We know that it can take many years for people with bipolar disorder to be accurately diagnosed, following an initial episode of mental illness.
This cohort study carried out by researchers from Denmark, the US and Wales, set out to study to what extent psychiatric disorders with postpartum onset (following childbirth) are early manifestations of an underlying bipolar affective disorder.
The study involved 120,378 women with a mental health disorder (excluding bipolar disorder) and a first-time psychiatric inpatient or outpatient experience.
The participants were followed up after discharge from hospital and the outcome of interest was a first-time diagnosis of bipolar affective disorder during the follow-up period.
Here’s what they found:
- 3,062 women were readmitted or had an outpatient contact with bipolar affective disorder diagnoses
- Women who experienced mental health symptoms within 14 days of giving birth had a predicted subsequent conversion to bipolar disorder (relative risk = 4.26; 95% CI =3.11-5.85)
- 14% of women who experienced mental health symptoms within 1 month of giving birth converted to a bipolar diagnosis within the 15-year follow-up period
- 4% of women with a first psychiatric contact not related to childbirth converted to a bipolar diagnosis within the 15-year follow-up period
- Postpartum inpatient admissions were also associated with higher conversion rates to bipolar disorder than outpatient contacts (relative risk = 2.16; 95% CI = 1.27-3.66)
The authors concluded:
A psychiatric episode in the immediate postpartum period significantly predicted conversion to bipolar affective disorder during the follow-up period. Results indicate that the presentation of mental illness in the early postpartum period is a marker of possible underlying bipolarity.
Munk-Olsen T, Laursen TM, Meltzer-Brody S, Mortensen PB, Jones I. Psychiatric Disorders With Postpartum Onset: Possible Early Manifestations of Bipolar Affective Disorders. Arch Gen Psychiatry. 2011 Dec 5. [Epub ahead of print] [PubMed abstract]