Impact of negative symptoms on healthcare resource utilization and associated costs in adult outpatients with schizophrenia: a population-based study

BACKGROUND: To evaluate the prevalence and impact of negative symptoms on healthcare resources utilization and costs in patients with schizophrenia. METHODS: A retrospective study was conducted using electronic medical records from the health provider BSA (Badalona, Spain). All adult outpatients with a diagnosis of schizophrenia were followed for 12 months. Two study groups were defined by the presence or absence of negative symptoms based on the PANSS Negative Symptoms Factor (N1-N4, N6, G7 and G16). Healthcare (direct cost) and non-healthcare costs (work productivity losses) were described. An ANCOVA model was used for correction, p < 0.05. RESULTS: One thousand one hundred and twenty patients were included in the study (mean age: 46.8 ± 13.8 years; male: 58.4%). One or more negative symptoms were present in 52.5% of patients (95% CI: 49.6-55.4%). The most frequent were passive/apathetic social withdrawal and emotional withdrawal (60.5% and 49.8%, respectively). Patients with negative symptoms showed a greater mean number of comorbid conditions and pharmacological treatments. The adjusted unit healthcare cost related to the presence/absence of negative symptoms was €2,190.80 and €1,787.60 and the healthcare cost was €2,085.00 and €1,659.10, respectively; (p < 0.001). Patients with negative symptoms used more healthcare resources, mainly derived from primary care. The presence of negative symptoms was associated with being male, dyslipidemia, obesity and arterial hypertension (OR = 1.7, 1.4, 1.4 and 1.2, respectively). CONCLUSIONS: Negative symptoms are highly prevalent in adult outpatients with schizophrenia with a relevant economic impact on the healthcare system.