Long term course of bipolar I disorder in India: using retrospective life chart method

Background: There are grounds to believe that the course of bipolar disorder may be different in tropical countries such as India when compared to temperate nations. There is a dearth of literature about the course of bipolar I disorder from India.

Methods: This study was conducted in a multispecialty teaching hospital in southern India. Patients with a DSM-IV TR diagnosis of bipolar I disorder, confirmed using SCID-I, with a minimum duration of illness of 3 years were assessed. Information was gathered on demographic and clinical variables, and the life course of episodes was charted using the National Institute of Mental Health - Life Chart Methodology Clinician Retrospective Chart (NIMH-LCM-CRC).

Results: A total of 150 patients with bipolar disorder were included. The mean age at onset of illness was 24.8 (± 8.2) years. Mania was the first episode in a majority (85%) of the cases, and was the most frequent episode in the course of the illness, followed by depression. Patients spent an average of 11.1% of the illness duration in a mood episode, most commonly a manic episode. The median duration of manic or depressive episode was 2 months. Median time to recurrence after the first episode was 21 months (inter-quartile range of 10-60 months), and was shorter for women than men.

Limitations: The hospital based sample from a particular region limits generalizability. Recall bias may be present in this retrospective information based study. Medical illness, personality disorders, other Axis I psychiatric disorders (apart from substance use disorder) and influence of adherence to treatment on the course of the disorder were not assessed systematically.

Conclusions: Bipolar I disorder among Indian patients has a course characterized by predominantly manic episodes, which is in line with previous reports from tropical countries and substantially different from that of temperate regions.