Real-World Evidence and Outcomes Associated with Pharmacotherapy in Schizophrenia

Schizophrenia is a severe psychiatric disorder characterized by relapse, substantial functional decline, prominent comorbidity, and increased mortality. The burden of illness is disproportional to the relatively low prevalence of schizophrenia globally. Though having a prevalence of less than 1% in most countries, schizophrenia represents one of the top causes of disability worldwide and is particularly onerous due to the early onset in late adolescence or early adulthood. Indirect costs involving loss of productivity comprise three-fourths of the total economic burden. Considerable humanistic burden is incurred by lower health-related quality of life for persons with schizophrenia compared to the overall population. Schizophrenia symptoms are categorized as positive (e.g., hallucinations, delusions, conceptual disorganization), negative (e.g., lack of emotion, lack of motivation), and cognitive (e.g., impaired attention). The disease course is relapsing-remitting with clinical periods of acute psychosis treatment and periods of maintenance therapy. While the exact causes of schizophrenia are unknown, much of the understood pathophysiology involves inappropriate signaling of the neurotransmitter dopamine. Antipsychotic medications, constituted predominately of dopamine antagonists/partial agonists, are indicated for the treatment of schizophrenia and are recommended to be continued indefinitely. Both first-generation and second-generation antipsychotics are associated with a substantial side effect burden, often leading to issues of adherence and persistence. Non-adherence is one of the strongest predictors of schizophrenia relapse. Real-world evidence provides information on patterns of care, adherence, and non-experimentally controlled conditions of use. In the case of antipsychotic medication therapy, real-world evidence can help inform patients, providers, and payers on relevant outcomes and help differentiate between agents and formulations.