"We believe that we need to help people with this illness develop a sound routine in order to help protect their biological clocks from disturbances. It's important to remember that while patients need to lead more regular lives, that doesn't mean they need to live boring lives," says Ellen Frank, Ph.D., professor of psychiatry and psychology at the University of Pittsburgh Medical Center's Western Psychiatric Institute and Clinic (WPIC) and co-author of one of the studies.
Bipolar disorder, also known as manic depression, is a mood disorder that affects more than 2 million Americans and may have a strong genetic link. It is characterized by swings in mood from severe depression to mania that may damage relationships at home and at work.
Focusing on social rhythm disruptions -- life events that disrupt an established routine and, potentially, sleep -- researchers from WPIC found 65 percent of bipolar patients with manic episodes experienced at least one social rhythm disruption event shortly before episode onset, compared to only 20 percent of the same subjects during an episode-free control period.
The WPIC researchers studied the life events of 39 people with bipolar illness for the eight weeks prior to their experiencing a manic or depressed episode and recorded routine-disrupting and psychologically stressful events. For a comparison group, they looked at the same participants during an eight-week period earlier in the same year that was not followed by a manic episode. The life events reported for both time periods were then rated for the degree of social rhythm disruption using a method developed at WPIC. A clear association between social rhythm disruption and onset of mania was found. Sleep reduction was the strongest common difference between those patients who became manic and those who did not.
These findings may help doctors develop new methods to treat patients with this destructive illness.
"Researchers have often associated stressful events with bipolar episodes," says Constance Hammen, Ph.D., professor of psychology and psychiatry and biobehavioral sciences at the University of California, Los Angeles, who will speak about how elevated levels of stress may contribute to bipolar episodes.
Dr. Hammen followed 52 patients for two years to determine if stress did indeed precipitate manic episodes. Her study confirmed the impact stress does play, and also found that patients who had a longer history with the illness were more vulnerable to the effects of stress. Personality characteristics like introversion and obsessionality also influenced whether stress induced relapses. While the WPIC researchers found that 65 percent of the bipolar patients who experienced a manic episode had a disruption in routine that could affect their regular sleep/wake cycle during the eight weeks prior to the onset of the episode, only 16 percent of the bipolar patients who became depressed had such an event during that time.
"For reasons we have yet to learn, people with bipolar disorder seem to have more delicate internal clock mechanisms," says Dr. Frank.
According to Dr. Frank, losing a single night of sleep for any reason may be enough to trigger mania. "Staying up all night to watch television, working into the wee hours to study or catch up on work or spending the night in the emergency room with a sick child may all act as a springboard into mania," she says. "The level of stress that causes the sleep loss doesn't seem to make much difference."
"The literature suggests that social rhythm disruption may play a role in the onset of depressive, as well as manic, bipolar episodes," says lead author Susan Malkoff-Schwartz, Ph.D., research principal and problem solving therapist at WPIC. "We suspect that social rhythm and/or sleep disruption may affect depressive onsets more gradually than manic onsets, and have begun looking into this."
Interest in maintaining social rhythms to help level out bipolar disorder's mood swings is leading researchers at the University of Colorado, Boulder to develop a new psychosocial treatment for bipolar disorder called Integrated Family and Individual Therapy (IFIT). IFIT involves the patient's family by helping them understand the vulnerabilities that bipolar patients have to even minor changes in their daily routines, says David Miklowitz, Ph.D., associate professor of psychology at the University of Colorado.
"Patients keep track of their regular social rhythms," Dr. Miklowitz explains. "Family members are taught to help keep the patient on a regular daily schedule, particularly during times when life events could disrupt their routines. They also learn to recognize the beginning signs of a recurrence in the patient, for example, sudden or gradual decreases in sleep, increases in irritability, and to learn to intervene -- usually by arranging emergency medical treatment for the patient -- before the episode spins out of control."
Future research may focus on how these findings can be applied to treatment and what effect other social rhythm disruptions, such as a sudden increase in sleep, have on various mental illnesses.