Journal of Psychiatry

Genetic Correlations Differences in Biological Rhythms of Major Psychological Disorders Subtypes

Duah Dwomoh^* Department of Psychiatry, University of Stuttgart, Keplerstrasse, Stuttgart, Germany
^*Correspondence: Duah Dwomoh, Department of Psychiatry, University of Stuttgart, Keplerstrasse, Stuttgart, Germany, Email:

Received: 01-Jul-2022, Manuscript No. JOP-22-17490; Editor assigned: 04-Jul-2022, Pre QC No. JOP-22-17490(PQ); Reviewed: 18-Jul-2022, QC No. JOP-22-17490; Revised: 25-Jul-2022, Manuscript No. JOP-22-17490(R); Published: 01-Aug-2022, DOI: 10.35248/2378-5756.22.25.518

About the Study

Bipolar Disorder (BIP) and Major Depression (MD) are both widespread, frequently chronic conditions that can be harmful to both the individuals who have them and the people around them. Depressive episodes are a key characteristic of MD, whereas manic (BIP-I) or hypomanic (BIP-II) episodes are a key characteristic of BIP and typically occur in between depressive episodes. Bipolar Disorder Types I and II (BIP-II) and Major Depressive Disorder (MDD) are mood disorders characterised by the recurrence of depressive, manic, and hypomanic episodes during which particular alterations in activity level, circadian rhythm, and sleep are noticed. Although it is well recognised that genetic variables have a role in the variety of both mood disorders and these biological cycles, it is unclear to what extent their underlying genetics overlap.

Typically, different biological rhythms are seen throughout various mood episodes (depressed, manic, hypomanic). Constant sorrow and/or loss of interest in practically all activities are the characteristic symptoms of a depressive episode. Additional symptoms include feelings of guilt or worthlessness, suicidality, lack of focus, weight loss, fatigue, sleep difficulties, and changes in psychomotor function. An uncontrollably high or irritated mood persists during manic episodes and hypomanic episodes (which are less severe). Additional signs include having a disproportionately high perception of one's own importance or grandiosity, being more talkative and easily distracted, having a decreased need for sleep, having a substantially higher level of energy and activity, and/or having psychomotor agitation.

Actigraphy studies show that patients with MD exhibit less activity than healthy controls. The same is true for those who have BIP. Comparing the distinct mood states (depressed, manic, and hypomanic) within BIP, manic and hypomanic phases show much higher levels of activity than depressive phases. Actigraphy studies, however, examine several different types of activity, such as "sedentary behaviour" or "moderate activity," in addition to overall physical activity levels. A person in good health is active during the day and less so at night (high relative amplitude), but people with mood disorders may show the reverse pattern (low relative amplitude), which denotes a disruption in the circadian rhythm. Both depression and BIP are associated with lower relative amplitudes when compared to healthy people.

A natural biological activity that occurs repeatedly, sleep provides a plethora of vital bodily purposes. Daytime sleepiness, which is also known to be more prevalent in patients with MD and BIP, is widely described in MD and BIP, along with sleep issues, insufficient sleep, irregular sleep-wake cycles, and abnormalities in sleep length. Heritability estimates for Mood Disorders (MD) are 40% and for biological rhythms (BIP) are 80%. For biological rhythms, these estimates are heterogeneous, ranging from small (30%) to high (78%) for physical activity, from 40%-54% for chronotype, and from 31%-49% for normal sleep due to factors like age variation.

The genetic relationships between BIP-I and BIP-II were shown to be positive for moderate activity and negative for sedentary behaviour, suggesting that both BIP-I and BIP-II have genetic characteristics associated with increased physical activity. Our results are consistent with earlier research indicating a positive genetic connection between BIP and walking and moderate activity based on a previous BIP GWAS. In order to put the current findings into perspective, it should be recalled that past studies were based on BIP GWAS that combined all subtypes and found that the vast majority of patients had BIP-I. Mood disorders sometimes involve symptoms like poor sleep duration and frequent awakenings. According to genetic research, MD and BIP share a substantial genetic overlap with traits related to sleep, such as insomnia, chronotype, and sleep length.