Researchers are beginning to delve deeper into the causes of addiction and whether risk factors exist that make some people more susceptible than others. As a result, there is no denying that addiction starts in the brain.
There’s no one thing that causes addiction, rather there is typically a number of factors at play. However, one condition is standing out as a common precursor – mental health issues. This is no small issue given that one in four adults in the U.S. suffer from mental illness in any given year¹.
The Ties Between Mental Illness and Addiction
When two illnesses coexist it’s referred to as comorbidity². The fact that substance abuse and addiction are considered mental and/or behavioral health problems suggests that comorbidity between these and other mental health issues would be high, which is often the case.
Anatomically the two are related. Specific regions of the brain, particularly areas that regulate dopamine production, are impacted by both mental illness and addiction. Doctors have found that the portions of the brain that process stress and reward react to drug use and some mental disorders.
Another similarity between the two is that they are both considered developmental disorders³. Adverse events early in life, such as physical abuse or neglect, are often the cause of these types of disorders that advance over time.
During the early years of life, the brain is developing. Drug and alcohol use during this period can alter the brain in ways that make a person more susceptible to mental illnesses. The opposite is also true.
When both mental illness and substance abuse are present, it’s considered a dual diagnosis (4). Either of the conditions can be present first and lead to the other, or external factors can cause both to occur simultaneously. Roughly a third of people with a diagnosed mental illness also struggle with substance abuse. As many as 60% of people with an illicit drug addiction or substance abuse problem have a mental illness.
However, it should be noted that men are given a dual diagnosis more often than women. Other subgroups that are more likely to receive a dual diagnosis include:
- People with general health problems
- People from lower socioeconomic groups
- Military veterans
The Issue of Self-Medication
One of the primary reasons a person with a mental illness also suffers from addiction is self-medication. The person turns to drugs and alcohol as a way to cope with their mental distress. Few people realize that the introduction of drugs or alcohol only magnifies the mental illness.
This self-medication can also create additional problems that make mental illness worse. Guilt and regret over the substance abuse is a common problem. The use of drugs and alcohol can also harm personal relationships and fracture a person’s support system when they need it the most.
Genetic researchers have now identified connections between mental illness, addiction, and genes. Genetic factors can make some people predisposed to mental health problems and addiction, or they can make one more likely to occur after the other develops.
There are a number of environmental factors that can increase the likelihood of both mental disorders and substance abuse. These include:
- Sexual assault
- Physical abuse
- Exposure to drugs and alcohol at an early age
If a person with genetic vulnerabilities is exposed to these environmental factors, it significantly increases the risk of an addiction or mental illness developing.
Mental Illness Doesn’t Have to be Severe for Addiction to Manifest
A common misconception is that only severe mental illness is prominent enough to cause addiction problems. However, this simply isn’t the case. Even minor mental illnesses that are considered subclinical can cause a person to self-medicate with drugs or alcohol (5).
Take anxiety for example. To some people anxiety doesn’t seem severe, and it can be managed without medical intervention in mild cases. Yet, anxiety and mood disorders are known to overlap with substance abuse and addiction.
Some states have already recognized the need for simultaneous treatment. For example, in Florida residents have the Substance Abuse and Mental Health (SAMH) program (6), which can help people locate treatment facilities that address both problems.
The focus now is on identifying addiction and mental health problems as soon as possible in hopes of preventing a domino effect that leads to other disorders.