ASSOCIATIONS BETWEEN NEGATIVE, SYMPTOMS, SERVICE, USE PATTERNS, AND COSTS IN PATIENTS WITH SCHIZOPHRENIA IN FIVE EUROPEAN COUNTRIES

Object: Negative symptoms in patients with schizophrenia can adversely affect functionality and social interactions. However, the impact of negative symptoms on schizophrenia-related healthcare costs has not been well studied. We sought to examine this relationship in a European sample. Method: Data from the European Psychiatric Services: Inputs Linked to Outcome Domains and Needs (EPSILON) study (1998) were analysed. Using scores obtained on relevant items from the Brief Psychiatric Rating Scale, three measures of negative symptoms were generated for analysis: (I) a binary variable indicating the presence or absence of negative symptoms, (2) a negative symptom score reflecting the symptom severity, and (3) a negative symptom component score. Multiple regression models were used to analyse the impact of negative symptoms on the use and costs of inpatient, outpatient, and community-based services. Results are controlled for age, sex, marital status, employment status, race, education, psychiatric history, and study centre. Results: The sample comprised 404 patients from five study centres (Amsterdam, Copenhagen, London, Santander, Verona). Mean age was 41; 57% were men, 65% were single, 85% were white, 69% were living alone or with relatives, and 70% were unemployed or on a pension. Negative symptoms were present in 247 patients (61%), with the lowest incidence in Verona (49%) and the highest in Amsterdam (79%). Unadjusted data from all sites showed that negative symptoms were associated with higher total costs and costs for inpatient, day care, residential care, and community services, but with lower costs for outpatient care. After adjusting for sociodemographic and clinical variables, the only statistically significant correlation was higher total costs in patients with negative symptoms. Patterns of costs and resource use varied across and within study sites. Conclusions: Negative symptoms are associated with increased inpatient and total costs, and decreased outpatient costs. Therefore, allocating resources for the improved management of negative symptoms may reduce the overall costs of schizophrenia care. Further research would help to determine how differences in schizophrenia management between countries influenced patterns of cost associations with patient characteristics.