STEP-BD is the largest treatment study of bipolar disorder conducted to date. Lasting five years and with 4,361 participants, the program yielded information that will be studied for a long time to come. STEP-BD (an acronym for Systematic Treatment Enhancement Program for Bipolar Disorder) was funded by the National Institute of Mental Health, the U.S. government agency responsible for research on mental disorders and their treatment.
Almost anyone at least 15 years old with bipolar disorder was eligible to enroll in STEP-BD. The aim of this long-term study was to find out which treatments or combinations of treatments are most effective for treating bipolar episodes and preventing new episodes. Participants could choose to continue their current treatment, change treatment, or enroll in randomized studies. No one was given placebo-only treatment ("sugar" pills).
However, the data gathered in STEP-BD goes far beyond information on the effectiveness of treatment. The researchers are also able to compile information in areas such as:
- Comorbidity of other disorders with bipolar disorder - that is, what percentage of participants were also diagnosed with additional conditions including anxiety disorders, ADD and ADHD, menstrual problems, seasonal affective disorder and others;
- Frequency of suicidality and rapid cycling in the participant population;
- Frequency of tobacco and alcohol use;
- The burden on caregivers of people with bipolar disorder.
Preliminary findings from STEP-BD started to be released while the study was still monitoring participants (the study period ended September 30, 2005). For example, in December 2004 a paper published in the American Journal of Psychiatry discussed the finding that among the study's first 500 participants there is a greater than 50 percent lifetime comorbidity of anxiety disorders with bipolar illness. This indicates that at least one anxiety disorder episode could have occurred at any point in a bipolar patient’s lifetime. The article also noted that these patients have a more difficult course of their illness. (See The Effect of Anxiety Disorders on Bipolar Disorder.)
Also in December 2004, a paper was published in Bipolar Disorders outlining the demographics of the first thousand enrolled participants. The paper reported that the participants were 58.6 percent female and 92.6 percent Caucasian. "Compared with US population and community studies," said the authors, "the first 1000 STEP-BD patients were less racially diverse, more educated, had lower income, and a higher unemployment rate." No conclusions were drawn about the reason for these results, and it will be interesting to see whether the full roster of participants continued these trends or came closer to the norm. Bipolar disorder does not discriminate with regard to race, so we must look to social issues to explain the high proportion of white participants. On the other hand, bipolar disorder itself could explain why participants who were more educated had lower incomes and a higher unemployment rate.
STEP-BD is part of a recent trend in psychiatric research to have government-sponsored studies that enroll large numbers of "real-world patients," using few exclusion criteria, in order to make the findings more applicable to the typical psychiatrist's practice. STEP-BD has enormous potential to reveal more about bipolar disorder and, hopefully, to improve treatment guidelines. We will continue to report on the findings of this ambitious program.
References:
Kogan, J.N., et al. Demographic and diagnostic characteristics of the first 1000 patients enrolled in the Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD). Bipolar Disorders 6(2004): 460-9.
