Monday, June 21, 2010

A thought about research on mental illness

Homeostasis is the property of systems, especially applied to biological systems, that regulates the internal environment in order to maintain stable, constant conditions. It has been suggested that the nervous system, faced with psychotropic drugs, will invoke homeostatic mechanisms that return the action of the nervous system to its pre-drugged condition. You can see that such a mechanism would be useful if for example a person with a normal brain were to accidentally ingest a substance which included a component that affected perception or brain functioning. It has been suggested that medication of people exhibiting symptoms of mental illness might trigger such homeostatic mechanisms that would over time return the brain to its pre-medicated conditions of mental illness.

The "gold standard" for assessing the safety and efficacy of a new drug is the randomized, double blind case control study. These studies are expensive and are time limited. It has been suggested that such a study of continuing medication with a psychotropic drug might show results that would, were the study continued long enough disappear due to the homeostatic systems of the nervous system. However, if the homeostatic mechanism were to require some years to function, most case-control studies would miss the effect due to early termination. Thus drugs might be approved on the basis of short term effects that would not be useful for long term use, and indeed might be counterproductive.

What do you suppose the medical profession would do if, after some years of use, such drugs were challenged? The practitioners would have experienced the short term efficacy with their patients, who would leave care or would be seen to have relapses. It seems to me that the common perception would be that the drugs were efficacious. Moreover, the group-think of the clinical community would tend to respond negatively to what it might perceive as a challenge to its common knowledge and general practice. The response of the drug companies profiting from the sale of the drugs and faced with possible liability were it proven to be of limited use or indeed capable of worsening the presenting condition can easily be imagined.

One public protection against such situations would be good medical records and systems for tracking the long term success of patients with chronic conditions receiving long term drug treatment.

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