Posts Tagged ‘The New York Times’

Medical Marijuana: Politics versus Science

Wednesday, November 27th, 2013
Marijuana in its raw form.

Marijuana in its raw form.

I recently read a New York Times article by Jane Brody titled "Tapping Medical Marijuana's Potential" in which she notes the long history of medical, spiritual and recreational use of the drug and mentions it contains  a multitude of chemicals (400 plus) in its raw form.  She confirmed my thought that if people are to use the drug for medical reasons, a joint or a pipe certainly isn't the optimal modality for administering it, When smoked, the number of compounds released multiplies by a factor of five (over 2,000 chemicals) and some are felt to lead to risks similar to those of tobacco.

As of November, 2013, twenty states and the District of Columbia have medical marijuana clinics; two states have even legalized its recreational use and a Gallup poll in October reported fifty-eight percent of Americans support legalizing marijuana for non-medical purposes. That's way up from the 12% in 1969 and roughly a third at the start of the 2000s who favored changing the laws concerning marijuana. Subgroups in this survey that still opposed legalization were those sixty-five and older and those who identified themselves as Republicans ( 62% of Democrats and 65% of Independents {up 12% since 2011} favored the change). Even the over sixty-five group had a considerable (+14%) increase in the last two years of those who are in favor of loosening the laws on the drug.

I'm going to stick to comments on medical marijuana, and not get into a discussion of recreational use.

Cornell University Law School's Legal Information Institute website details 21 USC § 812 Schedules of Controlled Substances. There are five levels of these drugs (or substances) and the most tightly controlled is Schedule I, drugs/substances (D/S) with a high potential for abuse and no currently accepted medical use in treatment in the United States. Additionally there is a lack of accepted safety for those D/S even if they are given under medical supervision. There's a long list of  Schedule I drugs including heroin, LSD, mescaline and GHB (the date rape drug). But marijuana is right alongside those, mostly for political, as opposed to scientific reasons.

Schedule II D/S  have a high potential for abuse, but do have a currently accepted  medical use in this country, some with and others without severe restrictions. Abuse can lead to severe psychological or physical dependence. Opium and cocaine are in Schedule II. Schedule III D/Ss have less potential for abuse, a currently accepted medical use and abuse can lead to moderate or low dependence. Amphetamine and its derivatives are in Schedule III. As you would expect, Schedule IV and V D/S have lower potential for abuse and habituation.

In 2005, the U.S. Supreme Court, discussing California's medical marijuana regulation (voted in under the 1996 Proposition 215) in  a case titled Gonzales v. Raich, issued a majority opinion that Congress had the power to prohibit local cultivation and use of marijuana in that state. They did so by case precedent under the Commerce Clause referring back to a 1942 decision about wheat farming. Justice O'Connor, Chief Justice Rehnquist and Justice Thomas dissented with Justice O'Connor writing that the Court's decision was sweeping overreach. She noted the two women who had sued the US Attorney General and the DEA were, in one case, raising a very small number of marijuana plants and, in the other case, relying on locally grown plants. Neither one was engaged in interstate commerce nor even conceivably had enough of the drug to substantially affect such. Both were acting in accordance with California law.

In 2008, an article in CMAJ, the Canadian equivalent of JAMA, reviewed safety studies on marijuana used medically and noted that short-term usage of the then existing forms of medical cannabinoids "appeared to increase the risk of non-serious adverse effects (the most common being dizziness), but not serious ones. The problem was the risks in longer-term use weren't well defined, even in that country which had been the pioneer in 2001 by legalizing medical usage of the drug.

2009 Department of Justice memorandum, directed at "Selected United States Attorneys," discussed "Investigations and Prosecutions in States Authorizing the Medical Use Of Marijuana." It firmly held to the DOJ being committed to enforcing the Controlled Substances Act (CSA) in all states, saying Congress still felt marijuana was a dangerous drug; its illegal distribution and sale was a serious crime and its sale provided gangs and cartels with oodles of money. While adhering to the CSA was still a clear priority, DOJ felt federal resources should not be expended in the pursuit of individuals who use marijuana medically in compliance of state laws.

An April, 2010 article in NEJM, written by two attorneys from the University of Maryland School of Law, mentions that the American Medical Association had recently voted for reviewing marijuana's status as a Schedule I drug. At that time, fourteen states had passed laws to allow the medical uses of the drug and over a dozen more were considering the idea. But there was very little if anything being done to "advance the development of standards" concerning dosing, packaging, potency, quality or purity issues. Experts in this country had urged reclassification to Schedule II as a means to allow rigorous testing of possible benefits, dosing and delivery means.

In early 2012, Mayo Clinic Proceedings published two articles and an editorial on Cannabis. The first article reported a case series of 98 patients with "Cannabinoid Hyperemesis." The first term meant chemicals found in marijuana and the second implies severe, persistent vomiting. The more common use of the medical term refers to the one to two percent of women who have continued, severe, nausea and vomiting during pregnancy…a condition termed hyperemesis gravidarum (gravid means pregnant).

How much THC is in this joint? Who knows?

How much THC is in this joint? Who knows?

A superb, long and detailed review by J. Michael Bostwick, MD of Mayo's Department of Psychiatry and Psychology has the intriguing title, "Blurred Boundaries: The Therapeutics and Politics of Medical Marijuana." and is available on an NIH website. It is well balanced and covers many facets of the history and pharmacology of the drug with caveats on its use in young individuals, an association with psychosis (marijuana may or may not be causative, but its use appears to have a distinctly negative effect on those already psychotic), the pros and cons of using it medically, and the currently available pharmaceutical cannabinoids.

The New York Daily News, on January 22, 2012, had an article titled "Marijuana-based drug Sativex may get FDA approval." A followup published August 14, 2013 in an industry online news source, Fierce Pharma, said the European pharmaceutical firm GW now had an American partner company working with the FDA on a Phase III trial for the drug in treating cancer pain and spasticity in multiple sclerosis patients. The oral spray has already been approved for patient use in the U.K., Canada, Denmark, Poland, Austria and Sweden. It has a mixture of THC, the psychoactive component, and cannabidiol, a non-psychoactive cannabinoid that can lessen the negative effects of THC while, potentially, offering reduced anxiety and anti-seizure effects of its own.

An October 3, 2013 article in Time Magazine's World section was titled "Canada Rolls Out a '$1 Billion" Privatized Medical Marijuana Industry." Medical marijuana has been legal in Canada for more than a decade but was strictly regulated. In a country whose population as of July, 2013, was estimated to be just over thirty-five million (versus the United States's November, 2013 estimate of 317 million), there are almost 40,000 registered medical marijuana users. The Canadian government thinks that there will be over eleven times that number by 2024 and has recently voted to shift to private companies, as opposed to Health Canada, controlling the drug's distribution by mail-order, but still under tight restrictions.

What next in the sweeping changes concerning marijuana? I'd like to see well-controlled prospective medical studies, but those can't happen until (and unless) it becomes a Schedule II drug.

 

 

 

 

Cancer Screening Part one: Incidentalomas & PSA

Monday, August 5th, 2013

I was reading the New York Times online today and noticed an important article in the Health section. A working group from the National Cancer Institute (NCI) had just published an article in the pre-print edition of JAMA that will likely change a highly significant face of medicine for many of us.

The issue is cancer diagnosis and, in many cases, over-diagnosis. Some pre-malignant conditions, in the viewpoint of this distinguished group, now come with the word cancer attached. That may lead to extensive testing, surgery or chemotherapy (or radiation therapy) and much mental anguish (and potential physical harm) for the patient involved.

Abnormalities, potentially malignant, can be discovered while scanning or even examining for something else. Dr. Peter Libby, chief of cardiovascular medicine at Brigham and Woman's Hospital in Boston, a Harvard medical school teaching facility, wrote a June 8, 2010 piece in The New York Times titled "The 'Incidentaloma' Problem with Medical Scans." A columnist for that paper had a CT scan for other reasons; a kidney mass was detected and a three-hour operation and eventually a six-inch scar ensued, yet the mass was benign. Dr. Libby's review of the medical literature with his area of expertise in mind showed that greater than eight percent of cardiovascular imaging studies revealed incidental findings that led to further medical procedures.

His conclusion was we're doing far too many CT scans.

Another physician wrote an April, 2011 piece in US News and World Report about a woman referred to him as a followup of an ER visit for abdominal pain that turned out to be viral gastritis. She too had a CT scan which showed her liver and intestines were normal, but one of her kidneys had a tiny mass, almost certainly a benign cyst. But the radiologist, while noting this lesion had all the features of something non-cancerous, covered his or her behind by saying, "Cannot rule out malignancy. Clinical correlation required." Translation: it was almost certainly nothing serious, but there was a very small chance that it might be cancer, and now it was the surgeon's job to make sure it wasn't.

But it's not just those advanced radiologic procedures, or MRIs or other tests; It's the mentality involved and that includes physical exams.

Let me give you a personal vignette. In 1969, as a second year clinical fellow in Nephrology, I went to see the Chief of Urology because of an abnormal lab test that involved my kidney function. A few questions later, he determined it was due to a diet I was on for a research project.

"But as long as you're here, Peter," he said, "I'll check your prostate."

It wasn't quite normal, a tad bigger than it should have been. He said, "You'll have a TURP (transurtheral resection of the prostate) by the time you're sixty"

He recommended I monitor my symptoms (I had none at the time) and get repeat examinations at intervals.

Well, I'm seventy-two and haven't had that surgical procedure. But what I did have, for many years, was a yearly digital prostate exam and, after 1994, a PSA (prostate specific antigen) blood test done periodically. At some point not only was the gland enlarged, but it the urologist involved thought it was also slightly asymmetric, so I had multiple biopsies, even though my PSA had consistently been less than 1.0, e.g., way below the level of concern.

All those biopsies showed benign (non-cancerous) tissue.

Now that I'm over seventy I don't ask for a PSA test, wouldn't agree with one if it were suggested and had my last digital exam of the gland several years ago.

But if I had that cancer at age 28 or 40, I would have been in real trouble. I would have been concerned about a malignancy that would likely kill me and would have welcomed any logical treatment for the disease. The NCI webpage on prostate cancer estimates nearly 240,000 new cases will be diagnosed in the United States this year and almost 30,000 men will die from that disease.

But the natural history of the tumor in most older men (>70 years old) is such that they will most likely die from something else (e.g., heart disease).

The NCI's fact sheet on the PSA test is well worth reading. An initial statement is that the higher a man's PSA level is, the more likely he has cancer of the prostate. Then the caveats begin: there are other reasons for the PSA to be elevated (I now have one of those, BPH or benign prostatic hypertrophy, an enlarged prostate). Half of all men over the age of fifty have BPH that is symptomatic with some hesitancy in starting their urine stream and/or a smaller stream.

If I had actually had cancer of the prostate at age sixty, my PSA may have been elevated. Then I would likely have had surgery to remove the tumor if it was localized to the gland and my physicians would then have periodically repeated my PSA testing to monitor if I had a recurrence of the neoplasm (a new and abnormal growth of tissue in some part of the body, especially as a characteristic of cancer).

A PSA level under 4.0 (nanograms/mililiter) was considered to be normal (my last PSA, done three years ago, was 0.7 ng/mL). In the past, if a man had a PSA level above 4.0 his physician  would have likely suggested biopsy to see if he had prostate cancer. But there are men who have that malignancy and yet have a PSA under 4.0 and, as I mentioned above, other, benign conditions can elevate the PSAwhile some medications used for BPH can lead to a lower PSA level. Only a quarter of those guys who have a prostate biopsy because of a PSA that's elevated actually have cancer of the gland.

But now there's considerable question whether PSA testing should be a routine, even though medicare and many private medical insurance plans cover a yearly screening using this test. The consensus seems to be that men should hear the pros and cons of the test before giving consent for it to be performed.

If 1,000 men in the 55 to 69 age range get screened with this test every one to four years, 100-200 will have false-positive results (no cancer, but an elevated PSA) and may have a biopsy recommended and, of course, worry about what's going on with their prostate.

One hundred ten, according to the cancer.gov website, will be diagnosed as having prostate cancer and nearly half of those will have treatment complications (The National Cancer Institute website mentions sexual dysfunction, bowel or bladder control issues and infections.)

Four to five will actually die from prostate cancer, but five of every 1,000 who don't have the screening will die from that cancer.

So the net is 1,000 have been screened to save 0-1 life.

And to further complicate things, the research done to determine what the normal upper limit of PSA is has largely been done in white men only.

So where do we go from here? There are studies being done to look at precursors of PSA, rate of change of PSA. free versus bound PSA etc.

We need  a better method to tell us if a man has a cancer or a benign prostate condition and to determine which prostate cancers are highly malignant fromt hose that are slow growing.

And all that's just one cancer-screening tool.