Neurobiology and temperament in the offspring of excellent lithium responders.

OBJECTIVES

The aim of the study was to assess neurobiological and temperamental correlates in offspring of lithium-treated patients, related to parental lithium response.

METHODS

The study comprised 27 female and 23 male subjects, aged 17-54 years, the offspring of 36 bipolar patients receiving lithium for 5-38 years. Thirteen subjects were offspring of excellent lithium responders (ELR), 25 of partial lithium responders and 12 of lithium non-responders. In all subjects, serum brain-derived neurotrophic factor (BDNF), matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) were measured, and the subjects were assessed by the Temperament Scale of Memphis, Pisa, Paris, and San Diego Auto-questionnaire (TEMPS-A) and the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE) scale.

RESULTS

In offspring of the ELR, the percentage of persons treated for mood disorder was higher (46 vs. 16%), and higher mean BDNF and MMP-9 levels and lower IL-6 levels were found, compared with the remaining subjects. There were also differences between the ELR and the remaining patients on the TEMPS-A and O-LIFE scale, and within the ELR, between subjects treated for mood disorders and the healthy ones.

CONCLUSIONS

The offspring of ELR show distinct neurobiological and temperamental profiles compared to other lithium-treated patients.