CHAPTER 3
TRENDS IN DRUG USE

TRENDS IN INCIDENCE

Before people begin to use a drug more or less regularly, they have to use it for the first time. The government's drug experts call first use of a drug its "incidence" of use or the event of "initiation." The government's chief drug survey, the National Survey on Drug Use and Health (formerly called the National Household Survey on Drug Abuse, conducted annually by the Substance Abuse and Mental Health Services Administration (SAMHSA) of the U.S. Department of Health and Human Services, tracks both first use of important drugs and their prevalence. Prevalence, discussed in the next section, is the extent of current and lifetime use of drugs by the population. Increases in incidence have been found to foreshadow increases in prevalence; similarly, when the number of initial uses of a drug drop, after a lag of years so will the number of people who regularly take the drug.

The survey began in 1971 and has increased from a survey of about three thousand respondents every two to three years to almost seventy thousand people in the fifty states and Washington, D.C., every year. The latest survey available, 2003 National Survey on Drug Use and Health (NSDUH), was published in September of 2004 (http://www.oas.samhsa.gov/nhsda/2k3nsduh/2k3ResultsW.pdf). The population surveyed by SAMHSA consists of noninstitutionalized civilians over the age of twelve living in households, dormitories, homeless shelters, rooming houses, and military institutions. This excludes homeless people not in shelters, active-duty military personnel, and persons in jails and prisons, but the survey is still considered to be the most comprehensive analysis of drug use in America. The results are statistically projected to the entire population to produce an estimate of drug use prevalence nationwide. Survey methods were changed in 1999 when SAMHSA switched from a paper-and-pencil survey to a computer-assisted survey. Therefore, the results for the years from 1999 forward are not strictly comparable to earlier years. The changes were introduced so that more accurate state-level results could be obtained and over-or under-sampling of regions (urban versus rural, for instance) or populations (African-Americans versus whites) could be corrected.

SAMHSA tracks initial use by asking those who participate in the National Survey when they first used a drug. Respondents also report how old they are. SAMHSA can thus calculate the number of people first using a drug in any given year—and also how old they were at that time. People who use drugs have a higher rate of mortality than nonusers; current samples cannot, of course, include the dead. Reporting on the "harder" drugs is also less reliable because of what SAMHSA calls "underreporting due to desire for social acceptability or fear of disclosure" ("Chapter 5. Trends in Initiation of Substance Use," 2003 National Survey on Drug Use and Health [NSDUH], Rockville, MD: SAMHSA, 2004).

Initial use shows different cycles for different drugs over the last four decades. The peaks and troughs of different drugs do not always coincide. The patterns suggest a demographic underpinning, since initial drug use is generally a youth phenomenon, and different drugs are used more by some age groups than others. As the number of people in each age category shifts, so do the incidents of drug usage in each category.

Marijuana

By far the most frequently tried illegal substance is marijuana. In the thirty-seven-year period shown in Figure 3.1, initial use of marijuana shows several peaks, with two of the highest in 1973 and 2000. In 1973, 3.5 million people tried marijuana for the first time. Initial tries dropped to about one and a half million by 1990. New tries then climbed to a new peak of 2.9 million first-time users in 2000, before tapering off slightly to 2.6 million in 2002, about two-thirds of whom were under age eighteen.

The demographic underpinning is suggested by the age of members of the baby boom generation at the 1973 peak of marijuana experimentation and the age of the so-called "baby boom echo" (children of the baby boom) in 2000. A large percentage of the boomers (born between 1945 and 1960) were between sixteen and twenty-five years of age in the mid-1970s; at around forty million strong, this was the largest single group of this age ever in America ("Live Births by Age of Mother and Race: United States, 1933-98," Washington, DC: National Center for Health Statistics, http://www.cdc.gov/nchs/data/natality/mage33tr.pdf).

The second peak in this series (in 2000) suggests that the children of those who experimented in the 1970s were now doing the same thing. In 2000 the youngest boomers were forty and the oldest fifty-five, and all were of an age to have teenagers in the house or away in college.

With the passage of time during this thirty-seven-year period, the younger age group also became more important. Experimentation is driven by the under-eighteen age group. (See Figure 3.1.) SAMHSA also calculates the average age of the initial users. The general trend over time has been that those trying marijuana are younger and younger on average. The average age in the late 1960s was about nineteen; the average age in 2002 was 17.2.

Cocaine

Data on the incidence of cocaine use produce a different pattern in the 1965-2002 period. (See Table 3.1.) The number of initial users reached its peak in 1980 (1.56 million), seven years after the first marijuana peak.

Cocaine is used by an older age group. The average age of cocaine initiates was around twenty-two years in the early 1980s, rose to about twenty-three in the late 1980s, then declined to about twenty-one by the late 1990s. The average age of initiates in 2002 was 20.3 years.

Until the mid-1980s cocaine was a relatively expensive powdered drug snorted by well-off users at parties. The much cheaper crack cocaine, which could be smoked, appeared early in the 1980s but did not reach mass distribution until some years later.

Hallucinogens, Inhalants, and Prescription Drugs

Demographics underlie but do not entirely explain the incidence of drug use. The availability of drugs, their cost, the emergence of new varieties, the dangers associated with the drug (and the spread of information about such dangers) all have a bearing. Hallucinogens, inhalants, and psychotropic medications used in nonmedical settings have similar usage patterns.

HALLUCINOGENS.

Drugs that produce hallucinations reached their first-use peak in 2001. (See Figure 3.2.) The best known and most commonly used of these drugs is LSD (as measured in prevalence). The two other hallucinogens tracked by SAMHSA are PCP and Ecstasy (MDMA). In 2001, according to SAMHSA's 2003 report, 1.6 million people first took a hallucinogenic drug. The earlier peak in usage came in 1972, around the same time marijuana reached its highest incidence.

INHALANTS.

Substances intended for other purposes but inhaled for an effect include glue, gasoline, paint, and turpentine. Inhalant first use increased during the 1990s, with teenagers generally fueling the trend. Though a fairly steady group of eighteen- to twenty-year-olds has continued to join the inhalers over the past four decades, the growth in incidents has been driven mainly by the younger grouping of those twelve to seventeen. More than half (52%) of those who sniffed such items in 1978 were twelve to seventeen. According to the SAMHSA's 2003 report, in 2002 about one million people tried inhalants for the first time. As in the past, this group was dominated by those under eighteen, representing 78% of new users.

PRESCRIPTION DRUGS.

SAMHSA data show that use of prescription-type pain relievers as recreational drugs rather than for medical purposes has slowly risen from 1965 to 1995, after which it dramatically rose. Similar trends are seen for other prescription drugs, such as tranquilizers, stimulants, and sedatives. Incidence of these drugs reached early peaks in the mid- to late 1970s. All but the sedatives reached new highs since 2000, with pain relievers leading the way. The average age of those using pain relievers was twenty-two in 2002, according to SAMHSA's 2003 report. About 2.5 million new people tried prescription pain relievers each year from 2000 to 2002.

Incidence of Heroin Use

People who try heroin for the first time are, on average, the oldest "drug experimenters." According to a previous SAMHSA report, in the 1965-2000 period the average age of initial heroin users was 22.8 years. In the 1980-2000 period the average was 24.8, and in the 1990-2000 period it was 25.4. The users also represent the smallest number of people who try a drug. The 2003 SAMHSA study reports that from 1995 to 2002 the annual number of new heroin users ranged from 121,000 to 164,000. Incidence reporting on heroin may be the least reliable because of social bias associated with heroin addicts and because many addicts die and thus do not participate in SAMHSA's household surveys that look back on the 1960s and 1970s.

TRENDS IN PREVALENCE

The prevalence of drug use is tracked by SAMHSA in its National Survey and by the Drug Abuse Warning Network (DAWN), also sponsored by SAMHSA, which collects data from the emergency departments of the nation's hospitals. DAWN also collects drug-related mortality data, as does the National Center for Health Statistics, another element of the U.S. Department of Health and Human Services. Data from these sources are presented here. A discussion of different groupings of drug users (pregnant women, youths, the working population, military people, and persons arrested) is presented in Chapter 4.

The findings of SAMHSA's National Survey will be explored in this section, and the other surveys will be discussed separately below. The National Survey divides illicit drug use responses into three categories: lifetime use, past year use, and current use. Current use is defined as use of a drug within the last month. Data for the 1979 to 2001 period, by age groups, are shown in Table 3.2. Comparing 1979 with 1998 data (the period before the sampling redesign took effect) shows that for all ages and

for any illicit drug, lifetime use of drugs increased from 31.3% of the population in 1979 to nearly 36% in 1998. Past year use dropped from 17.5 to 10.6% of the population, and current use (in the past month) dropped from 14.1% to 6.2% in this period. Results between 1999 and 2001 indicate a change in this pattern: drug prevalence showed an increase in the more recent period—most likely because incidence of drug use went up in the early 1990s and was now beginning to be mirrored in prevalence after a lag in time.

Looking at results for the 1999-2001 period, the biggest increases in current use were among those aged eighteen to twenty-five, up 2.4%, and the next highest increase was among those aged twenty-six to thirty-four, up two percentage points. Respondents aged twelve to seventeen had an increase of 1% between 1999 and 2001, and those aged thirty-five and older the lowest increase, at 0.1%. Looking back at the previous five years (1993 to 1998), the age group leading growth was the youngest, increasing in current use from 5.7 to 9.9%, up 4.2%; next were those aged eighteen to twenty-five, up 2.5% from 13.6% in 1993 to 16.1% in 1998. Those aged twenty-six to thirty-four saw a decline of 2.5 points from 9.5% to 7%. Those in the oldest group registered a small increase of 0.3%.

Figure 3.3 shows current drug use by age group for 2003. Those aged eighteen to twenty reported the highest current illicit drug use, at 23.3%, followed by those in the sixteen to seventeen age range, at 19.2%, and those in the twenty-one to twenty-five range, at 18.3%. Table 3.3 and Table 3.4 show that illicit drug use among persons aged twelve and over continued to increase in 2002 and 2003, both in terms of total number and percentage. In 2003, 46.4% of respondents reported that they had used some illicit drug in their lifetime.

Current use prevalence patterns for "any illicit drug" and for marijuana, cocaine, and heroin are shown in Figure 3.4, with more recent data in percentage terms shown in Figure 3.5. While current use of all drugs generally decreased from 1979 forward, cocaine's prevalence rose after 1979 and reached a peak in 1985, two years after it had reached its "first use" peak. SAMHSA does not claim hard-and-fast correlations between incidence and prevalence, but the agency points out that peaks in prevalence tend to follow peaks in incidence by some two or three years.

In 1979, 25.4 million people aged twelve years and older were using drugs. (See Figure 3.4.) The lowest point was reached in 1992, when current users dropped to twelve million individuals. By 2003, current users had increased substantially again to about 19.5 million. (See Table 3.3.) Expressed as percentages of the total population, these numbers were 14.1% in 1979, 5.8% in 1992, and 8.2% in 2003, according to SAMHSA. Current use rises and falls as a percentage of population, but lifetime usage has simply increased over the years. SAMHSA reports that in 1979, 70.2 million people had used drugs in their lifetime (31.3% of the 1979 population). In 2003, more than 110 million people had used a drug sometime in their lives (46.4% of the 2003 population).

Any Illicit Drug

By age group in 2003, eighteen- to twenty-five-year-olds used drugs more than any other age group—in their lifetime, in the past year, and in the past month. (See Table 3.5.) Next came those aged twelve to seventeen in all categories except lifetime. The twenty-six and older age group had the second-highest proportion of lifetime use and the lowest past year and current usage. Males consistently outnumber females among drug users. In lifetime usage, the difference is 9.3 points: 51.2% of males but only 41.9% of females had used drugs in their lifetimes in 2003. Among racial categories, the largest user group was American Indians or Alaska Natives: 62.4% of this group had used drugs in their lifetimes. Those reporting being of more than one race were second (60.1% lifetime use). More whites (49.2%) than African-Americans (44.6%) reported ever having used drugs. For use within the last year, that pattern has now reversed: 14.9% of whites and 15.4% of African-Americans reported use. For current use (within the last month), slightly more African-Americans (8.7%) had used drugs than whites (8.3%). Nearly all of these percentages are higher than they were reported two years earlier by SAMHSA.

Drug-by-Drug

The SAMHSA definition of "any illicit drug" covers quite a variety of substances. In terms of prevalence of current use, the most used drug category in 2003 was marijuana and hashish, which 14.6 million people had used in the previous month. (See Table 3.3.) Nearly 4.7 million people took prescription-type pain relievers in nonmedical applications in the previous month. In 2003 another 1.8 million abused tranquilizers in the past month. (Figure 3.6 outlines the number of lifetime nonmedical users taking various brands of pain relievers in 2002 and 2003.) Current cocaine users numbered nearly 2.3 million in 2003; of those, 604,000 smoked crack cocaine. In both cases, cocaine use was up well over the 2000 levels reported by SAMHSA. Hallucinogens represented the next most frequently used illegal drug, listed as currently used by just over one million people in 2003. Ecstasy accounted for nearly half of those users.

Also within that category, 133,000 people used LSD in 2003—up slightly from the previous year—and PCP users remained stable at about 56,000 users. Heroin was currently used by the smallest number of people, 119,000 in 2003, declining from 166,000 users in 2002. In both years, users represented 0.1% of the population, or one in a thousand. (See Table 3.4.)

Marijuana

Marijuana remains the most commonly used illicit substance in the United States. It was used by slightly more than 75% of current illicit drug users—either alone or with another illicit drug in 2003. (See Figure 3.7.) Marijuana is almost always smoked in the form of hand-rolled cigarettes or in pipes. Occasionally it is ingested.

Well over a third of the population twelve or older has used marijuana at least once. (See Table 3.4.) In 2003, 40.6%, or 96.6 million people, had used it at least once in their lifetime. The statistics on marijuana mirror those for "any illicit drug" because marijuana is the most commonly used illegal drug and dominates the survey numbers. Use of the plant has been increasing again. Among current users of any illicit drug, more than 1.6 million more people told SAMHSA in 2003 that they had used marijuana in their lifetime than had done so the year before. (See Table 3.3.) SAMHSA reports that African-Americans and whites used marijuana in similar percentages in the last month, but more whites had smoked pot in their lifetimes than African-Americans. Marijuana was least used by Asians and those of Hispanic origin.

Cocaine

Cocaine is usually sniffed or "snorted." The drug enters the body through the mucous membranes of the nose. It can also be injected or smoked, and it is some-times used in conjunction with other drugs. The most popular and notorious combination of cocaine and another illegal drug is the "speedball," a dangerous mixture of heroin and cocaine. Crack is a purified, smokable form of cocaine obtained by chemical processing. Its low prices (generally about $5 to $10 per dose) have made this form of cocaine available to all segments of the American population. According to SAMHSA, about a fifth of all consumers of cocaine in 2003 smoked crack.

The costs of powdered cocaine and the dangers associated with crack have restricted lifetime use of the drug to 14.7% of the population (34.9 million people in 2003). (See Table 3.3 and Table 3.4.) Current users, some 2.3 million individuals, were two-thirds male according to SAMHSA's 2003 survey. Overall, 1% of those surveyed had used cocaine in the previous month. Those eighteen to twenty-five had the highest current usage rate for cocaine.

Heroin

As shown in Table 3.3, in 2003, 119,000 individuals were current users and 3.7 million reported having used heroin at least once in their lifetime. SAMHSA has not provided additional data on heroin users comparable to those shown for other drugs since 1998—in part because data on such users became less reliable using the new sampling techniques. Even before the methodological change, heroin use was underreported, according to SAMHSA, because users, especially current users, are disinclined to talk to surveyors. Data for 1998 indicate (NHSDA 1998, Rockville, MD: SAMHSA, 2000) that a higher percentage of African-Americans had used heroin in their lifetime (1.9%) than whites (1%). Data for use of heroin in the past year was 0.1% of whites and 0.2% of African-Americans. In nearly all other drug categories, a higher percentage of whites used drugs than African-Americans. The highest percentage of current users of heroin were those aged eighteen to twenty-five. Males were 60% of all users.

Hallucinogens, Inhalants, and Psychotherapeutics

About 3.9 million people used hallucinogens in the past year in 2003, down from 4.7 million in 2002. (See Figure 3.8.) Most, according to SAMHSA, were in the youth category dominated by the eighteen- to twenty-five-year segment. American Indians/Alaska Natives generally showed the highest usage measured in percentage, while Asians were usually least involved in use of these drugs.

Lifetime inhalant use leveled off at 9.7% in 2003 (see Table 3.4), after increasing from 7.5% to 8.1% of the population from 2000 to 2001, according to SAMHSA. Whites were more likely to have used inhalants in their lifetimes than African-Americans. The largest percentages were among American Indians/Alaska Natives and those of more than one race. Past year inhalant use also remained stable between 2002 and 2003, at 0.9%. Among those using inhalants currently, the leading age group was the youngest (twelve to seventeen).

In 2003 some 6.3 million individuals had used prescription medicines in the past month for other than medical purposes (see Table 3.3), those in the eighteen to twenty-five age group more predominantly than those younger or older. In this single category of drug use, female participation in current use was nearly the same as the male, according to the 2003 SAMHSA report. For "any illicit drug" in 2003 (current use) females were far less likely than males to participate—6.5%, compared to 10% for males. (See Table 3.5.)

TRENDS IN DRUG EMERGENCIES

Under Section 505 of the Public Health Services Act, SAMHSA is required to collect data on drug episodes as observed in the emergency rooms of the nation's hospitals. The agency does this under a program called the Drug Abuse Warning Network (DAWN). The data collected by DAWN at six-month intervals are not considered to measure prevalence, but the sample of hospitals used has been chosen to produce what SAMHSA calls "representative estimates of E[mergency] D[epartment] drug episodes and drug mentions for the coterminous United States and for 21 metropolitan areas" (Emergency Department Trends from the Drug Abuse Warning Network, Preliminary Estimates January–June 2002, DAWN Series: D-22, DHHS Publication No. [SMA] 03-3779, Rockville, MD: SAMHSA, 2002). What DAWN counts, in other words, are the medical emergencies caused by drugs used alone or in combination. Hospitals report to DAWN the emergency room visits involving conditions of intentional drug abuse, addiction, and suicide attempts. Visits that involve chronic health conditions due to drug abuse are also included, as are intentional abuses of prescription and over-the-counter drugs. But DAWN does not include cases that are simply accidents without intentional abuse of a drug.

Patients counted in DAWN's survey usually mention more than one drug. The average is about two different drugs per visit. About a third of cases also involve the use of some drug used in combination with alcohol. Drug episodes and drug mentions are thus a way of tracking the relative importance of different drugs over time, alone or in combination, in causing distress enough to send people to the hospital. Cocaine, marijuana, heroin, and amphetamines are the leading substances DAWN classifies as "major substances of abuse." In most cases that result in death, the leading drugs as of 2002 were heroin and cocaine—usually used in combination with other drugs and alcohol.

DAWN's most recent data (in Table 3.6) provide selected drug-related emergency room visits from 1995-2002. Almost all of the selected major drugs shown display a rising involvement in episodes during this period, though in some cases the change was not statistically significant. The fastest growing hallucinogenic drug has been Ecstasy; related emergency room visits increased by 856.3% between 1995 and 2002, though they tapered off considerably in the final year of that period. Ecstasy is an unusual synthetic drug in that it combines the effects of a stimulant and of a hallucinogen. As episodes involving Ecstasy were growing, the previous leading hallucinogen in terms of emergency room visits, LSD, declined dramatically. PCP ("angel dust"), the second most important of the synthetic hallucinogens in terms of emergency room visits, has been on the rise in recent years, representing about 3,600 more emergency department visits than Ecstasy in 2002.

Marijuana mentions have nearly tripled between 1995 and 2002, a much greater increase than in mentions of cocaine and heroin. While marijuana is very often mentioned, DAWN reporting points out that a mention does not indicate that a drug is the cause of the emergency episode; in the case of marijuana, other drugs are usually also involved. In fact, there is little if any evidence that marijuana is capable at all of causing a medical emergency on its own.

Two other drugs that showed notable growth in mentions were Ketamine and GHB. GHB (gamma hydroxy butyrate) is a depressant but is known as a strength enhancer and a euphoriant. Ketamine hydrochloride is a dissociative anesthetic; it produces hallucinogenic states and impairs perception. Both drugs are synthetics known as date-rape drugs, because they can be used in incapacitating victims who are then sexually assaulted.

TRENDS IN DRUG-RELATED DEATHS

SAMHSA's DAWN program also collects data on drug-related mortality. The data are collected and published for metropolitan areas and counties. According to DAWN, its locally collected data cannot be used for national estimates of drug abuse-related mortality because, among other reasons, the samples are skewed toward urban areas and are also incomplete. National data, however, are available from the National Center for Health Statistics (NCHS), a part of the Centers for Disease Control and Prevention, an agency of the U.S. Department of Health and Human Services.

According to NCHS data, in 1979 the death rate related to drugs was 3.2 deaths per one hundred thousand of population, or 7,101 total drug deaths, split about evenly by gender. (See Table 3.7.) The death rate and total deaths have been climbing steadily since 1980,

reaching a record high of 7.2 deaths per one hundred thousand in 2001, an increase of 125%. The total number of drug deaths that year was 21,683.

NCHS death rate measurements are not exclusively restricted to the use of illegal drugs or the use of legal drugs in nonmedical applications. NCHS data also include accidental poisonings and assaults by drugs. The anthrax poisoning deaths of late 2001, for instance, would be included, but documented murders by poisoning would not. The inclusion of accidents and chemical assaults where intent is unknown somewhat weaken the data for tracking drug abuse trends, but the majority of cases are related to the use of drugs.

Another possible explanation for sharply rising drug-related deaths is the increasing use of dangerous new synthetic drugs. Along with heroin and cocaine, death rates are often related to use of the new synthetics, or combinations of these, as shown for instance by DAWN's mortality survey, (Mortality Data from the Drug Abuse Warning Network, 2002, Rockville, MD: SAMHSA, January 2004).

According to the above DAWN report, drug-related deaths, more narrowly construed and excluding accidental deaths or "assaults," consist of deaths said to be induced by one or more drugs in combination and of deaths that are said to be drug-related. In the first case, the person dies of an overdose, for instance; in the second, the drug may be responsible for a terminal medical condition, may have made the individual reckless, or may have brought the person to a psychological state that led to suicide. In the 2002 DAWN mortality survey, in twenty-five out of the thirty-one metropolitan areas studied, drug-induced deaths, such as overdoses, accounted for the majority of the drug-related deaths reported to DAWN. Deaths reported to DAWN, however, are not limited to drug overdoses. Reports also include deaths in which drug abuse was a contributing factor, but not the primary cause. In six of the thirty-one metropolitan areas (Birmingham, Buffalo, Kansas City, Miami, Omaha, and St. Louis), drug-related deaths were more commonly reported than drug-induced deaths.