Since 2000, the National Household Survey on Drug Abuse (NHSDA) has included a series of questions to assess dependence on and abuse of substances, as well as questions asking whether respondents had received treatment for a problem related to substance abuse. The dependence and abuse questions are designed to measure dependence and abuse based on the criteria specified in the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) (American Psychiatric Association [APA], 1994). The questions on dependence ask about health, emotional problems, attempts to cut down on use, tolerance, withdrawal, and other symptoms associated with substances used. The questions on abuse ask about problems at work, home, and school; problems with family or friends; physical danger; and trouble with the law due to substances used. Dependence reflects a more severe substance problem than abuse, and persons are classified with abuse of a particular substance only if they are not dependent on that substance. This chapter provides estimates of the prevalence and patterns of dependence and abuse on illicit drugs and alcohol in the Nation from the 2001 NHSDA. It also provides estimates of the prevalence and patterns of the receipt of treatment for problems related to substance use. A third section of this chapter discusses the need for and receipt of treatment specifically for problems associated with illicit drug use.
Because of changes in 2000 in the NHSDA questionnaire and the definitions employed for determining treatment need, the estimates presented in this chapter are not comparable with NHSDA estimates of dependence, abuse, treatment, or treatment need produced from the 1999 and earlier NHSDAs. However, because the questions and definitions employed for determining treatment need were the same in 2000 and 2001, the estimates in this chapter are comparable with estimates from the 2000 NHSDA. Trends in the estimates of dependence, abuse, treatment, and treatment need between 2000 and 2001 are discussed in this chapter.
7.1 Substance Dependence and Abuse
Overall, an estimated 16.6 million Americans aged 12 or older in 2001 were classified with dependence on or abuse of either alcohol or illicit drugs (7.3 percent of the total population). Of these, 2.4 million were classified with dependence on or abuse of both alcohol and illicit drugs, 3.2 million were dependent on or abused illicit drugs but not alcohol, and 11.0 million were dependent on or abused alcohol but not illicit drugs (Figure 7.1).
Of the 16.6 million persons with substance dependence or abuse in 2001, about half (8.2 million) were substance dependent. Of these, 0.9 million were classified with dependence on both alcohol and illicit drugs, 4.5 million were classified with dependence on alcohol but not illicit drugs, and 2.7 million were classified with dependence on illicit drugs but not alcohol.
The number of persons with substance dependence or abuse increased from 14.5 million (6.5 percent of the population) in 2000 to 16.6 million (7.3 percent) in 2001 (Figure 7.1).
Among the 5.6 million Americans classified with dependence on or abuse of illicit drugs, there were 3.5 million Americans classified with dependence on or abuse of marijuana (1.5 percent of the total population and 62.0 percent of those classified with dependence on or abuse of illicit drugs).
Among past year users of heroin in 2001, 50.0 percent (0.2 million were classified with dependence on or abuse of heroin. Among users of cocaine, 24.9 percent (1.0 million) were classified with dependence on or abuse of cocaine. Among past year users of marijuana, 16.5 percent (3.5 million) were classified with dependence on or abuse of marijuana. Among past year users of pain relievers, 11.8 percent (1.0 million) were classified with dependence on or abuse of pain relievers.
There were 13.4 million persons classified with dependence on or abuse of alcohol (5.9 percent of the total population). Among past year users of alcohol, 9.3 percent were classified with alcohol dependence or abuse.
The percentage of the population with dependence on or abuse of illicit drugs increased from 2000 to 2001 (1.9 to 2.5 percent). There were significant increases from 2000 to 2001 in the rates for illicit drug abuse (0.7 to 0.9 percent) as well in the rates for illicit drug dependence (1.2 to 1.6 percent). There were significant increases in the percentage of the population with dependence on or abuse of marijuana and hashish (1.3 to 1.5 percent) and the percentage of the population with dependence on or abuse of pain relievers (0.3 to 0.4 percent).
The percentage of the population with dependence on or abuse of alcohol also increased from 2000 to 2001 (5.4 to 5.9 percent). There was a significant increase from 2000 to 2001 in the rate for alcohol abuse (3.1 to 3.5 percent) but not in the rate for alcohol dependence (2.3 to 2.4 percent).
Age at First Use
Adults who first used drugs at a younger age are more likely to be classified with dependence on or abuse of drugs than adults who initiated use at a later age. Among those who first tried marijuana at age 14 or younger, 11.8 percent were classified with dependence on or abuse of an illicit drug in the past year compared with only 2.1 percent of adults who had first used marijuana at age 18 or older. This pattern of higher rates of dependence or abuse among persons initiating their use of marijuana at younger ages was observed by demographic subgroups, as well as separately for rates of dependence and rates of abuse (Figure 7.2). A similar pattern was observed for age at first use of alcohol and dependence on or abuse of alcohol among adults.
Age
Rates for illicit drug or alcohol dependence or abuse show substantial variation by age. The rate for illicit drug or alcohol dependence or abuse was 0.9 percent at age 12, and rates increased with age until the highest rate (22.8 percent) was reached at age 21. After age 21, the rates declined with age. The rate for persons aged 26 or older was 5.4 percent; the rate for persons aged 18 to 25 was 18.4 percent; and the rate for youths aged 12 to 17 was 7.8 percent.
There were statistically significant increases in the rates of illicit drug or alcohol dependence or abuse from 2000 to 2001 among persons aged 18 to 25 (15.4 to 18.4 percent) and among persons aged 26 or older (4.8 to 5.4 percent). For youths aged 12 to 17, rates were similar in 2000 and 2001 (7.7 and 7.8 percent) (Figure 7.3).
Gender
Males are twice as likely to be classified with dependence on or abuse of illicit drugs or alcohol as females. Among males, 10.0 percent were classified with illicit drug or alcohol dependence or abuse, while 4.9 percent of females were classified with illicit drug or alcohol dependence or abuse (Figure 7.4).
Among youths aged 12 to 17 in 2001, however, the rate of illicit drug or alcohol dependence or abuse among females (8.0 percent) was similar to the rate among males (7.6 percent) (Figure 7.4).
Between 2000 and 2001, the rate of illicit drug or alcohol dependence or abuse increased among males aged 12 or older (from 8.9 to 10.0 percent) and among females aged 12 or older (from 4.2 to 4.9 percent).
Race/Ethnicity
Among persons aged 12 or older in 2001, the rates for illicit drug or alcohol dependence or abuse were highest among American Indians/Alaska Natives (13.9 percent) and among persons reporting more than one race (12.6 percent). Asians and Native Hawaiians or other Pacific Islanders had the lowest rates for illicit drug or alcohol dependence or abuse (3.7 and 4.9 percent, respectively). Among whites, the rate was 7.5 percent, among blacks, 6.2 percent, and among Hispanics, 7.8 percent.
Between 2000 and 2001, there were increases in the rates of illicit drug or alcohol dependence or abuse for most racial/ethnic groups, but the increase was statistically significant only among whites (from 6.6 to 7.5 percent).
Education/Employment
Illicit drug or alcohol dependence or abuse is associated with educational status. Among adults aged 18 or older in 2001, those who had not completed high school had the highest rate of illicit drug or alcohol dependence or abuse (8.2 percent), while college graduates had the lowest rate of illicit drug or alcohol dependence or abuse (6.1 percent). This association is due primarily to the strong association between illicit drug dependence or abuse with education (3.7 percent for adults with less than a high school education vs. 0.9 percent for college graduates). There is no clear association between education and alcohol dependence or abuse.
Rates of illicit drug or alcohol dependence or abuse are associated with current employment status. An estimated 15.4 percent of unemployed adults 18 or older in 2001 were classified with dependence on or abuse of illicit drugs or alcohol, while 7.9 percent of full-time employed adults were classified as such.
Most adults with substance dependence or abuse are employed either full or part time. Among the 14.7 million adults with dependence or abuse, 11.3 million (77 percent) were employed.
Geographic Area
Rates of illicit drug or alcohol dependence or abuse among persons aged 12 or older varied by geographic division in 2001. The lowest rate of illicit drug or alcohol dependence or abuse was observed in the East South Central division (6.0 percent), and the highest rate was in the New England division (9.1 percent).
In 2001, the rate for illicit drug or alcohol dependence or abuse was lowest in less urbanized nonmetropolitan counties (6.0 percent) and highest in small metropolitan counties and urbanized nonmetropolitan counties (7.7 percent) (Figure 7.5).
Among youths aged 12 to 17 in 2001, the rate of illicit drug or alcohol dependence or abuse was highest for completely rural counties (11.0 percent) and lowest for counties in large metropolitan areas (7.4 percent) and counties in metropolitan areas with a population between 250,000 and 1 million (7.4 percent).
7.2 Treatment for a Substance Use Problem
Estimates described in this section refer to treatment received to reduce or stop drug or alcohol use, or for medical problems associated with the use of drugs or alcohol. This includes treatment received in the past year at any location, such as in a hospital, at a rehabilitation facility (outpatient or inpatient), mental health center, emergency room, private doctor's office, self-help group, or prison/jail. The definition of treatment in this section is different from the definition of treatment used in measuring the drug abuse treatment gap, which is described in Section 7.3 and excludes treatment at an emergency room, private doctor's office, self-help group, prison or jail, or at a hospital as an outpatient.
An estimated 3.1 million people aged 12 or older (1.4 percent of the population) received some kind of treatment for a problem related to the use of alcohol or illicit drugs in the 12 months prior to being interviewed in 2001. Of these, 1.2 million received treatment for both alcohol and illicit drugs, 0.5 million received treatment for illicit drugs but not alcohol, and 1.0 million received treatment for alcohol but not illicit drugs. (Estimates by substance do not add to the total because the total includes persons who reported receiving treatment but did not report which substance the treatment was for.)
Between 2000 and 2001, there was no statistically significant change in the number of persons aged 12 or older receiving treatment for alcohol or illicit drugs (2.8 to 3.1 million persons). There was also no significant change in the number receiving treatment for alcohol (2.1 to 2.2 million persons). However, between 2000 and 2001, the number receiving treatment for illicit drugs increased significantly from 1.3 million (0.6 percent) to 1.7 million (0.8 percent).
Among persons aged 12 or older in 2001, males were more likely than females to receive treatment for an alcohol or illicit drug problem in the past year (1.9 vs. 0.9 percent). Among youths aged 12 to 17, the percentage of males who received treatment for an alcohol or illicit drug problem was 1.8 percent, and the percentage of females who received treatment was 1.3 percent.
Among persons aged 12 or older in 2001, the rate of alcohol or illicit drug treatment during the 12 months prior to the interview was highest among American Indians/Alaska Natives (4.4 percent) and persons reporting more than one race (3.1 percent) and lowest among Asians (0.4 percent).
The rate of alcohol or illicit drug treatment among persons aged 12 or older in 2001 was higher in metropolitan areas (1.5 percent) than in nonmetropolitan areas (1.0 percent).
Among the 3.1 million persons aged 12 or older who received treatment for alcohol or illicit drugs in the past year, 1.6 million received treatment at a self-help group (Figure 7.6). There were 1.2 million people who received treatment at a rehabilitation facility as an outpatient, 869,000 who received treatment at a rehabilitation facility as an inpatient, 727,000 at a mental health center as an outpatient, 709,000 as a hospital inpatient, 437,000 at a private doctor's office, 384,000 at an emergency room, and 176,000 at a prison or jail. (Note that the estimates of treatment by location include persons reporting more than one location.)
Among the 3.1 million persons who received treatment for alcohol or drugs in the past year, nearly 2.0 million received treatment for alcohol during their most recent treatment (Figure 7.7). An estimated 852,000 persons received treatment for marijuana, and 554,000 persons received treatment for cocaine. (Note that the estimates of treatment by substance include persons reporting for more than one substance.)
7.3 Needing and Receiving Treatment for an Illicit Drug Problem
This section addresses the need for and receipt of treatment for an illicit drug problem. It includes estimates of the drug abuse "treatment gap," which is defined as those persons who needed treatment for an illicit drug problem in the past year but did not receive treatment. An individual is defined as needing treatment if he or she is dependent on or has abused an illicit drug or received treatment for an illicit drug problem at a "specialty" substance abuse facility in the past 12 months. "Specialty" substance abuse facilities include drug and alcohol rehabilitation facilities (inpatient or outpatient), hospitals (inpatient only), and mental health centers.
Between 2000 and 2001, there was a significant increase in the estimated number of persons aged 12 or older needing treatment for an illicit drug problem. The number of persons needing treatment increased from 4.7 million people (2.1 percent of the total population) to 6.1 million people (2.7 percent of the population) (Figure 7.8). Between 2000 and 2001, there also was a significant increase in the number of people receiving treatment for an illicit drug problem at a specialty facility. The number increased from 0.8 million people (16.6 percent of the people who needed treatment) to 1.1 million people (17.3 percent of the people who needed treatment).
The drug abuse treatment gap was estimated to be 5.0 million people in 2001, or 2.2 percent of the total population aged 12 or older, compared with 3.9 million (1.7 percent) in 2000.
Of the 5.0 million people who needed but did not receive treatment in 2001, an estimated 377,000 reported that they felt they needed treatment for their drug problem. This includes an estimated 101,000 who reported that they made an effort but were unable to get treatment and 276,000 who reported making no effort to get treatment.
Age
For youths aged 12 to 17, an estimated 1.1 million persons (4.9 percent of this population) needed treatment for an illicit drug abuse problem in 2001. Of this group, only 0.1 million people (10.2 percent of youths aged 12 to 17 who needed treatment) received treatment, leaving an estimated treatment gap for youths of 1.0 million.
For youths, there was no statistically significant change from 2000 to 2001 in the estimated number who needed and received treatment for an illicit drug abuse problem.
Gender
Among persons aged 12 or older in 2001, the percentage of males needing treatment for an illicit drug problem was higher than the percentage of females needing treatment (3.5 vs. 1.9 percent). On the other hand, the percentage receiving specialty treatment among those needing treatment was higher for females than males (21.8 vs. 14.6 percent).
Among youths aged 12 to 17 in 2001, the percentage of males needing treatment for an illicit drug problem was almost equal to the percentage of females needing treatment (4.9 vs. 4.8 percent). The percentage receiving specialty treatment among youths needing treatment was higher for males than females (11.4 vs. 8.8 percent). This is not a statistically significant difference.
Race/Ethnicity
In 2001, 2.6 percent of whites aged 12 or older needed treatment for an illicit drug problem. Among these whites needing treatment, 15.0 percent received treatment at a specialty facility. Among blacks, 3.1 percent needed treatment for an illicit drug problem, and among Hispanics 3.3 percent needed treatment. Among blacks needing treatment, 28.7 percent received treatment, but among Hispanics needing treatment, only 15.9 percent received treatment.
Geographic Area
Similar to rates for illicit drug dependence or abuse, the rate needing treatment among persons aged 12 or older was lowest in the West North Central division (1.8 percent) and highest in the Pacific division (4.0 percent) in 2001.
The percentage of persons needing treatment for an illicit drug problem in 2001 was higher in large metropolitan counties (2.9 percent) than in nonmetropolitan counties (2.2 percent).
This page was last updated on June 16, 2008.
SAMHSA, an agency in the Department of Health and Human Services, is the Federal
Government's lead agency for improving the quality and availability of
substance abuse prevention, addiction treatment, and mental health
services in the United States.
