ETIOLOGY OF SUBSTANCE ABUSE

Etiology of Substance Abuse

Abstract

Substance use disorders are defined as the use of a substance that results in persistent and sometimes pervasive aversive consequences. Substance use disorders have profound economic and public health impacts in the United States. Researchers have identified important biological, psychological, and social factors that predict the development and resolution of substance use disorders. Biological processes related to substance use include physiological reactivity, changes, and adaptations. Psychological processes associated with substance use include conditioning, observational learning, beliefs about substance use, and emotions that cue substance use. Substance use disorders are thought by some to be chronic and progressive, but research on the natural course of these disorders disputes those beliefs.

Etiology of Substance Abuse

Introduction

Although the etiology of substance abuse is widely disputed, several theories have gained prominence. The moral, disease, and biological models contend that substance abuse results from individual factors, whereas social learning, systems, and sociocultural theories argue that social and cultural factors are the fundamental cause of substance abuse. More recently, a biopsychosocial approach has been suggested as a way to integrate elements from several of these theories into one unified approach.

There are significant economic costs associated with the abuse of alcohol and other substances. According to the Office of National Drug Control Policy, in 2002, the overall cost of abuse of substances other than alcohol in the United States approximated $181 billion. More than 20% of these costs were related to incarceration, and nearly another 20% were related to drug-related illnesses (DiClemente, 2003). Furthermore, the National Institute on Alcohol Abuse and Alcoholism estimated that, in 1998, the costs related to alcohol abuse alone were nearly $185 billion. The majority of these costs (about 66%) were related to lost current or future earnings due to alcohol-related illness or premature death.

Biopsychosocial Model

Researchers use a biopsychosocial model to understand addictive processes. Biological processes that have been identified include physiological reactivity to the ingestion of substances, physiological changes due to acute or chronic use of substances, and physiological adaptations to the level of exposure to the substances. Physiological reactivity occurs in response to the substance and results in metabolic changes in the body. Substances activate the pleasure-reward system in the brain, which often results in euphoria. Acute or chronic substance abuse can cause neurotoxicity and damage to vital organs. Commonly experienced cognitive impairments include difficulties with short-term and working memory; problems with executive cognitive functions related to decision making, problem solving, impulse control, and abstraction; and, in some cases, difficulties with balance and motor functions. Existing evidence suggests that some physiological changes are reversible, including cognitive impairment, after a period of abstinence (Donovan, Marlatt, 2005).

Psychological processes include behavioral, cognitive, and emotional responses to substance use. Behavioral processes operate according to learning principles. Classical conditioning in substance abuse occurs when particular stimuli are paired or associated with substance use. In substance abuse research, these stimuli are often referred to as cues or triggers. Substance use may occur at an automatic level when cues trigger substance use ...