We assessed the spatiotemporal patterns of hospitalization with comorbid cancer and dementia. Using the 2013-2018 inpatient claims data for Medicare fee-for-service (FFS) beneficiaries, we calculated hospitalization rates by dividing the total admissions from individuals with the co-presence of a major cancer (breast, prostate, lung, and colorectal) and dementia diagnoses with the total counts of FFS beneficiaries aged 65 or older. We identified 22 hotspots with high hospitalization rates that showed heterogeneous spatial and temporal utilization patterns. The odds of a county being a hotspot increased significantly with the county-level percentage of dual Medicare-Medicaid beneficiaries (aOR 1.05; 95% CI: 1.04-1.07) and the prevalence of cancer (aOR 1.73; 95% CI: 1.59-1.89), while decreased significantly with increasing degree of rurality (aOR .82; 95% CI: .79-.85) and decreased yearly over time (aOR .72; 95% CI: .68-.75). The identified hotspots and factors at the county-level may help understand healthcare utilization patterns and assess resource allocation for this unique patient group.
Keywords: cancer; dementia; hospitalizations; hotspots; scan statistic; spatial epidemiology.