Cognitive functioning in bipolar disorder : the influence of sex

Following a wave of similar research conducted in samples with schizophrenia, there has been a recent surge of studies investigating sex differences in the phenomenology of bipolar disorder (BD). These studies have almost exclusively focused on sex differences in course and clinical presentation. As compared with male BD patients, women with BD have increased likelihood of experiencing rapid cycling, mixed mania, suicidal ideation, and a medical or psychiatric comorbidity. However, in addition to its characteristic affective disturbance, the phenomenology of BD is associated with significant and persistent cognitive impairment. There is evidence to support that sexual dimorphisms, the basis of sex differences in cognitive functioning, are altered in BD. Additionally, it has been found that healthy patterns of cognitive sex differences are disrupted in schizophrenia, a closely related illness to BD. Despite this evidence, there have been few studies that have investigated the influence of sex on cognitive functioning in BD; the results that are available are both scant and contradictory. In order to clarify whether sex influences cognitive functioning in BD, 66 patients with BD-I disorder and 105 matched healthy controls were tested on a broad battery of neuropychological tests. As patients used in this sample were tested immediately proceeding symptomatic remission from their first-manic episode, this experimental design is poised to assess sex differences in cognitive functioning early in the course of BD. Overall, unlike in schizophrenia, healthy patterns of cognitive sex differences are intact early in the course of BD. To supplement and contextualize the study presented above, a large portion of this thesis is dedicated to providing literature reviews of the following topics: sex differences in the clinical phenomenology of BD, cognitive impairment in BD, sex differences in cognitive impairment and their neurobiological underpinnings in healthy samples.Medicine, Faculty ofGraduat