Posted by SLS on April 9, 2006, at 13:20:51
In reply to Re: Drugs versus Psychotherapy - Backlash?, posted by linkadge on April 9, 2006, at 9:10:59
> Perhaps placebo responce to drugs goes down as severe depression goes up, but so does responce to active drugs.
Yes! You have just hit the target!
It seems that if one limits the study population to those who have the severest of depressions that meet DSM criteria for MDD, antidepressants look more like wonder drugs. If, on the other hand, you were to give an antidepressant to a population of people whose mood depends entirely on how they think, a biological intervention will do little to affect them. In this case, the response rate is similar to placebo. Unfortunately, antidepressant trials in the past have included subjects with a psychologicaly driven depression. That's why the placebo rate is so high. Many of these people are very susceptible to suggestion.
It is my guess that the preponderance of people with severe depression have a biological disorder while those with mild to moderate depressions are more likely to have a strong psychological component. This is why I keep questioning what we mean when we use the word "depression". People whose depression evolves from a psychogenic diathesis are far more apt to demonstrate a placebo effect because it is their expectation that they will be helped. I believe this expectation changes their outlook and therefore changes their mood. With psychogenic depressions, you can change the way you feel by changing the way you think. With biogenic depressions, this is not true. The way you think is determined by the way you feel.
It would be ideal to identify the difference between an endogenous versus an exogenous depression when choosing a treatment modality. However, things are not that simple. I believe that there is an affective spectrum within which are an array of psychobiologies. At either end of the spectrum lie people whose depressions are either entirely biological or entirely psychological. In between lie those whose depressions are driven by a mix of both biological and psychological contributions. I find this framework appealing because it works well to explain the phenomenology of depression as a syndrome rather than a single illness. I find that the inferences that can be drawn from this model explains much about what we see happening in the diagnosis and treatment of depression.
- Scott
poster:SLS
thread:629584
URL: http://www.dr-bob.org/babble/20060408/msgs/630947.html