Quantitative Measurement in Psychiatry and Personalized Medicine

 

The investigators reported that significantly more patients in the measurement- based care group than in the standard treatment group achieved response  (86.9% vs. 62.7%) and remission (73.8% vs. 28.8%). Time to response and remission were also significantly shorter with measurement-based care  (for response, 5.6 weeks compared with 11.6 weeks, and for remission, 10.2 weeks compared with 19.2 weeks). HAM-D scores decreased significantly in both groups, but the reduction was significantly greater for the measurement-based care group (217.8 compared with 213.6). The measurement-based care group had significantly more treatment adjustments (44 compared with 23) and higher antidepressant dosages from week 2 to week 24. Rates of study discontinuation, adverse effects, and concomitant medications did not differ between groups.

Though these data are compelling, we still face many challenges in gaining acceptance for the routine use of measurement in clinical psychiatric practice.

Measurement is valuable in a number of ways: contributing to the diagnostic process; establishing a baseline and symptom targets which can be tracked over time; documenting tolerability and severity/persistence of adverse effects; and providing important documentation in the medical record.  However, clinicians often resist with suggestions that it takes too much time, they do not have the appropriate instruments or training, and that their clinical judgment is just as good. This study adds important data to this discussion. At the same time, instrumentation and training do need to be facilitated and the field should address these needs.

For a discussion of therapeutic drug monitoring, let us focus on antipsychotic drugs. These are agents that work primarily through antagonism at the D2 subtype of the dopamine receptor. They have been the mainstay of the treatment of schizophrenia and related illnesses since the introduction of chlorpromazine in 1954. Over the last six decades, several dozen compounds have been introduced into clinical practice, each with its own pharmacokinetic profile, set of dosing recommendations, drug-drug interactions, and adverse effects.

Despite the challenges and complexity involved in the management of such a varied set of compounds as well as the known influence of such factors as smoking status, and the increasing focus on “personalized medicine,” most psychiatrists continue to monitor the efficacy and safety of antipsychotics through clinical observation and patient self-report, without the aid of more objective measures. Additionally, although the establishment of medication adherence remains perhaps the most important factor in the prevention of relapse for patients with schizophrenia, physicians routinely rely on information garnered through patient self-report for this purpose rather than on direct investigation through laboratory measures.