An Examination of Seasonal Trends in Delaware Drug Overdoses, 2016-2020

To examine whether overdose deaths and related metrics-overdose calls for service to police and non-fatal overdose emergency department visits-in Delaware follow within-year (i.e., seasonal) patterns during the most recent years of the opioid epidemic (2016-2020).

We begin by providing descriptive statistics on yearly trends in overdose metrics, followed by Analysis of Variance (ANOVA) to analyze whether seasonal variations have a significant impact on the patterns of Delaware's overdose metrics while controlling for annual variations.

We find yearly variations across the three overdose-related metrics, with overdose deaths reporting the only consistent increases per year. Within-year, or seasonal, variations show the spring months have the most consistent increases in overdose deaths and overdose calls for service across years we studied. Finally, we report significant differences for all overdose metrics across years and seasons.

As in prior studies, we find significant variation in overdose-related metrics by season in Delaware.

These findings lend support to existing interventions in slowing yearly growth in overdose deaths. However, allocation of resources and interventions to specific times of the year-when overdoses are highest-may further reduce risks and harms.