Additional information on alcohol-related disorders
Additional Information on Alcohol-Related Disorders
Associated Features and Disorders
Associated descriptive features and mental disorders.
Alcohol Dependence and Abuse are often associated with Dependence on, or Abuse of, other substances (e.g., cannabis; cocaine; heroin; amphetamines; the sedatives, hypnotics, and anxiolytics; and nicotine). Alcohol may be used to alleviate the unwanted effects of these other substances or to substitute for them when they are not available. Symptoms of depression, anxiety, and insomnia frequently accompany Alcohol Dependence and sometimes precede it. Alcohol Intoxication is sometimes associated with an amnesia for the events that occurred during the course of the intoxication ("blackouts"). This phenomenon may be related to the presence of a high blood alcohol level and, perhaps, to the rapidity with which this level is reached.
Alcohol-Related Disorders are associated with a significant increase in the risk of accidents, violence, and suicide. It is estimated that perhaps one in five intensive care unit admissions in some urban hospitals is related to alcohol and that 40% of people in the United States experience an alcohol-related accident at some time in their lives, with alcohol accounting for up to 55% of fatal driving events. Severe Alcohol Intoxication, especially in individuals with Antisocial Personality Disorder, is associated with the commission of criminal acts. For example, more than one-half of all murderers and their victims are believed to have been intoxicated with alcohol at the time of the murder. Severe Alcohol Intoxication also contributes to disinhibition and feelings of sadness and irritability, which contribute to suicide attempts and completed suicides. Alcohol-Related Disorders contribute to absenteeism from work, job-related accidents, and low employee productivity. Alcohol Abuse and Dependence, along with Abuse and Dependence of other substances, are prevalent among individuals across all levels of education and socioeconomic status. Rates of Alcohol-Related Disorders appear to be elevated in homeless individuals, perhaps reflecting a downward spiral in social and occupational functioning, although many people with Dependence or Abuse continue to maintain relationships with their families and function within their jobs. Mood Disorders, Anxiety Disorders, Schizophrenia, and Antisocial Personality Disorder may be associated with Alcohol Dependence. It should be noted that some evidence suggests that at least a part of the reported association between depression and Alcohol Dependence may be attributable to comorbid depressive symptoms resulting from the acute effects of intoxication or withdrawal.
Associated laboratory findings.
One sensitive laboratory indicator of heavy drinking is an elevation (>30 units) of gamma-glutamyltransferase (GGT). This finding may be the only laboratory abnormality. At least 70% of individuals with a high GGT level are persistent heavy drinkers (i.e., consuming eight or more drinks daily on a regular basis). A second test with comparable or even higher levels of sensitivity and specificity is carbohydrate deficient transferrin (CDT), with levels of 20 units or higher useful in identifying individuals who regularly consume eight or more drinks daily. Since both GGT and CDT levels return toward normal within days to weeks of stopping drinking, both state markers are useful in monitoring abstinence, especially when the clinician observes increases, rather than decreases, in these values over time. The combination of CDT and GGT may have even higher levels of sensitivity and specificity than either test used alone. Additional useful tests include the mean corpuscular volume (MCV), which may be elevated to high-normal values in individuals who drink heavily-a change that is due to the direct toxic effects of alcohol on erythropoiesis. Although the MCV can be used to help identify those who drink heavily, it is a poor method of monitoring abstinence because of the long half-life of red blood cells. Liver function tests (e.g., alanine aminotransferase [ALT] and alkaline phosphatase) can reveal liver injury that is a consequence of heavy drinking. Elevations of lipid levels in the blood (e.g., triglycerides and lipoprotein cholesterol) can be observed, resulting from decreases in gluconeogenesis associated with heavy drinking. High fat content in the blood also contributes to the development of fatty liver. High-normal levels of uric acid can occur with heavy drinking, but are relatively nonspecific. The most direct test available to measure alcohol consumption cross-sectionally is blood alcohol concentration, which can also be used to judge tolerance to alcohol. An individual with a concentration of 100 mg of ethanol per deciliter of blood who does not show signs of intoxication can be presumed to have acquired at least some degree of tolerance to alcohol. At 200 mg/dL, most nontolerant individuals demonstrate severe intoxication.
Associated physical examination findings and general medical conditions.
Repeated intake of high doses of alcohol can affect nearly every organ system, especially the gastrointestinal tract, cardiovascular system, and the central and peripheral nervous systems. Gastrointestinal effects include gastritis, stomach or duodenal ulcers, and, in about 15% of those who use alcohol heavily, liver cirrhosis and pancreatitis. There is also an increased rate of cancer of the esophagus, stomach, and other parts of the gastrointestinal tract. One of the most common associated general medical conditions is low-grade hypertension. Cardiomyopathy and other myopathies are less common, but occur at an increased rate among those who drink very heavily. These factors, along with marked increases in levels of triglycerides and low-density lipoprotein cholesterol, contribute to an elevated risk of heart disease. Peripheral neuropathy may be evidenced by muscular weakness, paresthesias, and decreased peripheral sensation. More persistent central nervous system effects include cognitive deficits, severe memory impairment, and degenerative changes in the cerebellum. These effects are related to the direct effects of alcohol or of trauma and to vitamin deficiencies (particularly of the B vitamins, including thiamine). One devastating central nervous system effect is the relatively rare Alcohol-Induced Persisting Amnestic Disorder (p. 177) (Wernicke-Korsakoff syndrome), in which the ability to encode new memory is severely impaired.
Many of the symptoms and physical findings associated with the Alcohol-Related Disorders are a consequence of the disease states noted above. Examples are the dyspepsia, nausea, and bloating that accompany gastritis and the hepatomegaly, esophageal varices, and hemorrhoids that accompany alcohol-induced changes in the liver. Other physical signs include tremor, unsteady gait, insomnia, and erectile dysfunction. Men with chronic Alcohol Dependence may exhibit decreased testicular size and feminizing effects associated with reduced testosterone levels. Repeated heavy drinking in women is associated with menstrual irregularities and, during pregnancy, with spontaneous abortion and fetal alcohol syndrome. Individuals with preexisting histories of epilepsy or severe head trauma are more likely to develop alcohol-related seizures. Alcohol Withdrawal may be associated with nausea, vomiting, gastritis, hematemesis, dry mouth, puffy blotchy complexion, and mild peripheral edema. Alcohol Intoxication may result in falls and accidents that may cause fractures, subdural hematomas, and other forms of brain trauma. Severe, repeated Alcohol Intoxication may also suppress immune mechanisms and predispose individuals to infections and increase the risk for cancers. Finally, unanticipated Alcohol Withdrawal in hospitalized patients for whom a diagnosis of Alcohol Dependence has been overlooked can add to the risks and costs of hospitalization and to time spent in the hospital.
Specific Culture, Age, and Gender Features
The cultural traditions surrounding the use of alcohol in family, religious, and social settings, especially during childhood, can affect both alcohol use patterns and the likelihood that alcohol problems will develop. Marked differences characterize the quantity, frequency, and patterning of alcohol consumption in the countries of the world. In most Asian cultures, the overall prevalence of Alcohol-Related Disorders may be relatively low, and the male-to-female ratio high. The low prevalence rates among Asians appear to relate to a deficiency, in perhaps 50% of Japanese, Chinese, and Korean individuals, of the form of aldehyde dehydrogenase that eliminates low levels of the first breakdown product of alcohol, acetaldehyde. When the estimated 10% of individuals who have a complete absence of the enzyme consume alcohol, they experience a flushed face and palpitations that can be so severe that many do not subsequently drink at all. Those 40% of the population with a relative deficiency of the enzyme experience less intense flushing but still have a significantly reduced risk of developing an Alcohol Use Disorder. In the United States, whites and African Americans have similar rates of Alcohol Abuse and Dependence. Latino males have somewhat higher rates, although prevalence is lower among Latino females than among females from other ethnic groups. Low educational level, unemployment, and lower socioeconomic status are associated with Alcohol-Related Disorders, although it is often difficult to separate cause from effect. Years of schooling may not be as important in determining risk as completing the immediate educational goal (i.e., those who drop out of high school or college have particularly high rates of Alcohol-Related Disorders).
Among adolescents, Conduct Disorder and repeated antisocial behavior often co-occur with Alcohol Abuse or Dependence and with other Substance-Related Disorders. Age-related physical changes in elderly persons result in increased brain susceptibility to the depressant effects of alcohol, decreased rates of liver metabolism of a variety of substances, including alcohol, and decreased percentages of body water. These changes can cause older people to develop more severe intoxication and subsequent problems at lower levels of consumption. Alcohol-related problems in older people are also especially likely to be associated with other medical complications.
Females tend to develop higher blood alcohol concentrations than males at a given dose of alcohol per kilogram because of their lower percentage of body water, higher percentage of body fat, and the fact that they tend to metabolize alcohol more slowly (in part because of lower levels of alcohol dehydrogenase in the mucosal lining of the stomach). Because of these higher alcohol levels, they may be at greater risk than males for some of the health-related consequences of heavy alcohol intake (in particular, liver damage). Alcohol Abuse and Dependence are more common in males than in females, with a male-to-female ratio as high as 5:1, but this ratio varies substantially depending on the age group. In general, females start to drink several years later than males, but once Alcohol Abuse or Dependence develops in females, the disorder appears to progress somewhat more rapidly. However, the clinical course of Alcohol Dependence in males and females is more similar than different.
Prevalence
Alcohol use is highly prevalent in most Western countries, with the 1994 per capita consumption in adults in the United States estimated at 2.17 gallons of absolute alcohol. Among adults in the United States, two-thirds to 90% have ever consumed alcohol, depending on the survey and the methods used, with figures for men higher than those for women. A 1996 national survey indicated that about 70% of men and 60% of women consumed alcohol, figures that varied with age, with the highest prevalence (77%) for those between ages 26 and 34 years. Higher proportions of drinkers were reported in urban and coastal areas of the United States, and there were only modest differences across racial groups. It should be noted that because these surveys measured patterns of use rather than disorders, it is not known how many of those in the surveys who used alcohol had symptoms that met criteria for Dependence or Abuse.
Perhaps reflecting differences in research methodology and changes in the diagnostic criteria over the years, estimates of the prevalence of Alcohol Abuse and Dependence have varied markedly across different studies. However, when DSM-III-R and DSM-IV criteria are used, it appears that in the mid-1990s, the lifetime risk for Alcohol Dependence was approximately 15% in the general population. The overall rate of current Alcohol Dependence (measured as individuals whose pattern of alcohol use fulfilled the criteria over the prior year) probably approached 5%.
Course
The first episode of Alcohol Intoxication is likely to occur in the mid-teens, with the age at onset of Alcohol Dependence peaking in the 20s to mid-30s. The large majority of those who develop Alcohol-Related Disorders do so by their late 30s. The first evidence of Withdrawal is not likely to appear until after many other aspects of Dependence have developed. Alcohol Abuse and Dependence have a variable course that is frequently characterized by periods of remission and relapse. A decision to stop drinking, often in response to a crisis, is likely to be followed by weeks or more of abstinence, which is often followed by limited periods of controlled or nonproblematic drinking. However, once alcohol intake resumes, it is highly likely that consumption will rapidly escalate and that severe problems will once again develop. Clinicians often have the erroneous impression that Alcohol Dependence and Abuse are intractable disorders based on the fact that those who present for treatment typically have a history of many years of severe alcohol-related problems. However, these most severe cases represent only a small proportion of individuals with Alcohol Dependence or Abuse, and the typical person with an Alcohol Use Disorder has a much more promising prognosis. Follow-up studies of more highly functioning individuals show a higher than 65% 1-year abstinence rate following treatment. Even among less functional and homeless individuals with Alcohol Dependence who complete a treatment program, as many as 60% are abstinent at 3 months, and 45% at 1 year. Some individuals (perhaps 20% or more) with Alcohol Dependence achieve long-term sobriety even without active treatment.
During even mild Alcohol Intoxication, different symptoms are likely to be observed at different time points. Early in the drinking period, when blood alcohol levels are rising, symptoms often include talkativeness, a sensation of well-being, and a bright, expansive mood. Later, especially when blood alcohol levels are falling, the individual is likely to become progressively more depressed, withdrawn, and cognitively impaired. At very high blood alcohol levels (e.g., 200-300 mg/dL), a nontolerant individual is likely to fall asleep and enter a first stage of anesthesia. Higher blood alcohol levels (e.g., in excess of 300-400 mg/dL) can cause inhibition of respiration and pulse and even death in nontolerant individuals. The duration of Intoxication depends on how much alcohol was consumed over what period of time. In general, the body is able to metabolize approximately one drink per hour, so that the blood alcohol level generally decreases at a rate of 15-20 mg/dL per hour. Signs and symptoms of intoxication are likely to be more intense when the blood alcohol level is rising than when it is falling.
Familial Pattern
Alcohol Dependence often has a familial pattern, and it is estimated that 40%-60% of the variance of risk is explained by genetic influences. The risk for Alcohol Dependence is three to four times higher in close relatives of people with Alcohol Dependence. Higher risk is associated with a greater number of affected relatives, closer genetic relationships, and the severity of the alcohol-related problems in the affected relative. Most studies have found a significantly higher risk for Alcohol Dependence in the monozygotic twin than in the dizygotic twin of a person with Alcohol Dependence. Adoption studies have revealed a three- to fourfold increase in risk for Alcohol Dependence in the children of individuals with Alcohol Dependence when these children were adopted away at birth and raised by adoptive parents who did not have this disorder. However, genetic factors explain only a part of the risk for Alcohol Dependence, with a significant part of the risk coming from environmental or interpersonal factors that may include cultural attitudes toward drinking and drunkenness, the availability of alcohol (including price), expectations of the effects of alcohol on mood and behavior, acquired personal experiences with alcohol, and stress.
Differential Diagnosis
For a general discussion of the differential diagnosis of Substance-Related Disorders, see p. 207. Alcohol-Induced Disorders may be characterized by symptoms (e.g., depressed mood) that resemble primary mental disorders (e.g., Major Depressive Disorder versus Alcohol-Induced Mood Disorder, With Depressive Features, With Onset During Intoxication). See p. 210 for a discussion of this differential diagnosis.
The incoordination and impaired judgment that are associated with Alcohol Intoxication can resemble the symptoms of certain general medical conditions (e.g., diabetic acidosis, cerebellar ataxias, and other neurological conditions such as multiple sclerosis). Similarly, the symptoms of Alcohol Withdrawal can also be mimicked by certain general medical conditions (e.g., hypoglycemia and diabetic ketoacidosis). Essential tremor, a disorder that frequently runs in families, may suggest the tremulousness associated with Alcohol Withdrawal.
Alcohol Intoxication (except for the smell of alcohol on the breath) closely resembles Sedative, Hypnotic, or Anxiolytic Intoxication. The presence of alcohol on the breath does not by itself exclude intoxications with other substances because multiple substances are not uncommonly used concurrently. Although intoxication at some time during their lives is likely to be a part of the history of most individuals who drink alcohol, when this phenomenon occurs regularly or causes impairment it is important to consider the possibility of a diagnosis of Alcohol Dependence or Alcohol Abuse. Sedative, Hypnotic, or Anxiolytic Withdrawal produces a syndrome very similar to that of Alcohol Withdrawal.
Alcohol Intoxication and Alcohol Withdrawal are distinguished from the other Alcohol-Induced Disorders (e.g., Alcohol-Induced Anxiety Disorder, With Onset During Withdrawal) because the symptoms in these latter disorders are in excess of those usually associated with Alcohol Intoxication or Alcohol Withdrawal and are severe enough to warrant independent clinical attention. Alcohol idiosyncratic intoxication, defined as marked behavioral change, usually aggressiveness, following the ingestion of a relatively small of amount of alcohol, was included in DSM-III-R. Because of limited support in the literature for the validity of this condition, it is no longer included as a separate diagnosis in DSM-IV. Such presentations would most likely be diagnosed as Alcohol Intoxication or Alcohol-Related Disorder Not Otherwise Specified.