Mood disorders and biological rhythms in young adults: A large population-based study

Clinical evaluation of biological rhythm domains in patients with major depression

“…Additionally, previous studies have considered disruptions of biological rhythm as a single symptom, or were conducted only in patients with bipolar disorder. 14,20,21,28,29 Only one recent study evaluated the effect of specific biological rhythm domains on unipolar depression, finding significant disruption in all biological rhythm domains (sleep, activity, social, and eating) and BRIAN-Total score both in patients with MDD and in those with bipolar disorder, compared to healthy controls. 21 However, this study was population-based, only included young adults (age 18-24 years), and did not take into consideration drug use or other confounders.…”

“…Studies using this instrument found that biological rhythm disturbances influence psychosocial functioning, 18 the severity of depression, 19 and quality of life 20 in patients with mood disorders. A recent study assessed the disruption of biological rhythm in a community sample of young adults with mood disorders (major depression and bipolar disorder), 21 while others were conducted including only patients with bipolar disorder. [18][19][20] However, there is a lack of research evaluating the relationship between severity of symptoms and domains of biological rhythm in patients with major depression.…”

Solar insolation in springtime influences age of onset of bipolar I disorder

“…Clinical symptoms that are frequently reported include sleep timing disturbances , irregular daily schedules , and an evening preference . These symptoms of circadian disruption may occur during episodes, while euthymic , and in those at high risk for bipolar disorder . Even small changes to circadian rhythms such as the shift to daylight savings time may have adverse mental health consequences .…”

Genetic polymorphisms associated with circadian rhythm dysregulation provide new perspectives on bipolar disorder

“…Sleep disorders are the most common manifestations of CR dysfunction and have been considered a marker trait of affective disorders. Individuals with BD and depression have been found to have higher rates of interruption of the biological rhythm when compared to healthy individuals, even after considering the influence of other variables such as sex, socioeconomic status, alcohol, tobacco, use of illicit drugs, anxiety disorder and psychotropic medication use . Also, workers who abruptly change their work shift may present with decreased cognitive functions and disturbance of mood and social and work activities, like those with affective disorders …”

“…Circadian disorders may increase, for instance, the prevalence of the metabolic syndrome in BD, possibly through disturbance of the levels of the hormones leptin and ghrelin . Changes in the chronotype can also alter inflammatory cytokine levels and oxidative stress levels in BD patients . Another important circadian marker analyzed in patients with BD is the hormone melatonin, produced by the pineal gland and considered the main endogenous regulator of rhythmic activities.…”