In most of the better clinical studies, a "placebo group" acts as a control. The placebo would consist of something totally inert, such as a capsule with nothing inside, or possibly with a small quantity of a sugar such as lactose.
The idea of an "active placebo" is interesting: in this case, the placebo is an agent shown not to have any beneficial or detrimental effect on the disease in question, but which clearly has side-effects.
An example would be using a tablet of Gravol (dimenhydrinate) as the "placebo". It is not an antidepressant, but it has side-effects (sedation, dry mouth, etc.). In this way, it is a more convincing placebo, since a person taking an agent which produces side effects is more likely to believe that they are taking the "active" agent. If a person is taking a placebo they strongly believe to be a placebo (since it produces no side effects) they are less likely to have any "placebo effect" response, and the whole point of the placebo control will be relatively "unblinded."
There is a body of research literature looking at using "active placebo" vs. antidepressants to treat depression.
http://www.ncbi.nlm.nih.gov/pubmed/9614471
{a 1998 meta-analysis from the British Journal of Psychiatry showing that the effect sizes of antidepressant therapy are only about half as large when compared against an active placebo, rather than an inert placebo}
http://www.ncbi.nlm.nih.gov/pubmed/14974002
{a 2004 Cochrane review with similar findings}
These results support the evidence that antidepressants work -- but they suggest that probably most of the studies overestimate how well they work, because they are measured against inert placebos in most cases.
I think that more clinical studies need to include active placebos.
I post this not to be cynical, or to discourage the use of antidepressants--as you can see from the rest of this blog, I strongly support medication trials to treat psychiatric problems--but I believe that we have to always search for the most accurate, least biased sources of information. We need to be wary of exaggerated claims about the effectiveness of anything, especially since I see in my practice that many of the treatments don't seem to work quite as well as the ads claim they should.
Thursday, March 5, 2009
Wednesday, March 4, 2009
Trazodone
Trazodone is another antidepressant introduced in the early 80's. Once again, its use was fashionable for a time, gradually faded, and at this point it is mainly used adjunctively to treat insomnia.
It is notable among antidepressant choices in not causing sexual side effects (other than the rare incidence of priapism, which is a medically dangerous, painful, abnormally sustained penile erection, which occurs in probably less than 1 in 1000).
The trouble with trazodone is that for many people, it causes too much daytime sedation. However, it can be worth a try, to treat insomnia associated with depression or antidepressant therapy, or possibly as an augmentation to treat depression or OCD.
In my experience, about 50% of people find trazodone a helpful adjuct, but the other 50% find it causes too much tiredness or dizziness the next day to be worth continuing.
Here is a literature review:
http://www.ncbi.nlm.nih.gov/pubmed/19112384
{in this 2008 study from a minor journal, trazodone was shown to increase the amount of slow-wave sleep in treating chronic insomnia}
http://www.ncbi.nlm.nih.gov/pubmed/12930437
{a 2003 urology article showing evidence that trazodone may help treat erectile dysfunction, especially at higher doses}
http://www.ncbi.nlm.nih.gov/pubmed/18978492
{a small 2008 study showing that 50-100 mg of trazodone may reduce SSRI-induced sexual dysfunction}
http://www.ncbi.nlm.nih.gov/pubmed/16968574
{a small 2006 study showing equivalence between trazodone and sertraline in treating depression over 6 weeks}
http://www.ncbi.nlm.nih.gov/pubmed/10507215
{a small 1999 study from a podiatry journal, showing that trazodone can help with painful diabetic neuropathy symptoms}
http://www.ncbi.nlm.nih.gov/pubmed/8010365
{a 1994 American Journal of Psychiatry article showing that trazodone can help with antidepressant-induced insomnia, particularly helping with overall subjective sleep quality, reducing waking in the middle of the night, and reducing early morning waking}
http://www.ncbi.nlm.nih.gov/pubmed/8988452
{this awkardly-designed 1996 study suggests that combination treatment including 100 mg of trazodone may help in treatment-resistant depression}
http://www.ncbi.nlm.nih.gov/pubmed/11518472
{this quite weak 2001 study nevertheless suggests that trazodone helps to reduce nightmares in PTSD patients}
http://www.ncbi.nlm.nih.gov/pubmed/6337131
{an early, 1983 study, of trazodone vs. imipramine for treating moderately to severely depressed outpatients. Despite the weaknesses of the study design, it did have some follow-up over 3 years, showing that trazodone works well for some people, and worked as well as imipramine overall}
http://www.ncbi.nlm.nih.gov/pubmed/18311107
{an example of a small study suggesting that adjunctive trazodone could help improve OCD symptoms. Some studies have shown no anti-OCD effect with trazodone alone, but others have shown trazodone alone to be beneficial in refractory OCD. In any case, I think the evidence base suggests that trazodone could at least be worth a try, either together with an SSRI, or even on its own.}
It is notable among antidepressant choices in not causing sexual side effects (other than the rare incidence of priapism, which is a medically dangerous, painful, abnormally sustained penile erection, which occurs in probably less than 1 in 1000).
The trouble with trazodone is that for many people, it causes too much daytime sedation. However, it can be worth a try, to treat insomnia associated with depression or antidepressant therapy, or possibly as an augmentation to treat depression or OCD.
In my experience, about 50% of people find trazodone a helpful adjuct, but the other 50% find it causes too much tiredness or dizziness the next day to be worth continuing.
Here is a literature review:
http://www.ncbi.nlm.nih.gov/pubmed/19112384
{in this 2008 study from a minor journal, trazodone was shown to increase the amount of slow-wave sleep in treating chronic insomnia}
http://www.ncbi.nlm.nih.gov/pubmed/12930437
{a 2003 urology article showing evidence that trazodone may help treat erectile dysfunction, especially at higher doses}
http://www.ncbi.nlm.nih.gov/pubmed/18978492
{a small 2008 study showing that 50-100 mg of trazodone may reduce SSRI-induced sexual dysfunction}
http://www.ncbi.nlm.nih.gov/pubmed/16968574
{a small 2006 study showing equivalence between trazodone and sertraline in treating depression over 6 weeks}
http://www.ncbi.nlm.nih.gov/pubmed/10507215
{a small 1999 study from a podiatry journal, showing that trazodone can help with painful diabetic neuropathy symptoms}
http://www.ncbi.nlm.nih.gov/pubmed/8010365
{a 1994 American Journal of Psychiatry article showing that trazodone can help with antidepressant-induced insomnia, particularly helping with overall subjective sleep quality, reducing waking in the middle of the night, and reducing early morning waking}
http://www.ncbi.nlm.nih.gov/pubmed/8988452
{this awkardly-designed 1996 study suggests that combination treatment including 100 mg of trazodone may help in treatment-resistant depression}
http://www.ncbi.nlm.nih.gov/pubmed/11518472
{this quite weak 2001 study nevertheless suggests that trazodone helps to reduce nightmares in PTSD patients}
http://www.ncbi.nlm.nih.gov/pubmed/6337131
{an early, 1983 study, of trazodone vs. imipramine for treating moderately to severely depressed outpatients. Despite the weaknesses of the study design, it did have some follow-up over 3 years, showing that trazodone works well for some people, and worked as well as imipramine overall}
http://www.ncbi.nlm.nih.gov/pubmed/18311107
{an example of a small study suggesting that adjunctive trazodone could help improve OCD symptoms. Some studies have shown no anti-OCD effect with trazodone alone, but others have shown trazodone alone to be beneficial in refractory OCD. In any case, I think the evidence base suggests that trazodone could at least be worth a try, either together with an SSRI, or even on its own.}
Irrational Numbers Metaphor
This is kind of a whimsical post, perhaps you may find it of very questionable relevance to a psychiatry blog.
I invite some input from any number theory experts out there, perhaps some of my thinking about the following subject is erroneous.
Irrational numbers are numbers which cannot be expressed as a ratio of integers. So, for example, the square root of 2 is irrational (it is approximately, but not exactly 1.414; it can be visualized as the distance diagonally across a square which has each side of length=1). The number pi (the ratio of a circle's circumference to its diameter) is irrational, approximately 3.14. The natural exponential base e is irrational, approximately 2.7. If we attempt to express an irrational number in decimal form, we can only ever get an approximation. The digits will keep on going forever, in a non-repeating fashion.
A hypothesis I have about the digit expansion of an irrational number is that the sequence represents a form of true randomness. At one point I did plot out the frequencies of digits in an expansion of pi to a million digits or so, then performed some statistical tests on this, and determined that the results are consistent with random ordering. They MUST be "random", for if they weren't, the number could not be irrational. I would invite a number theorist to show me a proof of this. My idea about randomness invites a philosophical, or mathematical, discussion, about what the meaning of true randomness really is.
But the digits of irrational numbers are calculable. That is, the millionth, or trillionth, digit, in the decimal expansion of pi, can be determined, systematically, through various algorithms. The number e can be calculated in a number of ways (this is a way I discovered as a child, playing with my calculator: take (1+1/n) multiplied by itself n times, with the calculation becoming more and more accurate as n grows larger--only perfectly accurate, though, when n reaches infinity).
So, I am claiming that the digits are calculable, yet randomly ordered. This is a seeming contradiction.
However, I believe there is no simple formula for the "nth" digit of pi. In order to get the "nth" digit, at least n arithmetic steps must be taken. That is, computational work must be done in order to do the calculation, and more computational work is required in order to reach a more precise result, which is at least linearly proportional to the level of precision desired.
Since all computational work requires energy, and there is a finite amount of energy available in the universe, let us suppose that we use all the mass-energy of the universe to perform computational work to determine as many digits of pi, for example, as is possible. (this would involve, in our thought experiment, harnessing all of the great nuclear energies from the stars, etc. to power a computational device just for this task)
Now, having generated all of these digits (I suspect there would be over 10^1000 digits generated, using all the energy of the universe efficiently for this task), we still only have an approximation to the number pi. The NEXT digits of pi are theoretically calculable, but cannot be calculated or known, because we have used all available computational energy.
Thus, we have calculable digits, which yet cannot be known, because there is not enough energy in the universe to do the calculations to know them.
There is something almost mystical about this: any sequence of digits, for example, randomly conceived in the mind, must correspond to a sequence of digits in the unknowable expansion of pi (in that realm over 10^1000 digits into the expansion), based on the laws of probability.
Something that we can prove is outside the realm of human knowledge is actually part of the ordinary daily products of our imagination.
As an added concept related to this, imagine what your entire life history would look like, translated into a sequence of digits -- perhaps this would include a few thousand pages of text, a few million images, together with the entire sequence of your genome, all transformed into a digit sequence, maybe a few trillion digits long.
It can be shown that this sequence -- an intimate representation of your identity -- must occur at some point in the decimal expansion of all irrational numbers, including pi. (suppose the sequence representing your life story is 10 trillion digits long; then the probability of your sequence occurring starting at or before the nth position in pi's expansion is 1-(1-1/(10 trillion))^n, assuming that pi's digit expansion behaves as a random sequence. With this assumption, once you are into pi's expansion by 10 trillion digits, there's a 63% chance that your sequence will have shown up (interestingly, this probability is approximately 1-1/e). And the more digits you go into pi's expansion, the more likely it is that "your" sequence will show up; this probability converges towards 100% as the number of digits approaches infinity. Actually, we could go on to say that "your" sequence actually recurs, an infinite number of times, in pi's expansion!
In our imagination, we can conceive an ideal circle, and we can imagine the ratio between its circumference and its diameter. That is pi exactly. We have imaginatively visualized something, with perfect precision, something that cannot be expressed logically with perfect precision.
There is a life lesson in this, I think. Be open to possibility. That which is seemingly impossible may require an imaginative re-framing to see that it was always in front of you, available to you, part of "ordinary" daily life. And there can be more to simple relationships than meets the eye -- dividing a circumference by a diameter yields a number which contains information paralleling all known information in the universe, including the story of yourself.
I invite some input from any number theory experts out there, perhaps some of my thinking about the following subject is erroneous.
Irrational numbers are numbers which cannot be expressed as a ratio of integers. So, for example, the square root of 2 is irrational (it is approximately, but not exactly 1.414; it can be visualized as the distance diagonally across a square which has each side of length=1). The number pi (the ratio of a circle's circumference to its diameter) is irrational, approximately 3.14. The natural exponential base e is irrational, approximately 2.7. If we attempt to express an irrational number in decimal form, we can only ever get an approximation. The digits will keep on going forever, in a non-repeating fashion.
A hypothesis I have about the digit expansion of an irrational number is that the sequence represents a form of true randomness. At one point I did plot out the frequencies of digits in an expansion of pi to a million digits or so, then performed some statistical tests on this, and determined that the results are consistent with random ordering. They MUST be "random", for if they weren't, the number could not be irrational. I would invite a number theorist to show me a proof of this. My idea about randomness invites a philosophical, or mathematical, discussion, about what the meaning of true randomness really is.
But the digits of irrational numbers are calculable. That is, the millionth, or trillionth, digit, in the decimal expansion of pi, can be determined, systematically, through various algorithms. The number e can be calculated in a number of ways (this is a way I discovered as a child, playing with my calculator: take (1+1/n) multiplied by itself n times, with the calculation becoming more and more accurate as n grows larger--only perfectly accurate, though, when n reaches infinity).
So, I am claiming that the digits are calculable, yet randomly ordered. This is a seeming contradiction.
However, I believe there is no simple formula for the "nth" digit of pi. In order to get the "nth" digit, at least n arithmetic steps must be taken. That is, computational work must be done in order to do the calculation, and more computational work is required in order to reach a more precise result, which is at least linearly proportional to the level of precision desired.
Since all computational work requires energy, and there is a finite amount of energy available in the universe, let us suppose that we use all the mass-energy of the universe to perform computational work to determine as many digits of pi, for example, as is possible. (this would involve, in our thought experiment, harnessing all of the great nuclear energies from the stars, etc. to power a computational device just for this task)
Now, having generated all of these digits (I suspect there would be over 10^1000 digits generated, using all the energy of the universe efficiently for this task), we still only have an approximation to the number pi. The NEXT digits of pi are theoretically calculable, but cannot be calculated or known, because we have used all available computational energy.
Thus, we have calculable digits, which yet cannot be known, because there is not enough energy in the universe to do the calculations to know them.
There is something almost mystical about this: any sequence of digits, for example, randomly conceived in the mind, must correspond to a sequence of digits in the unknowable expansion of pi (in that realm over 10^1000 digits into the expansion), based on the laws of probability.
Something that we can prove is outside the realm of human knowledge is actually part of the ordinary daily products of our imagination.
As an added concept related to this, imagine what your entire life history would look like, translated into a sequence of digits -- perhaps this would include a few thousand pages of text, a few million images, together with the entire sequence of your genome, all transformed into a digit sequence, maybe a few trillion digits long.
It can be shown that this sequence -- an intimate representation of your identity -- must occur at some point in the decimal expansion of all irrational numbers, including pi. (suppose the sequence representing your life story is 10 trillion digits long; then the probability of your sequence occurring starting at or before the nth position in pi's expansion is 1-(1-1/(10 trillion))^n, assuming that pi's digit expansion behaves as a random sequence. With this assumption, once you are into pi's expansion by 10 trillion digits, there's a 63% chance that your sequence will have shown up (interestingly, this probability is approximately 1-1/e). And the more digits you go into pi's expansion, the more likely it is that "your" sequence will show up; this probability converges towards 100% as the number of digits approaches infinity. Actually, we could go on to say that "your" sequence actually recurs, an infinite number of times, in pi's expansion!
In our imagination, we can conceive an ideal circle, and we can imagine the ratio between its circumference and its diameter. That is pi exactly. We have imaginatively visualized something, with perfect precision, something that cannot be expressed logically with perfect precision.
There is a life lesson in this, I think. Be open to possibility. That which is seemingly impossible may require an imaginative re-framing to see that it was always in front of you, available to you, part of "ordinary" daily life. And there can be more to simple relationships than meets the eye -- dividing a circumference by a diameter yields a number which contains information paralleling all known information in the universe, including the story of yourself.
Tuesday, March 3, 2009
Moclobemide is a Good Antidepressant
The antidepressant moclobemide is a reversible monoamine oxidase inhibitor. Once again, this is a drug that was frequently prescribed for a time, but has subsequently faded in popularity.
It was released in the late 80's; around 1990 many studies came out, comparing moclobemide with other antidepressants, including tricyclics and fluoxetine, showing that it worked just as well for treating depression. Many of these studies were published in Scandinavia. There have been very few clinical studies since then. Part of the reason may be that moclobemide was never approved in the U.S. (I do not understand why not).
Moclobemide has also been used effectively to treat social phobia.
In my opinion, it is a neglected option in treating depression. Because it has faded in popularity, it is usually tried as a third-line medication. For this reason, it is prescribed to patients who are more likely to have a more refractory depression. For this reason, it is less likely to be seen to help as much; this leads to clinicians pronouncing it ineffective, and not prescribing it. If it was prescribed as a first-line agent, I think we would see that it works pretty much as well as any other antidepressant.
Its advantages relate to the side-effect profile: its side effects in general are probably closest to placebo among all the antidepressants. And there are minimal or no sexual side effects with moclobemide, compared to the SSRI's. Here's a reference:
http://www.ncbi.nlm.nih.gov/pubmed/10974600
Other references:
http://www.ncbi.nlm.nih.gov/pubmed/17168253
{a 2006 meta-analysis showing that moclobemide works as well as SSRI's}
http://www.ncbi.nlm.nih.gov/pubmed/16702988
{a 2006 article from the British Journal of Pharmacology suggesting that moclobemide may have neuroprotective or even neurogenerative effects in the hippocampus}
http://www.ncbi.nlm.nih.gov/pubmed/12595913
{a 2003 review}
Addendum:
There was one case series study published in 2000 by Magder, Aleksic, and SH Kennedy, describing the successful use of very high-dose moclobemide in combination with lithium and/or trazodone for treatment-resistant depressed patients. The doses used were up to 1500-1650 mg/day, which is much higher than the usual maximum of 600 mg. They advocated using an MAOI diet at these doses. Moclobemide was well-tolerated, and the patients appeared to benefit over 1-2 years of follow-up. It's worth looking at this brief article in its entirety, here's a link to the abstract:
http://www.ncbi.nlm.nih.gov/pubmed/10831036
It was released in the late 80's; around 1990 many studies came out, comparing moclobemide with other antidepressants, including tricyclics and fluoxetine, showing that it worked just as well for treating depression. Many of these studies were published in Scandinavia. There have been very few clinical studies since then. Part of the reason may be that moclobemide was never approved in the U.S. (I do not understand why not).
Moclobemide has also been used effectively to treat social phobia.
In my opinion, it is a neglected option in treating depression. Because it has faded in popularity, it is usually tried as a third-line medication. For this reason, it is prescribed to patients who are more likely to have a more refractory depression. For this reason, it is less likely to be seen to help as much; this leads to clinicians pronouncing it ineffective, and not prescribing it. If it was prescribed as a first-line agent, I think we would see that it works pretty much as well as any other antidepressant.
Its advantages relate to the side-effect profile: its side effects in general are probably closest to placebo among all the antidepressants. And there are minimal or no sexual side effects with moclobemide, compared to the SSRI's. Here's a reference:
http://www.ncbi.nlm.nih.gov/pubmed/10974600
Other references:
http://www.ncbi.nlm.nih.gov/pubmed/17168253
{a 2006 meta-analysis showing that moclobemide works as well as SSRI's}
http://www.ncbi.nlm.nih.gov/pubmed/16702988
{a 2006 article from the British Journal of Pharmacology suggesting that moclobemide may have neuroprotective or even neurogenerative effects in the hippocampus}
http://www.ncbi.nlm.nih.gov/pubmed/12595913
{a 2003 review}
Addendum:
There was one case series study published in 2000 by Magder, Aleksic, and SH Kennedy, describing the successful use of very high-dose moclobemide in combination with lithium and/or trazodone for treatment-resistant depressed patients. The doses used were up to 1500-1650 mg/day, which is much higher than the usual maximum of 600 mg. They advocated using an MAOI diet at these doses. Moclobemide was well-tolerated, and the patients appeared to benefit over 1-2 years of follow-up. It's worth looking at this brief article in its entirety, here's a link to the abstract:
http://www.ncbi.nlm.nih.gov/pubmed/10831036
Volunteering Improves Mental Health
Altruistic volunteering is beneficial for mental health.
There are several mechanisms by which this could happen:
1) the experience of giving one's time and energy for another in need is an intrinsic life joy
2) there are opportunities to build new friendships, with others who also are "practicing altruists"
3) the experience may allow you to discover new aspects of yourself, in terms of skills, pleasures, ambitions, etc.
4) the structure of the volunteer experience may be a "benevolent structure" motivating action in your day, challenging depressive symptoms which might keep you inactive or alone
Here is some evidence from the literature:
http://www.ncbi.nlm.nih.gov/pubmed/18381833
{this 2008 study from a gerontology journal, shows that people in their 60's who volunteer moderately have higher levels of well-being, after controlling for variables such as educational level, physical health, etc. People who didn't volunteer, or people who volunteered "too much", had lower levels of well-being}
http://www.ncbi.nlm.nih.gov/pubmed/18321629
{a 2008 study from the London School of Economics, showing that there is a direct causal relationship between volunteering and happiness; weekly volunteering increases the likelihood of being "very happy" by 16%, independent of income level--the data also suggest that the effect is more pronounced for people who volunteer more frequently}
http://www.ncbi.nlm.nih.gov/pubmed/11467248
{a 2001 study looking at data from 2681 people, showing that volunteering is associated with increased well-being in numerous domains, including happiness, life satisfaction, self-esteem, sense of control over life, physical health, and depression}
http://www.ncbi.nlm.nih.gov/pubmed/9718488
{a 1998 study showing that volunteering bolsters well-being in elderly persons who volunteer; also the people who are helped by the volunteers had reduced amounts of depression}
I think there should be some more prospective, randomized studies of volunteering and other altruistic activity in the treatment of mental illnesses.
If you are interested in volunteering in Vancouver, here is a place to start looking:
http://www.govolunteer.ca/cgi-bin/page.cgi?_id=16
There are several mechanisms by which this could happen:
1) the experience of giving one's time and energy for another in need is an intrinsic life joy
2) there are opportunities to build new friendships, with others who also are "practicing altruists"
3) the experience may allow you to discover new aspects of yourself, in terms of skills, pleasures, ambitions, etc.
4) the structure of the volunteer experience may be a "benevolent structure" motivating action in your day, challenging depressive symptoms which might keep you inactive or alone
Here is some evidence from the literature:
http://www.ncbi.nlm.nih.gov/pubmed/18381833
{this 2008 study from a gerontology journal, shows that people in their 60's who volunteer moderately have higher levels of well-being, after controlling for variables such as educational level, physical health, etc. People who didn't volunteer, or people who volunteered "too much", had lower levels of well-being}
http://www.ncbi.nlm.nih.gov/pubmed/18321629
{a 2008 study from the London School of Economics, showing that there is a direct causal relationship between volunteering and happiness; weekly volunteering increases the likelihood of being "very happy" by 16%, independent of income level--the data also suggest that the effect is more pronounced for people who volunteer more frequently}
http://www.ncbi.nlm.nih.gov/pubmed/11467248
{a 2001 study looking at data from 2681 people, showing that volunteering is associated with increased well-being in numerous domains, including happiness, life satisfaction, self-esteem, sense of control over life, physical health, and depression}
http://www.ncbi.nlm.nih.gov/pubmed/9718488
{a 1998 study showing that volunteering bolsters well-being in elderly persons who volunteer; also the people who are helped by the volunteers had reduced amounts of depression}
I think there should be some more prospective, randomized studies of volunteering and other altruistic activity in the treatment of mental illnesses.
If you are interested in volunteering in Vancouver, here is a place to start looking:
http://www.govolunteer.ca/cgi-bin/page.cgi?_id=16
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