Off-label use of second generation antipsychotics for post-traumatic stress disorder in the Department of Veterans Affairs: time trends and sociodemographic, comorbidity, and regional correlates

Abstract

Purpose: Second generation antipsychotics (SGAs) are widely used for post-traumatic stress disorder (PTSD), although without strong evidence base. With substantial numbers of veterans returning from Iraq/Afghanistan conflicts with PTSD, it is important to characterize the extent of SGA use and identify associated factors.

Methods: We determined time trends and patient characteristics associated with the use of SGAs in veterans with PTSD, without comorbid schizophrenia or bipolar disorders, using the Department of Veterans Affairs national administrative data 2003-2010.

Results: Among 732,085 veterans with PTSD, 27.6% received an intentional trial of an SGA in 2003-2010. The annual number treated with SGAs almost doubled (45,268 to 84,197, p < 0.001), while prescribing rates decreased (28.6% to 21.5%, p < 0.001). In multivariate analyses, African Americans (odds ratio (OR) = 1.07, 95%confidence interval (CI) = 1.06-1.09) and Hispanics (OR = 1.13, 95%CI = 1.10-1.17) were more likely to receive SGAs than Whites. Strongest clinical associations were with prior diagnosis of depression (OR = 1.96; 95%CI = 1.94-1.99), substance use disorders (OR = 1.86; 95%CI = 1.84-1.88), and other anxiety disorders (OR = 1.27; 95%CI = 1.26-1.29) (all p - < 0.0001) as well as cardiovascular risk factors. Veterans previously deployed to Iraq/Afghanistan had lower likelihood of SGA receipt. Substantial regional differences were demonstrated (South > Northeast; Midwest and West < Northeast; p < 0.0001); regional administrative units (veterans integrated service networks) contributed minimally to regional differences.

Conclusions: Post-traumatic stress disorder population growth is driving substantial increases in SGA use. Decreasing rates of the Department of Veterans Affairs prescribing may be due to integrated system-wide mechanisms (e.g., national practice guidelines), although regional variations remain prominent. These analyses provide foundational steps for identifying modifiable provider-level and organization-level determinants of SGA prescription in this growing population.

Keywords: antipsychotics; diffusion of innovations; pharmacoepidemiology; post-traumatic stress disorder.