Fentanyl epidemic hits the U.S. West Coast: Opioid-related deaths in San Francisco from 2009–2019

Opioid-use disorders have led to a nationwide epidemic of accidental overdoses in the United States. In recent years this opioid epidemic has worsened due to the increased availability of fentanyl in the illicit drug market. The increase in fentanyl-related deaths is well known on the U.S. East Coast, however, limited comprehensive information of mortality data exists from major West Coast cities.Following comprehensive medico-legal death and toxicological investigations, a retrospective cohort study was performed on all accidental opioid overdose deaths (AOOD) from 2009 - 2019 in San Francisco. The sex, age and race of decedents, location, and date and time of death were described and statistically compared by the type of opioid(s) causing death.Since 2016, fentanyl deaths started to replace heroin deaths leading to a sharp increase in fatal overdoses involving fentanyl, surpassing heroin and/or medicinal opioids by 2018. Fentanyl contributed to between 3% and 12% of deaths per year from 2009 to 2015, and between 20% and 73% per year from 2016 to 2019. White and Black males represented 91.5% of all AOOD. Age groups younger than 45 died using fentanyl and heroin significantly more often than older populations (60.7% of ≤45 vs. 40.7% of >45 year-olds, χ2p<0.001).This study shows an upward trend in fentanyl fatal accidental overdoses in recent years in a major West Coast U.S. city. These patterns appear to follow patterns seen in eastern states, albeit with an approximate 3-year delay, and may be indicative of other western populations. The described observations provide detailed demographic, chronological and toxicological information to public health and policy-making agencies for drug harm reduction measures.