Although the specific causes of mental illnesses are not known, it is becoming clear over research that many of these illnesses are caused by a combination of psychological, biological, and environmental factors.
Biological Factors behind Mental Illness
Some mental illnesses are associated with abnormal functioning of nerve cell pathways or circuits that connect specific brain regions. Nerve cells within the brain pathways converse through chemicals called neurotransmitters. “Tweaking” these chemicals — through psychotherapy, medicines, or other medical procedures — can help pathways run more proficiently. In addition, weakness or injuries to certain regions of the brain have also been associated with some mental conditions.
Some other biological factors that contribute to these illnesses are the following:
Mental illnesses also run in families, signifying that individuals who have a family member with a mental illness may be to a greater extent at risk of developing them. Probability in families is passed on through genes. Specialists found that many mental illnesses are associated with abnormalities in some genes rather than just one or a few and how these genes respond to environmental factors are different for every individual (even identical twins). That is why an individual inherits a vulnerability to a mental illness and doesn’t certainly develop the illness. Mental illness itself arises from the combination of multiple genes and other factors — such as a traumatic event, abuse, or stress — which can affect, or trigger, a condition in an individual who has an inherited exposure to it.
Many infections are associated with damage to the brain in turn resulting in a mental illness or worsening of a previous illness. For example, a disorder known as pediatric autoimmune neuropsychiatric disorder developed because of the Streptococcus bacteria has been associated with the development of obsessive-compulsive disorder in children and other mental illnesses.
Brain defects or injury
Defects in or injuries to certain regions of the brain have also been associated with some mental illnesses.
Some evidence suggests that interference in the development of the early fetal brain or any trauma at the time of birth — for example, lack of oxygen in brain cells — may be a factor in the occurrence of certain illnesses, e.g. autism spectrum disorder.
Long-term substance abuse has also been linked to paranoia, depression, and anxiety.
Exposure to toxins such as lead plays a great role in developing mental illnesses. Poor nutrition also contributes to their development.
Psychological Factors behind Mental Illness
Psychological factors behind the development of mental illnesses include:
- Severe psychological trauma in childhood, such as sexual abuse, and physical or emotional disturbance.
- Big loss at in early age, such as the loss of a parent
- Reduced ability to relate to others
Environmental Factors behind Mental Illness
Some stressors can prompt an illness in an individual who is susceptible to any mental illness. These stressors include:
- Dysfunctional family life
- Feelings of insufficiency, low self-esteem, anger, loneliness, or anxiety
- Changing schools or jobs
- Death or divorce
- Cultural or social expectations
- Any type of substance abuse by the individual or his parents.
Substance use disorders and mental illnesses are closely associated as individuals addicted to drugs are at risk of developing anxiety and mood disorders two times higher as compared to non-addicts, and vice-versa.
Co-occurrence: A coincidence or more
The high prevalence of co-occurring drug use disorders and mental illnesses is not dependent on a causal association between these. Moreover, it does not specify any particular sequence at the start of the problem, simply because several factors may contribute to AMI and SUDs, and most of them are independent.
For example, it is essential to see if signs have progressed to a definite level (per DSM) to confirm the diagnosis of any mental illness. However, subclinical signs may also lead to substance use. Although it is always hard to tell which comes first between SUDs and AMI. However, three probabilities seem to exist.
Drug use may lead to mental illness
Drug or substance use may be the reason for causing one or more indications of a mental disorder in the user. The evidence associated with the possibility comes from the known connection between the high risk of marijuana and psychosis in some users.
Mental illness leading to drug use
Researchers have also been speaking about the potential role of mental illnesses leading to drug use. Individuals reporting subclinical, evident, or even mild mental illnesses are susceptible to substance use disorder as self-medication. Slowly, as the individual feels more enabled by the use of the substance, he/she becomes dependent on it, developing an addiction.
There are definite factors including brain deficits, genetic vulnerabilities, and/or early exposure to trauma or stress, which may cause both SUDs and AMI.
All these three states may express themselves in making a situation for a co-occurring SUD and AMI.
Exploring common factors
Genetics plays role in both, a SUD and an AMI. Genetic factors can be a noteworthy common connection between these two states, which is known to add to the development of both mental illnesses and addiction. According to scientists, genetics make a 40-60 percent impact on one’s susceptibility to addiction. At the same time, genes can also act incidentally contributing to the occurrence of SUD by altering the person’s response to anxiety or one’s affinity to develop novelty-seeking and risk-taking behaviors.
Similar brain regions are involved. It may be more than a concurrence that in the situation of both AMI and SUD, the same brain areas are affected. For example, any substance use disorder and mental illness such as anxiety and other psychiatric disorders affect the level of dopamine, a chemical that transmits impulses from neuron to neuron.
This correspondence of brain regions affected by SUDs and AMI may indicate a probability of some brain alterations that may result from any one of these, affecting the other.
Getting timely treatment
Different therapies have been proven effective in the treatment of comorbid conditions. However, it is essential to consider other linked factors like a person’s age and particular drug used among other stuff while going ahead with the scheduled treatment.