FAMILIAL CONCORDANCE OF FLUVOXAMINE RESPONSE AS A TOOL FOR DIFFERENTIATING MOOD DISORDER PEDIGREES

Concordance to antidepressant response in members of the same family i s a common observation in clinical practice. However, few published da ta support this view; moreover families with affected members responde r to the same antidepressant have been poorly studied. We have analyze d 45 pairs consisting of one mood disorder fluvoxamine double-responde r proband and one first-degree relative with known outcome to fluvoxam ine treatment. Among 45 pairs 30 (67%) were concordant for good respon se to fluvoxamine. In family pedigrees of concordant pairs we found a significantly higher distribution of bipolar forms in secondary cases than in families of non concordant pairs (14.9% vs 3.9% P = 0.039) sug gesting that concordance to antidepressant therapy could select famili es with higher genetic loading. (C) 1998 Elsevier Science Ltd. All rig hts reserved.