Chronobiology of depression
What are the circadian disturbances underlying depression vulnerability? How are they related to mood, cognition and sleep ?
- Niki Antypa
Depression is a common but heterogeneous disorder. Since the depression umbrella consists of different neurobiological subtypes, we need different approaches to advance knowledge and to develop tailored and more effective treatments. A promising, yet underdeveloped, approach is to focus on patients with circadian rhythm disturbances, e.g. problems in sleep-wake cycles, diurnal changes in mood, and/or disruptions in the endocrine system.
Circadian typology has been conceptualized in chronotypes: morning types, evening types and intermediate types. People that fall in each category prefer to perform physical and mental activities at the respective time of day.
We found that eveningness (late types) are associated with major depression in a large cohort study – The Netherlands study of Depression and anxiety.
We focused next on understanding the association between circadian types and depression, by exploring different psychological vulnerability factors of depression, such as cognitive reactivity and worry. We found that late types are more likely to ruminate, and this mediates the association with depression.
Further, in another study primarily in students, we currently explore chronotype effects on diurnal mood states, cognition and sleep through actigraphy.
The overall aim is to improve the current understanding of the pathophysiology underlying circadian imbalances in depression and to lead to new prospects of personalized, accelerated treatment in individuals with mood and sleep problems.