DOES FAMILIALITY PREDISPOSE TO BOTH EMERGENCE AND PERSISTENCE OF PSYCHOSIS - A FOLLOW-UP-STUDY

Background. It has been suggested that in schizophrenia an association exists between family history of schizophrenia and poor outcome on th e one hand, and family history of affective disorders and good outcome on the other. Method. We tested for associations between four-year ou tcome and familiar loading for psychotic disorders in a mixed sample o f 150 consecutively admitted patients with functional psychosis (schiz ophrenia, psychotic affective disorders, other psychotic disorders) of recent onset. For each proband, a familial loading score for (i) broa dly defined psychotic disorder, (ii) schizophrenia, and (iii) affectiv e disorder was calculated using information on relatives obtained thro ugh the Family History Research Diagnostic Criteria method and direct interviews of relatives with the Schedule for Affective Disorders and Schizophrenia. Results. In our sample of psychotic patients, familial loading for psychotic disorder predicted persistent negative symptoms over the follow-up period (OR 1.5; 95% CI 1-2.2), especially in schizo phrenia, and was also associated with more time hospitalised (P > 0.05 ), and more social disability at follow-up (P < 0.05). Greater familia l loading for schizophrenia predicted a greater likelihood of non-reco very (OR 2.2; 95% CI 1.1-4.4) and a greater likelihood to have had per sistent negative symptoms over the follow-up period (OR 1.7: 95% CI 0. 9-3.1). No association was found between outcome and familial loading for affective disorder. Conclusions. We conclude that familiar loading may be a continuous risk factor for some dimensions of clinical outco me in the functional psychoses. This suggests that there is a continuu m of genetic liability not only to the emergence of psychotic illness, but also the subsequent chronicity of the disorder.