Bipolar disorder and parental psychopathology

Area of Science:

• Psychiatry
• Genetics
• Epidemiology

Background:

• Parental psychopathology is a known risk factor for offspring bipolar disorder (BPD).
• Previous studies have limitations in controlling for socio-economic status, maternal smoking, and parental diagnoses made before offspring birth.
• Understanding these familial links is crucial for early identification and intervention strategies.

Purpose of the Study:

• To investigate the association between parental psychiatric disorders and the risk of BPD in offspring.
• To examine associations for parental disorders diagnosed at any time and specifically those diagnosed before offspring birth.
• To control for potential confounding factors like parental education and maternal smoking.

Main Methods:

• A nested case-control study utilizing Finnish national registers.
• Inclusion of 1,861 cases of BPD in offspring (up to age 25) and 3,643 matched controls.
• Conditional logistic regression analysis, adjusting for covariates including parental age, education, and maternal smoking during pregnancy.

Main Results:

• Parental BPD showed strong associations with offspring BPD (OR maternal 5.2, paternal 8.1).
• Parental schizophrenia and related psychoses also significantly increased offspring BPD risk (OR maternal 3.1, paternal 4.5).
• Other parental affective and anxiety disorders were associated with increased offspring BPD risk, with significant findings for diagnoses made before offspring birth.

Conclusions:

• BPD in offspring is linked to a range of parental psychiatric disorders, notably parental BPD and schizophrenia.
• The observed associations are partly attributable to child-independent factors.
• Statistical adjustments for covariates minimally impacted the strength of these associations.