Anatomical, functional connectivity and gray matter development as risk factors for bipolar disorders - longitudinal MRI study in offspring of bipolar parents

Bipolar disorder (BD) is a severe mental illness affecting tens of thousands of Canadians. It ranks as the 6th most important cause of disability according to the World Health Organization. BD imposes a high burden to patients, their families and society. While the cause of BD is not yet known, the role of genetic factors has clearly been established. Relatives of bipolar patients inherit subtle changes in the structure of the brain, which increase their vulnerability for BD (biological risk factors). Some of the neuroimaging findings in bipolar patients represent biological risk factors whereas others are secondary to progression/burden of the illness. The best way to identify the biological risk factors is to study affected and unaffected offspring of bipolar parents. Any changes found in both the affected and unaffected offspring of bipolar parents, relative to healthy controls without family history of BD likely represent inherited biological risk factors. The best way to directly study the effects of BD on brain structure, is to follow subjects with BD over time. We propose to undertake a study of offspring of bipolar parents between 15 and 30 years of age, to identify biological risk factors for BD. We will carry out brain imaging, in order to identify subtle differences in brain structure and function between offspring of bipolar parents and controls. We will also compare our findings with results of our initial study done 4 years ago in order to find whether there are differences in brain development between controls and offspring of bipolar patients (effects of illness burden). This study will provide greater understanding of biology and development of BD. Identification of biological risk factors might aid in early diagnosis and intervention thus markedly decreasing the economic and human burden of the illness, which would be of paramount importance not only to patients and their families, but also to general public.