Prescription Drug Dependence, Abuse, and TreatmentThis chapter presents information on dependence on and abuse of prescription-type psychotherapeutic drugs that were used nonmedically. Estimates are based on data from the 2002, 2003, and 2004 National Surveys on Drug Use and Health (NSDUHs). The chapter also provides estimates of the prevalence and patterns of the receipt of treatment for problems related to substance use and discusses the need for and receipt of treatment at specialty facilities for problems associated with substance use.
6.1. Background
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. These questions are used to classify persons as dependent on or abusing specific substances based on 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 continued use despite health or emotional problems associated with substance use, unsuccessful attempts to cut down on use, tolerance (e.g., requiring larger amounts of a substance to get desired effects), withdrawal symptoms, reducing other activities in order to use substances, spending a lot of time engaging in activities related to substance use, or using the substance in greater quantities or for a longer time than intended. 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 is considered to be a more severe substance use problem than abuse. Although individuals may meet the criteria specified for both dependence and abuse, persons are classified with abuse of a particular substance only if they are not classified as dependent on that substance. In this chapter, persons meeting the criteria for either dependence or abuse are counted together. It should be noted that the NSDUH questionnaire does not include specific dependence and abuse questions for methamphetamine because the DSM-IV criteria pertain to stimulants as a whole.
6.2. Trends in Dependence or Abuse
The estimated numbers and rates of past year prescription drug dependence or abuse for any psychotherapeutic drug and the specific drug classes did not change significantly from 2002 to 2004 among persons aged 12 or older (Figure 6.1 and Table 6.1). In 2004, approximately 2.0 million persons aged 12 or older met the criteria for dependence or abuse involving any prescription psychotherapeutic drug that was used nonmedically, including 1.4 million for pain relievers, 573,000 for tranquilizers, 470,000 for stimulants, and 128,000 for sedatives.
Figure 6.1 Substance Dependence or Abuse for Nonmedical Use of Prescription Psychotherapeutic Drugs in the Past Year for Persons Aged 12 or Older, by Drug Type: Numbers (in Thousands), 2002-2004
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a Difference between this estimate and the 2004 estimate is statistically significant at the .05 level.
b Difference between this estimate and the 2004 estimate is statistically significant at the .01 level.
Source: SAMHSA, Office of Applied Studies, National Survey on Drug Use and Health, 2002, 2003, and 2004.
Within separate age groups, few year-to-year changes in the rates of dependence or abuse reached statistical significance. Among youths aged 12 to 17, the rate of pain reliever dependence or abuse increased from 1.0 percent in 2002 to 1.2 percent in 2004 (Figure 6.2). Among young adults aged 18 to 25, dependence or abuse involving this class of drugs increased from 1.1 percent in 2003 to 1.4 percent in 2004, but this change simply restored the rate observed in 2002 (1.4 percent). The apparent decline in the rate of pain reliever dependence or abuse among adults aged 26 or older was not statistically significant. There were no statistically significant changes in the rates of abuse or dependence for specific age groups for other classes of psychotherapeutic drugs that were used nonmedically.
Figure 6.2 Substance Dependence or Abuse for Nonmedical Use of Prescription Pain Relievers in the Past Year, by Age Group: Percentages, 2002-2004
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a Difference between this estimate and the 2004 estimate is statistically significant at the .05 level.
b Difference between this estimate and the 2004 estimate is statistically significant at the .01 level.
Source: SAMHSA, Office of Applied Studies, National Survey on Drug Use and Health, 2002, 2003, and 2004.
6.3. Demographic Differences in Dependence or Abuse
Data aggregated for 2002, 2003, and 2004 provide sufficient numbers of respondents to permit reliable examination of differences in past year dependence or abuse for any prescription psychotherapeutic drug and the four therapeutic classes of psychotherapeutic drugs according to age, gender, race/ethnicity, and other covariates (Table 6.2). Consistent with the single-year trend data, combined data from the 2002 through 2004 surveys yielded an annual average of 2.0 million persons aged 12 or older who met the criteria for prescription psychotherapeutic drug dependence or abuse in the past year. Annual average numbers of people aged 12 or older who met dependence or abuse criteria for specific classes of psychotherapeutic drugs were 1.4 million for pain relievers, 505,000 for tranquilizers, 424,000 for stimulants, and 147,000 for sedatives.
As shown in Figure 6.3, young adults aged 18 to 25 had the highest rates of past year dependence or abuse involving pain relievers, tranquilizers, and stimulants, the three most frequently reported classes of nonmedically used prescription psychotherapeutic drugs. Youths aged 12 to 17 had the second highest rates of dependence or abuse involving these drugs. Rates of dependence or abuse among adults aged 50 or older were lowest for each of these drug classes.
Overall, rates of past year dependence and abuse were comparable for males and females for any misused prescription psychotherapeutic drug and each of the therapeutic drug classes (Table 6.2). When gender differences are considered for different age groups, however, a different pattern emerges. Among youths aged 12 to 17, the rate of dependence or abuse was higher among females than males for any prescription psychotherapeutic drug (1.8 vs. 1.1 percent, respectively), pain relievers (1.4 vs. 0.8 percent), tranquilizers (0.4 vs. 0.3 percent), and stimulants (0.5 vs. 0.3 percent) (Figure 6.4). For young adults aged 18 to 25, however, males were more likely than females to meet the criteria for past year pain reliever dependence or abuse (1.4 vs. 1.1 percent).
Figure 6.3 Substance Dependence or Abuse for Nonmedical Use of Pain Relievers, Tranquilizers, and Stimulants in the Past Year, by Age Group: Annual Averages Based on 2002-2004
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Source: SAMHSA, Office of Applied Studies, National Survey on Drug Use and Health, 2002, 2003, and 2004.
Figure 6.4 Substance Dependence or Abuse for Nonmedical Use of Pain Relievers in the Past Year, by Age Group and Gender: Annual Averages Based on 2002-2004
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Source: SAMHSA, Office of Applied Studies, National Survey on Drug Use and Health, 2002, 2003, and 2004.
Considered by race/ethnicity, the rate of past year dependence or abuse involving any nonmedically used prescription psychotherapeutic drug was higher for American Indians or Alaska Natives (2.0 percent) and whites (0.9 percent) than for blacks (0.5 percent) or Asians (0.5 percent) (Figure 6.5 and Table 6.2). However, whites and Hispanics had similar rates (0.8 percent for Hispanics). Rates also were not significantly different between whites and American Indians or Alaska Natives. Although the rate of dependence or abuse appeared to be high for Native Hawaiians or Other Pacific Islanders, it was not significantly different from other rates shown in Figure 6.5.
A similar pattern of differences held for pain relievers (0.6 percent for whites and Hispanics, 0.4 percent for blacks, and 0.3 percent for Asians). For pain relievers, the rate of dependence or abuse also was higher among American Indians or Alaska Natives (1.2 percent) than blacks or Asians. Past year dependence or abuse involving tranquilizers was higher among American Indian or Alaska Natives (0.9 percent) than among whites (0.2 percent) or blacks (0.1 percent); the rates for whites and Hispanics (0.2 percent) also were higher than that for blacks.
Figure 6.5 Substance Dependence or Abuse for Nonmedical Use of Any Prescription Psychotherapeutic Drug in the Past Year, by Race/Ethnicity: Annual Averages Based on 2002-2004
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Source: SAMHSA, Office of Applied Studies, National Survey on Drug Use and Health, 2002, 2003, and 2004.
6.4. Geographic Differences in Dependence or Abuse
Small but statistically significant regional differences were observed in rates of past year dependence or abuse involving some prescription-type psychotherapeutic drugs that were used nonmedically (Table 6.3).1 The rate for past year dependence or abuse involving any prescription psychotherapeutic drug was higher in the West (1.0 percent) and South (0.9 percent) than in the Northeast (0.7 percent) and Midwest (0.7 percent). Regional differences also were found in the rates of dependence on or abuse of pain relievers and tranquilizers. For pain relievers, the rate of past year dependence or abuse was higher in the South (0.7 percent) and West (0.6 percent) than in the Midwest (0.5 percent). For tranquilizers, dependence or abuse was more prevalent in the South (0.3 percent) than in the West (0.2 percent) or Midwest (0.2 percent).
Differences in the rate of past year dependence or abuse were found by census division for any prescription psychotherapeutic drug, pain relievers, tranquilizers, and stimulants (Table 6.3). For any psychotherapeutic drug, the rate of dependence or abuse was lower in the Middle Atlantic (0.6 percent) and West North Central (0.6 percent) Divisions than in the East South Central (1.2 percent), Pacific (1.0 percent), West South Central (1.0 percent), Mountain (0.9 percent), and South Atlantic (0.8 percent) Divisions (Figure 6.6). The rate in the East North Central Division (0.7 percent) was lower than that in the East South Central, West South Central, Mountain, and Pacific Divisions. Although the New England Division appeared to have a high prevalence of dependence or abuse for any psychotherapeutic drug (1.1 percent), only the West North Central Division had a significantly lower rate than that for New England.
Figure 6.6 Substance Dependence or Abuse for Nonmedical Use of Any Prescription Psychotherapeutic Drug in the Past Year, by Census Division: Annual Averages Based on 2002-2004
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Source: SAMHSA, Office of Applied Studies, National Survey on Drug Use and Health, 2002, 2003, and 2004.
The rank ordering of the census divisions by the rate of past year pain reliever dependence or abuse generally was similar to that for any prescription psychotherapeutic drug. One exception for pain relievers was that the West North Central Division had the lowest rate (0.3 percent), followed by the Middle Atlantic Division (0.4 percent). The rates in those census divisions were lower than those in the East South Central (1.0 percent), New England (0.9 percent), West South Central (0.7 percent), Pacific (0.7 percent), and Mountain (0.6 percent) Divisions.
Past year dependence and abuse varied by county type for any prescription psychotherapeutic drug, pain relievers, and stimulants. For any psychotherapeutic drug, the highest rate of past year dependence or abuse occurred in counties in small metropolitan areas with fewer than 250,000 population (1.2 percent); the lowest rate was found in completely rural counties (0.6 percent). This same pattern held for pain relievers (0.9 and 0.4 percent, respectively). For stimulants, the rate of dependence or abuse was somewhat lower in large metropolitan areas (0.1 percent) than in small metropolitan areas with fewer than 1 million population (0.2 percent) and less urbanized nonmetropolitan counties (0.3 percent).
Further information on geographic differences can be found in Chapter 7, which presents estimates by State.
6.5. Dependence or Abuse among Past Year Users
To some extent, variations in the rates of past year dependence or abuse are driven by differences in the rates of past year use. In this section, the rate of dependence or abuse involving prescription drugs is examined among users of the respective drugs to address questions of the relative propensity of persons in a particular demographic group or users of a particular drug to exhibit dependence or abuse once they have used the drug. The statistics discussed here sometimes are referred to as "conditional rates" because they refer to the rate of dependence or abuse, given use in the same time period.
Overall, aggregate data for 2002, 2003, and 2004 indicate that 13.5 percent of past year nonmedical users of any prescription-type psychotherapeutic drug met the criteria for dependence on or abuse of any such drug (Table 6.4). For the four therapeutic drug classes, the conditional rates of dependence or abuse were 12.7 percent for pain relievers, 10.1 percent for tranquilizers, 14.4 percent for stimulants, and 17.3 percent for sedatives.
Nonmedical users aged 12 to 17 had higher rates of dependence or abuse than those aged 18 to 25 regardless of the drug class (Figure 6.7). For any psychotherapeutic drug, 15.9 percent of youths aged 12 to 17 and 12.7 percent of young adults aged 18 to 25 who were past year users met the criteria for dependence or abuse. For pain relievers, adults aged 26 or older had higher conditional rates of dependence or abuse than young adults (13.3 vs. 10.9 percent). For tranquilizers, the rate for youths (15.3 percent) was higher than that for either young adults (9.2 percent) or adults aged 26 or older (9.7 percent).
Male and female past year nonmedical users of prescription drugs did not differ significantly in the rate of past year dependence on or abuse of those drugs, either overall or for the respective therapeutic drug classes. For example, the conditional rates of pain reliever dependence or abuse were 12.4 percent for males and a comparable 13.2 percent for females.
Figure 6.7 Substance Dependence or Abuse for Nonmedical Use of Prescription Psychotherapeutic Drugs in the Past Year among Past Year Nonmedical Users of Those Drugs, by Drug Type and Age Group: Annual Averages Based on 2002-2004
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Source: SAMHSA, Office of Applied Studies, National Survey on Drug Use and Health, 2002, 2003, and 2004.
6.6. Dependence or Abuse as a Function of Age at First Use
Table 6.5 presents information on the rates of past year dependence on or abuse of prescription drugs among lifetime nonmedical users aged 18 or older according to the age at which they first used those drugs. Except for sedatives, the risk of dependence or abuse was higher among persons who initiated nonmedical use before age 16 compared with those who were age 16 or older when they first used the respective drugs (Figure 6.8). This same pattern held for lifetime nonmedical users aged 18 to 25 and for those aged 26 or older. For example, 6.6 percent of persons aged 26 or older who were lifetime misusers of pain relievers and who initiated use before age 16 met the criteria for pain reliever dependence or abuse. Among lifetime pain reliever misusers in this age group who initiated use after age 16, only 3.3 percent met the criteria for dependence or abuse. Although this general pattern also was observed for sedatives, the rates of dependence or abuse were not significantly different between persons who initiated nonmedical sedative use before age 16 and those who initiated use at age 16 or older.
Figure 6.8 Past Year Substance Dependence or Abuse for Nonmedical Use of Prescription Psychotherapeutic Drugs among Lifetime Users Aged 18 or Older, by Drug Type and Age at First Use: Annual Averages Based on 2002-2004
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Source: SAMHSA, Office of Applied Studies, National Survey on Drug Use and Health, 2002, 2003, and 2004.
6.7. Treatment for Any Illicit Drug Use
This section presents findings on treatment received in the past year to stop or reduce the use of any illicit drug or for medical problems associated with misusing these drugs among persons who met the criteria for dependence on or abuse of prescription drugs in the past year. This measure includes treatment received in the past year at any location, such as a hospital (inpatient), rehabilitation facility (outpatient or inpatient), mental health center, emergency room, private doctor's office, prison or jail, or a self-help group, such as Alcoholics Anonymous or Narcotics Anonymous. Treatment at a specialty facility in the past year includes only treatment at a hospital (inpatient), a rehabilitation facility (inpatient or outpatient), or a mental health center. Findings for these analyses are shown in Table s 6.6 and 6.7.
In 2002, 2003, and 2004, an annual average of 290,000 persons received treatment for illicit drug use in the past year and met the criteria for dependence on or abuse of prescription psychotherapeutic drugs in the past year. This number includes treatment at any type of facility, both specialty and nonspecialty. Among the therapeutic classes of prescription drugs, those treated included an annual average of 210,000 persons who were dependent on or abusing pain relievers, 106,000 who were dependent on or abusing tranquilizers, 104,000 who were dependent on or abusing stimulants, and 39,000 who were dependent on or abusing sedatives (Table 6.6).2 The percentages receiving treatment for illicit drug use in the past year constituted 14.5 percent of those dependent on or abusing any prescription drug, 14.6 percent for pain relievers, 21.1 percent for tranquilizers, and 24.2 percent for stimulants. Too few persons met the criteria for dependence on or abuse of sedatives to produce estimates with adequate precision (see Appendix B for a discussion of precision requirements).
Rates of past year specialty treatment for any illicit drug among those dependent on or abusing prescription psychotherapeutic drugs in the past year were 12.5 percent for any psychotherapeutic drug, 12.9 percent for pain relievers, 19.3 percent for tranquilizers, and 20.4 percent for stimulants (Table 6.7). Viewing these findings from a different perspective, an estimated 87.5 percent of those meeting the criteria for dependence on or abuse of a prescription psychotherapeutic drug in the past year did not receive specialty treatment for any illicit drug use in that period, and 85.5 percent did not receive any treatment in the past year, either at a specialty or nonspecialty facility.
Receipt of past year specialty treatment among persons dependent on or abusing prescription psychotherapeutic drugs in the past year varied by drug category and age. The rate of treatment for an illicit drug problem was lower for persons aged 12 to 17 who were dependent on or abusing any psychotherapeutic drug (7.9 percent) than for their counterparts who were aged 18 to 25 (12.7 percent) or aged 26 or older (13.9 percent).
6.8. Treatment for Problems Related to Nonmedical Prescription Drug Use
For a subset of persons who received treatment for illicit drugs in the past year, it is possible to identify those whose treatment was specifically for problems resulting from nonmedical use of prescription psychotherapeutic drugs. These data are presented in Table 6.8 and pertain to persons whose last or current treatment in the past year was for one or more prescription psychotherapeutic drugs. Treatment at any type of facility—not necessarily specialty facilities—is included. An annual average of 209,000 persons treated in the past year met the criteria for dependence on or abuse of any prescription psychotherapeutic drug and received their last or current treatment for problems with any psychotherapeutic drug. Similarly, 135,000 persons met the dependence or abuse criteria and received their last or current treatment for pain relievers, 50,000 did so for tranquilizers, 64,000 did so for stimulants, and 34,000 did so for sedatives. Further estimates are not available for those treated for problems with sedatives due to small numbers.
Among those dependent on or abusing any prescription-type psychotherapeutic in the past year, 10.5 percent received treatment in the past year specifically for one or more psychotherapeutic drugs. Comparable rates for other psychotherapeutic drug categories were 9.4 percent for pain relievers, 9.8 percent for tranquilizers, and 15.0 percent for stimulants. As was the case for treatment for any illicit drug in the past year, the percentage of persons who were dependent on or abusing any psychotherapeutic drug and who last received treatment for one or more of these drugs was lower for persons aged 12 to 17 than for those aged 18 to 25 (6.5 vs. 11.6 percent). Persons aged 12 to 17 who were dependent on or abusing stimulants also were less likely than their counterparts aged 18 to 25 to have received treatment for their problems with stimulants during their last or current treatment episode (10.0 vs. 19.0 percent). There were no significant differences by gender.
6.9. Summary
This chapter presented findings for substance dependence, abuse, and treatment in the past year related to the nonmedical use of prescription psychotherapeutic drugs. The chapter also presented data on selected correlates of dependence or abuse, based on combined data from the 2002 through 2004 surveys. In addition, findings were presented for treatment for nonmedical psychotherapeutic drug use based on the combined data.
Trend data indicated that rates of dependence or abuse for nonmedical use of psychotherapeutic drugs among persons aged 12 or older did not change significantly from 2002 to 2004. In 2004, approximately 2.0 million persons aged 12 or older met the criteria for dependence or abuse involving any prescription psychotherapeutic drug that was used nonmedically, including 1.4 million for pain relievers, 573,000 for tranquilizers, 470,000 for stimulants, and 128,000 for sedatives.
The prevalence of dependence or abuse was higher among young adults aged 18 to 25 for pain relievers, tranquilizers, and stimulant compared with the rates in other age groups; these findings were based on combined data from the 2002 through 2004 surveys. Males and females aged 12 or older had comparable rates of dependence or abuse, but gender differences occurred within specific age groups. Among youths aged 12 to 17, females had higher rates of dependence or abuse involving any psychotherapeutic drug, pain relievers, tranquilizers, and stimulants than did males. For young adults aged 18 to 25, however, males were more likely than females to meet the criteria for dependence or abuse involving pain relievers. The rate of dependence or abuse for any prescription psychotherapeutic drug was higher for American Indians or Alaska Natives and whites than for blacks or Asians. Regional differences in rates of dependence or abuse for psychotherapeutic drugs were small, although some differences were significant.
Among persons who used psychotherapeutic drugs nonmedically in the past year, 13.5 percent met the criteria for dependence on or abuse of at least one prescription psychotherapeutic drug. The prevalence of dependence or abuse among past year misusers of any psychotherapeutic drug was higher for youths aged 12 to 17 than for young adults aged 18 to 25.
For any psychotherapeutic drug, pain relievers, tranquilizers, and stimulants, the risk of dependence or abuse for psychotherapeutic drugs was greater for persons aged 18 or older who initiated nonmedical use before age 16 compared with those who initiated use at age 16 or older. For sedatives there was no significant difference in rates of dependence or abuse by age at first use.
An estimated 290,000 persons who met the criteria for past year dependence or abuse for psychotherapeutic drugs received treatment in the past year for use of any illicit drug, and 209,000 received their last or most current past year treatment specifically for a psychotherapeutic drug they were dependent on or abusing. Thus, the large majority of persons aged 12 or older who were dependent on or abusing prescription psychotherapeutic drugs in the past year did not receive illicit drug use treatment in the past year.
