Characterization of Regional Poison Center Utilization Through Geospatial Mapping

Area of Science:

• Public Health
• Geospatial Analysis
• Health Services Research

Background:

• Penetrance, a measure of poison center (PC) utilization, historically reflects annual human exposure calls per 1000 persons.
• PC utilization exhibits significant variation based on sociodemographic factors and geographic location.

Purpose of the Study:

• To characterize the geospatial distribution of PC calls.
• To assess the contribution of geospatial mapping in understanding PC utilization patterns.

Main Methods:

• Retrospective analysis of 156,805 non-healthcare exposure calls from a regional PC over five years.
• Geocoding of exposure data (substance, demographics, ZIP Code) linked to US Census data (income, education, age, language).
• Spatial apportionment to census tracts and analysis using linear regression and geospatial mapping.

Main Results:

• Penetrance varied widely (0.081 - 38.47 calls/1000 persons/year).
• Higher educational attainment (>8th grade), and larger non-Hispanic Black and American Indian populations were associated with increased PC penetrance.
• Geospatial mapping revealed significant penetrance variability not identified through regression analysis, with low explanatory power (R2 = 0.054) for regression models.

Conclusions:

• PC call penetrance is influenced by sociodemographic factors, notably higher in areas with greater proportions of non-Hispanic Black or American Indian residents and higher educational attainment.
• Geospatial mapping offers a novel approach to identify previously unrecognized variations in PC utilization and potential disparities in healthcare access.
• Integrating geospatial mapping with sociodemographic data can guide the targeted allocation of PC resources to underserved communities and highlight healthcare access inequities.