Wednesday, October 11, 2006

More bad news regarding second generation antipsychotics.

The October 12, 2006 issue of The New England Journal of Medicine published an article regarding the use of the second generation antipsychotic drugs (SGAs) in the management of aggression and agitation and psychotic behavior in dementia. These drugs are widely used for this application although it is not approved (by the FDA) for that use and in fact there is a "black box" warning regarding increased risk of death in older patients with dementia.

Three drugs were compared with placebo in 421 patients in a multi center study; 1) olanzapine (Zyprexa), 2) risperidone (Risperdal) and 3)quetipine (Seroquel).

This trial differed from the typical efficacy-safety RCT done by drug companies as it looked at a "real clinical life" end point of time of discontinuing the medication because of any reason. The other primary outcome was the number of patients who had a minimal improvement a clinical behavior scale.

The authors concluded that the three drugs were more effective than placebo but the incidence of side effects limited their use. As seems to be more and more the case in clinical trials, there are so many comparisons made and often with rather arcane statistical tools it is difficult to know what to conclude. For example, Zyprexa was significantly better than placebo with the "Cox model" but not when compared with placebo with the "Hockberg adjustment" for multiple comparisons.Apparently this adjustment is an alternative to the Bonferroni technique to decrease the number of "false positives" when multiple comparisons are made. But how do you decide which technique to use-in this case the resultant answers seems 180 degrees apart.

Although the headline news- sound bites about this article may claim these drugs were useless, that characterization seems too simple.They can help control the symptoms of interest but often have to be discontinued because of side effects . Even the authors seems a bit ambivalent in their comments about the results;

"...our findings suggest that there is no large clinical benefit of treatment with atypical antipsychotic medications as compared with placebo."

They also say:

"Although the atypical antipsychotic drugs were more effective than placebo, adverse effects limited their overall effectiveness."

My take on all of this is these drugs may help a bit in the control of agitation and aggression in dementia patients but in a significant number of patients side effects lead to their discontinuation. Certaintly the exuberant enthusiasm driven in no small measure by drug company hype is waning. These drugs are not nearly as good as the efforts to promote them suggested. It would have been interesting and perhaps instructive for Haldol to have been included in the drugs that were compared in this study as for years it has been the stand by drug in difficult situations with dementia patients with aggressive behavior.

1 comment:

RDoc said...

One of my visitors asked if there is a difference between generics and brand Zoloft. I said probaly no.

Could you comment on that?