Diphenhydramine-involved Fatal and Nonfatal Drug Overdoses in Tennessee, 2019-2022

BACKGROUND

Diphenhydramine (DPH), known as the brand name Benadryl, is an over-the-counter medication associated with accidental ingestion leading to nonfatal overdoses. Additionally, DPH has been used in tandem with illicit substances leading to fatal drug overdoses.

OBJECTIVE

In response to DPH being seized with illicit drugs as an adulterant, as well as its growing intentional misuse, we sought to explore its recent involvement in fatal and nonfatal drug overdoses in the state of Tennessee.

METHODS

We conducted a statewide cross-sectional study to determine the characteristics of DPH-involved fatal and nonfatal overdoses in Tennessee during 2019-2022 using data from the State Unintentional Drug Overdose Reporting System, the Electronic Surveillance System for the Early Notification of Community-based Epidemics, and the National Forensic Laboratory Information System Public Data Query System. Frequencies were generated to compare demographic characteristics, circumstances, and toxicology between fatal and nonfatal DPH-involved overdoses.

RESULTS

We identified 143 suspected nonfatal DPH and 409 fatal DPH-involved overdoses in Tennessee from 2019 to 2022. Nonfatal overdoses remained consistent while fatal overdoses peaked in 2021. Most nonfatal overdoses were under 18 (63.4%), while most fatal overdoses were between 18 and 64 years of age (95.7%). For fatal overdoses, fentanyl was the most prevalent substance on toxicology followed by prescription opioids.

CONCLUSION

Nonfatal overdoses remained consistent while fatal overdoses peaked in 2021 in Tennessee. Use of DPH among other illicit substances lends to evidence suggesting its use as an adulterant. Monitoring of DPH-involved fatal and nonfatal overdoses is critical to inform harm reduction initiatives.

Drug supply measures and drug overdose mortality in the era of fentanyl and stimulants

Background

Illicitly-manufactured fentanyl and stimulants have replaced prescription opioids as the primary contributors to fatal overdoses in the United States (US), yet the street supply of these substances is challenging to quantify. Building on the foundation of prior research on law enforcement drug reports, the present study compares publicly available forensic laboratory drug report measures to identify which measures account for the most variation in drug overdose mortality between states, within states over time, and in various demographic groups.

Methods

Drug reports from the National Forensic Laboratory Information System and drug overdose mortality rates from the Centers for Disease Control and Prevention were examined for all US states and the District of Columbia, 2013-2021 (459 state-years). State- and year- fixed effects models regressed drug overdose mortality rates (in the overall population and subpopulations by sex, age, and race/ethnicity) on various drug report measures, including rates per population and proportional shares of drug reports positive for fentanyl/fentanyl-related compounds, heroin, cocaine, methamphetamine, and xylazine.

Results

For drug overdose death rates in the overall population and nearly all subpopulations examined by sex, race/ethnicity, and age, the model including all drug report proportional measures represented the best-performing model (as identified via the lowest Akaike Information Criterion and highest within R-squared value), followed by the model including only the fentanyl/fentanyl-related compounds proportion.

Conclusions

Findings support the utility of publicly available drug report composition measures, particularly the proportion of fentanyl/fentanyl-related compounds, as predictors of drug overdose mortality in the US and in various subpopulations.

Dual public health crises: the overlap of drug overdose and firearm injury in Indianapolis, Indiana, 2018-2020

Background

Drug overdose and firearm injury are two of the United States (US) most unrelenting public health crises, both of which have been compounded by the COVID-19 pandemic. Programs and policies typically focus on each epidemic, alone, which may produce less efficient interventions if overlap does exist. The objective is to examine whether drug overdose correlates with and is associated with firearm injury at the census tract level while controlling for neighborhood characteristics.

Methods

An ecological study of census tracts in Indianapolis, Indiana from 2018 to 2020. Population rates per 100,000 and census tracts with the highest overlap of overdose and firearm injury were identified based on spatial clusters. Bivariate association between census tract characteristic and drug overdose and firearm violence rate within spatial clusters. Zero-inflated negative binominal regression was used to estimate if the drug overdose activity is associated with higher future firearm injury.

Results

In high overdose—high firearm injury census tracts, rates of firearm injury and drug overdose are two times higher compared to city wide rates. Indicators of structural disadvantage and structural racism are higher in high overdose—high firearm injury census tracts compared to city-wide averages. Drug overdoses are associated with higher rates of firearm injury in the following year (IRR: 1.004, 95% CI 1.001, 1.007, p < 0.05), adjusting for census tract characteristics and spatial dependence.

Conclusions

Drug overdose and firearm injury co-spatially concentrate within census tracts. Moreover, drug overdoses are associated with future firearm injury. Interventions to reduce firearm injuries and drug overdoses should be a co-response in high drug overdose—high firearm injury communities.