Depression and Marijuana

By Miki Sofer
Source: Stanford Daily

Cannabis, pot, marijuana, weed: the aliases abound, but what can be decisively said about this well-known drug? Considering that marijuana is the most commonly used illicit substance in the United States, much ambiguity remains surrounding the relationship between this drug and its users.



Although most people associate marijuana with a happiness- or calm-inducing high, recent research has explored the relationship between depression and marijuana.

When the drug hits the brain

Chemicals in marijuana flow directly to the brain, crossing the blood-brain barrier and affecting major memory, coordination and learning centers. When someone smokes a joint, THC - the primary active chemical in marijuana - enters the bloodstream through the lungs, binds to specific receptors on nerve cells in the brain and initiates a series of cellular reactions that result in the “high” typically experienced by marijuana users.

A study involving inexperienced individuals revealed that marijuana tends to have either a neutral or negative affect on mood, whereas a study of people with depression found that THC may significantly increase unhappiness.

Although studies have not been conclusive, mounting evidence suggests marijuana use and depression occur together more often than chance would predict: Clinical studies have reported elevated depression rates among those seeking treatment for marijuana dependence, while others have found a similar association between elevated levels of marijuana use and depression treatment.

The question is, what comes first? Marijuana dependence or depression?

Teens, drugs and depression

In recent years, rising rates of marijuana use and depression among young adults have sparked concern. According to the National Institute on Drug abuse, 46.1 percent of 12th graders surveyed last year admitted to having tried marijuana at some point in their lives, a figure that has declined since the late 1990s, yet is higher than estimates from the earlier part of the decade.

Studies on teen depression have indicated that more than 20 percent of adolescents suffer from emotional problems - a third of all psychological diagnoses in teenagers are for depression. Even more disturbing is the adolescent suicide rate, which has increased by a margin of 200 percent since 1993.

Drugs or depression: Which comes first?

As a result of rising rates of depression and marijuana use, recent studies have attempted to identify a causal relationship between these two factors. At the Washington University Medical School in St. Louis, Dr. Michael T. Lynskey and his colleagues in the Psychiatry Department are researching the function of genetic and environmental variables and the relationship between early-onset marijuana use and Major Depressive Disorder (MDD).

As part of a larger investigation based in Australia, the method identified 277 twin pairs in which one had initiated marijuana use before age 17 and the other did not. By studying twins, researchers are better able to separate whether drug use and depression are caused by genetic or environmental factors, particularly if they look at the differences between identical and fraternal twins.

Lynskey's study revealed that suicidal thoughts and attempts were over twice as likely to appear in the marijuana-dependent twin.

The correlation between marijuana use and depression was higher in the fraternal pairs than in the identical pairs, demonstrating that environmental factors - family life, education, community atmosphere - may play a larger role in both drug abuse and psychological disorders than genetics.

“Because there is a difference between [identical] and [fraternal] pairs, some of the observed reactions may arise due to genetic vulnerability to marijuana abuse and environmental influence,” Lynskey explained .

The study suggested that marijuana use early on in life may not actually place people at risk for depression later on in life, although continued use may prolong or harm treatment outcome by exacerbating symptoms.

“There needs to be recognition that cannabis is not the root cause of every difficulty that people experience,” Lynskey said. “In terms of looking at complex issues like depression, we need to shy away from identifying one factor and search instead for a life course, a complex perspective.”

At the opposite end of this correlational spectrum, medical professionals have theorized that depression is the cause of marijuana use, rather than the result. That is, people who are depressed use marijuana to relieve or “escape from” their symptoms of depression. Some studies have demonstrated that marijuana improves mood and that people who are depressed during the initial stages of an experiment are more inclined to begin, continue or increase their marijuana use by the time of follow-up.

The student perspective

Do students fit this mold? Are they more likely to use marijuana when depressed?

When questioned, Stanford students rarely cited depression as a primary reason for smoking marijuana. The vast majority indicated that they smoked because they thought it was fun.

“It serves as a change of pace from drinking,” said Sean, who asked that his real name not be revealed.

“If you think about all the times that you are high or not high, you realize that you have more fun when you are high,” explained Clark, a habitual user, who also chose not to disclose his real identity.

Moreover, the students questioned said that they would never smoke by themselves unless it was in preparation for a social event.

“If you smoke by yourself, that's when it becomes more of an issue,” Clark said.

When the topic of depression did arise, it was in the context of a discussion concerning how one's mood might change after smoking.

“Smoking marijuana magnifies a lot of the feelings that you're already feeling,” Sean explained. “People tend to become very introspective, more self-critical, and from that they get the signs of depression.”

Clark reflected on the influence of marijuana on behavior.

“If I'm in a bad mood about things, it reinforces those feelings,” Clark said. “I don't smoke when I am feeling [unhappy] because that leads to problems. I do know people, however, who were depressed, tried smoking and became potheads, immediately.”

University health officials are more concerned about the rate of depression at Stanford than drug abuse cases, given that depression is a larger problem among the student population.

According to a random sampling conducted this year, approximately 17 percent of Stanford undergraduates had used marijuana in the last 30 days at the time of data collection, a number that has gone down since previous samplings, explained Ralph Castro, manager for the Alcohol and Other Drug Abuse Prevention Program at Stanford

Additionally, less than 4 percent of the undergraduates questioned were classified as “chronic” users, individuals who smoke marijuana 10 or more times a month.

“Marijuana is here on campus, but it is not epidemic,” Castro said.

Dr. Alejandro Martinez, director of Counseling and Psychological Services, CAPS, at the Vaden Student Health Center, agreed, adding that “the number of people who come in with marijuana use problems is very small.”

The connection between depression and marijuana use rates on campus remains obscure. Martinez reported that 17 percent to 22 percent of the students that CAPS counsels each year come in for help with depression. These percentages are higher than those observed in the general population, but cannot be tied statistically to the number of people who come in with substance abuse problems.

“At Stanford, depression is a more significant concern for us than marijuana use in terms of students who are seeking help,” Martinez explained.

Then again, he added, it may be hard to make this distinction since many students that smoke marijuana are unlikely to seek help for abuse problems.

Students see marijuana as a “safer” alternative to other drugs.

University health officials are concerned about the relatively nonchalant attitude that many students have assumed toward marijuana. Martinez said he thought many students would choose to smoke marijuana and not drink alcohol because they saw it as a drug with fewer health consequences.

“From the students' point of view, marijuana is not perceived as health-compromising,” he said.

Students are well aware of the dangers of smoking cigarettes, but they are less likely to be clued into the dangers of smoking marijuana.

“People at Stanford are smart to the fact that they know [smoking] kills you, but marijuana has not been proven to do so,” said Melissa, who chose not to disclose her real name.

Researchers in Lynskey's lab will continue to study the complex relationship between drugs and psychological disorders, which will allow doctors and psychiatrists to pinpoint the causes and develop appropriate prevention measures.

University officials such as Castro, meanwhile, are concerned that there has been “a shift in adolescent culture.” Extreme forms of behavior, he argued, are surfacing in a larger part of society, and people are placing themselves in more dangerous situations due to cultural pressures, which may lead to higher incidences of both drug abuse and depression in the end.

Complete Title: Depression and Marijuana: Does Smoking Pot Put You at a Higher Risk for Depression, or Does the Link Work the Other Way? Source: Stanford Daily (CA Edu)
Author: Miki Sofer
Published: Thursday, October 28, 2004
Copyright: 2004 The Stanford Daily
Website: http://daily.stanford.org/
Contact: letters@daily.stanford.edu