Social Rhythm Disruption Research Articles

Life events and affective disorders.

To summarize research in life events and affective disorders Review of the literature. Many studies have shown that episodes of unipolar depression are preceded by life events at higher rates than in control samples. A variety of stressful events are involved with only limited specificity but some relationship to social exit events. Life events also affect remission and relapse of depression. Effects of life events are less when the disorder has already been recurrent, particularly where illness is severe. Effects of life events are also weaker in bipolar disorder than unipolar, but major life events may be important in first onset. Recent evidence suggests a specific role of social rhythm disruption events in manic relapses. Causative chains are multifactorial and complex, and genetic factors can influence life event exposure.

Which depressions are related to life stress?

This paper examines the relationship of recent life events to specific kinds of depression using published studies and the author's own work. An overall effect of life events on depression has been found consistently and is moderate in degree. In suicide attempts there are stronger and more immediate effects than in depression. Life events precede both non-melancholic and melancholic depressions. It is only in recurrent depressions that life events are less common with melancholic pictures. Life events influence bipolar disorder as well as unipolar. Mania may be preceded by life events, particularly those involving social rhythm disruption, but it is harder to rule out events which are consequences of insidious development of illness. There are strong effects of life events and social support in postpartum depressions but in postpartum psychoses these effects are absent. Events precede depression comorbid with other disorders as well as pure depression. The course of depression is also influenced by life stress with less remission where negative events occur after onset and better outcome where earlier adverse events are neutralized. Relapse is related to immediately preceding life events. However, where depressions are both severe and recurrent life stress effects weaken and as the number of episodes increases preceding life events lessen. These findings suggest that some kinds of depression are more related to psychosocial causation and some are more biological in origin.

Stress and affective disorders in humans.

A consistent body of findings published over 30 years shows raised rates of life events before onset of clinical unipolar depression. A range of threatening events is implicated, with only limited specificity, although a somewhat closer relationship to interpersonal losses. Social support both buffers effects of life events and its absence also has some independent stressful effects. Life stress also affects outcome. Effects extend across the age range, but are weaker or absent in recurrent disorder, particularly when this is severe or melancholic. They are also weaker in bipolar disorder, where social rhythm disruption may have a particular effect. The causative contribution of life stress is of moderate size overall but does not exclude many other factors. Causative chains are complex and life stress itself is not fully independent, because available social support is shaped by personal capacity to form relationships, and occurrence of life events has some genetic elements and is predicted by disturbance in childhood.

Social rhythm disruption and stressful life events in the onset of bipolar and unipolar episodes.

An association between social rhythm disruption (SRD) and onset of manic episodes has recently been observed. Whether other types of bipolar (depressive and cycling) or unipolar depressive episodes are similarly related to SRD is unclear, as is the association between severely threatening life events and onset of bipolar manic, depressed and cycling episodes. Bipolar patients with purely manic (N= 21), purely depressed (N = 21) and cycling (N = 24) episodes, and 44 patients with recurrent unipolar depression, were interviewed with the Bedford College Life Events and Difficulties Schedule. The presence of severe and SRD events during the year prior to index episode onset was then determined. More manic than cycling and unipolar subjects experienced SRD events during 8- and 20-week pre-onset periods, and severe events during 20-week pre-onset periods. Controlling for age and prior number of episodes left most findings unchanged. An earlier finding of more manic subjects with SRD events in an 8-week pre-onset versus control period was also replicated. It appears that manic onsets are influenced by stressful life events, especially those involving SRD, in a unique manner compared to onsets of other types of bipolar and unipolar episodes. Onset of bipolar cycling episodes, in contrast, seems to be relatively unaffected by SRD or severe life events. These findings refine the hypothesis that SRD may precipitate onset of affective episodes to be specific to manic onsets.

Stressful life events and social rhythm disruption in the onset of manic and depressive bipolar episodes: a preliminary investigation.

The association between stressful life events and onset of bipolar episodes is unclear. The association between bipolar episode onset and types of life events that disrupt social routines, and potentially sleep, has not yet been investigated. Thirty-nine bipolar patients with primarily manic (n = 20) or depressed (n = 19) index episodes were interviewed with the Bedford College Life Event and Difficulty Schedule to determine the presence of severe events during 8-week pre-onset and control periods. All life events were also rated for degree of social rhythm disruption (SRD). More bipolar subjects experienced at least 1 SRD event and severe event in the pre-onset vs control periods. When subjects were divided into those with manic or depressive onsets, the only significant pre-onset vs control difference was for manic patients with SRD events. Additionally, the proportion of subjects with a pre-onset SRD event was greater for manic than for depressed patients. We found evidence that life events characterized by SRDs routines are associated with the onset of manic, but not depressive, episodes. Severe events seem to be related to onset of bipolar episodes, although it remains unclear whether severe events relate differentially to depressive and manic onsets.