Delirium identification among older adults hospitalized while incarcerated

The rapidly growing population of older incarcerated patients is at increased risk of hospital-associated delirium as they have a high prevalence of comorbidities and face the unique process of accelerated aging. Our goal is to provide the first data available on identification of delirium via ICD-10 codes in this marginalized group; appropriate use of these codes communicates information across health systems and between clinicians. We examined 5,134 admissions of incarcerated patients over a 10-year period. Delirium was coded in 0.4%, significantly less than in the non-incarcerated population. Those diagnosed with delirium were six times more likely to have previously been identified as cognitively impaired via ICD-10 codes. Incarcerated patients experience incarceration-specific care processes that increase their risk of delirium, suggesting that the rate we found is a severe underestimation. This data supports future studies aimed at assessing the true rate of and risk factors for delirium in this underserved population.