Is addiction a disease?
1- Why is addiction considered a disease?
Addiction Medicine doctors view addictions as a chronic brain disease rather than a moral failure or lack of discipline. Just like how excess sugar can change the pancreas and lead to diabetes we say some substances/behaviors change the brain and lead to addiction.
We call it a disease because brain changes happen in a way that makes it extremely difficult to quit. The lower and more primitive part of the brain overpowers the higher more evolved thinking brain and the patient can’t stop even if they tried.
Although on the surface, most individuals and clinicians understand and relate to the disease model of addiction, I would argue that very few people truly grasp what this implies. This is understandable. I mean how is taking a drug or doing an action such as gambling a disease? Isn’t it a personal choice for someone to drink alcohol or gamble (insert whatever addiction here)? How could a personal choice be a disease? Shouldn’t the person have the discipline to stop?
It may be counterintuitive to think of addiction as a brain disease especially since societal norms have historically dictated that since an “addict” started taking the drug it is “the addict’s fault.” However, over the years, research has shown that this is an outdated way of thinking. It is now believed that 10-15% of the population has a brain that is vulnerable to dopamine surges which lead to out of control behaviors despite negative consequences known as addiction.
Throughout my writings and videos, I hope to give enough information to show why Addiction Medicine doctors think this way.
2- What leads to addiction?
There is a common misconception that one-time use of a drug will lead to addiction. Addiction typically develops and worsens over time in people who are susceptible to the disease of addiction (10-15% of the population). This is because over time drug use and addictive activities change the structure of the brain due to a process called neuroplasticity.
3- Why do brain changes occur?
A rewarding experience activates a region of the brain called the Ventral Tegmental Area (VTA). Once activated, the VTA then releases dopamine through a brain circuit called the mesolimbic pathway. This leads to an increase of dopamine in the Nucleus Accumbens. This increase in dopamine leads to long-term structural changes in the Nucleus Accumbens which leads to addiction.
Chronically high levels of dopamine from drug use lead to a cascade of cellular reactions that leads to the DNA changing what proteins it makes. Over time, the different proteins that are made will change the shape and structure of the brain making it more difficult for an addict to quit. For instance, in the Nucleus Accumbens, we see elevated dopamine causes the DNA to make more of the protein named FosB. Over time, this protein changes the shape of the Nucleus Accumbens and how this region of the brain works.
All drugs of abuse and addictive behaviors do this. This is why you may have heard that dopamine surges lead to addiction. However, this is an incomplete picture, Dopamine surges alone do not lead to addiction.
Brain Disease -Substance abuse
Addiction is now considered a disease because brain changes occur in a way that makes it extremely difficult for an individual to quit. To further illustrate this point let’s think of brain disease. In the general public, it is fairly common knowledge that a stroke may lead to brain damage leading to slurred speech, facial droop, weakness, etc. However, brain damage doesn’t only change how people move, brain damage may lead to how people behave and act. Some brain damage can even change an individual’s personality. For instance, some types of dementia affecting the frontal/temporal regions of the brain may lead to individuals acting rudely, insensitively, and less inhibited. People with this type of dementia may even start having pathological gambling. Just like how a stroke or dementia are diseases that change the structure of the brain and thus how people behave and act, addiction medicine physicians believe substance use disorders and behavioral addictions lead to a disease that affects the brain.
In summary, drug use changes who you are and how you behave. Remember that drug use and addictive behaviors change your brain and thus your behavior. The old adage you are what you eat is very applicable here.
4- In what ways does the brain change?
There are lots of ways of thinking about brain changes that happen. I like to think of addiction as affecting 4 big categories:
1- Motivation Circuitry
2- Anti Reward pathway
3- Interoception
4- Amygdala/hormones (neuroendocrine)
Other ways to think about what happens to the brain in addiction include the Stop-and-Go Model of addiction and the 3 stages of the cycle of addiction. I will be focusing on the 4 big categories mentioned above, however, may delve into the other ways of thinking to further explain things if needed.