FanPost

The Truth About Marijuana (courtesy of the New England Journal of Medicine)

The following is from the June 5, 2014 issue of the New England Journal of Medicine -- widely regarded as the preeminant medical journal in the world. I encourage everyone to read it, but I have pasted some excerpts for you to peruse.

Teaching Topic Adverse Health Effects of Marijuana Use REVIEW ARTICLE Adverse Health Effects of Marijuana Use

N.D. Volkow and Others

CME Exam

In light of the rapidly shifting landscape regarding the legalization of marijuana for medical and recreational purposes, patients may be more likely to ask physicians about its potential adverse and beneficial effects on health.

Clinical Pearls Clinical Pearl What is the addictive potential of marijuana?

Despite some contentious discussions regarding the addictiveness of marijuana, the evidence clearly indicates that long-term marijuana use can lead to addiction. Indeed, approximately 9% of those who experiment with marijuana will become addicted (according to the criteria for dependence in theDiagnostic and Statistical Manual of Mental Disorders, 4th edition [DSM-IV]). The number goes up to about 1 in 6 among those who start using marijuana as teenagers and to 25 to 50% among those who smoke marijuana daily. According to the 2012 National Survey on Drug Use and Health, an estimated 2.7 million people 12 years of age and older met the DSM-IV criteria for dependence on marijuana. Indeed, early and regular marijuana use predicts an increased risk of marijuana addiction, which in turn predicts an increased risk of the use of other illicit drugs.

Clinical Pearl What is the effect of marijuana on brain development in young persons?

As compared with unexposed controls, adults who smoked marijuana regularly during adolescence have impaired neural connectivity (fewer fibers) in specific brain regions. These include the precuneus, a key node that is involved in functions that require a high degree of integration (e.g., alertness and self-conscious awareness), and the fimbria, an area of the hippocampus that is important in learning and memory. In addition, imaging studies in persons who use cannabis have revealed decreased activity in prefrontal regions and reduced volumes in the hippocampus. The negative effect of marijuana use on the functional connectivity of the brain is particularly prominent if use starts in adolescence or young adulthood, which may help to explain the finding of an association between frequent use of marijuana from adolescence into adulthood and significant declines in IQ.

Morning Report Questions Q. How does exposure to marijuana affect driving ability?

A. Both immediate exposure and long-term exposure to marijuana impair driving ability; marijuana is the illicit drug most frequently reported in connection with impaired driving and accidents, including fatal accidents. There is a relationship between the blood THC concentration and performance in controlled driving-simulation studies, which are a good predictor of real-world driving ability. Recent marijuana smoking and blood THC levels of 2 to 5 ng per milliliter are associated with substantial driving impairment. According to a meta-analysis, the risk of involvement in an accident increases by a factor of about 2 when a person drives directly after use of marijuana.

Q. What are the known effects of marijuana smoking on the pulmonary and cardiovascular systems?

A. The effects of long-term marijuana smoking on the risk of lung cancer are unclear. Marijuana smoking is also associated with inflammation of the large airways, increased airway resistance, and lung hyperinflation, associations that are consistent with the fact that regular marijuana smokers are more likely to report symptoms of chronic bronchitis than are nonsmokers; however, the long-term effect of low levels of marijuana exposure does not appear to be significant. The immunologic competence of the respiratory system in marijuana smokers may also be compromised, as indicated by increased rates of respiratory infections and pneumonia. Marijuana use has also been associated with vascular conditions that increase the risks of myocardial infarction, stroke, and transient ischemic attacks during marijuana intoxication.

FanPosts are written by community members. This is simply a way for community members to express opinions too long to be contained in a comment.

X
Log In Sign Up

forgot?
Log In Sign Up

Please choose a new SB Nation username and password

As part of the new SB Nation launch, prior users will need to choose a permanent username, along with a new password.

Your username will be used to login to SB Nation going forward.

I already have a Vox Media account!

Verify Vox Media account

Please login to your Vox Media account. This account will be linked to your previously existing Eater account.

Please choose a new SB Nation username and password

As part of the new SB Nation launch, prior MT authors will need to choose a new username and password.

Your username will be used to login to SB Nation going forward.

Forgot password?

We'll email you a reset link.

If you signed up using a 3rd party account like Facebook or Twitter, please login with it instead.

Forgot password?

Try another email?

Almost done,

By becoming a registered user, you are also agreeing to our Terms and confirming that you have read our Privacy Policy.

Join Big Blue View

You must be a member of Big Blue View to participate.

We have our own Community Guidelines at Big Blue View. You should read them.

Join Big Blue View

You must be a member of Big Blue View to participate.

We have our own Community Guidelines at Big Blue View. You should read them.

Spinner.vc97ec6e

Authenticating

Great!

Choose an available username to complete sign up.

In order to provide our users with a better overall experience, we ask for more information from Facebook when using it to login so that we can learn more about our audience and provide you with the best possible experience. We do not store specific user data and the sharing of it is not required to login with Facebook.

tracking_pixel_9341_tracker