Defining Substance Use Disorder

Substance use disorder combines the previous DSM-IV-TR categories of "substance abuse" and "substance dependence" into a single disorder, measured on a diagnostic continuum from mild to severe. Each specific substance is addressed as a separate use disorder, such as alcohol or stimulants. Other substances include opioids, sedatives, cocaine, cannabis, amphetamines, inhalants, and nicotine.

Addiction is the continued repetition of a behavior despite adverse consequences, or a neurological impairment leading to such behaviors. Addictions can include, but are not limited to, substance abuse, exercise addiction, food addiction, sexual addiction, computer addiction and gambling. Classic hallmarks of addiction include impaired control over substances or behavior, preoccupation with substance or behavior, continued use despite consequences, and denial. Habits and patterns associated with addiction are typically characterized by immediate gratification (short-term reward), coupled with delayed deleterious effects (long-term costs).

Physiological dependence occurs when the body has to adjust to the substance by incorporating the substance into its 'normal' functioning. This state creates the conditions of tolerance and withdrawal. Tolerance is the process by which the body continually adapts to the substance and requires increasingly larger amounts to achieve the original effects. Withdrawal refers to physical and psychological symptoms experienced when reducing or discontinuing a substance that the body has become dependent on. Symptoms of withdrawal generally include but are not limited to anxiety, irritability, intense cravings for the substance, nausea, hallucinations, headaches, cold sweats, and tremors. Chemical and hormonal imbalances may arise. Physiological and psychological stress is to be expected if the substance is not re-introduced.

Substance Use, Addiction, and Effects

Individuals suffering from substance use disorder and addiction may engage in the use of many substances. This can lead to personal problems such as failing health and unemployment, and interpersonal problems such as broken families and alienation.

Epidemiology

Substance-related disorders, a category which includes both substance dependence and substance abuse, can lead to significant personal, interpersonal, and societal problems. These disorders are most prevalent in individuals aged 18–25, with a higher occurrence in men than women, and higher occurrence in urban residents than rural residents. On average, general medical facilities hold 20% of patients with substance-related disorders, which could possibly lead to psychiatric disorders later on. Over 50% of individuals with substance-related disorders will often have a dual diagnosis, where they are simultaneously diagnosed with another psychiatric diagnosis, the most common being major depression, dysthymia, personality disorders, and anxiety disorders. 

Most countries have legislation which makes various drugs and drug-like substances illegal. Although the legislation may be justifiable on moral grounds to some, it can make addiction or dependency a much more serious issue for the individual. Reliable supplies of a drug become difficult to secure as illegally produced substances may have contaminants. Withdrawal from the substances or associated contaminants can cause additional health issues, and the individual becomes vulnerable to both criminal abuse and legal punishment. 

DSM-5 Diagnostic Criteria

The diagnostic criteria for substance use disorder in DSM-5 is set at two or more criteria from a list of 11. Severity of the substance use disorders is based on the number of criteria endorsed, where 2-3 endorsements indicate a mild disorder, 4-5 indicate a moderate disorder, and 6 or more indicate severe substance use disorder. Substance use disorder can be diagnosed with physiological dependence, evidence of tolerance or withdrawal, or without physiological dependence.  In addition, criteria for cannabis and caffeine withdrawal were added. 

Defining Gambling Disorder

Problem gambling or gambling addiction is an urge to continuously gamble despite harmful negative consequences or a desire to stop. Severe problem gambling may be diagnosed as clinical pathological gambling if the gambler meets certain criteria and is associated with both social and family costs. 

DSM-5 Diagnostic Criteria

The DSM-5 has re-classified the condition as an addictive disorder, with sufferers exhibiting many similarities to those who have substance addictions. In order to be diagnosed, an individual must have at least four of the following symptoms in a 12-month period:

• Needs to gamble with increasing amounts of money in order to achieve the desired excitement.
• Is restless or irritable when attempting to cut down or stop gambling.
• Has made repeated unsuccessful efforts to control, cut back, or stop gambling.
• Is often preoccupied with gambling (e.g., having persistent thoughts of reliving past gambling experiences, planning the next venture, thinking of ways to get money with which to gamble).
• Often gambles when feeling distressed (e.g., helpless, guilty, anxious, depressed).
• After losing money gambling, often returns another day to get even (“chasing” one’s losses).
• Lies to conceal the extent of involvement with gambling.
• Has jeopardized or lost a significant relationship, job, or educational or career opportunity because of gambling.
• Relies on others to provide money to relieve desperate financial situations caused by gambling.

Etiology

Several theories of substance use and addiction exist, some of the main ones being genetic predisposition, the self-medication theory, a psychological predisposition, and factors involved with social/economic development. It has long been established that genetic factors along with social and psychological factors are contributors to substance use and addiction. Epidemiological studies estimate that genetic factors account for 40–60% of the risk factors for alcoholism. Similar rates of heritability for other types of drug addiction have been indicated by other studies. Genetic factors may create a predisposition for substance abuse, which means that an individual may have a tendency toward substance abuse. The self-medication hypothesis suggests that certain individuals abuse drugs in an attempt to self-medicate physical, psychological problems, or social problems. There are strong associations between poverty and addiction. 

Understanding how learning and behavior work in the reward circuit of the brain can help in understanding drug-seeking behavior and addiction. Drug addiction is characterized by strong, drug-seeking behaviors in which the person who is addicted persistently craves and seeks out drugs, despite the knowledge of harmful consequences. Addictive drugs produce a reward, which is the euphoric feeling resulting from sustained dopamine concentrations in the synaptic cleft of neurons in the brain. The reward circuit, also referred to as the mesolimbic system, is characterized by the interaction of several areas of the brain.

According to the Illinois Institute for Addiction Recovery, evidence indicates that pathological gambling is an addiction similar to chemical addiction. It has been seen that some pathological gamblers have lower levels of norepinephrine than normal gamblers. According to a study conducted by Alec Roy, formerly at the National Institute on Alcohol Abuse and Alcoholism, norepinephrine is secreted under stress, arousal, or thrill, so pathological gamblers gamble to make up for their under-dosage. Deficiencies in serotonin might also contribute to compulsive behavior, including a gambling addiction. Others argue that social factors are far more important determinants of gambling behavior than brain chemicals and suggest that a social model may be more useful in understanding the issue.

Treatment 

Early treatment of acute withdrawal from substances often includes medical detoxification, in which a person goes through the process and experience of withdrawal symptoms while discontinuing a drug. A detoxification program for physical dependence does not necessarily address the precedents of addiction, social factors, psychological addiction, or the often-complex behavioral issues that intermingle with addiction. 

Treatments for addiction usually involve planning for specific ways to avoid the addictive stimulus and/or therapeutic interventions intended to help a client learn healthier ways to find satisfaction. Clinical leaders in recent years have attempted to tailor intervention approaches to specific influences that affect addictive behavior, using therapeutic interviews in an effort to discover factors that led a person to embrace unhealthy, addictive sources of pleasure or relief from pain. Several evidenced-based intervention programs have emerged, including behavioral marital therapy, community reinforcement approaches, cue exposure therapy, and contingency management strategies. Most treatment for addictions involves counseling, step-based programs, self-help, peer-support, medication, or a combination of these. 

Twelve-step programs (such as Alcoholics Anonymous) are a set of guiding principles, sometimes accepted by members as being 'spiritual principles', outlining a course of action for tackling problems of addiction including alcoholism, drug addiction, and compulsion. Alcoholics Anonymous is the largest of all the twelve-step programs (from which all other twelve-steps programs are derived), followed by Narcotics Anonymous