ANN ARBOR, Mich.—Eighth, 10th and 12th grade students across the country are continuing to show a gradual decline in the proportions reporting use of illicit drugs, according to the 33rd national survey in the Monitoring the Future series conducted by scientists at the University of Michigan's Institute for Social Research .
"The cumulative declines since recent peak levels of drug involvement in the mid-1990s are quite substantial especially among the youngest students," said U-M Distinguished Research Scientist Lloyd Johnston, the principal investigator of the study.
The proportion of 8th graders reporting use of an illicit drug at least once in the 12 months prior to the survey (called annual prevalence) was 24 percent in 1996 but has fallen to 13 percent by 2007, a drop of nearly half. The decline has been less among 10th graders, from 39 percent to 28 percent between 1997 and 2007, and least among 12th graders, a decline from the recent peak of 42 percent in 1997 to 36 percent this year.
All three grades showed some continuing decline this year in the annual prevalence of illicit drug use, though only the one-year decline in 8th grade (a drop of 1.6 percentage points) achieved statistical significance. The rates for the three grades now stand at 13 percent, 28 percent, and 36 percent.
Drugs declining in use
The drugs most responsible for this year's modest decline in illicit drug use are marijuana and various stimulant drugs, including amphetamines, Ritalin (a specific amphetamine), methamphetamine, and crystal methamphetamine.
Amphetamine use reached its recent peak in the mid-1990s among 8th and 10th graders. Since then, annual prevalence has fallen by more than one half among 8th graders to 4 percent and by one third among 10th graders to 8 percent in 2007. Amphetamine use peaked somewhat later among 12th graders, and has fallen by about one third to 8 percent in 2007. The one-year declines in amphetamine use were not large enough to reach statistical significance, but because they are generally consistent with an ongoing descending pattern, the investigators conclude that the decline is continuing. The same is true for crystal methamphetamine, which reached its lowest point this year since 1992. Its use is measured only among 12th graders, and their annual prevalence this year is 1.6 percent, down by about half from the peak year of 2002.
Annual prevalence for the three grades combined did fall significantly this year for both Ritalin and methamphetamine. Ritalin is a prescription amphetamine drug used to treat attention deficit hyperactivity disorder (ADHD). Its use outside of medical supervision was first measured in the study in 2001; it has been falling since then, with total declines of between 25 percent and 42 percent at each grade level. Today, 2-4 percent of students in these grades have abused Ritalin at least once in the prior 12 months.
Methamphetamine, often called "meth," use has been in decline since it was first measured in 1999. Annual prevalence is now down by about two thirds in all three grades from what it was in 1999. "Because this drug has such great potential for abuse and dependence, we are encouraged to see its popularity wane among teenagers," Johnston said. (Annual prevalence rates now range between 1.1 percent in 8th grade and 1.7 percent in 12th grade.)
Marijuana still remains the most widely used of all of the illicit drugs. The decline in 2007 in the annual prevalence of marijuana use among 8th graders was statistically significant, falling from 11.7 percent in 2006 to 10.3 percent in 2007. Tenth graders showed a modest continuing decline in marijuana use, which was not significant, while 12th graders showed no further change this year after a significant decline in 2006. Since the recent peak years of use reached in the mid-1990s, annual prevalence has fallen by over 40 percent among 8th graders, 30 percent among 10th graders, and nearly 20 percent among 12th graders. The prevalence rates for marijuana use in the prior year now stand at 10 percent, 25 percent, and 32 percent for grades, 8, 10, and 12, respectively.
Drugs holding steady
A number of illicit drugs showed little change this year. Many of them are at rates well below their recent peak levels of use, however. These include cocaine, crack cocaine, LSD, hallucinogens other than LSD, heroin, and most of the prescription-type psychoactive drugs used outside of medical supervision, including sedatives, tranquilizers, narcotics other than heroin, OxyContin specifically, and Vicodin specifically. (Both OxyContin and Vicodin are narcotic drugs.)
The one stimulant drug that did not show a decline this year was cocaine. Cocaine use reached a recent peak among teens in the late 1990s, declined for a year or two, and has held relatively level in recent years. Today, annual prevalence ranges between 2 percent and 5 percent in grades 8, 10, and 12.
Crack use, previously declined some in all three grades, but showed no further decline this year. Annual prevalence now ranges between 1.3 percent and 1.9 percent across the three grades; these rates are down by between a quarter and one half from what they were at their recent peaks.
LSD, once a widely used drug, had a very sharp decline in use from about 2001 to 2005. There has not been much change since then, and annual prevalence now ranges between 1.1 percent and 2.1 percent in the three grades. These rates are down from recent peak levels by about 75 percent.
Hallucinogens other than LSD, taken as a class, show much less decline in recent years than LSD; but they are still somewhat below their recent peak levels. (Psilocybin, also known as "shrooms" or "magic mushrooms," is the most widely used of these drugs today.) There was little change in their use this year. Annual prevalence ranges from 1.6 percent in 8th grade to 4.8 percent in 12th grade.
Heroin use by students in the survey is down by a third to a half from the recent peak rates seen in the mid- to late 1990s, but there was no change this year. Less than 1 percent of students in any of the three grades report any use of heroin in the prior 12 months.
While most of the illicit drugs have shown considerable declines in use over the past decade or so, most prescription psychotherapeutic drugs did not; in fact, a number of them showed steady increases in use outside of their legitimate medical use (amphetamines being the single exception). These include sedatives, tranquilizers, and narcotic drugs other than heroin (most of which are analgesics). As a result, they have become a relatively more important part of the nation's drug abuse problem. Fortunately, most of them have shown signs of leveling or even of beginning a gradual decline over the past couple of years.
Sedative use, which is reported only for 12th grade, did not reach its recent peak until 2005, when annual prevalence reached 7.2 percent. Today, it is down only slightly to 6.2 percent, with a drop of just 0.4 percentage points in 2007.
Tranquilizer use made a real comeback in the early 1990s, and the increase continued into 2001 in the upper grades. Since then use has declined somewhat in all three grades, including a further decline this year in 12th grade only, but the rates are still not far from the recent peaks. Annual prevalence ranges between 2.4 percent in 8th grade and 6.2 percent in 12th grade.
Narcotic drugs other than heroin are also reported only for 12th graders. An annual prevalence in 2007 of 9.2 percent is just barely below that reached in the recent peak year of 2004 (9.5 percent). Two specific drugs in this class, OxyContin and Vicodin, also did not show much change this year.
OxyContin use was first measured in 2002. The 2007 figures for all three grades are slightly higher than they were in 2002, but the trend lines have been somewhat erratic. For the three grades combined, there was no change in annual prevalence in the past year. Annual prevalence rates in 2007 for OxyContin use are 1.8 percent, 3.9 percent, and 5.3 percent. In other words, at least one in every twenty high school seniors has at least tried this powerful narcotic drug in the past year.
Vicodin similarly shows no systematic change in use this year, and the observed rates remain close to recent peak levels. Annual prevalence rates in 2007 are even higher than for OxyContin: 2.7 percent, 7.2 percent, and 9.6 percent in 8th, 10th, and 12th grades, respectively.
Drugs increasing in use
The only drug showing signs of an increase in use is MDMA (ecstasy). Ecstasy use among teens plummeted in the early 2000s, as concern about the consequences of use grew. However, the proportion of students seeing great risk in using this drug has been in decline for the past two or three years at all three grade levels, and use has begun to increase, at least in the upper grades.
Among 10th graders, annual prevalence has risen from a recent low of 2.4 percent in 2004 to 3.5 percent in 2007, while in 12th grade it has risen from a recent low of 3 percent in 2005 to 4.5 percent in 2007. While none of the one-year increases were statistically significant for 2007, a clear pattern of gradually rising use is discernable in the upper grades; and their cumulative increases over the past couple of years are statistically significant.
"These prevalence rates are not very high yet but there is evidence here of this drug beginning to make a comeback," Johnston said. "Young people are coming to see its use as less dangerous than did their predecessors as recently as 2004, and that is a warning signal that the increase in use may continue."
Students' disapproval of using ecstasy has also been slipping in recent years, particularly among 8th graders. The fact that 8th graders are showing the sharpest erosion in perceived risk and disapproval suggests that there may be what the investigators call a "generational forgetting" of the hazards of this drug as new cohorts of students enter adolescence and replace those who knew more about the consequences of use.
Over-the-counter cough and cold medications
Questions were introduced into the study in 2006 about the use of over-the-counter cough and cold medications taken for the purpose of getting high. Most of the drugs abused in this way contain the cough suppressant dextromethorphan as one of their active ingredients.
The rates observed in 2006 were fairly high, with annual prevalence rates of 4 percent, 5 percent, and 7 percent in grades 8, 10, and 12. This year saw no change in the lower grades (still at 4 percent and 5 percent) and a slightly lower rate at grade 12 (6 percent). (The decline at 12th grade was not statistically significant.)
"At least this problem of youth misuse of these over-the-counter medications does not seem to be getting worse but there is little evidence yet of much improvement," Johnston said.
Monitoring the Future tracked a fairly sharp increase in the use of anabolic steroids by male teens in the late 1990s, with peak levels reached in 1999 among 8th-grade males, in 2000 among 10th-grade males, and in 2001 and 2002 among 12th-grade males.
Since those peak years, the annual prevalence rate has dropped by more than half among the 8th and 10th grader males (to 1.1 percent and 1.7 percent, respectively), and by 40 percent among 12th-grade males (to 2.3 percent annual prevalence in 2007).
Over the past four-year interval, there has been an increase in the proportion of 12th-grade males—the only grade asked the question—who see great risk in trying anabolic steroids, which may help to account for the decline in use. There was also a sharp drop in 2005 in the perceived availability of these drugs, very likely due to the Anabolic Control Act of 2004, which placed 32 additional steroids into Schedule III and expanded the Drug Enforcement Agency's regulatory and enforcement authority regarding their sale and possession.
"While a number of states are considering implementing expensive programs to test student athletes for anabolic steroid use, the problem has been diminishing sharply," Johnston said. "It appears that supply control efforts, in combination with educational efforts, are having the intended effects."
Use among females is considerably lower than among males, and has also been declining since 2002 in the lower grades, and since 2004 in grade 12. In 2007 the annual prevalence of anabolic steroid use for girls ranges from 0.4 percent in 8th and 10th grades to 0.6 percent in 12th. These rates are down by about two thirds from their recent peak levels.
Trends in alcohol use
The use of alcohol by teens, like their use of many of the illicit drugs, has declined since the mid-1990s. The 30-day prevalence of alcohol use (reporting drinking an alcoholic beverage at least once in the 30 days prior to the survey) has fallen by 40 percent among 8th graders since their peak level in 1996.
The proportional declines since recent peak rates are smaller for the older students, however: about a one-fifth decline for 10th graders and about one sixth for 12th graders. All three grades showed small declines in use this year—none reaching statistical significance. Thirty-day prevalence of alcohol use now stands at 16 percent, 33 percent, and 44 percent for grades 8, 10, and 12.
The greater decline in use among 8th graders may well reflect the greater decline in their reported availability of alcohol. While there has been some decline in reported availability among the upper grades, the 8th graders have shown by far the greatest decline. In 1996, 75 percent of them thought that they could get alcohol if they wanted some, whereas by 2007 the number had fallen to 62 percent.
Self-reports of being drunk continued a long slow decline into 2007 (though one-year changes were not statistically significant this year). Again, the long-term decline was most pronounced among 8th graders—the youngest teens being surveyed.
The proportions saying that they got drunk in the prior 30 days was 5.5 percent in the 2007 survey, down by more than four tenths from what it was in 1996 (9.6 percent). The proportional declines are much smaller for the older students, with 18 percent of the 10th graders admitting to drunkenness within the month, down almost one quarter from their recent peak rate, and 29 percent of 12th graders admitting drunkenness, down only about one sixth from their peak rate in 1997. Here also, none of the one-year declines in 2007 reached significance, but all three grades showed some decline.
Cigarette smoking trends
Trends in the use of cigarettes and other tobacco products are the subject of a separate press release being issued simultaneously with the present one. (It is available on the study's Web site, www.monitoringthefuture.org.) For the sake of completeness here, it is noted that 30-day smoking rates continued a gradual decline in grades 8 and 10 in 2007—statistically significant for 8th grade only.
Monitoring the Future has been funded under a series of competing, investigator-initiated research grants from the National Institute on Drug Abuse, part of the National Institutes of Health (Grant Number RO01DA01411). Surveys of nationally representative samples of American high school seniors were begun in 1975, making the Class of 2007 the 33rd such class surveyed. Surveys of 8th and 10th graders were added to the design in 1991, making the 2007 nationally representative samples the 17th such classes surveyed. The sample sizes in 2007 are 16,495 eighth graders in 151 schools, 16,398 tenth graders in 120 schools, and 15,132 twelfth graders in 132 schools, for a total of 48,025 students in 403 secondary schools. The samples are drawn separately at each grade level to be representative of students in that grade in public and private secondary schools across the coterminous United States. Schools are selected with probability proportionate to their estimated class size.
The findings summarized here will be published in the forthcoming volume: Johnston, L. D., O'Malley, P. M., Bachman, J. G., & Schulenberg, J. E. (2008). Monitoring the Future national results on adolescent drug use: Overview of key findings, 2007 (NIH Publication No. [yet to be assigned]). Bethesda, MD: National Institute on Drug Abuse.
The content here is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute on Drug Abuse or the National Institutes of Health.