The effect of systemic antidepressant treatments in early stage on neurocognitive function of euthymic bipolar patients initiated with a depressive onset: An observational, cross-sectional, single-blind study protocol

Objectives Patients with bipolar disorder (BD) have a wide range of neurocognitive dysfunction even in euthymic state, leading to impaired psychosocial function and reduced quality of life. However, the understanding on risk factors related to neurocognitive impairment in such group of people is limited. In view of significantly delayed diagnosis of BD and common use of antidepressants prior to the BD diagnosis, the study aims to clarify whether systemic antidepressant use in early stage, defined as from the initial depressive episode to the diagnosis of BD, could impact neurocognitive function of euthymic bipolar patients. Methods It is an observational, cross-sectional, single-blind trial, making a comparison in neurocognitive function between euthymic bipolar patients who had a depressive episode as initial onset and being with and without systemic antidepressant treatments in early stage (n = 62 and 62, respectively); secondary outcomes include the impact of systemic antidepressant use on global function, quality of life, sleep quality, positive and negative affect, and peripheral level of neuron-specific enolase. Discussion The study will provide a comprehensive and in-depth understanding on the effect of systemic antidepressant treatments in early stage in such group of patients. It is expected to better guide the related prevention and treatment work of BD management. Trial Registration The study was registered on Clinicaltrials.gov with protocol ID (TJAH2020-18) and clinicaltrials.gov ID (NCT04564573).