Courtney A McKnight

Clinical Assistant Professor of Epidemiology

Professional overview

Dr. Courtney McKnight is a Principal Investigator specializing in mixed methods research focused on the epidemiology of drug use, opioid overdose, HIV and HCV infection.  Dr. McKnight has over 20 years of experience conducting public health research related to drug use, as well as field experience as a harm reduction service provider.

Prior to joining NYU, Dr. McKnight served as the assistant director of research at the Chemical Dependency Institute at the Icahn School of Medicine at Mount Sinai, where she was an investigator and project director on numerous federally funded research studies, including evaluations of syringe services programs; investigations of the drivers that contribute to disparate rates of HIV and HCV; and interventions to increase access to HIV and HCV testing and care.

Previous to Dr. McKnight’s work in research, she directed a harm reduction program for women who use drugs and volunteered at a syringe services program in New Jersey.

Dr. McKnight received her DrPH from the City University of New York Graduate Center, her Master of Public Health from Hunter College, and her Bachelor of Arts in sociology from Rutgers University. Her dissertation examined the impact of Medicaid coverage of methadone and buprenorphine on treatment access for opioid dependent beneficiaries.

Dr. McKnight’s current research interests include examining the shifting landscape of illicit opioids, including the increasing prevalence of illicitly manufactured fentanyl, and risk environments of people who use drugs.

Education

BA, Women's Studies, Rutgers University, New Brunswick, NJ

MPH, Community Health Education, Hunter College, New York, NY

DrPH, The City University of New York, New York, NY

Areas of research and study

Behavioral Science

Drug addiction

Epidemiology

Harm reduction

Hepatitis

HIV/AIDS

Infectious Diseases

Mixed-Methods Research

Opioid

Qualitative Research

Social epidemiology

Substance Abuse

Publications

Publications

Hepatitis C treatment outcomes among people who inject drugs experiencing unstable versus stable housing: Systematic review and meta-analysis

Kimball, S., Reynoso, M., McKnight, C., & Des Jarlais, D. (n.d.).

Publication year

2024

Journal title

PloS one

Volume

19

Issue

4

Page(s)

e0302471

10.1371/journal.pone.0302471

Abstract

Abstract

BACKGROUND: The prevalence of hepatitis C virus (HCV) among people who inject drugs (PWID) is between 50-70%. Prior systematic reviews demonstrated that PWID have similar direct acting antiviral treatment outcomes compared to non-PWID; however, reviews have not examined treatment outcomes by housing status. Given the links between housing and health, identifying gaps in HCV treatment can guide future interventions. METHODS: We conducted a systematic review using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched six databases for articles from 2014 onward. Two reviewers conducted title/abstract screenings, full-text review, and data extraction. We extracted effect measures for treatment initiation, adherence, completion, success, and reinfection by housing status. Studies underwent quality and certainty assessments, and we performed meta-analyses as appropriate. RESULTS: Our search yielded 473 studies, eight of which met inclusion criteria. Only the treatment initiation outcome had sufficient measures for meta-analysis. Using a random-effects model, we found those with unstable housing had 0.40 (0.26, 0.62) times the odds of initiating treatment compared to those with stable housing. Other outcomes were not amenable for meta-analysis due to a limited number of studies or differing outcome definitions. CONCLUSIONS: Among PWID, unstable housing appears to be a barrier to HCV treatment initiation; however, the existing data is limited for treatment initiation and the other outcomes we examined. There is a need for more informative studies to better understand HCV treatment among those with unstable housing. Specifically, future studies should better define housing status beyond a binary, static measure to capture the nuances and complexity of housing and its subsequent impact on HCV treatment. Additionally, researchers should meaningfully consider whether the outcome(s) of interest are being accurately measured for individuals experiencing unstable housing.

COVID-19 vaccination and HIV transmission among persons who inject drugs during the first two years of the COVID-19 pandemic in New York City

Field Testing the “Avoid the Needle” Intervention for Persons at Risk for Transitioning to Injecting Drug Use in Tallinn, Estonia and New York City, USA

Global epidemiology of abortion among female sex workers: a systematic review, meta-analysis, and meta-regression

Khezri, M., Tavakoli, F., Schwartz, S., Karamouzian, M., Sharifi, H., McKnight, C. A., Jarlais, D. D., Baral, S., & Shokoohi, M. (n.d.).

Publication year

2023

Journal title

Annals of Epidemiology

Volume

85

Page(s)

13-37

10.1016/j.annepidem.2023.06.022

Abstract

Abstract

Purpose: Despite the evidence of a high rate of unintended pregnancy, there remains limited information about the prevalence and experiences of abortion among female sex workers (FSWs). In response, we aimed to summarize the available evidence on abortion among FSWs. Methods: We searched Medline, Embase, PsycINFO, CINAHL, Scopus, and Web of Science from inception to January 29, 2023. We pooled data from the included studies using random-effects meta-analyses. We also grouped countries for the legality of elective abortion stratified by the United Nations database on abortion laws and policies. Results: We identified 60 eligible studies from 2031 potentially eligible records. The pooled lifetime prevalence of at least one and multiple induced abortions was 37.7% (95% confidence interval, 31.8–43.7) and 21.7% (14.9–29.2), respectively. Among FSWs recruited in countries where elective abortion is illegal, at least one induced abortion prevalence was 35.1% (28.1–42.4), and multiple induced abortion prevalence was 23.1% (12.4–35.9). In countries where elective abortion is legal, at least one induced abortion prevalence was 44.6% (34.8–54.6), and multiple induced abortion prevalence was 19.9% (11.9–29.3). Among FSWs experiencing abortion, self-managed abortion prevalence was estimated at 32.8% (23.6–42.7) overall, 42.8% (37.2–48.5) for countries where elective abortion is illegal, and 15.6% (3.9–32.7) for countries that legally allow elective abortion. Conclusions: Induced abortion is prevalent among FSWs, highlighting the need for interventions to increase access to effective contraception and safe abortion care. While induced abortion prevalence did not significantly differ across the legal grounds for abortion, self-managed abortion prevalence was higher in countries where elective abortion was illegal, highlighting the urgent need for accessible abortion services for FSWs in criminalized settings. Moving forward necessitates implementing and evaluating culturally acceptable models of safe abortion and post-abortion care for FSWs to increase access to the full spectrum of sexual and reproductive health services.

HIV risk and prevention among clients of a delivery-based harm reduction service during an HIV outbreak among people who use drugs in northern rural Minnesota, USA

Palayew, A., Knudtson, K., Purchase, S., Clark, S., Possehl, L., Healy, E., Deutsch, S., McKnight, C. A., Des Jarlais, D., & Glick, S. N. (n.d.).

Publication year

2023

Journal title

Harm Reduction Journal

Volume

20

Issue

1

10.1186/s12954-023-00839-1

Abstract

Abstract

Background: Since 2019, multiple HIV outbreaks occurred among people who inject drugs (PWID) in Minnesota. Syringe service programs (SSPs) are evidence-based programs that reduce the spread of HIV. We conducted an assessment of characteristics and HIV risk and prevention among clients of a delivery-based SSP near an HIV outbreak in rural, northern Minnesota. Methods: In the fall of 2021, we conducted a cross-sectional survey of clients of a mobile SSP based in Duluth, Minnesota. Survey topics included demographics, drug use, sexual behavior, HIV testing history, and HIV status. We conducted descriptive analyses and used univariate logistic regression to identify correlates of syringe sharing. The analysis was limited to PWID in the last six months. Results: A total of 125 people were surveyed; 77 (62%) were PWID in the last six months. Among these participants, 52% were female and 50% were homeless. Thirty-two percent reported sharing syringes and 45% reported sharing injecting equipment. Approximately one-half (49%) of participants had been tested for HIV in the past year, and none reported being HIV-positive. Individuals reported low condom usage (88% never used), and 23% of participants reported engaging in some form of transactional sex in the last six months. Incarceration in the last year was associated with sharing syringes (odds ratio = 1.4, 95% confidence interval 1.1–1.8). Conclusion: HIV risk was high among PWID receiving services at this SSP. These data highlight a rural SSP that is engaged with people at risk for HIV and needs additional support to expand harm reduction services.

Understanding intentionality of fentanyl use and drug overdose risk: Findings from a mixed methods study of people who inject drugs in New York City

McKnight, C., Weng, C. A., Reynoso, M., Kimball, S., Thompson, L. M., & Jarlais, D. D. (n.d.).

Publication year

2023

Journal title

International Journal of Drug Policy

Volume

118

10.1016/j.drugpo.2023.104063

Abstract

Abstract

Background: As the proportion of drug overdose deaths involving fentanyl continues to increase in the US, monitoring exposure to and possible changes in intention to use fentanyl among people who use drugs (PWUD) is of great public health importance. This mixed methods study examines intentionality of fentanyl use among persons who inject drugs (PWID) in New York City during a period of unprecedently high rates of drug overdose mortality. Methods: Between October 2021 and December 2022, N = 313 PWID were enrolled in a cross-sectional study that included a survey and urine toxicology screening. A subset of N = 162 PWID also participated in an in-depth interview (IDI) examining drug use patterns, including fentanyl use and experiences with drug overdose. Results: 83% of PWID were urine-toxicology positive for fentanyl, though only 18% reported recent intentional fentanyl use. Intentionality of fentanyl use was associated with being younger, white, increased drug use frequency, recent overdose (OD), recent stimulant use, among other characteristics. Qualitative findings suggest PWID tolerance to fentanyl may be increasing, which could result in an increased preference for fentanyl. Concern about overdose was common with nearly all PWID using overdose prevention strategies to avoid it. Conclusion: The findings from this study demonstrate a high prevalence of fentanyl use among PWID in NYC, despite an expressed preference for heroin. Our results suggest that the pervasiveness of fentanyl may be increasing fentanyl use and tolerance, which may contribute to an increased risk for drug overdose. Expanding access to existing evidence-based interventions such as naloxone and medications for opioid use disorder is necessary to reduce overdose mortality. Further, exploring the implementation of additional novel strategies to reduce the risk of drug overdose should be considered, including other forms of opioid maintenance treatment and expansion and government support for overdose prevention centers.

Modeling HIV transmission among persons who inject drugs (PWID) at the “End of the HIV Epidemic” and during the COVID-19 pandemic

Recurrent Injecting Drug Use as a Mediator between Psychiatric Disorder and Non-Fatal Overdose

Thick trust, thin trust, social capital, and health outcomes among trans women of color in New York City

Is your syringe services program cost-saving to society? A methodological case study

Hepatitis C incidence and prevalence among Puerto Rican people who use drugs in New York City

Toward the Interpretation of Positive Testing for Fentanyl and Its Analogs in Real Hair Samples: Preliminary Considerations

Salomone, A., Bigiarini, R., Palamar, J. J., McKnight, C., Vinsick, L., Amante, E., Di Corcia, D., & Vincenti, M. (n.d.).

Publication year

2020

Journal title

Journal of Analytical Toxicology

Volume

44

Issue

4

Page(s)

362-369

10.1093/jat/bkz102

Abstract

Abstract

The detection of new psychoactive substances (NPS) in hair has become extensively researched in recent years. Although most NPS fall into the classes of synthetic cannabinoids and designer cathinones, novel synthetic opioids (NSO) have appeared with increasing frequency in the illicit drug supply. While the detection of NSO in hair is now well documented, interpretation of results presents several controversial issues, as is quite common in hair analysis. In this study, an ultra-high-performance liquid chromatography-tandem mass spectrometry method able to detect 13 synthetic opioids (including fentanyl analogs) and metabolites in hair was applied to 293 real samples. Samples were collected in the USA between November 2016 and August 2018 from subjects who had reported heroin use in the past year or had already tested positive to hair testing for common opiates. The range, mean and median concentrations were calculated for each analyte, in order to draw a preliminary direction for a possible cut-off to discriminate between exposure to either low or high quantities of the drug. Over two-thirds (68%) of samples tested positive for fentanyl at concentrations between LOQ and 8600 pg/mg. The mean value was 382 pg/mg and the median was 95 pg/mg. The metabolites norfentanyl and 4-ANPP were also quantified and were found between LOQ and 320 pg/mg and between LOQ and 1400 pg/mg, respectively. The concentration ratios norfentanyl/fentanyl, 4-ANPP/fentanyl and norfentanyl/4-ANPP were also tested as potential markers of active use and to discriminate the intake of fentanyl from other analogs. The common occurrence of samples positive for multiple drugs may suggest that use is equally prevalent among consumers, which is not the case, as correlations based on quantitative results demonstrated. We believe this set of experimental observations provides a useful starting point for a wide discussion aimed to better understand positive hair testing for fentanyl and its analogs in hair samples.

Alternative kinship structures, resilience and social support among immigrant trans Latinas in the USA

Geographic distribution of risk ("Hotspots") for HIV, HCV, and drug overdose among persons who use drugs in New York City: The importance of local history

Injection and Heterosexual Risk Behaviors for HIV Infection Among Non-gay Identifying Men Who Have Sex with Men and Women

Prescription opiate analgesics, heroin, HIV and HCV among persons who inject drugs in New York City, 2016-2018

Being “hooked up” during a sharp increase in the availability of illicitly manufactured fentanyl: Adaptations of drug using practices among people who use drugs (PWUD) in New York City

Cost-effectiveness of hepatitis C screening and treatment linkage intervention in US methadone maintenance treatment programs

Hepatitis C virus prevalence and estimated incidence among new injectors during the opioid epidemic in New York City, 2000–2017: Protective effects of non-injecting drug use

Heterosexual male and female disparities in HIV infection at the end of an epidemic: HIV infection among persons who inject drugs in New York City, 2001–2005 and 2011–2015

Potential geographic "hotspots" for drug-injection related transmission of HIV and HCV and for initiation into injecting drug use in New York city, 2011-2015, with implications for the current opioid epidemic in the US

Decline in herpes simplex virus type 2 among non-injecting heroin and cocaine users in New York City, 2005 to 2014: Prospects for avoiding a resurgence of human immunodeficiency virus

Decline in HSV-2 among non-injecting Heroin and Cocaine users in New York City, 2005-2014: potential protection against HIV resurgence

Perceived discrimination among racial and ethnic minority drug users and the association with health care utilization

Racial/ethnic disparities at the end of an HIV epidemic: Persons who inject drugs in New York City, 2011-2015