Abstract
Background:
Opioid-involved deaths are continuing to increase across the United States, exceeding 100,000 for the first time in 2021. Contamination with, and intentional use of, synthetic opioids such as fentanyl are a major driver of this increase. Utilizing self-report substance use data of patients being treated in the emergency department (ED) can be useful to determine which substances patients are intentionally seeking.
Objectives:
1) Examine changes in self-reported illicit substance use (including fentanyl) over time; 2) Examine changes in the co-occurrence of self-reported fentanyl with other illicit substance use over time.
Methods:
All patients presenting to the study EDs that answered anything other than “never” on the National Institute on Drug Abuse Quick Screen and were seen by a peer recovery specialist in the ED between July 1, 2020 and December 31, 2022 were included for analysis. The substance of use as reported by each patient was recorded by the peer recovery specialist. Differences in substance use by type over time were examined using chi-squared tests of proportions.
Results:
There were 7568 patients that met inclusion criteria. Self-reported fentanyl (1760%; p < 0.0001) and cocaine (82%; p = 0.034) use increased, whereas heroin use (16%; p < 0.0001) decreased.
Conclusions:
Self-reported fentanyl and cocaine use has increased significantly in South Carolina ED patients between 2020 and 2022. Given the high morbidity and mortality associated with fentanyl and fentanyl analog use, further measures to identify these patients and provide harm reduction and treatment from the ED setting are warranted.
Keywords: fentanyl, cocaine, heroin, substance use trends, self-report
Introduction
The opioid crisis in the United States is continuously evolving. Initially driven by prescription opioids, opioid-involved overdose deaths began rising in the early 2000s (1). After a reduction in opioid prescribing and an increase in availability of high purity, low-cost heroin, this initial wave was followed by a rise in heroin-involved deaths (1). Currently, the United States is in the midst of a third wave of overdose deaths largely stemming from an increase in the use of illicitly manufactured fentanyl, fentanyl analogues, and other illicit synthetic opioids (1–4). In April 2021, it was reported that the estimated number of drug overdose deaths in the United States over the previous 12-month period exceeded 100,000 for the first time (3). Most recent reports indicate that synthetic opioids are involved in approximately two-thirds of overdose deaths in the United States (4).
Substantial co-involvement of other substances in fentanyl-involved deaths has contributed to the overdose risk (3). Approximately 40% of fentanyl-involved deaths involved stimulants, including cocaine (30%) and methamphetamine (20%); 30% involved other opioids, including heroin (20%); and 15% involved benzodiazepines (3). Due to the continuously evolving nature of this epidemic, accessing non-overdose-related patient-level data is imperative for combating the opioid crisis. Relying on fatal overdose reports to monitor substance use trends is limiting due to the time lag involved with collecting postmortem toxicology testing results and death certificate reports. Emergency departments (EDs) that screen for substance use provide an opportunity to identify substance use trends within a community. Self-report can be particularly useful to determine which substances patients are intentionally seeking, rather than assessing what they received, as studies have demonstrated a significant discordance between the two (5–7). In this analysis, we examine trends in substance use self-reported by patients seeking care in eight South Carolina EDs. This analysis is intended to report real-time substance use data to inform prevention and harm reduction efforts during the ongoing opioid epidemic.
Methods
The sample included a cohort of patients that were screened, as described in Bogan et al., for substance use across eight EDs in five hospital systems in South Carolina as a component of a Screening, Brief Intervention, and Referral to Treatment and ED-initiated buprenorphine project (8). The study sites include academic medical centers, nonacademic community hospitals, and a private teaching hospital in rural and urban areas in various geographic regions of the state (e.g., Upstate, Pee Dee, Grand Strand, and Low Country). All patients that answered anything other than “never” on the National Institute on Drug Abuse Quick Screen administered by nursing at ED triage from July 1, 2020 through December 31, 2022 and were seen by a peer recovery specialist (PRS) were included for analysis (9). The PRS in the ED collected data on self-reported substance use at the time of the ED visit and entered this information into REDCap, a secure, Health Insurance Portability and Accountability Act-compliant, web-based software platform that served as the data management software (10,11). These data were collected as part of a quality improvement project and were, therefore, not considered human subject research by the Institutional Review Board of the Medical University of South Carolina. Self-reported use of amphetamine, benzodiazepine, cocaine, fentanyl, heroin, methamphetamine, and prescription opioids were included in the analysis. We counted patients who reported using multiple substances in each substance type; therefore, patients could contribute to multiple categories. We used chi-squared tests of proportions or Fisher’s exact test in the case of small sample size for pairwise comparisons of reported substances used between time points. Significance was set at a p < 0.05. Data analysis was performed using SPSS 27.0 (IBM SPSS, Armonk, NY).
Results
The total sample included 19,187 patient interactions, with 7567 (39%) screening positive for use of any substance. Demographic characteristics of individuals screening positive for substance use are shown in Table 1. These individuals were predominantly male (68%), white (75%), from the Upstate region (62%), and from an urban county (91%). The mean age was 42 ± 14 years. Almost all patients were seen at community medical centers (46%) or academic medical centers (45%). The most commonly reported substances in this patient population were methamphetamine (n = 3230), followed by heroin (n = 2243) and cocaine (n = 2075), accounting for 43%, 30%, and 27% of substance reports, respectively (Table 2 and Figure 1A).
Table 1.
Demographics of Patients Self-Reporting Illicit Substance Use in Eight South Carolina Emergency Departments July 1, 2020–December 31, 2022
| Patient Characteristics | n (%) |
|---|---|
| Age in years, Mean (SD) | 42 (14) |
| Gender | |
| Male | 5110 (68) |
| Female | 2447 (32) |
| Not listed | 10 (0) |
| Race/ethnicity | |
| White or Caucasian | 5665 (75) |
| Non-White | 1902 (25) |
| Hospital type | |
| Academic medical center | 3409 (45) |
| Community medical center | 3499 (46) |
| Private teaching hospital | 659 (9) |
| Geographic area | |
| Upstate | 2747 (62) |
| Pee Dee | 267 (4) |
| Grand Strand | 941 (12) |
| Low Country | 1635 (22) |
| Urbanicity | |
| Rural | 650 (9) |
| Urban | 6917 (91) |
Table 2.
Number of Self-Reports of Illicit Substance Use from Patients Presenting to Eight South Carolina Emergency Departments By Annual Quarter July 1, 2020 – December 31, 2022
| Annual Quarter | Total Patient Encounters | Patients Reporting Substance Use n (%)‡ | Substance Use, n* (%)† |
||||||
|---|---|---|---|---|---|---|---|---|---|
| Amphetamine | Benzodiazepine | Cocaine | Fentanyl | Heroin | Methamphetamine | Prescription Opioids | |||
| Q3 2020 | 1424 | 518 (36) | 20 (4) | 57 (11) | 125 (24) | 10 (2) | 171 (33) | 214 (41) | 69 (13) |
| Q4 2020 | 1846 | 691 (37) | 18 (3) | 67 (10) | 175 (26) | 31 (5) | 216 (31) | 292 (42) | 101 (15) |
| Q1 2021 | 1927 | 745 (39) | 27 (4) | 56 (8) | 199 (27) | 42 (6) | 232 (31) | 321 (43) | 103 (14) |
| Q2 2021 | 2264 | 891 (39) | 23 (3) | 65 (7) | 204 (23) | 55 (6) | 343 (39) | 410 (46) | 85 (10) |
| Q3 2021 | 1912 | 762 (40) | 25 (3) | 63 (8) | 194 (26) | 111 (15) | 278 (37) | 314 (41) | 87 (11) |
| Q4 2021 | 1989 | 742 (37) | 41 (6) | 80 (11) | 231 (31) | 108 (15) | 216 (30) | 298 (40) | 92 (12) |
| Q1 2022 | 1931 | 754 (39) | 23 (3) | 69 (9) | 231 (31) | 136 (18) | 228 (30) | 328 (44) | 76 (10) |
| Q2 2022 | 2108 | 876 (42) | 44 (5) | 82 (9) | 237 (27) | 161 (18) | 238 (27) | 366 (42) | 104 (12) |
| Q3 2022 | 1960 | 808 (41) | 27 (3) | 89 (11) | 251 (31) | 164 (20) | 178 (22) | 345 (43) | 99 (12) |
| Q4 2022 | 1826 | 780 (43) | 32 (4) | 71 (9) | 228 (30) | 186 (24) | 143 (18) | 342 (44) | 75 (10) |
| Total | 19,187 | 7567 (39) | 280 (4) | 699 (9) | 2075 (27) | 1004 (13) | 2243 (30) | 3230 (43) | 891 (12) |
| Q3 2020–Q4 2022, % change | 51 | 60 | 25 | 82 | 1760 | −16 | 60 | 9 | |
| p Value | < 0.001§ | 0.803 | 0.261 | 0.034§ | < 0.001§ | < 0.001§ | 0.297 | 0.037§ | |
| Q2 2021–Q4 2022, % change | −12 | 39 | 9 | 12 | 238 | −58 | −17 | −12 | |
| p Value | 0.028§ | 0.076 | 0.178 | .002§ | < 0.001§ | < 0.001§ | 0.469 | 0.958 | |
Patients can contribute to multiple categories.
Percentage of patients reporting substance use.
Percentage of total patient encounters
Significant at α = 0.05.
Figure 1.
(A) Total population (n = 19,187). (B) Population reporting fentanyl use (n = 1004).
Over the course of the study (Q3 2020 to Q4 2022), self-reported prescription opioid misuse increased 9% (p = 0.037), from 69 to 75 positive reports; cocaine use increased 82% (p = 0.034), from 125 to 228 positive reports; and fentanyl use increased 1760% (p < 0.001), from 10 to 186 positive reports. Conversely, heroin use decreased 16% (p < 0.001), from 171 to 143 positive reports during the same period. Self-reports of amphetamine, benzodiazepine, and methamphetamine use showed no significant trends throughout the study period (Table 2 and Figure 1A).
During Q2 2021, self-reported heroin use peaked, declining by 58% (p < 0.001), from 343 to 144 positive reports by Q4 2022. Conversely, positive self-reports increased by 12% for cocaine (204 vs. 228; p = 0.006), and 240% for fentanyl (55 vs. 187; p < 0.001) during this period (Table 2 and Figure 1A).
Following the sharp rise in self-reported fentanyl use after Q2 2021, we examined the co-occurrence of amphetamine, benzodiazepine, cocaine, heroin, methamphetamine, and prescription opioid use with fentanyl between Q2 2021 and Q4 2022. During this period, positive self-reports of co-occurring fentanyl and amphetamine, benzodiazepine, cocaine, heroin, and methamphetamine use increased by at least 100%, although heroin was the only significant change observed (p = 0.032) (Table 3 and Figure 1B).
Table 3.
Number of Self-Reports of Illicit Substance Use from Patients Reporting Fentanyl Use Presenting to Eight South Carolina Emergency Departments by annual quarter between april 1, 2021 – December 31, 2022
| Annual Quarter | Patients Reporting Fentanyl Use n (%)‡ | Substance Use, n* (%)† |
|||||
|---|---|---|---|---|---|---|---|
| Amphetamine | Benzodiazepine | Cocaine | Heroin | Methamphetamine | Prescription Opioids | ||
| Q2 2021 | 55 (6) | 0 | 3 (6) | 4 (7) | 25 (46) | 13 (24) | 8 (15) |
| Q3 2021 | 111 (15) | 2 (2) | 12 (11) | 7 (6) | 52 (47) | 42 (38) | 11 (10) |
| Q4 2021 | 108 (15) | 6 (6) | 17 (16) | 22 (20) | 41 (38) | 36 (33) | 15 (14) |
| Q1 2022 | 136 (18) | 4 (3) | 16 (12) | 18 (13) | 69 (51) | 39 (29) | 13 (10) |
| Q2 2022 | 161 (18) | 6 (4) | 17 (11) | 16 (10) | 55 (34) | 44 (27) | 20 (12) |
| Q3 2022 | 164 (20) | 5 (3) | 19 (12) | 24 (15) | 54 (33) | 51 (31) | 19 (12) |
| Q4 2022 | 186 (24) | 7 (4) | 18 (10) | 16 (9) | 55 (30) | 52 (28) | 15 (8) |
| Total | 921 (16) | 30 (3) | 102 (11) | 107 (12) | 351 (38) | 277 (30) | 101 (11) |
| Q2 2021–Q4 2022 % change | 238 | – | 500 | 300 | 124 | 300 | 88 |
| P value | < 0.001§ | 0.356‖ | .423‖ | 1.000‖ | .034§ | 0.606 | 0.189 |
Patients can contribute to multiple categories.
Percentage of patients reporting substance use.
Percentage of total patient encounters.
Significant at α = 0.05.
Fisher’s exact test.
Discussion
A 1760% increase in self-reported fentanyl use occurred during the time course of the study, accompanied by a 16% decline in heroin use. Fentanyl was initially developed as an anesthetic and analgesic for severe pain. Fentanyl’s unique pharmacological properties, including high activation of the μ-opioid receptor (100-fold more potent than morphine), rapid onset of action, high lipophilicity, and association with muscle rigidity have contributed to the rise of fentanyl use and deadly overdoses (12). Additionally, an increase in regular fentanyl use has complicated traditional buprenorphine induction approaches, including inductions in the ED, due to fears of, or actual precipitated, opioid withdrawal (13,14). The rise of fentanyl in the U.S. drug supply is multifactorial, including the fact that dose-for-dose, fentanyl is cheaper to produce than heroin and more easily distributed by e-commerce, mail, and couriers (15). Fentanyl can also replace heroin during periods of shortage, with reduced costs and risks to suppliers (16). As potent, inexpensive fentanyl is introduced to established heroin markets, some areas in the country have reported that fentanyl is either encompassing a significant portion or supplanting the illicit heroin marketplace altogether (17). Some opioid users develop tolerance to prescription opioids and heroin to the point that intoxication or “high” is no longer experienced, and fentanyl is seen and sold as being stronger and cheaper (7). Whereas some opioid users seek out illicit fentanyl intentionally, other substance users may not be aware that the illicit heroin, cocaine, methamphetamine, or benzodiazepine are, instead, fentanyl, or at least contaminated with fentanyl (17,18). National drug seizure data from the High Intensity Drug Trafficking Areas reported that fentanyl-containing individual pills increased from 42,202 to 2,089,189, and fentanyl powder seizures increased from 298.2 kg to 2416 kg, comparing the first quarter of 2018 to the last quarter of 2021 (19). The increased self-report of fentanyl use is consistent with the upsurge of fentanyl in the illicit drug market, which parallels the increase in opioid overdose deaths. In 2021, an estimated 106,699 drug overdose deaths occurred, a 16% increase from 2020, primarily driven by the increase of overdose deaths involving synthetic opioids other than methadone (20,21).
A 12% rise in cocaine use was found between Q2 2021 and Q4 2022. This is consistent with data from the Centers for Disease Control and Prevention, which reported that the rate of drug overdose deaths involving cocaine in 2021 was 21% higher than the rate in 2020 (20). According to the 2020 National Survey on Drug Use and Health, almost 5.2 million Americans aged 12 years or older used cocaine in the past year, with almost 500,000 people initiating cocaine for the first time (22). According to a United Nations World Drug Report (2021), the global manufacture of cocaine doubled between 2014 and 2019, reaching an estimated 17,840 tons, the highest level ever recorded (23). This increase in cocaine production has been attributed to the rise in domestic use (24). Key indicators such as cocaine seizure data, laboratory analysis of seized cocaine, price, and purity indicate that cocaine availability in the United States remains steady, with all Drug Enforcement Administration field divisions reporting moderate to high availability (17). Although not rising to the level of significance, likely related to sample size, the cooccurrence of nonprescribed fentanyl with cocaine and methamphetamine was not surprising. Between 2013 and 2018, LaRue et al. found a significant increase of 1850% (from 0.9% to 17.6%) in nonprescribed fentanyl positivity in cocaine-positive urine drug screens, and an increase of 798% (from 0.9%to 7.9%) among methamphetamine-positive samples across the United States (5). Polysubstance use is increasing and more dangerous than the use of only one substance, as evidenced by the increased mortality with illicit drug combinations. Polysubstance cocaine combinations, particularly those with fentanyl, have contributed to the increase in drug overdoses. Drug overdose deaths from cocaine and high potency synthetic opioids such as fentanyl increased in the United States from 167 in 2010 to 8659 in 2018, a 5085% increase coinciding with the onset of the fentanyl epidemic (17).
Limitations
One of the strengths of the study is that the results from the EDs represent geographically different areas of the state and types of hospital systems. However, as the sample is located entirely in South Carolina, the findings may not completely reflect national patterns. The number of people with risky substance use is likely underreported, as the initial screen was self-report and not all patients may have disclosed substance use, and some may have declined peer services. Although rarely prescribed, methamphetamine can be prescribed for attention deficit hyperactivity disorder and obesity, with the possibility of a rare false positive report. Lastly, these data come only from patients who were seen in the ED by a PRS, so those not seen by a PRS (e.g., those who came in during hours PRS were not present) are not represented.
Conclusions
Self-reported fentanyl use among patients presenting to ED settings increased 1760% over the course of the study period, whereas heroin decreased 16%. This shift likely reflects the changes in the illicit drug market and increasing availability of fentanyl. The study highlights the importance of screening ED patients for substance use and specifically enquiring about opioid and fentanyl use. Given the high rates of fentanyl ingestion, polysubstance use, and fentanyl contamination, distribution of take-home naloxone kits from EDs for patients identified with substance use (both opioid and non-opioid), as well as development of ED-induction paradigms for buprenorphine or methadone to decrease precipitated opioid withdrawal, are key overdose prevention strategies.
Article Summary.
1. Why is this topic important?
The United States is in the midst of a third wave of overdose deaths largely stemming from an increase in the use of illicitly manufactured fentanyl. Utilizing non-overdose-related patient-level data, rather than fatal overdose data, to monitor substance use trends can help combat the opioid crisis due to the time lag involved with collecting postmortem toxicology testing results and death certificate reports.
2. What does this study attempt to show?
How changes in self-reported illicit substance use, including fentanyl, other opioids, stimulants, and depressants, has changed over time in eight emergency departments across South Carolina.
3. What are the key findings?
Self-reported fentanyl use increased by 1760% and self-reported cocaine use increased by 82% between July 1, 2020 and December 31, 2022. Self-reported heroin use decreased by 16% over the same period.
4. How is patient care impacted?
Patient self-reported substance use data can inform prevention and harm reduction efforts during the ongoing opioid epidemic.
Acknowledgment
Funding for the project implemented in this paper was provided by the South Carolina Department of Health and Human Services.
Footnotes
Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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