Low Self-Esteem, Guilt & Hopelessness
Lack of self-confidence, feelings of guilt and a bleak vision of what the future holds are trademark symptoms of clinical depression.
Fatigue
Fatigue is a commonly occurring symptom in patients of depression, according to a 2004 study published in Psychiatry.
Serotonin is the neurotransmitter emitted by our brain responsible for creating feelings of happiness. Similarly, epinephrine is the neurotransmitter responsible for creating energy.
Biologically, clinical depression suppresses the levels of serotonin produced by the brain, which in turn triggers a lower production of other neurotransmitters, including epinephrine. This results in chronic fatigue.
Out of 78,463 respondents of the Depression Research in European Society study conducted in six European countries, 73 percent reported tiredness as a major symptom of depression, according to a 2000 study published in European Neuropsychopharmacology.
A patient of depression will feel physically tired even after an adequate night’s sleep and without much physical activity. This will cause mental tiredness as well, rendering the patient incapable of engaging in any activity.
Diagnosis and treatment of fatigue in patients of depression is poor, which leads to more severe and longer-persisting depression, according to a 2014 study published in Depression and Anxiety.
Insomnia
The homeostasis process of your body tells you when you have been awake long enough and require sleep. The circadian process of your body maintains the sleepiness and wakefulness during the day.
Depression messes up these twin systems that help you sleep.
Out of 531 patients of depression, 97 percent reported insomnia, out of whom 59 percent reported that lack of sleep severely undermined the quality of their lives, 40 percent admitted to daytime napping and 34 percent said insomnia was “very distressing”, according to a 2009 study published in International Journal of Psychiatry in Clinical Practice.
Moreover, non-depressed insomniacs present a two-fold risk of developing depression as opposed to people with no sleep problems, according to a 2011 study published in the Journal of Affective Disorders.
Lastly, insomnia that persists after depression increases the risk of becoming clinically depressed once again, according to a 2000 study published in Sleep Medicine Reviews. It is important to consider this possibility when seeking treatment for depression.
Anger & Irritability
Along with a prolonged, obvious and overwhelming sense of despair, there is one other emotion that is characteristic of the initial stage of depression – anger.
This is often accompanied with heightened irritability and a tendency to lose one’s cool over seemingly trivial things.
Any tiny and harmless thing can trigger an outburst from a depressed person, and they will not shy away from lashing out at family, friends and even strangers.
A depressed individual, even when they are not verbally expressing rage, might be consumed with anger internally.
Moreover, a depressive condition that is accompanied by anger is more severe in intensity than regular clinical depression and is likely to stay longer too, according to a 2013 study published in the Journal of the American Medical Association.
Such a serious, prolonged and rage-infested depression can also trigger other disorders, such as substance abuse and anxiety disorders, the study further notes.