Joint associations of parental personality traits and socioeconomic position with trajectories of offspring depression: findings from up to 6925 families in a UK birth cohort

Background Parental personality may influence the course of offspring depression but this is unclear. It is also unknown whether the impact of parental personality on offspring depression is moderated by socioeconomic position (SEP). Our aims were to describe trajectories of depressive symptoms across adolescence for offspring of parents with and without maladaptive personality traits and to test for effect modification by SEP. Methods A longitudinal study in the Avon Longitudinal Study of Parents and Children birth cohort (ALSPAC; ns = 3054 to 7046). Exposures were binary measures of maladaptive parental personality traits and the outcome was depressive symptoms ages 11 to 24 (SMFQ; range 0 – 26). Results Offspring of mothers with high maladaptive traits showed higher levels of depressive symptoms at all ages (SMFQ difference at age 10 = 0.66, CI 0.25 – 1.28, p = 0.02; age 22 = 1.00, CI 0.51 – 1.50, p < 0.001). There was weaker evidence of an association between paternal maladaptive personality traits and offspring depressive symptoms (SMFQ difference at age 10 = 0.21, CI –0.58 – 0.99, p = 0.60; age 22 = 0.02, CI –0.94, 0.90, p = 0.97). We found no consistent evidence of effect modification by SEP. Conclusions Offspring of mothers with high levels of maladaptive personality traits show evidence of greater depressive symptoms throughout adolescence although the absolute increase in symptoms is small. Evidence for the effect of fathers’ personality was weaker. Socio-economic position and maladaptive personality traits appear to be independent risk factors.