Hospice Coding and Data Conventions Contribute to Oversimplify the Presence of Dementia in Hospice

Objectives: To document how dementia diagnoses appear in hospice claims, and how these different presentations reflect different hospice utilization. The reliance in the hospice literature on primary diagnosis, in addition to the focus on decedents, may underestimate the true presence of dementia in hospice, and little is known about the health care utilization of hospice patients with dementia as a secondary or not present diagnosis. Design: Secondary data analysis of Medicare claims. Setting and Participants: Medicare beneficiaries with 2 or more dementia diagnoses from 2016 to 2018 electing hospice in 2018. Methods: Beneficiaries were classified based on the presence and position of dementia on their subset of hospice claims: primary diagnosis, secondary diagnosis, and not present. We then compared the demographics and utilization of the 3 claim-based categories of dementia beneficiaries in hospice in 2018. Results: Fewer than half of beneficiaries with a dementia diagnosis in all of their Medicare claims have dementia indicated as the primary diagnosis associated with their hospice claims, and 30% of beneficiaries did not have their diagnosed dementia appear at all on their hospice claims. Hospice length of stay and other utilization characteristics varied markedly across the 3 claim-based categories of dementia beneficiaries in hospice in 2018. Conclusions and Implications: Collectively, International Classification of Diseases, Tenth Revision (ICD-10) coding and sequencing conventions, coding practices, and research methods related to hospice claim diagnoses may unintentionally underestimate and oversimplify how dementia manifests in hospice utilization.