Infective Endocarditis Hospitalizations in Kentucky, 2008-2018: Spatial and Temporal Trends

Infective endocarditis (IE) hospitalization rates have increased significantly in the last decade, primarily due to the opioid epidemic. In 2016, Kentucky (KY) ranked among the top ten states for opioid-related overdose deaths, but limited data exist on IE trends in KY.

This study seeks to examine county-level spatial and temporal trends in IE hospitalization rates in KY.

Hospital inpatient discharge data from 2008-2018 for KY residents aged 18 and older were analyzed. IE admissions and drug use status were identified using ICD-9 & 10 diagnosis codes. U.S. Census data calculated yearly IE hospitalization rates per 100,000 residents. Joinpoint regression identified periods with significant rate changes and calculated annual percent change (APC). Poisson modeling in SaTScan conducted spatiotemporal cluster analysis at the county level and calculated the relative risk (RR) of IE hospitalizations within identified clusters.

During 2008-2018, we observed 17,787 IE hospital admissions, including 3,577 associated with intravenous drug use (IDU-IE). Medicaid patients were more prevalent in the IDU-IE group compared to the non-IDU-IE group (75% vs. 15%). IDU-IE hospitalization rates increased from 1.2 to 27.3 per 100,000 residents between 2008 - 2018. Joinpoint regression for IDU-IE identified a significant upward trend from 2013-2018 with an APC of 71.3% (95% CI: 47.8, 98.5). The spatiotemporal analysis identified seven significant IE hospitalization clusters, with the largest (RR=2.06, p.

IDU-IE hospitalization rates increased significantly from 2013-2018, while non-IDU-IE rates decreased over the study period.