Bipolar disorder is quite heterogeneous; first-episode polarity has been proposed as course predictor.

This study aimed to compare sociodemographic and clinical aspects, as well as illness course, in bipolar 1 disorder patients according to the polarity of the first episode.

We conducted a retrospective and comparative survey of all patients hospitalized in the department of psychiatry “A” in the Hedi Chaker University Hospital, in Sfax (Tunisia), during the period from January 2008 to December 2012, and in whom bipolar 1 disorder was diagnosed (DSM IV-TR).

Patients whose follow-up does not exceed one year were excluded. Subjects were sorted into two groups: group ’M” those with manic/hypomanic first episode and group ’D” those with depressive one.

Seventy-six patients were included (group ’M” = 58; group ’D” = 18).

The depressive first episode was significantly correlated with early-onset of bipolar disorder (p = 0.01), more frequent family history of bipolar disorder (p = 0.02), more suicide attempts (p = 0.00) and higher number of mood episodes (p = 0.02).

Group ’M” had more frequently psychotic features (p = 0.00) and more psychiatric hospitalization history (p = 0.04).

No statistical difference was found in gender and substance abuse between the two groups.

Our study confirmed literature data that bipolar patients with depressive onset seem to have a poorer prognosis.