Age at onset and outcome in schizophrenia are related to the degree of familial loading

Background Recent research suggests that high familiar loading is associate d with early onset of schizophrenia. Results concerning outcome have been c ontroversial. Method We assessed the relationship between familiar loading, age at onset and outcome in all Finnish patients with schizophrenia born between 1950 an d 1969. Patients and their first-degree relatives were identified using nat ionwide registers. Familial loading scores were calculated for schizophreni a and for combined psychotic disorders, and patients were accordingly class ified into three groups: high (n=761), intermediate (n=14247), and low fami lial loading (n=725). Linear mixed models and the Cox proportional hazard m odel were used in the analyses. Results Onset was earliest, hospitalisation longest and risk of retirement in receipt of a disability pension highest in the group with high familiar loading, with opposite extremes found in the group with low familial loadin g. Conclusions High familial loading for schizophrenia is associated with earl y onset and poor outcome of schizophrenia.