"Differential and differentiated psychopharmacology: methodological and clinical aspects"

A more differentiated view is required to interpret the results of psychopharmacological studies adequately and to apply results of randomised trials to individualised clinical situations. A differentiated perspective comprises genetically determined aspects and personality as well as situational and environmental factors which could explain individual differences in the efficacy and tolerability of psychotropic compounds. On the other hand, the spectrum of target parameters has to be enriched and should be differentiated to achieve a more comprehensive and clinically more relevant picture of the effects of the growing number of different psychopharmacological drugs.

So far, psychopharmacological research has often been focussing mainly or entirely on global efficacy parameters, e.g. the Hamilton Depression Scale or BPRS total scores. Despite the obligation to carry out such analyses due to requirements of the drug approving authorities there is a great need to broaden the view. Multivariate and multidimensional analyses including observations and experiments on different levels (e.g., observer ratings, self-ratings, neuropsychological tests, neurophysiology, brain imaging techniques etc.) should supplement the traditional approaches.

The differentiation of both independent and dependent variables in psychopharmacological research is necessary to achieve the desirable objective of evidence-based differential indications and recommendations, e.g. for the newer antidepressants and antipsychotics.

The introduction into the symposium (Chairmen: O. Benkert, Mainz; W. Janke, Würzburg) will delineate the questions arising from the proposed differentiation in psychopharmacology and pharmacopsychology.

The specific contributions to the symposium comprise presentations on the psychologically and genetically relevant factors which could at least partly explain the high inter-individual variability of desired and undesired effects of psychopharmacological drugs (P. Netter, Gießen). The particular importance of pharmacogenetic studies for psychopharmacology will be considered in an overview of recent findings in this field (M. Rietschel, Bonn).

The differentiated evaluation of antidepressant effects with respect to, e.g., onset of action and the role of personality dimensions as possible predictors to treatment, will be discussed. The persisting problem of response prediction will be illustrated by means of clinical data from a study on newer antidepressants. (A. Szegedi, Mainz).

According to biological hypotheses, neurophysiological parameters could contribute to a differentiation of psychopharmacological effects. The utilisation of parameters of auditory evoked potentials as markers of serotonergic neurotransmission for the prediction of the clinical response to serotonin-agonistic drugs will be presented (U. Hegerl, München).

The important aspect of the patients’ subjective evaluation of efficacy and side-effects under treatment with conventional or newer antipsychotic drugs will be taken into account (D. Naber, Hamburg).

A methodologically oriented contribution will finally outline the rationale and application of some approaches beyond the use of global scores for a differentiated evaluation of antipsychotic efficacy as assessed by observer ratings (M.J. Müller, Mainz).