Archive for the ‘statistical analysis’ Category

Issues with Psychiatric Drug use

Saturday, November 26th, 2011

Are drugs always the answer?

An article in the Wall Street Journal for November 16th caught my eye. My wife is a mental health therapist (the non-prescribing variety) and I knew this one would interest her. The title was “Psychiatric Drug Use Spreads: Pharmacy Data Show a Big Rise in Antipsychotic and Adult ADHD Treatments.”

She wasn’t especially surprised to hear that one in five adults were taking at least one psychiatric drug.  But as opposed to anti-anxiety drug use, both of us were struck by the comment that drugs given (and perhaps overused) for kids with ADHD are also increasingly being given to adults.

I went to the Internet to find the data. There’s an enormous company called Medco that provides pharmacy services for greater than 65 million people. I had never heard of the firm, but it’s rated number 35 of the Fortune 500 and in 2009 reported revues just under $60 billion.

Their senior psychiatrist, a Dr. David Muzina, has a great CV, working in major roles at the Cleveland Clinic from 1999 to 2009. I did note his “Summary” claimed “17 year’s of Cleveland Clinic experience as a Staff Psychiatrist,” but he graduated from medical school in 1993, presumably finished his Psychiatry residency in 1997 and then ran an inpatient psych unit at Lutheran Hospital (location unspecified) for two years.

In any case Medco, where Dr. Muzina is a Vice President, in and presumably heading their Neuroscience Therapeutic Resource Center, published an extremely interesting report titled “America’s State of Mind.” (see link below). This summarizes research on the prescriptions of greater than two million people in this country from 2001 to 2010.

The trends are stunning.

Boys and girls, men and women are all now more likely to be taking a drug used for mental health problems. Fifteen percent of adult men are on one or more of these medications and, amazingly, twenty-six percent of adult women.

In reality the ADHD drug use in adults is still comparatively uncommon (less than 2%), but NPR recently reported a severe shortage of Ritalin. Newer drugs which treat ADHD will enter the generic market in 2012; that should save patients considerable amounts of money.

The real impact is in the antidepressant arena: twenty-one percent of women 20 and over take these meds and the percent rises with age. It’s 16% of women ages 20 to 44, 23 percent of those between 45 and 64 and 24% of women over 65 years old. For men in comparable age groups the percent are 8, 11 and 13.

Then there’s regional distribution: what I call the “Middle West” and my own Mountain region have the lowest percentage on mental health drugs while Kentucky, Tennessee, Alabama and Mississippi have the highest.

So how many are actually taking their meds as prescribed? And how many are having serious side effects?

An issue raised in one of the publications is that of patients not taking prescribed dosages of their meds (if any), having increased symptoms and physicians therefore increasing their medication dosage.

Then if they do start taking the drug as prescribed....


Which study should I believe?

Wednesday, October 26th, 2011

Vitamin E has this chemical structure

I just read the recent (Oct 12, 2011) JAMA article on "Vitamin E and the Risk of Prostate Cancer." It was a long-term, prospective, randomized study of 33,533 men followed in 427 study sites in the US, Canada and Puerto Rico. The investigators were from major academic centers, Duke, the Cleveland Clinic, Brigham and Woman's Hospital (e.g., Harvard) and the National Cancer Institute among them.

This was an impressive study of the effects of Vitamin E and/or selenium versus placebo that began in 2001 with the subjects being "relatively healthy men." Seven years after it began, in September 2008, the independent data and safety monitoring committee decided that the supplements should be stopped as there had been no positive results (reduction in prostate cancer detection) and futility analysis (a statistical tool) said the results were quite likely to be negative (more cases of prostate cancer). I hadn't heard of that term and found a medical website that discussed a number of reasons for ending a study prior to the intended date. I'll paste in the URL if you want to read a one-pager on what is called "interim analysis."

In this study, though the researchers stopped giving supplements and published an article (JAMA.2009;301(1):39–51) on the results to date, which showed a higher (but not statistically significant) number of cases of  prostate cancer in the groups receiving Vitamin E, selenium or both, they also continued following the patient group.

Prostatic cancer under the microscope

The later data, though July 5, 2011, was quite impressive. There was a 17% higher incidence of prostate cancer in the group taking Vitamin E. In most scientific studies a p-value of 0.05  is felt to be significant. That translates to a probability of 5% or less that whatever happened did so by chance. If the data calculates to a p- value of 0.01, there's a 1% chance this was a random occurrence. Here, after ~eleven years the p-value for Vitamin E increasing the chance a man was diagnosed with prostate cancer was 0,008. (I'll paste in a website that explains more of this stuff if you're remotely interested).

Why all the math and statistics?

Well, for starters, a few years back a large study showed the exact opposite, but in a highly selected group: men in Finland who were smokers. Another study, done with physicians as the subjects, showed no effect on the incidence of prostate cancer. A post by a physician harshly criticized the SELECT trial as part of a lengthy defense of supplements, but made sweeping pronouncements without supplying data or references to specific articles.

I read the articles, the blog post and the new study in detail. I know that medical research projects often come to conclusions that, a few years later, are "proven" incorrect. But I think this study was carefully done, had a clear-cut purpose in mind and included a large enough group of subjects that I'm going to believe its conclusions.

Plus I'm certainly not a Finnish smoker.