Presence of psychological distress symptoms associated with onset-related life events in patients with treatment-refractory depression

BackgroundPrevious studies have reported that various non-life-threatening life events could cause psychological distress symptoms like posttraumatic stress disorder in adults and adolescents. We examined whether patients with treatment-refractory depression (TRD) perceive their experiences of life events, of which they think as triggering the onset of depression, as more serious psychological distress symptoms than remitted or mildly symptomatic patients with major depressive disorder (MDD).MethodsThis study employed a cross-sectional design. We recruited 78 outpatients consisting of 31 TRD patients, 31 remitted MDD patients, and 16 mildly symptomatic MDD patients. We adopted the Impact of Event Scale-Revised (IES-R) to assess the severity of psychological distress symptoms associated with the events that patients thought as triggering the onset of depression. We also evaluated clinical features and variables including the Hamilton Depression Rating Scale (HDRS).ResultsThe mean [±SD] score of the IES-R in patients with TRD (46.7 [15.1]) was significantly higher than in remitted (10.3 [9.9], p<0.001) or mildly symptomatic (31.3 [7.7], p<0.001) patients with MDD. The HDRS scores showed significant correlations with those of the IES-R among all patients (r=0.811).LimitationsThis study was not able to exclude the possibility that the severity of psychological distress symptoms associated with onset-related events could influence the difficult therapeutic course in patients with TRD due to the cross-sectional design.ConclusionsThis study demonstrated that patients with TRD perceive their onset-related life events as serious psychological distress symptoms. This result contributes to understanding the pathophysiology of TRD.