One of the best known and most common mental disorders in our society is depression. Although this mood disorder is widely known, generally little is said about its causes.
The reason for this is, among other things, that this disorder cannot be explained by a single factor: its onset and development are very complex processes. In this article we will talk about it and see, in a nutshell, what we know about the causes of depression.
What is depression?
Depression is an affective disorder through which pain and psychological distress are expressed. This includes both psychic and somatic symptoms, so to diagnose and apply appropriate treatment it is essential to assess the patient’s environment (family, work, emotional or marital state …).
Depression is an acute clinical disorder that affects the brain. Beyond feeling “hollow” or “sad” on certain days, you need to differentiate sadness from depression. The essential difference is that sadness is a natural response to a painful stimulus, this emotional expression of pain is a necessary response mechanism. However, if the sadness lasts over time, becoming chronic, without or with an apparent cause and with severe modularity, affecting the patient’s normal functioning in all areas of his daily life, then we speak of depression.
Depression is not a natural response but a pathology that can lead to disability. Epidemiological studies reveal that, for example, in the United States, 20% of the population suffers from this disease.
What are the causes of depression?
The main causes of depression are due to genetic factors (genetic predisposition) so it is very important to assess whether the patient has a family history.
Likewise, depressive conditions can also be due to physiological factors, as well as personal situation and environmental causes. We will explain each of these factors below.
1. Genetic factors
If there is a history of depression in the immediate family (parents and / or siblings), can increase the chances of suffering from this disease by 25% to 30%. There are studies of monozygotic twins (of a single zygote which divides into two after fertilization) which show that in one of the siblings the likelihood of suffering from depression increases up to 50% in the event of antecedents of others. However, the likelihood is significantly reduced in twins (dicygotic twins), up to 25% less.
As science advances in genetics, genes linked to the predisposition that an individual is more or less susceptible to depression have been found (Such as: SERT short serotonin transporter gene). It is estimated that up to 214 genes may be involved in the risk of depression.
2. Physiological factors
Depression is linked to a decrease in a neurotransmitter called serotonin, Specifically in dendrites which transmit impulses from the axon of one neuron to the soma of another. For this reason, psychiatrists sometimes use a group of drugs, selective serotonin reuptake inhibitors, the main function of which is to increase the predisposition to serotonergic levels in patients with depression, the most famous of which is certainly this which is marketed under the Prozac brand. the active ingredient is fluoxetine.
Other drugs such as anxiolytics acting on another neurotransmitter can also be used: GABA (γaminobutyric acid), anxiety is considered to be the sister of depression and are generally more or less linked according to the picture, anxiolytic drugs as the benzodiazepines are the most commonly prescribed.
Among the other causes are Endocrine disordersThese are another of the most common causes associated with depression, including diabetes and hyperthyroidism.
On the other hand, it has been observed that inflammatory processes affecting the brain greatly increase the chances of developing clinical depression. This means that a wide variety of issues in the body can affect mental health more or less indirectly, as there are many biological complications that end up causing inflammation.
3. Personal factors
It is proven that the prevalence of this disease is significantly higher in women, especially during pregnancy and postpartum (DPP) due to hormonal variations.
Postpartum depression (PPD) is defined as a transient disorder that begins two to four days after childbirth and resolves spontaneously over a period of two weeks. There are two types of PPD, babyblues depression and depressive disorder itself.
In medicine it is called babyblues a slight alteration in mother’s mood, accompanied by mild depressive symptoms. It is manifested by a lack of concentration, anxiety, sadness, but above all by an instability of mood with a great tendency to cry. It does not require treatment because it goes away spontaneously in a short time.
however, in the case of PDP, symptoms appear at 12 weeks and present a more acute picturePsychological and physical symptoms may arise, for example in the first case there may be feelings of worthlessness, suicidal ideation or thoughts related to death, and in the case of physical symptoms these may include headaches and intestinal discomfort, among others. In this case, if medical treatment is required.
Age is also a determining factor. The period between 35 and 45 years is the highest incidence of this disease. Although depression should also be highlighted in minors, mainly during the period of puberty and adolescence, an age when we undergo very significant hormonal changes while psychologically defining ourselves as people. In the case of depressive behaviors in childhood, more attention should be paid as it can have a very different manifestation than adults and is sometimes camouflaged under other types of disorders, but it is extremely important to wear a special attention to the area. familiar.
4. Environmental factors
They are considered to be environmental causes all those external stimuli that influence the person and that can act as catalysts for depression.
Negative, family and / or work situations can cause stress and trigger depression, especially if the person has a history of alcohol dependence or drug use. Poor relationships with others, along with difficulty communicating and isolation are key factors that increase the likelihood that a person will develop a pattern of depression.
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