In Brief

A balanced circadian rhythm—maintained through practical lifestyle habits, such as regular sleep patterns and consistent daily routines—may provide relief to the nearly 6 million American adults diagnosed with bipolar disorder.

In a study of 175 adults with the disorder, clinical psychologist Ellen Frank, PhD, found that patients who participated in a behavioral therapy designed to help them improve regularity in their daily routines averted new manic or depressive episodes longer than patients whose therapy focused just on regulating their mood symptoms and medication.

In the study, the clinicians treated the patients with bipolar disorder once a week until they achieved a stable remission of symptoms. One-half of patients were given interpersonal and social rhythm therapy, in which they used a monitoring device to track their sleep/wake cycles, meal times and physical activity. The other patients went through intensive clinical management, which offered them educational sessions on the disorder, medications and tips on basic sleep hygiene. All patients were also treated with medication-typically lithium-over the course of the 2.5-year study.

Frank found that the interpersonal and social rhythm therapy may ease the symptoms of bipolar disorder because it works to regulate the daily routines of these patients, who are often found to have more sensitive circadian clocks. Disruptions in sleep and routine may spur bouts of mania or depression, says Frank, a psychiatry and psychology professor at the University of Pittsburgh School of Medicine.

A related study by biologist Colleen McClung, PhD, further elucidated the relationship between the circadian system and bipolar disorder. McClung, a psychiatry professor at the University of Texas Southwest Medical Center, studied mice engineered to lack key circadian genes. She found that they behaved similarly to people in a manic state, exhibiting hyperactivity and shortened sleep cycles.

"The circadian system is fundamental to understanding the basic symptomatology of bipolar and unipolar disorders," says Frank.

--A. Novotney