Resurgence of Illicit Drug Use in '90s Poses Challenge for Physicians

April 1, 1998

Urging psychiatrists and other physicians to stay abreast of "what's going on in the youth culture," social psychologist Lloyd Johnston, Ph.D., explained that one of every 16 students entering high school has tried the potentially neurotoxic MDMA (Ecstasy) and among high school seniors, one-quarter are daily cigarette smokers and nearly one-third are frequent binge drinkers.

Urging psychiatrists and other physicians to stay abreast of "what's going on in the youth culture," social psychologist Lloyd Johnston, Ph.D., explained that one of every 16 students entering high school has tried the potentially neurotoxic MDMA (Ecstasy) and among high school seniors, one-quarter are daily cigarette smokers and nearly one-third are frequent binge drinkers.

Johnston, a senior research scientist at the University of Michigan, is principal investigator in the Monitoring the Future Study, an annual survey of 8th-, 10th- and 12th-grade students in 429 public and private secondary schools nationwide. The 1997 survey involved 51,000 students. Supported through research grants from the National Institute on Drug Abuse, the study has measured the extent of drug abuse among high school seniors since 1975, and among 8th- and 10th-grade students since 1991. Research scientists from the University of Michigan's Institute for Social Research, including Johnston and colleagues Jerald Bachman, Ph.D., and Patrick O'Malley, Ph.D., conduct the survey.

"It is clear that in the '90s there has been a considerable resurgence of drug use. Marijuana use, in particular, has led the increase, but there are other drugs, including ones as dangerous as heroin, which have grown in use," Johnston said. "Psychiatrists and primary care physicians, in particular, should routinely ask adolescent patients about possible substance use, including alcohol and tobacco, because the clinicians are in a unique position to intervene. They are highly credible authority figures, and kids usually trust them to keep private whatever they tell them. I think a lot of physicians don't ask kids about these things, because they are not quite sure what to do with the answers once they get them, or they may feel uncomfortable about probing into what they see as personal behavior. But substance use is health-related."

A significant number of youngsters have an active involvement with illicit drugs, according to Johnston. The survey defines illicit drug use as any use of marijuana, lysergic acid diethylamide (LSD), other hallucinogens, crack, other cocaine, heroin, or any use which is not under a physician's orders of other opiates, stimulants, barbiturates or tranquilizers.

"We know that the proportion of youngsters who have used some illicit drug in the past 30 days is about one in eight of 8th graders [13-to 14-year-olds], one in four of 10th graders, and little more than one in four of 12th graders. The drug most likely to be involved is marijuana," he said.

When asked if they had used marijuana/hashish in the past 30 days, 10.2% of 8th graders, 20.5% of 10th graders and 23.7% of 12th graders said yes. Only among the 8th graders was there a drop in use-1% from 1996 to 1997. Daily use of marijuana/hashish in the 1997 survey was reported by 1.1% of 8th graders, 3.7% of 10th graders and 5.8% of 12th graders.

Cocaine use in the 12 months preceding the survey was reported by 2.8% of 8th graders, 4.7% of 10th graders and 5.5% of 12th graders. Stimulant use for the same time period was reported by 8.1% of 8th graders, 12.1% of 10th graders and 10.2% of 12th graders.

LSD, the hallucinogen known for producing psychotic-like symptoms, has resurfaced as a major problem. Among high school seniors responding to the 1997 survey, lifetime use of LSD was 13.6%, surpassing periods of peak use during the 1970s when 9.5% to 11.3% of seniors were using the drug. Also in the 1997 survey, 3.2% of 8th graders, 6.7% of 10th graders and 8.4% of 12th graders said they had used LSD in the 12 months preceding the survey.

"For most drugs, there is an increase in use as we go up in grade level," Johnston said. "The 8th graders are closer to the initiation phases for a number of drugs, in particular, legal drugs like cigarettes and alcohol."

The drug class that runs counter to this trend is inhalants.

"Inhalants are unusual in that their prevalence of use is highest among the youngest children, going down to about age 10. That's probably because inhalants are not illegal, are either very cheap or free, and are readily accessible," Johnston said. "In fact, they have taken on the image of a kid's drug, so older teens don't want to be seen with inhalants."

In 1997, more than one in five 8th graders (21%) had used inhalants--glues, aerosols and solvents--at least once in their lives, and 11.8% used inhalants within the 12 months preceding the survey.

"The drug that surprises people most, because we see fairly similar lifetime prevalence rates [2.1% in 1997] across all three grade levels, is heroin," Johnston said. "That is probably an artifact: First, the prevalence rates are very low, and second, in eighth grade, all the kids are still in school, whereas by the 12th grade probably 15% have dropped out of school. The dropouts are the ones most likely to be involved in something as serious as heroin."

However, while the rates of heroin use in the student population are low, as might be expected, they have nevertheless risen significantly in all three grade levels during the 1990s. For example, in 1990, the lifetime prevalence of heroin use among 12th graders was 1.3%, compared to 2.1% in 1997. The rise in use may be partially attributable to the increase in snorting or smoking rather than injecting heroin, according to Johnston and his fellow researchers.

Beyond the illicit drugs, Johnston was particularly concerned about the continuing high levels of alcohol use and the increases in smoking.

Binge drinking (having five or more drinks in a row in the last two weeks) was reported by 31.3% of high school seniors, 25.1% of 10th graders and 14.5% of 8th graders.

Smoking, Johnston said, has been increasing sharply since 1991 among adolescents of all ages. Among 8th graders, the percentage smoking daily climbed from 7.2% in 1991 to 10.4% in 1996, dropping to 9.0% in 1997; among 10th graders, the percentage climbed from 12.6% in 1991 to 18.3% in 1996 dropping to 18% in 1997; and among 12th graders, the percentage climbed from 18.5% in 1991 to 24.6% in 1997.

"Cigarette smoking constitutes the single largest threat to the health and longevity of this generation of young Americans," said Johnston, "which makes the substantial increases in their smoking rates over the past five or six years of particular concern."

Asked about how the Monitoring the Future investigators monitor new illicit drugs becoming available, Johnston said, that when the drugs seem to become a problem, they are added to the list.

"There are always new drugs on scene, but some come and go very quickly. We don't try to incorporate every drug since we are working on a one-year survey cycle. We have separately monitored crack from powdered cocaine since the mid-1980s when the crack epidemic began. We added steroids in 1989," he said. Questions about the use of MDMA [Ecstasy] were added in 1996, and in the 1998 survey, questions about Rohypnol [flunitrazepam, an intermediate-acting benzodiazepine hypnotic] described by Johnston as the "date rape drug" will be added.

While availability of drugs is not necessarily a key predictor of increases and decreases in use of specific drugs, adolescents' perceptions of the harmfulness of the drugs is, Johnston said.

"Throughout the historical period of the survey [1975 to 1997], marijuana has been universally available to high school seniors, and hasn't changed in a way that could explain the changes in use at all. Availability doesn't seem to heavily impact use unless the drug is not available at all. The real changes in use tend to be more related to people's motivation to use," he said. "We know from our own studies, the degree to which young people see a drug as dangerous is an important determinant of use. Another closely related variable is the degree to which they disapprove of use, in other words, the peer group norms constraining use."

Many prevention programs, Johnston said, seem to be quite effective in influencing motivation. Generally, they use a combination of strategies which include teaching about the consequences of drug use so there is a motivation not to use, and teaching social skills, particularly through role playing, that enable young people to resist peer pressures to use drugs.

One reason for the need for continuing prevention efforts Johnston said is the phenomenon of "generational forgetting," which he implicates in the rise of drug use in the 1990s.

"One generation of young people may learn a lot about the dangers of drugs. One of the ways they learn is that they are involved in an epidemic and see it firsthand. But as they grow older, and generational replacement occurs, the newer cohorts don't necessarily know the same thing about the dangers of those drugs. Particularly if we have gotten drug use down, the newer cohorts wouldn't have learned vicariously about what happens to other people.

"Certainly, in the turnaround period of the 1990s, there has been a substantial change in the degree to which kids see a number of these drugs as less dangerous than their predecessors did. That concerns me, since the perception of dangerousness of the drug is an important deterrent to using. If we end up with a group of fairly naive kids who don't know much about drugs, and the drugs are readily accessible, the kids are likely to use them just out of curiosity," he said.

"Drug use among kids is a persistent and recurring problem--one which needs consistent and unremitting attention," Johnston added. "It is a long-term problem, which means that we must institutionalize prevention efforts so that they will be there for the long-term and for each new generation of American children."