Substance use and medical outcomes in those age 50 and older involving cocaine and metamfetamine reported to United States poison centers

Abstract

Context Cocaine and metamfetamine use and overdose deaths among United States adults have been increasing in recent years. We examined associations of medical outcomes with co-used opioids and other substances among cocaine, and metamfetamine exposures in people age ≥50 years (N = 9300) reported to the National Poison Data System, 2015–2021. Methods We first described increases in these exposures over time. We fitted generalized linear models for a Poisson distribution with a log link, one for cocaine exposures and the other for metamfetamine exposures, to examine associations of medical outcomes (major effects/death versus all others) with co-used other substances, controlling for exposure year and demographics. Results The number of exposures increased steadily during the seven years, but metamfetamine exposures increased more rapidly starting in 2018. One-fifth of cocaine and one-sixth of metamfetamine exposures suffered major effects/death. Co-use of prescription opioids (incident risk ratio = 2.00, 95% CI = 1.76–2.28 for cocaine; incident risk ratio = 1.62, 95% CI = 1.27–2.07 for metamfetamine), illicit fentanyl (incident risk ratio =1.88, 95% CI = 1.08–3.27 for cocaine; incident risk ratio = 2.05, 95% CI = 1.04–4.06 for metamfetamine), heroin (incident risk ratio =1.62, 95% CI = 1.37–1.90 for cocaine), or amfetamine (incident risk ratio =1.73, 95% CI = 1.28–2.33 for cocaine) was associated with a higher likelihood of major effects/death. Discussion Increases in the number of cocaine and metamfetamine exposures among older adults reported to poison centers are of concern, and so is the increased risk of major effects/death from polysubstance use, especially prescription and illicit opioids, among these illicit psychostimulant users. Conclusions Healthcare provider screening of individuals at risk of cocaine and/or metamfetamine use and psychoeducation about the dangers of these substance use are needed.