The term stress is not a useful objective term to be used as a description of a scientific phenomenon that can be studied. It can neither be defined in objective terms nor can it be measured. It is impossible to objectively measure the amount of stress individuals experience in the same situation because the experience of stress is totally subjective. This results in much of the research involving stress relying on self-report measures of stress from research subjects. Self-report measures are notoriously unreliable.
The endocrinologist Hans Seyle is responsible for many of the common notions of the term stress. Seyle defined stress as a nonspecific response to demands for change. His definition and understanding of how the stress response works is still cited in many texts today despite information indicating that it is probably an insufficient account of what stress is and how it affects the body and mind.
Seyle found that animals exposed to prolonged stressors were more vulnerable to developing different types of diseases. Researchers following up on his ideas suggested that individuals exposed to prolonged periods of stress were also vulnerable to developing certain physical conditions like ulcers and psychological issues like depression.
It is generally accepted that experiencing high levels of stress, such as experiencing a traumatic event or being exposed to prolonged periods of stress, is a risk factor for the development of nearly every psychological disorder, including substance use disorders. However, stress can also be result of prolonged exposure to what many would consider positive events, such as planning for a wedding, buying a new house, or adjusting to new living conditions, and therefore defining exactly what constitutes stress, how to measure stress, and how stress affects different people remains a bit of a conundrum. For example, it is estimated that nearly 50 percent of the population in the United States experiences a severe traumatic or stressful event; however, a very small proportion of the population develops post-traumatic stress disorder (less than 10 percent) and few also develop any type of substance use disorders (less than 20 percent of the entire population). Thus, it is inaccurate to say that even experiencing severe levels of stress directly causes substance use disorders, as there are obviously other interacting factors that must be present in these associations.
Stress and Substance Abuse
Instead of being a direct causal mechanism for the development of substance use disorders, the experience of either intense or prolonged levels of stress are best described as risk factors for the development of substance use disorders. According to the World Health Organization, a risk factor is a situation or condition that increases the probability that one will develop a specific type of illness or condition. Either having the risk factor or not having the risk factor cannot guarantee that one will or will not develop some disorder, illness, or other condition; it is only associated with an increased probability that one will develop something.
Stress is also a nonspecific risk factor in that individuals exposed to the same types of stressful conditions may develop a number of different issues or conditions. Other nonspecific risk factors for the development of psychiatric disorders include being abused as a child, experiencing some other form of traumatic event, and having a first-degree relative who is diagnosed with some type of mental health disorder. Individuals who develop substance use disorders most likely have a number of interacting risk factors that contribute to their issues. It is very difficult to generalize which types of risk factors are most likely to result in specific disorders; however, it is known that experiencing high levels of stress or prolonged stress is associated with a number of issues.
The key in these findings is the term higher rates of substance abuse. Not individuals who experience extreme stress develop issues, and certainly developing a substance use disorder is not exclusive to people who have experienced stressful events. The mechanisms by which stress and substance use disorders are related are not well understood. It is known that both severe stressful events and chronic exposure to stress result in neurobiological changes and that chronic substance abuse also results in neurobiological changes. There are a number of hypotheses as to how these factors interact:
- The very popular self-medication hypothesis suggests that individuals who experience chronic levels of stress or extreme stressful events use drugs and alcohol to help them deal with the unpleasant experience of stress. While there is some validity to this notion, it should also be noted that a small proportion of individuals who admit to using drugs and alcohol to cope with stressful experiences develop substance use disorders. In individuals who develop substance use disorders, their substance abuse does not wax and wane in accordance with their stressful experiences. Thus, while some individuals may self-medicate with drugs and alcohol, this explanation cannot be used as an overall causal explanation for the relationship between stress and substance abuse. Research suggests that this may happen, but as an overall explanation, it falls short of explaining the relationship.
- It is also observed that individuals with all types of psychological disorders have higher rates of substance abuse and report higher levels of stress than individuals who are not diagnosed with these disorders. One explanation is that individuals who are prone to developing any type of psychological disorder are also more vulnerable to developing substance use disorders due to a number of shared risk factors, such as similar neurobiological pathways, genetic associations, environmental experiences, etc. Thus, individuals prone to the development of any form of mental illness are also more vulnerable to the development of substance abuse.
- An individual’s style of interpreting the world and events appears to have a profound influence on their experience of perceived stressors and their vulnerability to developing substance use disorders or other mental health disorders. Individuals who generally view their experiences and actions as being within their sphere of control, and their feelings and attitudes as being subject to change, are less likely to suffer ill effects from stress and to develop substance use disorders. These types of attitudes and perceptions are largely learned, and they are also based on experience. Thus, belief systems and attitudes can be changed and altered for the better or worse. Part of the saliency of stress as a potential contributor to the development of substance use disorders or any other mental health disorder is dependent on individual perceptions regarding control over their reactions to the events in their lives. Individuals who perceive they have more control will tend to experience stressful events as less threatening and less stressful. These individuals should be at decreased risk to develop substance use disorders as well. The research supports this notion.
Treatment for trauma and stress-based disorders often includes an element of cognitive restructuring from therapies, such as Cognitive Behavioral Therapy and mindfulness therapy. These cognitive restructuring techniques allow the individual to more objectively assess their responses to stressful events, objectively confront and cope with issues related to anxiety and fear, and learn to control their responses to perceived stress. When individuals have a better developed sense of control over themselves and their reactions to environmental stressors, they tend to perceive stressful events as less threatening. Likewise, these individuals are less apt to develop issues with substance use disorders.
There is an obvious relationship between the experience of stress and the development of substance use disorders; however, the relationship between these entities is very complicated. Specific predictions are difficult to make regarding what types of stressors will lead to the development of substance abuse.
The experience of stress is highly subjective in nature, and there can be no claim that stress causes the development of a substance use disorder. Because stress is a risk factor for the development of substance use disorders and its perception is based on subjective interpretations, assisting vulnerable individuals who are exposed to stressful events to learn stress management techniques should reduce their risk for the development of substance use disorders.