Nutritional status, mitochondrial function and aerobic capacity as biomarkers of illness course in acute episodes of bipolar disorder

[eng] INTRODUCTION: Bipolar disorder (BD) is a psychiatric disorder with a prevalence of around 2.4%, characterized by recurrent episodes of depression, mania, or hypomania, alternating with periods of euthymia, which suggests a biphasic pattern of energy availability in this disease. Despite adequate treatment, BD is associated with reduced quality of life and psychosocial functioning, especially in those patients with a higher number of relapses. Patients with BD present a higher prevalence of psychiatric but also medical comorbidities, especially metabolic, and a deficient nutritional status, compared to the general population. However, the impact of nutritional status on the course of the disease has been scarcely described. HYPOTHESES: In BD, a biphasic pattern of energy availability will be observed, with an increase in mania and a decrease in depression, compared to euthymia, which will be observed through analyses of mitochondrial respiration and aerobic capacity during physical exercise. Differences in mitochondrial respiration capacity will also be observed between acute episodes of BD and healthy controls. Thus, a positive correlation between aerobic capacity and mitochondrial respiration will be found both during affective episodes and in euthymia. Moreover, patients admitted to a Psychiatry hospitalization unit, especially those with BD, will present nutritional and metabolic alterations associated with the course of the disease in the short term, influencing the duration of hospitalization, and in the long term, associating with the number of relapses in subsequent years. OBJECTIVES: The main objective is to identify potential variations in bioenergetic parameters between acute episodes of BD and symptomatic remission, by studying the oxygen consumption capacity of the mitochondrial electron transport chain (ETC) and aerobic capacity during physical exercise. Additionally, this project aims to compare differences in the oxygen consumption capacity of the mitochondrial ETC between acute mood episodes in patients with BD and healthy controls, and determine the correlation between mitochondrial respiration capacity and aerobic capacity in different phases of the disease, for the identification of potential state-dependent biomarkers in BD. Secondary objectives include characterizing the nutritional profile of patients admitted to a Psychiatry hospitalization unit, with a special focus on BD, and determining its association with markers of illness course in the short or long term, including the duration of hospitalization and readmissions for acute mood episodes in the following three years.