Purpose: To estimate the net change in the risk of diabetes in the population of patients with schizophrenia that may be attributable to the CER in this field, after adjusting for community trends in diabetes prevalence.
Method: Using data from the National Hospital Discharge Survey, we perform trend analyses for prevalence of diabetes and insulin resistance-unrelated general illnesses in patients with schizophrenia, as well as in individuals without known mental illness (control group), during three time periods: 1) CER-naïve era (1979–1994); 2) the hypothesis generation era (1995–2001), and 3) CER-rich era (2002-2006).
Result: Identical trends in the prevalence of diabetes and general illnesses are observed between the schizophrenia and the control groups during the CER naïve era. These allow us to use the trends in the control group in the later years as counterfactuals for corresponding trends in the schizophrenia group. Risk of diabetes, attributable to the use of A-APDs, grew at an increasing rate (0.7% per year, p<0.001) during 1995-2001, and by 2001, represented 33% (p=0.016) of the 10% diabetes prevalence in this population. During the CER-era, we find a break in the trend of diabetes prevalence in this population, but no such break in either the community trend in diabetes prevalence or the general illness trend among the schizophrenia population. This break translates to a potential reduction in the prevalence of diabetes in the schizophrenia population from 16% to 11% (p=0.038), which saves $1.25 billion per year.
Conclusion: CER identifying individual A-PD’s risk for diabetes appears to have curbed the A-APD attributable epidemic of diabetes in schizophrenia patients. Longer-term follow-up are necessary to confirm this positive role of CER.
Candidate for the Lee B. Lusted Student Prize Competition