Objective: We assessed the potential clinical and economic impact of coronary heart disease (CHD) and diabetes arising after the use of second-generation ("atypical") antipsychotic agents for the treatment of chronic schizophrenia. We compared the use of these medications in patients with a higher risk of cardiometabolic adverse events (in a higher-risk scenario) and in patients with a lower risk (in a lower-risk scenario). Our U.S.-based analysis estimated the costs of CHD and diabetes arising from antipsychotic medication-related cardiometabolic effects.
Methods: We constructed a health economic model to predict the 5-year incidence of CHD and diabetes and associated costs after treatment. In this cost-consequence model, we used CHD risk functions derived from the Framingham Heart Study and diabetes risk functions derived from the Atherosclerosis Risk in Communities (ARIC) study. Patient characteristics and treatment effects on cardiometabolic risk factors were estimated from the Clinical Trials of Antipsychotic Treatment Effectiveness (CATIE) study. We evaluated two cost-consequence scenarios: the incidence of CHD and diabetes predicted for 1,000 patients with chronic schizophrenia in a higher-risk scenario based on data from CATIE associated with olanzapine (Zyprexa) and in a lower-risk scenario with ziprasidone (Geodon). We evaluated rates of adverse outcomes for each scenario and the cost of treatment for CHD and diabetes. All costs were reported in 2011 U.S. dollars. Because Medicaid is often the payer for patients with chronic schizophrenia, all costs in this analysis were derived from the perspective of Medicaid.
Results: Over a period of 5 years in 1,000 patients with chronic schizophrenia, the higher-risk scenario with olanzapine showed a 9% increased incidence of CHD and a 59% increased incidence of diabetes, compared with no change in treatment from baseline. By contrast, the lower-risk scenario with ziprasidone showed a 9% reduced incidence of CHD and a 10% reduced incidence of diabetes. The higher-risk scenario led to increased CHD-related costs of $83,206 and to increased diabetes-related costs of $456,399.
Conclusion: Our study underscores the importance of monitoring the established risk factors for CHD and diabetes in patients using second-generation antipsychotic drugs. Lower-risk agents from this class may lead to substantially decreased costs in the management of CHD and diabetes when compared with higher-risk agents.
Keywords: Medicaid; cardiometabolic; schizophrenia; second-generation antipsychotic agents.