD.

Methods: We included euthymic adults with BD type 1 or 2 assessed with 21 days of actimetry. We used a Principal Component Analysis (PCA) of sleep and CR estimates to generate dimensions to be studied in association with the current use of psychotropic medications, with adjustments for potential confounding factors.

Results: We included individuals with BD-1 (n = 116) or BD-2 (n = 37). The PCA led to four dimensions of sleep and CR estimates. Benzodiazepines were associated with better sleep quality (p_corrected = 0.032). Aripiprazole was associated with less robust CR (p_corrected = 0.016), but with earlier peak of activity patterns (p_corrected = 0.020). Sedative AAPs were associated with better sleep quality, which was no longer significant after correction. We found no association between lithium or anticonvulsants and CR.

Limitations: The cross-sectional design and the possible non-representativeness of the sample were limitations of our study.

Conclusions: In euthymic individuals with BD, benzodiazepines may have a positive effect on sleep quality, while aripiprazole may have mixed effects on CR (less robust but with earlier peak of activity patterns). No association with lithium or anticonvulsants observed. Further studies are warranted to replicate and extend these results.