Disruption of the normal body clock rhythms is linked to increased chances of mood disorders, depression
Mood disorders such as bipolar and depression are linked to disruptions of the normal daily circadian rhythms.
Increased activity during rest periods and/or inactivity during the day are associated with a greater susceptibility to mood instability, loneliness, decreased happiness and satisfaction, and occasional cognitive decline. This increases the chances of severe depression and bipolar disorders in later life, according to a large observational study involving over 91,000 people, published in The Lancet Psychiatry.
‘Circadian rhythm’ also known as ‘biological clock’ is roughly a 24 hour cycle which regulates the sleeping and feeding patterns of all animals including human beings. It is affected by environmental factors like sunlight and temperature.
The 2017 Nobel Prize in Physiology or Medicine was awarded to Jeffrey C. Hall, Michael Rosbash, and Michael W. Young for discovering the mechanisms that control our biological clock
Sleeping at night and being awake during the day is an example of a light-related circadian rhythm. Circadian rhythms can influence sleep-wake cycles, hormone release, eating habits and digestion, body temperature, and other important bodily functions.
The 2017 Nobel Prize in Physiology or Medicine was awarded to Jeffrey C. Hall, Michael Rosbash, and Michael W. Young for discovering the mechanisms that control our biological clock. The fundamental discoveries of how the circadian clock regulates the daily cycles of human physiology have important implications for several diseases involving the brain, pancreas and stress disorders.
This observational study measured patterns of rest and activity (using accelerometers), and assessed the effect of circadian disruption on various mental health disorders.
The researchers analysed activity data in 91,105 participants (aged 37-73) from the UK Biobank general population cohort to obtain an objective measure of patterns of rest and activity rhythms, known as relative amplitude. All participants wore accelerometers for 7 days between 2013 and 2015 to record their activity. This information was linked to mental health questionnaires to assess symptoms of mental disorders and subjective wellbeing and cognitive function.
“Our findings indicate an association between altered daily circadian rhythms and mood disorders and wellbeing”, says author Dr Laura Lyall from the University of Glasgow, UK. “However, these are observational associations and cannot tell us whether mood disorders and reduced wellbeing cause disturbed rest-activity patterns, or whether disturbed circadian rhythmicity makes people vulnerable to mood disorders and poorer wellbeing.”