The Long-term Natural History of the Weekly Symptomatic Status of Bipolar I Disorder

To our knowledge, this is the first prospective natural history study of weekly symptomatic status of patients with bipolar I disorder (BP-I) during long-term follow-up.

Analyses are based on ongoing prospective follow-up of 146 patients with Research Diagnostic Criteria BP-I, who entered the National Institute of Mental Health (Bethesda, Md) Collaborative Depression Study from 1978 through 1981. Weekly affective symptom status ratings were analyzed by polarity and severity, ranging from asymptomatic, to subthreshold levels, to full-blown major depression and mania. Percentages of follow-up weeks at each level as well as number of shifts in symptom status and polarity during the entire follow-up period were examined. Finally, 2 new measures of chronicity were evaluated in relation to previously identified predictors of chronicity for BP-I.