Risk Factors and Causes of Substance Use Disorders

In this article, we’ll explore the causes of substance use disorders (SUD), as well as effective prevention and treatment options.

What is a Substance Use Disorder (SUD)?

Substance use disorders are influenced by a blend of genetic, environmental, and personal factors. Understanding the causes of substance use disorders is crucial for effective prevention and treatment.

Substance use disorders are a widespread epidemic, with over 20 million people having at least one SUD. Substance use disorders not only affect an individual’s health and well-being but also have significant social and economic impacts.1

Recognizing the nature of these disorders is key to developing targeted treatments and support systems that address the underlying issues and promote long-term recovery.

What Characterizes a Substance Use Disorder?

SUD is a complex medical condition. It involves a problematic pattern of use of substances like alcohol or other drugs. This problematic use causes significant impairment and distress in the individual’s life.

Key aspects of SUD include:1
  • A craving or strong urge to use the substance
  • Desire or failed attempts to reduce or control substance use
  • Using substances when it leads to failure in fulfilling major role obligations at work, school, or home
  • Using substances despite having persistent interpersonal problems caused or worsened by substance use
  • Using substances in situations where it is physically hazardous
  • Continuing to use substances despite knowing that it is causing or worsening physical or psychological problems
  • Needing more of the substance to achieve the desired effect or a diminished effect with continued use of the same amount (tolerance)
  • Experiencing withdrawal symptoms when decreasing or stopping use

SUD can affect almost every part of an individual’s life. It can lead to a range of serious health and social consequences. There is no exact way to determine the causes of substance use disorder, but there are many risk factors that contribute to its development.

Genetics and Causes of Substance Use Disorders

Genetics plays a significant role in the development of substance use disorders. Studies have estimated that genetics account for about 40% to 60% of the risk. The specific ways in which genetics contribute to the causes of substance use disorders can vary.2

Polygenic Nature

Polygenic means there is no single gene responsible for certain individual traits. These characteristics are made up of multiple genes. Thus, there is no single “addiction gene.” 3
Instead, the causes of substance use disorders are influenced by many genes in combination with one another. This polygenic nature makes it challenging to pinpoint specific genetic factors.4

Genetic Interactions with Environmental Factors

Understanding the risk factors and causes of SUD involves how genes and the environment interact. Some people may be more prone to addiction due to their genes and certain environmental factors, like stress or early substance exposure.5

Family Studies and Twin Studies

Studies of families and twins have provided evidence for the genetic causes of substance use disorders. For example, having a close relative with an addiction increases the risk. While twin studies have shown higher rates of SUD in identical twins compared to fraternal twins.6
Genetic predisposition is a significant factor in the risk of developing an SUD. But it is just one factor in a complex mix of genetics, environment, psychology, and society. It’s important to understand this interaction to develop effective treatment options.

Environmental Factors That Can Contribute to Substance Use Disorders

Environmental factors play a crucial role in the causes of substance use disorders. Certain factors, like genetics and personal traits, can increase the chance of developing an SUD.
Key environmental factors include:

Early Exposure to Substances

Childhood and adolescence is a critical period for brain development. Early exposure to drugs or alcohol during this time can increase the risk of developing an SUD. 

The developing brain is more susceptible to the chemical changes caused by substance use. This can lead to long-term changes in brain function and behavior.7

Peer Influence and Social Networks

Teenagers and young adults can easily be influenced by their peers to experiment with drugs or alcohol, which can lead to addiction. Being around friends who use substances can normalize use and allow for easier access.

Access to Drugs or Alcohol

Easy access to drugs or alcohol can increase the risk of experimentation and regular use. People living in places with easy access to drugs or in situations where drug use is common are more likely to develop substance use disorders.8

Stress and Trauma

Both stress and trauma may increase the risk and causes of substance use disorders. Ongoing stress can lead to substance use as a coping mechanism. Experiencing trauma, especially in childhood, has also been strongly linked to the development of SUD.9

Importance of Knowing and Understanding the Risks of SUD

To reduce the risk of developing an SUD, it’s important to understand the environmental effects. To address these factors, treatment must take a multi-faceted approach. This includes education, community support, policy changes, and counseling.

Adverse Childhood Experiences and Causes of Substance Use Disorders

Adverse childhood events (ACE) and trauma can impact an individual’s risk of developing an SUD. How these early experiences lead to addiction is complex.

Here is how ACE scores can relate to the causes of substance use disorders:

Increased Vulnerability to Stress

Traumatic experiences in childhood can alter brain development. The areas that can be affected by trauma are those involved in stress regulation, emotion processing, and executive functioning.10 This can cause greater stress and make it harder to control emotions, leading to increased substance use.

Emotional and Psychological Consequences

Childhood experiences like neglect or abuse can make it hard to form healthy relationships. This can lead to feelings of isolation and loneliness. Individuals may attempt to reduce these feelings through substance use.
Childhood trauma is also a known risk factor for various mental health disorders. Certain conditions can make it more likely for people to turn to substance abuse to self-medicate.

Impaired Cognitive Development and Coping Skills

Early trauma can impair cognitive functions such as attention, decision-making, and impulse control. This makes individuals more prone to risky behaviors, including substance use.

Individuals who experience childhood trauma may also find it difficult to develop healthy coping skills. As a result, they may turn to substance use to manage or escape from their emotions and memories.

To treat substance use disorders, programs must understand and strive to reduce the impact of early adverse experiences.

The Relationships Between Mental Health Conditions and Substance Use Disorders

Co-occurring substance use and mental health disorders are common. Almost 9.2 million adults in the U.S. have a co-occurring disorder.11

This relationship is complex and bidirectional. Mental health problems can raise the chance of developing an SUD, and substance use can cause mental health issues.

Here’s how mental health conditions are related to the causes of substance use disorders:

  • Self-medication hypothesis: Individuals with mental health conditions often turn to substances to self-medicate or ease their symptoms.
  • Shared vulnerability: Mental health disorders and SUD often have similar causes, like genetics, brain chemistry, and stress. This shared vulnerability can predispose individuals to both types of disorders.
  • Impaired judgment and coping skills: Mental health conditions can impair judgment and reduce effective coping skills. This can lead individuals to make choices that increase their risk of substance misuse.
  • Induction of new disorders: Chronic substance use can lead to the development of new mental health disorders. Excessive alcohol consumption can cause depression, while chronic stimulant use can lead to anxiety or psychosis.
  • Neurobiological changes: Using substances can change how the brain works, especially concerning rewards and stress. This can increase the vulnerability to mental health disorders.

An Interdisciplinary Approach

To reduce the risk of developing mental health conditions or an SUD, it’s crucial to understand their relationship. For treatment to be effective, it’s best to use approaches that address both substance use and mental health.

Neurobiological Causes of Substance Use Disorders

The development of an SUD involves complex neurobiological factors. These include:
  • Changes in brain structure
  • Neurotransmitter imbalances
  • Alterations in the brain’s reward pathway
Understanding these factors is crucial to understanding the nature of addiction.

Changes in Brain Structure

The prefrontal cortex is responsible for decision-making, impulse control, and executive functioning. Substance use can impair these functions. This can lead to increased impulsivity and poor decision-making related to substance use.12
Other areas of the brain that can be affected by substance use are the amygdala and limbic system. These areas are involved in emotional processing and stress response. Changes to these areas can cause stronger emotions and make people more sensitive to stress.
Using substances for a long time can change the brain’s circuits, called neuroplasticity. This can lead to different reactions and changes in how people think and act.

Neurotransmitter Imbalances

Most substances increase levels of dopamine in the brain’s reward system. This reinforces substance use by creating a sense of euphoria or pleasure.
Over time, the brain may produce less dopamine or reduce dopamine receptors. As a result, the person’s ability to enjoy activities decreases and they develop a dependence on the substance.13

Substances can also affect levels of other neurotransmitters like serotonin, GABA, and glutamate. These neurotransmitters play roles in mood regulation, anxiety, and excitability.

The Reward Pathway

The mesolimbic pathway, also known as the reward pathway, is a main target of addictive substances. This pathway is necessary for survival, like eating and being social.
However, it can be hijacked by substance use, leading to addictive behaviors.14 With repeated substance use, this reward system adapts, leading to tolerance and dependence.

How Do Social and Cultural Environments Influence the Causes of Substance Use Disorders?

The social and cultural environment significantly influences the causes of substance use disorders. Cultural factors, poverty, and access to education and healthcare play crucial roles in the development of an SUD. The way people feel about drugs and the help available to them are influenced by different factors.

Socioeconomic Disparities and Poverty

Lack of financial resources can limit access to healthcare and treatment for substance use disorders. Not having access to opportunities can lead to higher addiction rates.
Economic limitations also play a role in the causes of substance use disorders. People living in poverty often live in areas with more drug use and weaker deterrents against substance misuse.15

Cultural Factors

Cultural attitudes towards substance use impact behavior. In some cultures, moderate alcohol use might be socially accepted or even encouraged. In other cultures, it may be taboo.
Religious and moral beliefs can also influence substance use patterns. Some religions strictly prohibit substance use. This can lower the likelihood of developing an SUD among those who adhere to those beliefs.

Lack of Access to Education

Education plays a key role in SUD prevention. Lack of education can lead to a lack of awareness about the dangers of substance misuse and the benefits of healthy behaviors.
Education also provides better job opportunities and life prospects. These opportunities can reduce the likelihood of substance misuse as a response to life stressors.

Healthcare Access

When people don’t have easy access to healthcare, they might miss opportunities to prevent substance misuse. This limited access also means limited availability of treatment services for SUD.
The social and cultural surroundings affect the causes of substance use disorders among different groups of people. To address these concerns, treatment programs should include services in the community and education about addiction.

Do Personality Traits and External Factors Contribute to Substance Use Disorders?

Personality plays a role in all our decisions. Our personality drives our actions and interactions with others. Personality traits and individual characteristics influencing substance use might include impulsivity, sensation-seeking, and risk-taking behavior.

Similarly, external factors like stress may interact with features of our personality to increase the likelihood of substance misuse. For example, an individual who is impulsive and under stress may be more likely to use substances than an individual who has better emotional regulation.

Internal Influences

These characteristics interact with external factors to increase vulnerability to SUD. People who are impulsive and seek excitement are more likely to take risks. This could include experimenting with drugs or alcohol.

External Influences

External influences like peer pressure or stress can amplify this tendency by challenging coping skills. For example, if someone seeks out new experiences, they might be more likely to use drugs if their friends do it too.
These personality traits can make people more prone to being affected by drugs and alcohol. individuals are more at risk for developing an SUD due to a combination of personality traits and external environmental factors.

What Developmental Factors Contribute to the Causes of Substance Use Disorders?

Developmental factors play a role in developing an SUD. Each life stage contributes to the causes of substance use disorders in different ways. These will be detailed below.

Early Childhood

In early childhood, the quality of attachment and bonding plays a crucial role. A secure attachment to caregivers is essential for emotional regulation and social development.
But, when this attachment is insecure or disrupted, it can lead to difficulties in emotional regulation and an increased vulnerability to SUD.


During adolescence, the brain goes through major changes, especially in the parts that deal with risk and control. Those individuals who are inclined to take risks and have friends who use substances are more likely to experiment with drugs or alcohol.

Importance of Community Resources and Support During Adolescence

Educational and community influences are equally important during development. Positive school experiences and supportive environments can reduce the risk of substance use. However, academic struggles or bullying can increase vulnerability.
Having access to community resources can provide a protective buffer to the causes of substance use disorder.
These community resources might include:
  • Recreational activities
  • Mentorship programs
  • Substance use education

The Importance of Addressing Substance Use Early

Experiences in childhood to adolescence are important in determining the risk of developing an SUD. Changes in brain development and psychosocial maturation can influence risk. To create effective strategies for helping people with substance use disorders, it’s important to understand these factors.
Causes of Substance Use Disorders

Substance Use Disorder Treatment with Continuum Outpatient Center

What is Continuum Outpatient Center? We are a substance use and mental health program in San Antonio, Texas. Our team of experts is trained to provide you with the personalized care you need to recover successfully.
We understand that the road to recovery can be lonely and challenging. We provide a supportive and therapeutic environment for individuals seeking recovery. Here, you can find peer support as well as expert guidance to ensure you don’t face this journey alone.

What We Offer

Our team of experts provides individualized care by combining proven therapies with holistic wellness. We assist clients by providing counseling, therapy, and medical support. Clients learn coping skills, rebuild healthy relationships, and address trauma.
We are committed to treating the whole person, not just the addiction. This approach ensures that each client receives the tools and support necessary for a successful journey to wellness.

Start Your Journey Today

If you’re ready to regain control of your life, reach out to our team today. Contact us at 210.405.5935 or reach out online. We’re here to help you heal.

Questions About Treatment?
Reach out to our knowledgeable and compassionate Continuum Outpatient Center team for the guidance and support you need for sustainable recovery. We’re here to help you build a foundation for long-term happiness, wellness, and healing.