The link between depression and inflammation

According to some theories, inflammatory processes in the body favor the onset of depression.

Several studies have described the link between depression and inflammationThe link between depression and inflammation has been described in several studies, as many patients diagnosed with an inflammatory disease manifest depressive symptoms.

It is not that the idea that having inflammation will always lead to depression is advocated, but that both conditions have been found to have a high comorbidity, suggesting that they have a biological link in common.

Below we will talk about the theory that tries to explain this phenomenon, as well as delve into the biological causes behind this process.

The link between depression and inflammation

It has been seen that patients diagnosed with major depression are more prone to present inflammatory processes. In turn, people who suffer from chronic diseases, in which there is a chronic diseases, in which there is a high immune response, are more likely to be diagnosed with a mood disorder.are more likely to be diagnosed with a mood disorder.

Among the diseases in which inflammatory processes are present in which more relationship has been seen with depression we have, to say only a few, diabetes, rheumatoid arthritis, asthma, multiple sclerosis, cardiovascular problems, chronic pain and psoriasis.

Below we will look at the main theory that has tried to establish and explain the relationship between the two health problems.

Burning brain theory

This theory has been proposed to explain the relationship between depression, a mental disorder, and inflammation, a physiological process..

Several studies have shown that people who are diagnosed with major depression have higher levels of a factor involved in inflammatory processes, cytokines.

It appears that cytokines can alter the brain at the functional and structural level, thereby inducing changes in the brain.It seems that cytokines can alter the brain at the functional and structural level, thus inducing changes in both mood and cognitive abilities.

It has been suggested that inflammatory processes in Western societies are related to an unhealthy lifestyle, especially in relation to two factors: diet and environmental pollution.

Others, on the other hand, argue that the cause could be internal, caused by our way of reacting to stresses and strains. our way of reacting to environmental stressors, together with a style of thinking that induces worrying in an unhealthy way. that induces worrying in an unadaptive way, manifesting itself in physiological symptoms such as inflammation.

That is, we are so stressed and depressed that our body reacts physiologically, and that causes immune diseases to occur.

Stressful situations cause the body to release the stress hormone cortisol.. In turn, this hormone causes an increase in blood levels of cytokines, and substances that are related to wear and tear at the cellular level, such as nitric oxide.

Mechanisms that would be behind this link.

The organism, being healthy, reacts to external pathogens through immunological processes. In this way, it activates the cells responsible for defending the human body, preventing pathogens, whether they are viruses, bacteria or parasites, to run wild and achieve their goal: to make us sick.

However, However, the immune process in itself involves a certain amount of wear and tear and temporary discomfort. as the organism tries to cope with the external threat.

The inflammatory process is that response against the threat, and involves a certain involves a certain temporary discomfortThe inflammatory process is that response against the threat, and involves some temporary discomfort, such as when one has a fever or inflammation in a part of one's body.

The hypothesis behind the idea of the brain on fire is that social pressures, insecurities and any psychological problems can induce this same inflammatory response, as if they were viruses.

The problem with The problem with social pressures is that they are difficult to solve or diminish and, if the person copes with them in an unadaptive way, they subject their brain to constant stress. This causes psychopathology and organic problems to manifest.

Depression and inflammatory biomarkers

Cytokines, or cytokines, are proteins that are released during the inflammatory process, and serve to activate the immune system, stimulating it to cope with external threats..

As we have already seen, one of the inflammatory biomarkers, cytokines, are shown in higher amounts in people who are experiencing depression, which could be the biological link between inflammatory processes and mental health.

Cytokines and cognitive problems

Patients with depression have been shown to have, on average, greater cognitive problems compared to people without the diagnosis.

The problems are especially significant in areas such as attention, executive areas such as attention, executive functions, memory, as well as showing other cognitive deficits..

These problems have been found to correlate positively with higher levels of cytokines and also with the presence of other factors involved in the inflammatory process.

It appears that cytokines and other immunological factors may play a central role in synaptic plasticity and other cellular mechanisms involved in cognition.

This relationship between inflammation at the neurological level and cognitive dysfunctions has its evidences, especially if one takes into account a disease such as Parkinson's disease, Alzheimer's disease or mild cognitive impairment.

It is well known how beta-amyloid plaques, which are present in several dementias, affect function at the cognitive level and, together with cytokines, inflammatory processes are also implicated.

Thus, neuroinflammatory processes appear to lead to cognitive and behavioral changes through various mechanisms, including changes in gene expression and neuronal functioning.

Depression in patients with inflammatory diseases

Inflammation acquires a very important role in several metabolic, neurological and behavioral conditions.. No wonder it has been associated with depression. The following are several medical problems in which this immunological process is present and which can be related to depression.

Depression in diabetics

It has long been known that there is a relationship between depression and diabetes.

There is a high prevalence of people with insulin problems who manifest symptoms of depression; but, given that both depression and diabetes are related to depression.However, since both depression and diabetes are two very common conditions, some comorbidity is to be expected.

However, epidemiological studies have found that the two conditions occur together too often, which has suggested a relationship between sugar levels and diabetes. a relationship between sugar levels and the manifestation of depressive symptomatology..

It should be said that, while well-treated diabetes is not fatal, it is a chronic condition, which would cause the newly diagnosed person to go through depression for a while.

What has been seen is that high blood glucose levels is statistically associated with having a low mood..

In addition, the lifestyles of many depressed people and diabetics coincide. It is frequent that in both diagnoses, the profile of the person is that of someone who eats food rich in sugars and fats, as well as being sedentary.

Depression, rheumatoid Arthritis and multiple sclerosis

Depression seems to occur 5 to 10 times more often in people with a serious medical problem, such as arthritis or rheumatoid arthritis.such as arthritis or sclerosis, where the person becomes progressively weaker.

It has been seen that about half of the people who suffer from multiple sclerosis, either because of an inflammation-depression biological mechanism or because they are aware that their disease is chronic and neurodegenerative, are diagnosed with major depression.

In other diseases, also of inflammatory type, such as rheumatoid arthritis, psoriasis and gastrointestinal diseases such as Crohn's disease, the ratios range between 13 and 17% of cases with depression.

Conclusions

On the basis of the literature consulted, it appears that the link between depression and inflammation is a strong one.It is seen in multiple medical conditions in which there is immunological, metabolic, behavioral and cognitive involvement.

Depression occurs in a higher percentage in people who have been diagnosed with a disease in which there is endocrine involvement, such as diabetes, inflammatory diseases such as arthritis, sclerosis and gastrointestinal problems.

In any case, despite the relationship between both problems, it is worth understanding the idea that one will not necessarily generate the other. The reason why a person with a chronic illness has been diagnosed with depression may be because, after receiving the diagnosis of their medical problem, they have become depressed because of it, not as a symptom of the medical illness.

Bibliographic references:

• Amodeo, Giovanni & Trusso, Maria & Fagiolini, Andrea. (2017). Depression and Inflammation: Disentangling a Clear Yet Complex and Multifaceted Link. Neuropsychiatry. 07. 10.4172/Neuropsychiatry.1000236.
• Raison, Charles & Capuron, Lucile & Miller, Andrew. (2006). Raison CL, Capuron L, Miller AH. Cytokines sing the blues: Inflammation and the pathogenesis of depression. Trends Immunol 27: 24-31. Trends in immunology. 27. 24-31. 10.1016/j.it.2005.11.006.
• Dowlati Y, Herrmann N, Swardfager W, et al. A meta- analysis of cytokines in major depression. Biol. Psychiatry 67(5), 446-457 (2010).
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