The Impact of Prophylactic Medication Use on the Recurrence of Bipolar Episodes in the BDRN Pregnancy Study

AIMS: Women with bipolar disorder have a high recurrence rate in the perinatal period. However, the use of prophylactic medication can be a concern during pregnancy and breastfeeding. There are few studies looking at the impact of prophylactic medication on the risk of recurrence.The aims of this study are to describe the use of medication in women with bipolar disorder in the perinatal period and the impact of that prophylactic medication on the rate of postnatal recurrence. METHODS: The BDRN (Bipolar Disorder Research Network Study) is the largest individual network of individuals with bipolar disorder and related mood disorders in the world. The BDRN pregnancy study is a prospective observational study which took place in the UK. We collected sociodemographic, clinical and medication data from pregnant women with a diagnosis of bipolar disorder and who were euthymic entering the postpartum period. The clinical data were collected via interviews during pregnancy and the postpartum and access to clinical records where those were available. Data were analysed for association using χ(2) tests and logistic regression. RESULTS: Our total sample for this analysis comprised of 103 women who met the criteria. We found that 71 (70%) were taking medication at delivery: 43 (43%) antipsychotics, 9 (9%) antidepressants, 10 (10%) mood stabilisers, (6 lithium, 4 anticonvulsants and 9 multiple medication classes). Of the total sample, 44 (43%) experienced a postpartum recurrence: 21 (20%) had an episode of postpartum psychosis, 15 (15%) of non-psychotic depression and 8 (8%) of hypomania. Of the postpartum psychotic episodes 11 were of mania with psychosis, 8 of mania without psychosis and 2 of psychotic depression. There was no significant association between taking medication at delivery and postpartum recurrence χ(2) (1)=0.116, p=0.73. In a multivariable analysis there continued to be no association when adjusted for age, ethnicity, parity, severity (previous admissions, age at impairment, bipolar subtype) and previous psychotic symptoms aOR 1.35 95%CI [0.45; 4.00], p=0.59. CONCLUSION: A high number of bipolar women are taking medication at delivery and in the majority, antipsychotics are prescribed. The postnatal recurrence rate in both medicated and unmedicated women is high. Our findings align with recent electronic health records and observational studies, but differ from older clinical cohort and higher Lithium-prescribing sample studies. Limitations include the study design and confounding by indication. Further research in larger populations is necessary to inform clinical decision-making for women and their healthcare providers.