The Lausanne-Geneva cohort study of offspring of parents with mood disorders: methodology, findings, current sample characteristics, and perspectives

Abstract

Purpose: Studies focusing on the offspring of affected parents utilize the well-established familial aggregation of mood disorders as a powerful tool for the identification of risk factors, early clinical manifestations, and prodromes of mood disorders in these offspring. The major goals of the Lausanne-Geneva mood cohort study are to: (1) assess the familial aggregation of bipolar and unipolar mood disorders; (2) prospectively identify risk factors for mood disorders as well as their early signs and prodromes; (3) identify their endophenotypes including cognitive features, alterations in brain structure, HPA-axis dysregulation, and abnormalities of the circadian rhythm of activity.

Methods: Probands with bipolar disorders, major depressive disorder, and controls with at least one child aged from 4 to 17.9 years at study intake, their offspring, as well as their spouses are invited to take part in follow-up assessments at predetermined ages of the offspring. Direct semi-structured diagnostic interviews have been used for all participants. Probands, spouses, and adult offspring also undergo neurocognitive testing, anthropomorphic measures and biochemical exams, structural Magnetic Resonance Imaging, as well as objective assessments of physical activity using accelerometers in combination with ecological momentary assessments.

Results: Currently, our study has up to seven follow-up assessments extending over a period of 20 years. There are 214 probands and 389 offspring with one direct interview before age 18 as well as a second assessment over follow-up. Data on 236 co-parents are also available from whom 55% have been directly interviewed. First publications support the specificity of the familial aggregation of BPD and the strong influence of an early onset of the parental BPD, which amplifies the risk of developing this disorder in offspring.

Conclusions: Information from clinical, biological, cognitive, and behavioral measures, based on contemporary knowledge, should further enhance our understanding of mood disorder psychopathology, its consequences, and underlying mechanisms.

Keywords: Endophenotypes; Familial aggregation; Offspring of bipolar and depressed parents; Prospective study; Risk factors.