We have read the journal's policy and the authors of this manuscript have the following competing interests: ESA, CR, KB, HL, AC, and DAEW received funding from Gilead Sciences FOCUS Grant. The grant provided partial salary support and program support for HIV and HCV screening in the emergency department. This does not alter our adherence to PLOS ONE policies on sharing data and materials.
The opioid epidemic has led to an increase in the number of persons who inject drugs, and this population accounts for 12% of new human immunodeficiency virus (HIV) and 60% of new hepatitis C virus (HCV) infections in the United States annually. While persons who inject drugs disproportionately utilize the emergency department (ED), accurate data is lacking on the prevalence and patterns of injection drug use, and prevalence of co-occurring HIV and HCV infections among ED patients.
The primary outcome was to assess the prevalence of injection drug use and co-occurring HIV and HCV infection among patients presenting to an urban ED.
This was a cross sectional study conducted at an urban ED, with an annual census of 65,000 visits. A closed-response questionnaire was developed based on publicly available validated surveys to assess patterns of injection drug use and HIV and HCV infection status, and administered by trained research assistants to all registered adult patients during 4-hour blocks of time.
Of the 2,319 eligible patients, 2,200 (94.9%) consented and completed the survey. 241 (11.0%) had ever used injection drugs, 103 (4.7%) currently used injection drugs, and 138 (6.3%) formerly used injection drugs. White patients age 25 to 34 years and white patients age 55 to 64 years had the highest prevalence of current (25.6%) and former (27.1%) injection drug use, respectively. Persons who use injection drugs had a higher prevalence of HCV infection (52.7% vs. 3.4%) and HIV infection (6.2% vs. 1.8%) than the rest of the population.
A high prevalence of ED patients report injection drug use, and this population self-reports a high prevalence of HIV and HCV infection. Emergency departments are in a unique position to engage with this population with regards to substance use treatment and linkage to care for HIV and HCV infection.
The opioid epidemic has led to an increase in the number of persons who inject drugs (PWID). Most notably, this increase in PWID has been related to the opioid epidemic and non-medical use of prescription opioids [
In addition to blood-borne viral infections, PWID have a complex set of health-related problems, including high rates of skin and soft tissue infections, overdose, and homelessness, and low rates of health insurance and access to primary care [
Unfortunately, accurate data is lacking on the number of PWID in the ED, and available studies use probability surveys to estimate utilization or a combination of international classification disease codes to estimate PWID prevalence in various care settings [
The main goals of this study were to estimate the PWID prevalence among patients presenting to an urban ED and to compare the HIV and HCV co-infection rates between those who report injection drug use and those who do not.
We performed a cross-sectional study of adult patients presenting to the Highland Hospital ED. This study was approved by the Highland Hospital, Alameda Health System (AHS), institutional review board. Patients provided written informed consent to participate.
Highland Hospital is an urban teaching hospital in Oakland, California with an accredited 4-year Emergency Medicine residency program. The annual ED volume is approximately 65,000 patients; 2% of patients are less than 12 years of age; approximately 40% of patients are black, 40% Hispanic, 15% white; and 45% are female. Roughly 75% of patients have public insurance, 15% are uninsured, and 10% of patients have private insurance. The Highland Hospital ED has a formal program for the initiation of buprenorphine for patients with opioid use disorder, as well as harm reduction initiatives for patients who use injection drugs, and provides routine HIV and HCV screening to adult patients. Approximately 25% of all adult ED patients have received annual HIV and HCV screening since 2014. Additionally, community clinics and syringe services programs have offered routine HIV and HCV screening for PWID, resulting in relatively high rates of knowledge about blood-borne viral infections in this patient population.
Adult patients ≥18 years were eligible for survey administration if they completed triage registration, spoke Spanish or English, were medically stable, and able to provide informed consent. Surveys were conducted in private areas in the waiting room, Fast Track, or the main ED.
The survey was developed by study staff with expertise in this field (DAEW and ESA). The survey elicited patient injection drug use history and self-report of HIV and HCV infection and treatment (
Five volunteer research assistants (RAs), who were blinded to the study purpose, administered the surveys from November 2018 through April 2019. The RAs worked in pairs during assigned 4-hour time blocks on pre-set weekdays from 10am to 2pm. At the beginning of each shift, RAs reviewed the ED tracking board to identify all adult patients who were registered, which represented the cohort of potentially eligible patients. Patients were deemed medically stable if they were awake and alert and able to participate in conversation with the RA. In an effort to prevent selection bias, RAs were blinded to any test results, the reason for the patient’s visit, and were not given access to the patient’s medical record. Further study eligibility was evaluated at the bedside and participating patients completed written consent prior to survey administration. Participants were not compensated for participation in the survey. Patients were able to decline a survey if they reported participating in the past.
The primary outcome was the proportion of surveyed patients who had ever used injection drugs. Secondary outcomes were the proportion of surveyed patients with HIV or HCV co-infection and ED utilization. Emergency department utilization was defined as the number of ED visits during the year prior to the index visit.
All patients who completed the survey were analyzed. Any duplicate patients were removed, and only the initial survey results were used as part of the analysis. Descriptive analyses were performed for all variables. Categorical data are reported as numbers and percentages and continuous data are reported as means with standard deviation (SD). When appropriate, absolute differences in proportion with 95% confidence intervals (CI) were calculated, and odds ratios were calculated to display relative differences between categories. Statistical analyses were performed using Microsoft Excel (Version 14.3.7, Microsoft Corporation) and Stata (Version 13, Stata Corporation, College Station, TX). Injection drug use was defined as any non-medically sanctioned drug taken by intravenous, intramuscular, or subcutaneous routes for non-medical use, and included opioids, amphetamine-type stimulants, and cocaine. Based on their self-reported injection drug use, surveyed patients were categorized as either
Between November 2018 and April 2019 there were a total of 24,309 patients who presented to the ED for care, of whom 4,334 (17.8%) were registered during study hours when RAs were enrolling patients. Of the patients who were registered during study hours, 2,319 (53.5%) were eligible for survey administration and 2,200 consented and completed the survey.
Characteristics of the unique ED census and surveyed patients, stratified by injection drug use history, can be found in
Unique Census | All Patients | Never PWID |
Ever PWID |
Absolute Difference % | Unadjusted Odds Ratio | |
---|---|---|---|---|---|---|
N = 24,309 | N = 2,200 (%) | N = 1,959 (%) | N = 241 (%) | (95% CI) | ||
44.6 (17.0) | 49.8 (16.4) | 49.5 (16.6) | 51.7 (14.5) | 2.2 (0.0 to 4.4) | -- | |
Age 18–24 | 2,931 (12.1) | 136 (6.2) | 133 (6.8) | 3 (1.2) | -5.6 (-7.4 to -3.8) | 0.2 (0.1 to 0.5) |
Age 25–34 | 5,572 (22.9) | 366 (16.6) | 326 (16.6) | 40 (16.6) | 0.0 (-5.0 to 5.0) | 1.0 (0.7 to 1.4) |
Age 35–44 | 4,788 (19.7) | 389 (17.7) | 345 (17.6) | 44 (18.3) | 0.7 (-5.9 to 4.5) | 1 (0.7 to 1.5) |
Age 45–54 | 4,133 (17.0) | 398 (18.1) | 365 (18.6) | 33 (13.7) | -4.9 (-9.6 to -0.2) | 0.7 (0.5 to 1.0) |
Age 55–64 | 3,753 (15.4) | 494 (22.5) | 422 (21.5) | 72 (29.9) | 8.4 (2.3 to 14.5) | 1.6 (1.2 to 2.1) |
Age 65–74 | 1,955 (8.0) | 276 (12.5) | 231 (11.8) | 45 (18.7) | 6.9 (1.8 to 12.0) | 1.7 (1.2 to 2.4) |
Age 75+ | 1,177 (4.8) | 133 (6.0) | 129 (6.6) | 4 (1.7) | -4.9 (-6.8 to -2.9) | 0.2 (0.1 to 0.6) |
Black | 8,876 (38.7) | 909 (41.3) | 793 (40.5) | 116 (48.1) | 7.6 (0.9 to 14.2) | 1.4 (1.0 to 1.8) |
Hispanic/Latino | 8,472 (40.0) | 678 (30.8) | 638 (32.6) | 40 (16.6) | -16.0 (-21.1 to -10.9) | 0.4 (0.3 to 0.6) |
White | 3,183 (13.9) | 311 (14.1) | 238 (12.1) | 73 (30.3) | 18.2 (12.2 to 24.2) | 3.1 (2.3 to 4.3) |
Asian | 2,150 (9.4) | 190 (8.6) | 184 (9.4) | 6 (2.5) | -6.9 (-9.3 to -4.5) | 0.2 (0.1 to 0.6) |
Other | 239 (1.04) | 23 (1.0) | 21 (1.1) | 2 (0.8) | -0.3 (-1.5 to 0.9) | 0.8 (0.2 to 3.3) |
Female | 11,162 (45.9) | 964 (43.8) | 900 (45.9) | 64 (26.6) | -19.3 (-25.3 to -13.3) | 0.4 (0.3 to 0.6) |
Male | 13,146 (54.1) | 1,236 (56.2) | 1,059 (54.1) | 177 (73.4) | 19.3 (13.3 to 25.3) | 2.4 (1.7 to 3.2) |
Medicaid | 14,880 (61.5) | 1,411 (64.1) | 1,255 (64.1) | 156 (64.7) | 0.6 (-5.8 to 7.0) | 1.0 (0.8 to 1.4) |
Medicare | 3,194 (13.2) | 439 (20.0) | 372 (19.0) | 67 (27.8) | 8.8 (2.9 to 14.7) | 1.6 (1.2 to 2.2) |
Uninsured | 3,587 (14.8) | 179 (8.1) | 173 (8.8) | 6 (2.5) | -6.3 (-8.6 to 4.0) | 0.5 (0.2 to 0.9) |
Private | 2,475 (10.2) | 161 (7.3) | 152 (7.8) | 9 (3.7) | -4.1 (-6.7 to -1.4) | 0.5 (0.2 to 0.9) |
763 (3.1) | 106 (4.8) | 67 (3.4) | 39 (16.2) | 12.8 (8.1 to 17.5) | 5.5 (3.6 to 8.3) | |
Admitted | 3,506 (14.4) | 655 (29.8) | 578 (29.5) | 77 (32.0) | 2.5 (-3.7 to 8.7) | 1.1 (0.8 to 1.5) |
Discharged | 20,803 (85.6) | 1,545 (70.2) | 1,381 (70.5) | 164 (68.0) | -2.5 (-8.7 to 3.7) | 0.9 (0.7 to 1.2) |
1 (1 to 1) | 1 (1 to 3) | 1 (1 to 2) | 2 (1 to 4) | P<0.014 | -- |
aSurveyed patients who report never injecting drugs.
bSurveyed patients who report ever injecting drugs, includes current and former injection drug use.
cEthnicity is non-Hispanic unless noted.
Absolute differences and odds ratios are calculated as a comparison between the Never PWID and Ever PWID cohorts. Comparison of median ED visits using Wilcoxon rank sum test.
Although hospital admission rates were similar between cohorts, ever PWID visited the ED more often in the preceding 12 months than never PWID (ever PWID: median 2 visits, IQR 1 to 4; never PWID: median 1 visit, IQR 1 to 2; p<0.001). There was no difference in the median number of ED visits or admission rates between former and current PWID.
(a) Prevalence of current injection drug use by age and race among 2,200 surveyed emergency department patients. (b) Prevalence of former injection drug use by age and race among 2,200 surveyed emergency department patients. Legend: Non-white includes Hispanic/Latino, Black, Asian, and other race and ethnicity categories. Current injection drug use indicates surveyed patients who report injecting drugs in the previous 12 months; former injection drug use indicates surveyed patients who report injecting drugs, but not in the past 12 months. Prevalence is based on the total number of patients surveyed in each age group, and ‘n’ indicates the number of patients that report current or former injection drug use.
The prevalence of self-reported HCV and HIV infection among surveyed patients can be found in
All | Never PWID |
Ever PWID |
Current PWID |
Former PWID |
|
---|---|---|---|---|---|
N = 2,200 (%) | N = 1,959 (%) | N = 241(%) | N = 103 (%) | N = 138 (%) | |
HIV Diagnosis | 51 (2.3) | 36 (1.8) | 15 (6.2) | 6 (5.8) | 9 (6.5) |
HCV Diagnosis | 194 (8.8) | 67 (3.4) | 127 (52.7) | 47 (45.6) | 80 (58.0) |
aSurveyed patients who report never injecting drugs.
bSurveyed patients who report ever injecting drugs, includes current and former injection drug use.
cSurveyed patients who report injecting drugs in the previous 12 months.
dSurveyed patients who report injecting drugs, but not in the past 12 months.
The reported continuums of care for HIV and HCV-infected patients can be found in
Never PWID |
Ever PWID |
Current PWID |
Former PWID |
|
---|---|---|---|---|
HIV Diagnosis | 36 | 15 | 6 | 9 |
In Care (%) | 22 (61.1) | 10 (66.7) | 3 (50) | 7 (77.8) |
On ART (%) | 19 (52.8) | 9 (60.0) | 2 (33.3) | 7 (77.8) |
HCV Diagnosis | 67 | 127 | 47 | 80 |
In Care (%) | 37 (55.2) | 54 (42.5) | 7 (14.9) | 47 (58.8) |
Cured (%) | 25 (37.3) | 40 (31.5) | 4 (3.9) | 36 (45.0) |
aSurveyed patients who report never injecting drugs.
bSurveyed patients who report ever injecting drugs, includes current and former injection drug use.
cSurveyed patients who report injecting drugs in the previous 12 months.
dSurveyed patients who report injecting drugs, but not in the past 12 months.
This study is limited by its single center design. Regional variation of the prevalence of PWID can be significant which limits the generalizability of our findings. Our ED treatment programs for opioid use disorder and harm reduction initiatives may actually skew our results by promoting increased ED utilization by PWID compared to other EDs that do not provide such services.
Additionally, the stigma associated with injection drug use, HIV, and HCV infection may compromise the validity of patient responses, possibly leading to underreporting of drug use, co-infection with HIV and HCV infection, and inaccurate assessments of current patterns of use and treatment adherence. Further, we dichotomized ever PWID into two groups, former and current PWID, in an attempt to identify the subgroup of active users who have with the greatest risk of transmitting and acquiring HIV and HCV infection and therefore are of the most public health concern [
We also note that due to the convenience sample methodology, it is unclear the impact of selection bias on our results. We report our study sample alongside the information about our total ED census, which helps to provide context to our results. Our findings rely on patient self-report, which, although accurately represents patient knowledge about their HIV and HCV infection status, may not reflect the true seroprevalence of disease in each cohort. Lastly, the low absolute numbers of PWID HIV and HCV-infected patients included in this study prevents making a detailed comparative analysis.
In this survey study of 2,200 patients in a Northern California urban ED, we found a significant proportion were ever PWID (11%), of which 45% were current PWID. Additionally, we report a significantly higher prevalence of HIV and HCV co-infection among ever PWID (HIV 6.2%; HCV 53%) than never PWID (HIV 1.8%; HCV 3.4%). Lastly, ED patients with HIV or HCV infection who were also current PWID were less likely to receive care for their infections than former and never PWID.
Injection drug use is a significant driver of HCV and HIV transmission through high-risk practices of sharing needles, syringes, and other drug injection equipment, as well as from associated risk environments [
Our results are in line with estimates of PWID prevalence among urban ED populations in other parts of the US. An HCV seroprevalence study in the Johns Hopkins ED in Baltimore, Maryland, found that 7% of the patients in their cohort were ever PWID based on chart review [
We also found a high prevalence of both HIV infection (6.2%) and HCV infection (53%) among PWID in our urban ED, both several-fold higher than patients who reported never using injection drugs. Moreover, the true prevalence of these infections in our PWID cohort is likely even higher than these estimates based on self-report. We previously found that many of the current PWID in our ED had not undergone recent HIV or HCV screening. Our findings underscore the importance of protocolized HIV and HCV screening for all ED patients who are identified as PWID.
The ED is at the nexus of care for PWID and those with HIV and HCV infections [
Despite these interventions, engagement and linkage to care for ED PWID remains challenging.
We found large drop-offs in the linkage to care and treatment rates for surveyed ED patients with HIV and HCV infection, with the lowest rates among PWID. National estimates report that nearly 80% of PWID living with HIV are linked to care, but only 50% are retained in care [
While comprehensively addressing the intertwined public health issues of injection drug use and HIV and HCV infection has improved care and treatment for some patients, the majority have complex needs and face significant barriers to care. Given the significant impact of these illnesses, and the central role that the ED plays in the care of these patients, further ED research aimed at this high-risk cohort is needed, evaluating best practices, as well as new and creative initiatives.
A high prevalence of ED patients are PWID, and this population self-reports a high prevalence of HIV and HCV infection. Emergency departments are in a unique position to engage with this population with regards to substance use treatment as well as screening and engagement to care for HIV and HCV infection.
(PDF)
The authors would like to acknowledge Bradley Frazee, MD his support in this project.
PONE-D-20-02701
High Prevalence Of Injection Drug Use And Blood-Borne Viral Infections Among Patients In An Urban Emergency Department
PLOS ONE
Dear Dr. Anderson,
Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.
The authors should address all of the critiques raised by the review, and which I concur with. I also urge the authors to be more transparent in the abstract regarding prevalence of
We would appreciate receiving your revised manuscript by April 25, 2020. When you are ready to submit your revision, log on to
If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter.
To enhance the reproducibility of your results, we recommend that if applicable you deposit your laboratory protocols in protocols.io, where a protocol can be assigned its own identifier (DOI) such that it can be cited independently in the future. For instructions see:
Please include the following items when submitting your revised manuscript:
A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). This letter should be uploaded as separate file and labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. This file should be uploaded as separate file and labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. This file should be uploaded as separate file and labeled 'Manuscript'.
Please note while forming your response, if your article is accepted, you may have the opportunity to make the peer review history publicly available. The record will include editor decision letters (with reviews) and your responses to reviewer comments. If eligible, we will contact you to opt in or out.
We look forward to receiving your revised manuscript.
Kind regards,
Kimberly Page, PhD, MPH
Academic Editor
PLOS ONE
Additional Editor Comments (if provided):
I concur I concur with the review regarding the weaknesses of the study: including the lack of information about people who did not take the survey, the survey instrument validity, the weaknesses of self-reported infection status and editing the figures. However, I think that the authors can address these critiques with a major revision, noting the more carefully the strengths and weaknesses of the study. For example what are HIV and HCV testing rates in this area? If they are high, do they inspire confidence in the self-reported prevalence. Addressing the potential biases of the study are important and not over-interpreting the results.
Journal Requirements:
When submitting your revision, we need you to address these additional requirements:
1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at
2. Please ensure that you refer to Figure 1 in your text as, if accepted, production will need this reference to link the reader to the figure.
3. We note that you have indicated that data from this study are available upon request. PLOS only allows data to be available upon request if there are legal or ethical restrictions on sharing data publicly. For information on unacceptable data access restrictions, please see
In your revised cover letter, please address the following prompts:
a) If there are ethical or legal restrictions on sharing a de-identified data set, please explain them in detail (e.g., data contain potentially identifying or sensitive patient information) and who has imposed them (e.g., an ethics committee). Please also provide contact information for a data access committee, ethics committee, or other institutional body to which data requests may be sent.
b) If there are no restrictions, please upload the minimal anonymized data set necessary to replicate your study findings as either Supporting Information files or to a stable, public repository and provide us with the relevant URLs, DOIs, or accession numbers. Please see
We will update your Data Availability statement on your behalf to reflect the information you provide.
4. Thank you for stating the following in the Competing Interests section:
"I have read the journal's policy and the authors of this manuscript have the following competing interests:
ESA, CR, KB, HL, AC, and DAEW received funding from Gilead Sciences FOCUS Grant. The grant provided partial salary support and program support for HIV and HCV screening in the emergency department. "
Please confirm that this does not alter your adherence to all PLOS ONE policies on sharing data and materials, by including the following statement: "This does not alter our adherence to PLOS ONE policies on sharing data and materials.” (as detailed online in our guide for authors
Please include your updated Competing Interests statement in your cover letter; we will change the online submission form on your behalf.
Please know it is PLOS ONE policy for corresponding authors to declare, on behalf of all authors, all potential competing interests for the purposes of transparency. PLOS defines a competing interest as anything that interferes with, or could reasonably be perceived as interfering with, the full and objective presentation, peer review, editorial decision-making, or publication of research or non-research articles submitted to one of the journals. Competing interests can be financial or non-financial, professional, or personal. Competing interests can arise in relationship to an organization or another person. Please follow this link to our website for more details on competing interests:
[Note: HTML markup is below. Please do not edit.]
Reviewers' comments:
Reviewer's Responses to Questions
1. Is the manuscript technically sound, and do the data support the conclusions?
The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.
Reviewer #1: Partly
**********
2. Has the statistical analysis been performed appropriately and rigorously?
Reviewer #1: No
**********
3. Have the authors made all data underlying the findings in their manuscript fully available?
The
Reviewer #1: No
**********
4. Is the manuscript presented in an intelligible fashion and written in standard English?
PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.
Reviewer #1: Yes
**********
5. Review Comments to the Author
Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)
Reviewer #1: The manuscript details results from a convenience sample survey of approximately 2,200 emergency department (ED) patients at a single urban ED (Highland) in Oakland, CA. The survey focuses on assessing injection drug use (IDU) history and self-reported HIV and hepatitis C (HCV) infections. The authors report high rates of IDU (and HIV and HCV) among their sample. The findings are relatively limited, including only a few demographic and visit characteristics. Within their findings, the note high reported IDU (e.g., 26% in respondents 25-34 years) and generally high rates of HIV (6%) and HCV (53%) infection.
The authors report a very high response rate--about 95%. The challenge is interpreting this number is that the authors do not describe the characteristics of 2,015 patients that they did not approach--and critically why not? Where these patients too ill? Intoxicated? Spoke a language other than English or Spanish? Discharged before the RA could approach them for participation? This information is critical to judge the validity of the remaining responses. The convenience sample design is practical, but it may have important implications on the findings. For example, if patients who inject drugs (or have HIV or HCV infection) have longer ED visits lengths of stay compared to their null counterparts, then the findings are subject to length biased sampling--and the results may be biased.
The convenience sample design, single site selection, and lack of methodologic details limit the general applicability of their findings.
Specific comments:
1. Abstract: The authors state that they used a 'validated questionnaire' in the abstract. This is a bit of an overstatement. The authors used 2 validated question items from the NIDA Clinical Trials Network (CTN) Common Data Elements (CDE). This is a strength in their methods, but a general overstatement to imply that the questionnaire was validated (it would be fair to say that 2 items were validated). The authors do not provide their questionnaire for review. They do not describe the other survey data elements.
2. The authors should clarify their use of 'Hispanic,' 'white,' and 'black'. In many contexts, Hispanic refers to ethnicity and white and black refer to race. I would presume that 'white' means 'non-Hispanic white' and 'black' means 'non-Hispanic black'. Again, if the questionnaire were provided as supplemental material, it would help gauge how the questions were asked.
3. Were subjects compensated in any way? Were there any duplicate respondents (more than 1 ED visit during the study period)? If so, how were they managed?
4. The statistical analysis is relatively simple, reporting percentages and absolute percentage differences between categories. The manuscript would be strengthened by a more robust analysis that included both absolute and relative differences (whether reporting as prevalence ratios or odds ratios). There are limited attempts to detect confounding or interaction (via limited stratification provided by text and not shown in tables). Sample size restrictions (of reported IDU, HIV, and HCV) limit the ability to adjust for confounding.
5. The figure is difficult to read. Colored bar graphs have poor data to ink ratios. Try point and line figures with meaning groupings. Two figures, one for current IDU and one for former IDU would be better--and would have a better data to ink ratio. IDU is also better than PWID, as the figures describe an action (IDU) rather than a general group characteristic (PWID).
6. The authors rely upon self-reported HIV and HCV infection. The authors do not describe how this information was collected (e.g., were respondents asked about HIV and HCV infections directly or was a staged approach used--have you ever had a test for HIV? When was the last time you were tested for HIV? Has a health care provider ever told you that your test was positive?). There are a number of validated screening tools to ask this information. Were they used? Furthermore, the authors allude to results (presumably from the same project) indicating that "many of the current PWID had not undergone recent HIV or HCV screening." This further calls into question the accuracy of their results (while estimates of self-reported HIV and HCV infection are important, the actual seroprevalence rates are really what we want to know). The authors should also report HIV/HCV co-infection rates.
7. The limitations included are appropriate, notably that these results come from a single urban center that serves a marginalized community. The authors should address the additional limitations noted above (e.g., reliance on self-reported HIV and HCV infection, unclear impact of selection biases).
8. In the discussion, the authors state that "we believe the prevalence of PWID among urban ED patients is between 7% and 11%". The authors should temper their conclusion. Estimates vary based upon methods and study samples. Certainly the prevalence of injection drug use is significant and deserves attention, but accurate unbiased estimates of IDU among ED patients remain unknown.
9. On page 10, "We performed a cross-sectional survey study..." Suggest rewording to either "We performed a cross-sectional study..." or "We surveyed..." The terms cross-sectional and survey essentially mean the same thing.
10. On page 11, please define how you operationalized 'medically stable'. Non-medically (presumably) trained research assistants collected the data. How did they determine 'medical stability'?
**********
6. PLOS authors have the option to publish the peer review history of their article (
If you choose “no”, your identity will remain anonymous but your review may still be made public.
Reviewer #1: No
[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files to be viewed.]
While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool,
Dear PLOS ONE Editorial board,
Thank you for your continued consideration of manuscript PONE-D-20-02701 "High Prevalence of Injection Drug Use and Blood-Borne Viral Infections In An Urban Emergency Department”. A revised version of the manuscript has been submitted along with this cover letter.
We appreciate the reviewers’ excellent feedback and comments. Below we have included each reviewer comment, followed by our replies:
Below we also address additional Editor and Reviewer comments. Our responses are in Bold and Italics.
Additional Editor Comments (if provided):
I concur with the review regarding the weaknesses of the study: including the lack of information about people who did not take the survey, the survey instrument validity, the weaknesses of self-reported infection status and editing the figures. However, I think that the authors can address these critiques with a major revision, noting the more carefully the strengths and weaknesses of the study. For example, what are HIV and HCV testing rates in this area? If they are high, do they inspire confidence in the self-reported prevalence. Addressing the potential biases of the study are important and not over-interpreting the results.
We appreciate the constructive comments from the editorial team. We have added detailed information about the patients who did not complete the survey to the manuscript, addressed the limitations to the validity to the survey instrument, and discussed the weaknesses related to patient self-report of HIV/HCV status, as well as modifications to our figure. These are specifically addressed below when noted by the reviewer, and all changes to the manuscript are tracked in the re-submitted document.
We have also added an additional figure for study enrollment and eligibility to delineate reasons patients were not able to participate, and have added an entire column to Table 1 with information about the entire ED census so that it can be compared to the study sample. We believe these editions will allow readers to interpret our findings with more context on potential methodologic biases.
Specifically, with regards to this comment from the editor, in the Methods section of the manuscript, we have added information about both ED and community HIV/HCV. We have addressed the potential biases in this manuscript, with specific responses related to reviewer comments as noted below.
Reviewers' comments:
Review Comments to the Author
Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)
Reviewer #1: The manuscript details results from a convenience sample survey of approximately 2,200 emergency department (ED) patients at a single urban ED (Highland) in Oakland, CA. The survey focuses on assessing injection drug use (IDU) history and self-reported HIV and hepatitis C (HCV) infections. The authors report high rates of IDU (and HIV and HCV) among their sample. The findings are relatively limited, including only a few demographic and visit characteristics. Within their findings, the note high reported IDU (e.g., 26% in respondents 25-34 years) and generally high rates of HIV (6%) and HCV (53%) infection.
The authors report a very high response rate--about 95%. The challenge is interpreting this number is that the authors do not describe the characteristics of 2,015 patients that they did not approach--and critically why not? Where these patients too ill? Intoxicated? Spoke a language other than English or Spanish? Discharged before the RA could approach them for participation? This information is critical to judge the validity of the remaining responses. The convenience sample design is practical, but it may have important implications on the findings. For example, if patients who inject drugs (or have HIV or HCV infection) have longer ED visits lengths of stay compared to their null counterparts, then the findings are subject to length biased sampling--and the results may be biased.
Thank you for this feedback. We have added to Table 1 the characteristics of the entire ED census during the study period. With this information presented side-by-side with the patients who completed the survey, we believe readers will have an objective assessment of any bias with survey administration.
We have also added a new Figure 1, which shows the flow of patients who were eligible for survey administration, and the reasons patients were not approached for survey administration – of note, many patients had several reasons why they were not approached.
The convenience sample design, single site selection, and lack of methodologic details limit the general applicability of their findings.
Yes, we agree these are limitations to our manuscript, and have expanded our limitations section to highlight these issues. We have also strengthened the methodologic details in order to address some of the important concerns mentioned by the reviewer.
Specific comments:
1. Abstract: The authors state that they used a 'validated questionnaire' in the abstract. This is a bit of an overstatement. The authors used 2 validated question items from the NIDA Clinical Trials Network (CTN) Common Data Elements (CDE). This is a strength in their methods, but a general overstatement to imply that the questionnaire was validated (it would be fair to say that 2 items were validated). The authors do not provide their questionnaire for review. They do not describe the other survey data elements.
We have clarified the language in the abstract to say that our survey was based on validated surveys, rather than suggest that the entire questionnaire was validated. We have also provided the survey as an appendix.
2. The authors should clarify their use of 'Hispanic,' 'white,' and 'black'. In many contexts, Hispanic refers to ethnicity and white and black refer to race. I would presume that 'white' means 'non-Hispanic white' and 'black' means 'non-Hispanic black'. Again, if the questionnaire were provided as supplemental material, it would help gauge how the questions were asked.
We have clarified the race and ethnicity in Table 1; white refers to non-Hispanic white and black refers to non-Hispanic black. The survey is provided as an appendix.
3. Were subjects compensated in any way? Were there any duplicate respondents (more than 1 ED visit during the study period)? If so, how were they managed?
We did not compensate patients for participation. Patients were not permitted to take the survey more than once, and during data analysis, duplicate patients were removed and only the initial survey was used in the data analysis. This information was added to the methods section of the revised manuscript.
4. The statistical analysis is relatively simple, reporting percentages and absolute percentage differences between categories. The manuscript would be strengthened by a more robust analysis that included both absolute and relative differences (whether reporting as prevalence ratios or odds ratios). There are limited attempts to detect confounding or interaction (via limited stratification provided by text and not shown in tables). Sample size restrictions (of reported IDU, HIV, and HCV) limit the ability to adjust for confounding.
Thank you for this feedback. While our initial inclination was to display raw data with fewer statistical tests, we understand and agree with the rational for reporting a higher level of analysis. We have added absolute comparison between groups into Table 1, calculated as a difference in proportions with a 95% confidence interval. We have calculated unadjusted odds ratios to demonstrate relative differences between groups. With these additional analysis, we feel that our findings are more robust and convey more meaningful information for readers.
We have also added to the results section summary comparison statistics, though refer to Table 1 to not repeat information in text form that is available in table form.
5. The figure is difficult to read. Colored bar graphs have poor data to ink ratios. Try point and line figures with meaning groupings. Two figures, one for current IDU and one for former IDU would be better--and would have a better data to ink ratio. IDU is also better than PWID, as the figures describe an action (IDU) rather than a general group characteristic (PWID).
We appreciate the feedback on the figure. We have modified the figure (now Figure 2) into two figures (Figure 2a and Figure 2b), with one for current and the other for former injection drug use. We feel that the breakdown in each figure of non-Hispanic white and non-white by age group conveys meaningful information consistent with the public health dialogue surrounding injection drug use. The figure is also gray-scale for readability.
6. The authors rely upon self-reported HIV and HCV infection. The authors do not describe how this information was collected (e.g., were respondents asked about HIV and HCV infections directly or was a staged approach used--have you ever had a test for HIV? When was the last time you were tested for HIV? Has a health care provider ever told you that your test was positive?). There are a number of validated screening tools to ask this information. Were they used? Furthermore, the authors allude to results (presumably from the same project) indicating that "many of the current PWID had not undergone recent HIV or HCV screening." This further calls into question the accuracy of their results (while estimates of self-reported HIV and HCV infection are important, the actual seroprevalence rates are really what we want to know). The authors should also report HIV/HCV co-infection rates.
We have added the survey as an appendix to clarify which questions were used for each datapoint. We also have added to the manuscript information about background rates of HIV and HCV testing in this population. While we do note that many patients had not had recent screening in our ED, there is widespread testing available for this community in our area – as well as our ED – and we have discussed this further in the manuscript in the background section.
7. The limitations included are appropriate, notably that these results come from a single urban center that serves a marginalized community. The authors should address the additional limitations noted above (e.g., reliance on self-reported HIV and HCV infection, unclear impact of selection biases).
We have added an expanded discussion of the limitations of our findings, including those noted by both the reviewer and the editor.
8. In the discussion, the authors state that "we believe the prevalence of PWID among urban ED patients is between 7% and 11%". The authors should temper their conclusion. Estimates vary based upon methods and study samples. Certainly the prevalence of injection drug use is significant and deserves attention, but accurate unbiased estimates of IDU among ED patients remain unknown.
Our language has been modified to temper our conclusions.
9. On page 10, "We performed a cross-sectional survey study..." Suggest rewording to either "We performed a cross-sectional study..." or "We surveyed..." The terms cross-sectional and survey essentially mean the same thing.
We have changed this sentence to “We performed a cross-sectional study…”.
10. On page 11, please define how you operationalized 'medically stable'. Non-medically (presumably) trained research assistants collected the data. How did they determine 'medical stability'?
We have added to the methods how medical stability was assessed.
We appreciate your continued consideration of this manuscript and hope that it meets the high publication standards of PLOS ONE.
Sincerely,
Erik S. Anderson, MD
Corresponding Author
Submitted filename:
High Prevalence Of Injection Drug Use And Blood-Borne Viral Infections Among Patients In An Urban Emergency Department
PONE-D-20-02701R1
Dear Dr. Anderson,
We are pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it complies with all outstanding technical requirements.
Within one week, you will receive an e-mail containing information on the amendments required prior to publication. When all required modifications have been addressed, you will receive a formal acceptance letter and your manuscript will proceed to our production department and be scheduled for publication.
Shortly after the formal acceptance letter is sent, an invoice for payment will follow. To ensure an efficient production and billing process, please log into Editorial Manager at
If your institution or institutions have a press office, please notify them about your upcoming paper to enable them to help maximize its impact. If they will be preparing press materials for this manuscript, you must inform our press team as soon as possible and no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact
With kind regards,
Kimberly Page, PhD, MPH
Academic Editor
PLOS ONE
Additional Editor Comments (optional):
Reviewers' comments:
PONE-D-20-02701R1
High Prevalence Of Injection Drug Use And Blood-Borne Viral Infections Among Patients In An Urban Emergency Department
Dear Dr. Anderson:
I am pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department.
If your institution or institutions have a press office, please notify them about your upcoming paper at this point, to enable them to help maximize its impact. If they will be preparing press materials for this manuscript, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact
For any other questions or concerns, please email
Thank you for submitting your work to PLOS ONE.
With kind regards,
PLOS ONE Editorial Office Staff
on behalf of
Dr. Kimberly Page
Academic Editor
PLOS ONE