An epidemiologic, clinical, and family study of simple schizophrenia in County Roscommon, Ireland

Abstract

OBJECTIVE: The authors sought to estimate the prevalence of simple schizophrenia, compare the clinical presentations and courses of simple and "typical" schizophrenia, and examine psychopathology in first- degree relatives of probands with simple schizophrenia, probands with typical schizophrenia, and community comparison subjects. METHOD: The authors followed up all individuals with a recorded diagnosis of schizophrenia (N = 285) and 75% of those with a diagnosis of severe affective illness (N = 99) from the Roscommon County Case Register, which includes all individuals seeking psychiatric care in a rural county in western Ireland. The authors interviewed all available first- degree relatives of these groups and of matched unscreened community comparison subjects. RESULTS: Eleven cases of simple schizophrenia were diagnosed in the probands, for an estimated population prevalence and morbid risk in County Roscommon of 5.3 (SE = 1.6) and 6.2 (SE = 1.9) per 10,000, respectively. Individuals with typical sch...