• Mental Health

Depression why does it happen?

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Depression why does it happen?

Waking up to another winter day with those festive holidays in the past, life can seem less pleasant than it should. Is this a normal feeling? Perhaps this is a more persistent feeling beyond the season. What could it mean?

This month we will look at being low in mood or depressed. Although this word may be loosely used, it is a defined medical condition. Further, there are many different types of depression – including one relating to winter.


Depression is estimated to affect 1/10 people at any time. However, this is probably an underestimation as many don’t report their symptoms, either from fear of judgement or discomfort of talking about negative feelings.

Depression affects women more and is higher amongst the elderly. The risk of depression is higher if other immediate family members have also suffered.


Depression means having a low mood. Whilst we all feel low sometimes dealing life’s challenges and frustrations, it becomes a medical concern when feelings extend beyond momentary sadness to persistent worthlessness, hopelessness, helplessness, anxiety and guilt.

When such feelings cause physical symptoms, it is even more suggestive of clinical depression. Associated symptoms can include affected sleep (unable to sleep, waking early), affected appetite/weight (eating too much or too little) and reduced energy and libido.

These feelings and symptoms then significantly affect life quality by negatively impacting work performance, family dynamics and social activity.


But why does it happen?

Biologically depression is linked to neurotransmitters in the brain- particularly serotonins, noradrenaline and dopamine. However, there is much debate as to their exact role and interaction with genes, childhood experiences and the environment in predisposing to depression. Whatever the basis, the final triggers are very common life events: work issues, relationship difficulties/breakups, family stress, financial concerns and bereavements.

Sometimes there are medical causes for depression such as long-term illnesses (cancer, heart disease, particularly diabetes), hormone disorders, brain damage (strokes, Parkinson’s, Multiple Sclerosis, dementia) and mental illnesses like Schizophrenia.

Some medications can also trigger low mood like benzodiazepines (used for anxiety and sleep) and steroids. Recreatiparticularalcohol, are also well associated with depression.


The most common form of depression is the straightforward form labelled as a major depressive episode. This involves the feelings and symptoms described earlier lasting most days for over two weeks.

However, there are other distinct forms.

Persistent: this involves symptoms to a lesser degree but carrying through a longer time period of over 2 years. It is also described as ‘dysthymia.’ Hopelessness feelings are a strong feature.

Bipolar: where major depression alternates with a type of elation called mania – the so-called ‘manic depressive.’ It requires treatment with special mood stabiliser medications.

Atypical: where there can be a normal mood for up to two months alternating between a mild form of elation and temporary major depression. This is also described as ‘cyclothymia.’

Situational: which is a reactive transient depression to a specific event. This is also called ‘adjustment disorder’.

It usually resolves without treatment.

Psychotic: an extreme form involving firm false beliefs (delusions) and imaginary voices/visions (hallucinations) relating to underlying feelings. It requires stronger treatment with antipsychotics and sometimes electroconvulsive therapy (ECT).

Seasonal: Also called ‘seasonal affective disorder’ (SAD) caused by lack of natural light. It occurs in winter of countries with short daylight hours. Treatment includes special light lamps.

Prenatal/Postnatal: this refers to the low mood in women who are due to deliver or who have recently delivered a baby. It is caused by a combination of the anxiety around having the baby but also the resulting real world life changes. It is treated in the same way as other types of depression.


Like many mental illnesses, depression is diagnosed through consultation with a doctor, with the focus on feelings and moods and behaviour. Of course, any potentially causative medications or diseases should be excluded before settling on depression as the cause.


There are two established ways to treat depression. Either or both in combination may be used, depending on the exact situation for each individual.

Psychological Therapies: ranging from counselling (finding new ways to think about problems), CBT (overcoming negative feelings in thought and behaviour) and psychoanalysis (finding hidden meanings in thoughts) to interpersonal therapy and guided self-help.

Antidepressants: affecting the brain neurotransmitters are used in more severe cases. They take weeks to work, can have significant side effects and require slow weaning. Types include SSRI’s (Fluoxetine, Sertraline, Ciptalopram), SNRI’s (Duloxetine, Venlafaxine), Atypical (Mirtazapine) and TCA’s (Amitryptaline).

So if you are feeling unusually low, please do not hesitate to see your doctor to discuss your feelings.

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