Prevalence and Clinical Correlates of Residual Symptoms in Remitted Patients with Bipolar Disorder: An Exploratory Study

Objective: This cross-sectional study aimed to evaluate the prevalence and factors associated with residual symptoms (both depressive and manic) in subjects with bipolar disorder (BD).

Materials And Methods: A total of 844 subjects diagnosed BD with an illness of 2 years' duration and minimum of two lifetime episodes and in clinical remission were evaluated for residual symptoms using Hamilton Depression Rating Scale (HAM-D) and Young Mania Rating Scale (YMRS). Based on the severity of residual symptoms, the study groups were divided into four groups.

Results: Sixty-nine percent of the subjects had residual depressive symptoms (i.e., HAM-D score in the range of 1-7) and 59% had residual manic symptoms (i.e., YMRS score in the range of 1-7). The most common residual depressive symptom was psychic anxiety (34%) followed by impaired insight (29%). The most common manic symptom was poor insight (31%) followed by sleep disturbances (25%). Subjects with both sets of residual symptoms had onset of BD at a relatively young age, when compared to those with only residual depressive symptoms. Presence of any comorbid physical illness and substance abuse disorder was significantly higher in those with both sets of residual symptoms.

Conclusions: The present study suggests that a substantial proportion of patients with BD have residual symptoms of both types. Comorbid physical illness and substance use were associated with residual symptoms. Identification and management of residual symptoms are highly essential to improve the overall outcome of patients with BD.