Friday, August 29, 2008

I Learned Nothing by Reading This

Here is a really good article (sarcasm) on the lame antidepressant and suicide controversy (1). However, there is some misleading information that needs clarification. The article begins with "Antidepressants are the cornerstone of treatment of depressive disorders in health care. Their efficacy in treating depression is undisputable" (These people would disagree: 2, 3, 4, 5) Keep in mind these data are based on clinical trials submitted to the FDA. Meaning, this is not a new discovery, its been known for well over a decade. The problem is that the people who have been ranting about these data are crazy (e.g., Peter Breggin, Tom Cruise), which gives people an excuse to not listen to them.

Next, the article describes the nature of the problem. "Suicide is a significant public health issue. The World Health Organization (WHO) estimates that annually about one million people worldwide complete suicide." That's 1 person every 30 seconds (3 people just died while I wrote this paragraph).

When discussing the antidepressant clinical trials and suicide, he throws in the myth that has been propagated for years, "It is important to note that there are no completed suicides in these studies." (Not true, see 6).

The author continues, "In many western countries (e.g. Korkeila et al., 2007), increasing use of antidepressants on the national and regional level expectedly correlates with declining suicide mortality. Of course, such ecological studies do not prove that antidepressants have caused the observed decline in suicides..." So why mention it? It's meaningless. A third or fourth variable could be the reason for the decline (e.g., increased clinical attention). The use of correlations can easily create an impression that is not true. This CDC announcement (7) is an example. The problem with the use of correlations in studies like this, is that people use them in their arguments as if they have any meaning (8), which they don't (9, 10).

The author concluded the above-sentence with, "...but nevertheless, they are consistent with a positive or at worst, neutral net effect on suicides." Actually, antidepressants have been shown to not be effective in children and adolescents (11a, 11b), the age group with the strongest (but still weak) risk of suicide. The effects are not positive nor neutral, only negative. The excuse frequently used to give people poor medications is "cost-benefit." When there is no benefit, there is only costs.

"Depression is the most important single factor predisposing to suicide, and more than half of all subjects completing suicide are known to have suffered from depression." Nope. it's hopelessness (12). Depression is not a single factor. It's a cluster of signs and symptoms grouped together into a syndrome. Technically, that's multiple factors.

So what have we learned from another article on antidepressants and suicide? They don't work in children and adolescents. They have a small effect in adults. People died during the clinical trials. The increase in teen suicides is very small and not related to decreased antidepressant prescriptions. Correlations are useless. Hopelessness is the best predictor of future suicide. Wait a minute, all those above-listed facts aren't in that article? You know what? Don't read that article, you'll learn more reading this (13).

Update: PsychCentral has a word or two regarding a new study that showed decreased rates of suicide (09/03/2008)

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