5. Substance Dependence, Abuse, and Treatment Need

The National Survey on Drug Use and Health (NSDUH) includes a series of questions to assess the prevalence of substance use disorders (i.e., dependence on or abuse of a substance) in the past 12 months. Substances include alcohol and illicit drugs, such as marijuana, cocaine, heroin, hallucinogens, and inhalants, and nonmedical use of prescription-type drugs. These questions are used to classify persons as being dependent on or abusing specific substances based on criteria specified in the Diagnostic and Statistical Manual of Mental Disorders, 4^th edition (DSM-IV) (American Psychiatric Association [APA], 1994). The questions on dependence ask about health and 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 substance use. 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.

An estimated 22.4 million persons aged 12 or older in 2004-2005 were classified with dependence on or abuse of any illicit drug or alcohol in the past year. Of these, 7.1 million were dependent on or had abused illicit drugs, and 18.7 million were dependent on or had abused alcohol (see Tables 16, 18, and 20, http://www.oas.samhsa.gov/2k5State/ageTabs.htm).

5.1 Alcohol Dependence or Abuse

Nationally in 2004-2005, 7.7 percent of the population aged 12 or older was classified with dependence on or abuse of alcohol in the past year (Table B.16). Persons aged 18 to 25 had the highest rate of alcohol dependence or abuse (17.5 percent) in the Nation. Wisconsin had the highest rate (10.1 percent) among persons aged 12 or older. Georgia had the lowest rate (6.0 percent). Three States (Montana, North Dakota, and Wisconsin) ranked in the highest fifth for all three age groups (12 to 17, 18 to 25, and 26 or older) and among all persons 12 or older (Figures 5.1 to 5.4).

Past year dependence on or abuse of alcohol remained unchanged between 2003-2004 and 2004-2005 at 7.6 to 7.7 percent for all persons aged 12 or older (Table C.16). The rates for each of the age groups also remained relatively constant during these years. Across all age groups, including the combined 12 or older group, there were seven significant changes among the States, and five of them were increases.

In 2004-2005, 3.4 percent of persons aged 12 or older were estimated to be dependent on alcohol in the past year, representing about 44 percent of those who were dependent on or had abused alcohol in the past year (Table s B.16 and B.17). State estimates for alcohol dependence for persons aged 12 or older ranged from 2.8 percent in Delaware, Georgia, and New Jersey to 5.3 percent in the District of Columbia. The highest rates for alcohol dependence occurred in the 18 to 25 age group. In 2004-2005, about 7 percent of young adults were dependent on alcohol in the past year. Seven States that ranked in the highest fifth in the 12 or older population for dependence on or abuse of alcohol in the past year also were ranked in the highest fifth for past year alcohol dependence (Figures 5.1 and 5.5). None of the States showed any increase or decrease in past year alcohol dependence rates between 2003-2004 and 2004-2005 either among the 12 or older population or in any of the age subgroups (Table C.17).

5.2 Illicit Drug Dependence or Abuse

Nationally in 2004-2005, about 2.9 percent of persons aged 12 or older were dependent on or had abused illicit drugs in the past year (Table B.18). The District of Columbia had the highest rate of past year illicit drug dependence or abuse (3.8 percent) among persons aged 12 or older, and Iowa had the lowest rate (2.3 percent). The highest rates for past year illicit drug dependence or abuse occurred in the 18 to 25 age group, with Connecticut having the highest rate (12.9 percent). The only regional change in the rates of past year illicit drug dependence or abuse occurred in the Midwest where there was a decrease among youths aged 12 to 17 from 5.4 percent in 2003-2004 to 4.8 percent in 2004-2005 (Table C.18). Both Hawaii and Michigan showed decreases among youths for the time period, while Connecticut, Michigan, and Tennessee all displayed increases among young adults aged 18 to 25. New Mexico showed a decline among the age 12 or older population.

The percentage of persons in 2004-2005 estimated to be dependent on illicit drugs in the past year was 2.0 percent (about two thirds of those who were estimated to be dependent on or had abused illicit drugs in the past year) (Table s B.18 and B.19). As in the case of persons 12 or older being dependent on or having abused illicit drugs in the past year, the District of Columbia had the highest percentage of persons who were dependent on illicit drugs in the past year (2.8 percent). Nationally, there was a significant increase in the percentage of persons dependent on illicit drugs among the 18 to 25 age group from 5.4 percent in 2003-2004 to 5.7 percent in 2004-2005. Some of the same States and age groups that had changes for past year illicit drug dependence or abuse had similar changes for past year illicit drug dependence between 2003-2004 and 2004-2005. The Michigan rate among youths aged 12 to 17 decreased from 3.3 to 2.6 percent; and both Connecticut and Michigan had increases among young adults aged 18 to 25, from 6.3 to 8.8 percent and from 5.7 to 7.1 percent, respectively (Table C.19).

There was a slight relationship in 2004-2005 between the high rates of past year illicit drug dependence and the high rates of past year cocaine use for persons aged 12 or older at the State level. Seven States (Alaska, Colorado, Connecticut, District of Columbia, Massachusetts, Rhode Island, and Vermont) ranked in the highest fifth for both measures among persons aged 12 or older (Figures 2.24 and 5.13). The relationship between low rates of past year illicit drug dependence and low rates of past year cocaine use for persons aged 12 or older at the State level was similar. Five States ranked in the lowest quintile for both measures in 2004-2005.

5.3 Alcohol or Illicit Drug Dependence or Abuse

The national rate in 2004-2005 for past year dependence on or abuse of alcohol or illicit drugs among persons aged 12 or older was 9.3 percent (Table B.20). When examining dependence on or abuse of alcohol or illicit drugs at the State level, the States with high rates for alcohol dependence or abuse tended to rank in the top fifth for alcohol and illicit drug dependence or abuse combined because alcohol accounts for most of the substance dependence or abuse. Nine States that ranked in the highest fifth for past year alcohol dependence or abuse also ranked in the top fifth for past year dependence on or abuse of alcohol or illicit drugs among persons aged 12 or older (Arizona, Colorado, District of Columbia, Montana, Nebraska, North Dakota, South Dakota, Wisconsin, and Wyoming) (Figures 5.1 and 5.17).

State percentages for past year dependence on or abuse of alcohol or illicit drugs among persons aged 12 or older ranged from a low of 7.7 percent in Georgia to a high of 11.6 percent in the District of Columbia (Table B.20). Only three States, Colorado, Montana, and Wisconsin, were in the highest fifth for all three age groups (12 to 17, 18 to 25, and 26 or older) and among all persons 12 or older (Figures 5.17 to 5.20).

Among all persons aged 12 or older, the rate of past year dependence on or abuse of alcohol or illicit drugs remained nearly constant at 9.2 to 9.3 percent, respectively, in 2003-2004 and 2004-2005 (Table C.20). The only significant national change occurred among youths aged 12 to 17, where there was a decrease from 8.9 to 8.4 percent. Eleven statistically significant changes were spread among eight States across the different age groups. Six of those were increases, and five were decreases. There were no changes in the rate of past year dependence on or abuse of alcohol or illicit drugs observed among persons aged 26 or older.

5.4 Needing But Not Receiving Treatment for Illicit Drug Problems

The definition of a person needing but not receiving treatment for an illicit drug problem is that the person meets the criteria for abuse of or dependence on illicit drugs according to the DSM-IV, but has not received specialty treatment for an illicit drug problem in the past year. Specialty treatment is treatment received at a drug and alcohol rehabilitation facility (inpatient or outpatient), hospital (inpatient only), or mental health center. The national rate in 2004-2005 for needing but not receiving treatment for an illicit drug problem among persons aged 12 or older was 2.7 percent, unchanged from 2003-2004 (Table s B.21 and C.21).

In 2004-2005, Alaska had the highest percentage of persons aged 12 or older needing but not receiving treatment for an illicit drug use problem (3.5 percent), while North Dakota had the lowest rate (2.0 percent) (Table B.21). The States in the top fifth for needing but not receiving treatment for an illicit drug use problem among persons 12 or older were distributed across the West (four States), Northeast (three States), and the South (two States and the District of Columbia) (Figure 5.21).

The only change at the regional level in the percentage needing but not receiving treatment for illicit drug use was a decline in the 12 to 17 age group in the Midwest, from 5.1 percent in 2003-2004 to 4.5 percent in 2004-2005 (Table C.21). That decline was accompanied by a decrease among youths in Hawaii from 5.6 to 4.2 percent and a decrease among Michigan youths from 5.8 to 4.5 percent. Three States had increases in the 18 to 25 age group. Connecticut's rate increased from 9.3 to 12.3 percent; Michigan's rate increased from 7.3 to 8.8 percent; and Tennessee showed an increase from 6.7 to 9.1 percent among persons aged 18 to 25. There were no significant changes in the 26 or older population.

5.5 Needing But Not Receiving Treatment for Alcohol Problems

The definition of a person needing but not receiving treatment for an alcohol problem is that the person meets the criteria for abuse of or dependence on alcohol according to the DSM-IV, but has not received specialty treatment for an alcohol problem in the past year. The percentage of persons aged 12 or older needing but not receiving treatment for alcohol problems (7.4 percent) in 2004-2005 was almost 3 times larger than the corresponding percentage for persons needing but not receiving treatment for illicit drug problems (2.7 percent) (Table s B.21 and B.22).

States in the top fifth for needing but not receiving treatment for alcohol problems among persons aged 12 or older in 2004-2005 were primarily Midwestern (five States) or Western (four States) (Figure 5.25). Only Colorado and the District of Columbia were ranked in the highest quintile for both needing but not receiving treatment for an alcohol problem and needing but not receiving treatment for an illicit drug problem among persons aged 12 or older (Figures 5.21 and 5.25). Four States were ranked in the top fifth for needing but not receiving treatment for alcohol problems among persons aged 12 or older and in each of the three age categories (12 to 17, 18 to 25, and 26 or older): Nebraska, North Dakota, Wisconsin, and Wyoming (Figures 5.25 to 5.28). Wisconsin had the highest rate of needing but not receiving treatment for an alcohol problem (9.6 percent) (Table B.22). Georgia had the lowest rate (5.7 percent).

Among persons aged 12 or older, there were no significant changes between 2003-2004 and 2004-2005 for the Nation as a whole; however, there was a slight increase in the South among persons aged 26 or older from 5.4 to 5.8 percent (Table C.22). Florida was the only State in the South having an increase, from 5.7 to 6.6 percent, among persons aged 26 or older. Florida also had an increase in the rate of the persons needing but not receiving treatment for alcohol use in the overall population 12 or older, from 6.8 percent in 2003-2004 to 7.7 percent in 2004-2005. Michigan and Utah both had increases in the 18 to 25 age group. South Carolina had a decrease in the 18 to 25 age group, and Hawaii had a decrease in the 12 to 17 age group.