Substance Dependence, Abuse and Treatment

2. Dependence on and/or Abuse of Illicit Drugs and Alcohol

2.1 Overview

2.1.1 Dependence on and/or Abuse

• Overall, an estimated 14.5 million Americans aged 12 or older in 2000 were classified with dependence on or abuse of either alcohol or illicit drugs (6.5 percent of the total population). Of these, 1.9 million were classified with dependence on or abuse of both alcohol and illicit drugs (0.9 percent of the population). An estimated 2.4 million Americans were dependent on or abused illicit drugs but not alcohol (1.1 percent of the total population). An estimated 10.2 million Americans were dependent on or abused alcohol but not illicit drugs (4.6 percent of the population) (Figure 1).

• Among the 4.3 million Americans classified with dependence on or abuse of illicit drugs (1.9 percent of the total population), 1.5 million were classified with only abuse of illicit drugs (35.7 percent of those classified with dependence on or abuse of illicit drugs).

• There were 2.8 million Americans classified with dependence on or abuse of marijuana (1.3 percent of the total population and 66.0 percent of those classified with dependence on or abuse of illicit drugs). Of these, 1.2 million Americans were classified with only marijuana abuse (41 percent of those classified with abuse of or dependence on marijuana).

• Among past year users of heroin, 60.1 percent (0.2 million) were classified with dependence on or abuse of heroin. Among users of cocaine, 22.5 percent (0.7 million) were classified with dependence on or abuse of cocaine. Among past year users of marijuana, 15.3 percent (2.8 million) were classified with dependence on or abuse of marijuana. Among past year users of pain relievers, 11.2 percent (0.7 million) were classified with dependence or abuse.

• There were 12.1 million persons classified with dependence on or abuse of alcohol (5.4 percent of the total population). Of these, 7.0 million were classified with only abuse of alcohol (58.0 percent of those with abuse or dependence). Among past year users of alcohol, 8.8 percent were classified with alcohol dependence or abuse.

• Adults who first used drugs at a younger age were 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, 10.2 percent were classified with dependence on or abuse of an illicit drug in the past year compared with only 2.0 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 2).

• A similar pattern was observed for alcohol dependence or abuse among adults. Among those who first tried alcohol at age 14 or younger, 13.4 percent were classified with dependence on or abuse of alcohol in the past year compared with only 3.1 percent of adults who had first used alcohol at age 18 or older. This pattern also was similar by sociodemographic subgroups and for abuse of or dependence on alcohol (Figure 3).

Figure 1 Past Year Substance Dependence or Abuse among Persons Aged 12 or Older: 2000

Note: Dependence is based on the definition found in the 4^th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (APA, 1994). "Illicit drug" refers to marijuana/hashish, cocaine (including crack), inhalants, hallucinogens (including LSD and PCP), heroin, or any prescription-type psychotherapeutic used nonmedically.

Source: SAMHSA, Office of Applied Studies, National Household Survey on Drug Abuse, 2000.

Figure 2 Past Year Illicit Drug Dependence or Abuse among Adults, by Age at First Use of Marijuana: 2000

Note: Dependence is based on the definition found in the 4^th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (APA, 1994). "Illicit drug" refers to marijuana/hashish, cocaine (including crack), inhalants, hallucinogens (including LSD and PCP), heroin, or any prescription-type psychotherapeutic used nonmedically.

Source: SAMHSA, Office of Applied Studies, National Household Survey on Drug Abuse, 2000.

Figure 3 Past Year Alcohol Dependence or Abuse among Adults, by Age at First Use of Alcohol: 2000

Note: Dependence is based on the definition found in the 4^th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (APA, 1994).

Source: SAMHSA, Office of Applied Studies, National Household Survey on Drug Abuse, 2000.

2.1.2 Dependence

• In 2000, an estimated 7.1 million Americans (3.2 percent of the total population) were dependent on illicit drugs or alcohol. Of these, 0.8 million Americans were dependent on both alcohol and illicit drugs (0.4 percent of the population). An estimated 2.0 million Americans were dependent on illicit drugs but not alcohol (0.9 percent of the population). An estimated 4.3 million Americans were dependent on alcohol but not illicit drugs (1.9 percent of the total population) (Figure 1).

2.2 Age

• Rates for illicit drug dependence or abuse showed substantial variation by age (Figure 4). The rate for illicit drug dependence or abuse was 0.8 percent at age 12, and rates increased for each successive year of age until the highest rate (8.1 percent) was reached at ages 18 and 19 (data not shown in figure). After age 19, the rates declined in each successively older age group. The rate for persons aged 26 or older was 1.0 percent. The rate for persons aged 18 to 25 was 5.5 percent; the rate for persons aged 12 to 17 was 4.4 percent.

• Rates for alcohol dependence or abuse by age showed a similar pattern to rates for illicit drug dependence or abuse by age, reaching a peak at age 19 with a rate of 15.2 percent and declining for each successively older age group. The rate for persons aged 12 to 17 was 5.1 percent. The rate for persons aged 18 to 25 was 12.8 percent; the rate for persons aged 26 or older was 4.2 percent (Figure 5).

• With the exception of inhalants and the nonmedical use of psychotherapeutics, the rates of dependence on or abuse of specific illicit drugs were generally higher for persons aged 18 to 25 than for persons aged 12 to 17. The rate for inhalant dependence or abuse was 0.4 percent among persons aged 12 to 17 and 0.1 percent among persons aged 18 to 25. The rate of nonmedical dependence on or abuse of prescription psychotherapeutics was 1.1 percent among youths aged 12 to 17 and 1.0 percent among young adults aged 18 to 25.

Figure 4 Past Year Illicit Drug Dependence or Abuse, by Age: 2000

Note: Dependence is based on the definition found in the 4^th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (APA, 1994). "Illicit drug" refers to marijuana/hashish, cocaine (including crack), inhalants, hallucinogens (including LSD and PCP), heroin, or any prescription-type psychotherapeutic used nonmedically.

Source: SAMHSA, Office of Applied Studies, National Household Survey on Drug Abuse, 2000.

Figure 5 Past Year Alcohol Dependence or Abuse, by Age: 2000

Note: Dependence is based on the definition found in the 4^th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (APA, 1994).

Source: SAMHSA, Office of Applied Studies, National Household Survey on Drug Abuse, 2000.

2.3 Gender

• In 2000, males were more likely than females to be classified with dependence on or abuse of illicit drugs. Among males, 2.4 percent were classified with illicit drug dependence or abuse, while only 1.5 percent of females were classified with illicit drug dependence or abuse.

• Among youths aged 12 to 17, the rate of illicit drug dependence or abuse for males was also higher than the rate for females (4.8 vs. 4.1 percent, respectively).

• Males were more than twice as likely as females to be classified with dependence on or abuse of alcohol (7.7 vs. 3.3 percent, respectively) (Figure 6).

• However, among youths aged 12 to 17, the rates for alcohol dependence or abuse were similar for males (5.2 percent) versus females (5.1 percent).

• For blacks aged 12 to 17, the percentage classified with dependence on or abuse of illicit drugs was significantly higher for males than for females (4.5 vs. 2.4 percent, respectively), while for whites and Hispanics the rate for males was not significantly different from the rate for females (4.8 vs. 4.4 percent, and 5.2 vs. 5.0 percent, respectively).

Figure 6 Past Year Alcohol Dependence or Abuse, by Age and Gender: 2000

Note: Dependence is based on the definition found in the 4^th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (APA, 1994).

Source: SAMHSA, Office of Applied Studies, National Household Survey on Drug Abuse, 2000.

2.4 Race/Ethnicity

• For all persons aged 12 or older, blacks had a higher rate for illicit drug dependence or abuse than whites (2.3 percent for blacks and 1.8 percent for whites). However, for youths aged 12 to 17, the percentage of whites with dependence or abuse (4.6 percent) was significantly higher than the percentage of blacks with dependence on or abuse of illicit drugs (3.5 percent).

• Among persons aged 12 or older, the rate for illicit drug dependence or abuse was highest among persons reporting more than one race (5.4 percent). The next highest rate was among American Indians/Alaska Natives (4.1 percent). Asians had the lowest rate for illicit drug dependence or abuse (0.7 percent).

• In 2000 among persons aged 12 or older, the percentage of whites classified with dependence on or abuse of alcohol (5.5 percent) was not significantly different from the percentage among blacks (4.7 percent) (Figure 7). Among youths aged 12 to 17, whites were more likely than blacks to be classified with dependence on or abuse of alcohol. In this age group, the percentage of whites with dependence on or abuse of alcohol was 5.8 percent, and the percentage of blacks with dependence on or abuse of alcohol was 2.7 percent.

• Compared with other racial/ethnic categories, American Indians/Alaska Natives aged 12 or older had the highest rate of alcohol dependence or abuse (7.9 percent). The next highest rate was observed for persons reporting more than one race (6.4 percent). Hispanics had the closest rate (5.9 percent) to the rate for more than one race. The rate of alcohol dependence or abuse among Asians was 3.3 percent. Native Hawaiians/other Pacific Islanders had the lowest rate of alcohol dependence or abuse (2.8 percent).

Figure 7 Past Year Alcohol Dependence or Abuse among Persons Aged 12 or Older, by Race/Ethnicity: 2000

Note: Dependence is based on the definition found in the 4^th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (APA, 1994).

Source: SAMHSA, Office of Applied Studies, National Household Survey on Drug Abuse, 2000.

2.5 Education

• As was the case for illicit drug use, illicit drug dependence or abuse was highly correlated with educational status. Among adults aged 18 or older, those who had not completed high school had the highest rate of illicit drug dependence (2.5 percent), while college graduates had the lowest rate of illicit drug dependence (1.1 percent).

• Alcohol dependence or abuse was also correlated with educational status. The rate of alcohol dependence or abuse ranged from 6.5 percent among adults aged 18 or older who had not completed high school to 4.3 percent among college graduates.

2.6 Employment

• Rates of illicit drug dependence or abuse were correlated with current employment status. An estimated 6.7 percent of unemployed adults 18 or older were classified with dependence on or abuse of illicit drugs, while only 1.5 percent of full-time employed adults were classified as such.

• Rates of alcohol dependence or abuse were also associated with employment status. An estimated 10.7 percent of unemployed adults aged 18 or older were classified with dependence on or abuse of alcohol, while only 6.2 percent of full-time employed adults were classified with dependence on or abuse of alcohol.

2.7 Geographic Area

• Rates for illicit drug dependence or abuse among persons aged 12 or older varied by geographic division in 2000. The lowest rate of illicit drug dependence or abuse was observed in the South Atlantic, East South Central, and West North Central divisions (1.5 percent), and the highest rate was in the New England division (2.9 percent).

• Rates for alcohol dependence or abuse also varied by geographic division, ranging from 4.6 percent in the South Atlantic division to 7.3 percent in the New England division.

• In 2000, the rate for illicit drug dependence or abuse was lowest in completely rural counties (1.1 percent) and highest in large metropolitan counties (2.1 percent) (Figure 8).

• Among youths aged 12 to 17, the rate for illicit drug dependence or abuse was highest in rural counties (5.5 percent) and lowest in less urbanized nonmetropolitan counties (3.8 percent).

• The rates for alcohol dependence or abuse among persons aged 12 or older varied by county type, ranging from 4.8 percent in less urbanized nonmetropolitan areas to 5.7 percent in large metropolitan counties.

• Among youths aged 12 to 17, the rate for alcohol dependence or abuse was highest in rural counties (8.0 percent) and lowest in large metropolitan counties (4.5 percent).

Figure 8 Past Year Illicit Drug Dependence or Abuse, by County Type: 2000

Note: Dependence is based on the definition found in the 4^th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (APA, 1994). "Illicit drug" refers to marijuana/hashish, cocaine (including crack), inhalants, hallucinogens (including LSD and PCP), heroin, or any prescription-type psychotherapeutic used nonmedically.

Source: SAMHSA, Office of Applied Studies, National Household Survey on Drug Abuse, 2000.

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.    Site Map | Contact Us | Accessibility | Privacy Policy | Freedom of Information Act  Disclaimer | Department of Health and Human Services | SAMHSA | White House | USA.gov * PDF formatted files require that Adobe Acrobat Reader® program is installed on your computer. Click here to download this FREE software now from Adobe. What's New Highlights Topics Data Drugs Pubs Short Reports Treatment Help Mail OAS