Using Network and Spatial Data to Better Target Overdose Prevention Strategies in Rural Appalachia

This analysis uses network and spatial data to identify optimal individuals to target with overdose prevention interventions in rural Appalachia. Five hundred and three rural persons who use drugs were recruited to participate in the Social Networks among Appalachian People Study (2008-2010). Interviewer-administered surveys collected information on demographic characteristics, risk behaviors (including overdose history), network members, and residential addresses. We restricted the sample to individuals with at least one confirmed relationship to another study participant (N = 463). Using dyadic analyses (N = 1428 relationships), we identified relationship-level correlates of relationships with network members who have previously overdosed. We then examined individual- and network-level factors associated with (1) having at least one first-degree alter (i.e., network member) with a prior overdose and (2) each additional network member with a prior overdose (N = 463 study participants). Overall, 28% of the sample had previously overdosed and 57% were one-degree away from someone who previously overdosed. Relationships with those who had overdosed were characterized by closer residential proximity. Those with at least one network member who previously overdosed were more geographically central and occupied more central network positions. Further, the number of network members with an overdose history increased with decreasing distance to the town center, increasing network centrality, and prior enrollment in an alcohol detox program. Because fatal overdoses can be prevented through bystander intervention, these findings suggest that strategies that target more central individuals (both geographically and based on their network positions) and those who have previously enrolled in alcohol detox programs with overdose prevention training and naloxone may optimize intervention reach and have the potential to curb overdose fatalities in this region.

Incarceration history and risk of HIV and hepatitis C virus acquisition among people who inject drugs: a systematic review and meta-analysis

BACKGROUND

People who inject drugs (PWID) experience a high prevalence of incarceration and might be at high risk of HIV and hepatitis C virus (HCV) infection during or after incarceration. We aimed to assess whether incarceration history elevates HIV or HCV acquisition risk among PWID.

METHODS

In this systematic review and meta-analysis, we searched MEDLINE, Embase, and PsycINFO databases for studies in any language published from Jan 1, 2000 until June 13, 2017 assessing HIV or HCV incidence among PWID. We included studies that measured HIV or HCV incidence among community-recruited PWID. We included only studies reporting original results and excluded studies that evaluated incident infections by self-report. We contacted authors of cohort studies that met the inclusion or exclusion criteria, but that did not report on the outcomes of interest, to request data. We extracted and pooled data from the included studies using random-effects meta-analyses to quantify the associations between recent (past 3, 6, or 12 months or since last follow-up) or past incarceration and HIV or HCV acquisition (primary infection or reinfection) risk among PWID. We assessed the risk of bias of included studies using the Newcastle-Ottawa Scale. Between-study heterogeneity was evaluated using the I2 statistic and the P-value for heterogeneity.

FINDINGS

We included published results from 20 studies and unpublished results from 21 studies. These studies originated from Australasia, western and eastern Europe, North and Latin America, and east and southeast Asia. Recent incarceration was associated with an 81% (relative risk [RR] 1·81, 95% CI 1·40-2·34) increase in HIV acquisition risk, with moderate heterogeneity between studies (I2=63·5%; p=0·001), and a 62% (RR 1·62, 95% CI 1·28-2·05) increase in HCV acquisition risk, also with moderate heterogeneity between studies (I2=57·3%; p=0·002). Past incarceration was associated with a 25% increase in HIV (RR 1·25, 95% CI 0·94-1·65) and a 21% increase in HCV (1·21, 1·02-1·43) acquisition risk.

INTERPRETATION

Incarceration is associated with substantial short-term increases in HIV and HCV acquisition risk among PWID and could be a significant driver of HCV and HIV transmission among PWID. These findings support the need for developing novel interventions to minimise the risk of HCV and HIV acquisition, including addressing structural risks associated with drug laws and excessive incarceration of PWID.

FUNDING

Engineering and Physical Sciences Research Council, National Institute for Health Research, National Institutes of Health.

Silence Surrounding Hepatitis C Status in Risk Relationships Among Rural People Who Use Drugs

Hepatitis C virus (HCV) has reached epidemic proportions in rural Central Appalachia in recent years. We sought to identify demographic, behavioral, and interpersonal characteristics associated with HCV serostatus disclosure among high risk people who use drugs (PWUD) in Appalachian Kentucky. HCV antibody-positive participants (n = 243), drawn from the fifth follow-up assessment of a longitudinal study of rural PWUD, completed interviewer-administered questionnaires eliciting demographic and interpersonal characteristics, risk behaviors, and information about HCV disclosure. We assessed correlates of HCV disclosure using gender-stratified multivariate logistic regression. Participants reported having disclosed their HCV-positive status to a current sex partner (44.0%), family member (35.8%), close friend (9.5%), or past sex partner (6.6%). Of those reporting current (n = 72) or past (n = 215) injection drug use (IDU), only 2.8% disclosed to current and 0.9% disclosed to past IDU partners, respectively. Female participants were more likely than male participants to disclose to current sex partners and family member(s). In multivariate analyses, adjusting for time since testing HCV positive, older age and lifetime history of drug treatment were associated with decreased odds of HCV disclosure among females, while only lifetime history of drug treatment was associated with decreased odds of HCV disclosure among males. In summary, the almost complete absence of disclosure to current or former injection drug use partners was concerning. However, most participants (69.1%) reported disclosing their HCV status to at least one of their social referents, suggesting that family members, partners, and friends of people living with HCV could play a critical role in encouraging uptake of treatment. Although further research is warranted, it is clear that interventions are needed to encourage HCV disclosure among those most at risk of transmitting HCV.

Risk of Heroin Dependence in Newly Incident Heroin Users

This study assesses data from the 2002 to 2016 US National Survey on Drug Use and Health data sets to determine the percentage of newly incident heroin users who became heroin dependent.

Implementing Treatment of Opioid-Use Disorder in Rural Settings: a Focus on HIV and Hepatitis C Prevention and Treatment

PURPOSE OF REVIEW

To describe the epidemiology of opioid-use disorder in the rural United States (U.S.) as it pertains to HIV and hepatitis C transmission and treatment resources.

RECENT FINDINGS

Heroin and fentanyl analogs have surpassed prescription opioids in their availability in rural opioid markets adding to HIV and hepatitis C (HCV) and overdose risks. Only 18% of rural individuals live in towns with inpatient services which are of limited quality and utility. Opioid treatment programs that provide methadone are not located in rural areas and only 3% of the primary care providers have the ability to prescribe buprenorphine. National models and resources have been established but lack implementation in rural areas leading to ongoing HIV and HCV transmission and overdose. Addressing the adverse impact of opioids in the rural U.S. will require a concerted effort to implement effective treatments according to national standards.

Drug Use and Incarceration among Rural Appalachian Women: Findings From a Jail Sample

BACKGROUND/OBJECTIVE

The purpose of this paper is to examine drug use and incarceration history among rural Appalachian women.

METHODS

This study involved random selection, screening, and interviews with rural women from local jails in Appalachia.

RESULTS

Of the women randomly selected and screened, 97% met criteria for substance use intervention. Significant factors associated with incarceration history included age, education, custody status, and mental health. A significant interaction was observed between male sex partners and drug use on incarceration history.

CONCLUSIONS

Study findings suggest that the drug/crime relationship among rural Appalachian women is associated with their high-risk home environment, partner relationships, and mental health. Specifically, in addition to drug use, factors such as family and child relationships, anxiety, victimization, and relationships with partners should also be considered in the trajectory of criminal careers among rural Appalachian women.

A qualitative analysis of gabapentin misuse and diversion among people who use drugs in Appalachian Kentucky

Gabapentin, an anticonvulsant and analgesic for postherpetic neuralgia, has been thought to have no abuse potential despite numerous published reports to the contrary. Gabapentin has been linked with impaired driving and opioid use, highlighting the need to more fully understand its risk profile. Thirty-three individuals reporting recent nonmedical use of gabapentin were recruited from two ongoing longitudinal studies of drug users in Appalachian Kentucky to participate in focus groups. Four sessions were held (two in the community and two in jail settings), during which participants responded to questions regarding their personal experiences with gabapentin misuse. Focus group participants were similar to other gabapentin users in the larger cohort studies with respect to demographics and drug use behaviors. Overall, the sample reported having initiated gabapentin more than 10 years earlier after having it prescribed for a legitimate, though generally off-label, medical indication (e.g., pain, anxiety, opioid detoxification). Participants reported use of gabapentin in combination with buprenorphine, other opioids, cocaine, and caffeine to produce sought-after central nervous system effects (e.g., muscle relaxation, pain reduction, sleep induction, feeling drunk, and feeling "high"). Focus group responses highlighted the low cost of gabapentin for the purpose of getting high and noted increasing popularity in the community, particularly over the last 2 years. Gabapentin was a prominent drug of abuse in two cohorts of the primarily opioid-using individuals. Providers should be aware of gabapentin's abuse potential, and a reexamination of the need for scheduling is warranted. (PsycINFO Database Record

A rural/urban comparison of privacy and confidentiality concerns associated with providing sensitive location information in epidemiologic research involving persons who use drugs

BACKGROUND

Analyses that link contextual factors with individual-level data can improve our understanding of the "risk environment"; however, the accuracy of information provided by participants about locations where illegal/stigmatized behaviors occur may be influenced by privacy/confidentiality concerns that may vary by setting and/or data collection approach.

METHODS

We recruited thirty-five persons who use drugs from a rural Appalachian town and a Mid-Atlantic city to participate in in-depth interviews. Through thematic analyses, we identified and compared privacy/confidentiality concerns associated with two survey methods that (1) collect self-reported addresses/cross-streets and (2) use an interactive web-based map to find/confirm locations in rural and urban settings.

RESULTS

Concerns differed more by setting than between methods. For example, (1) rural participants valued interviewer rapport and protections provided by the Certificate of Confidentiality more; (2) locations considered to be sensitive differed in rural (i.e., others' homes) and urban (i.e., where drugs were used) settings; and (3) urban participants were more likely to view providing cross-streets as an acceptable alternative to providing exact addresses for sensitive locations and to prefer the web-based map approach.

CONCLUSION

Rural-urban differences in privacy/confidentiality concerns reflect contextual differences (i.e., where drugs are used/purchased, population density, and prior drug-related arrests). Strategies to alleviate concerns include: (1) obtain a Certificate of Confidentiality, (2) collect geographic data at the scale necessary for proposed analyses, and (3) permit participants to provide intersections/landmarks in close proximity to actual locations rather than exact addresses or to skip questions where providing an intersection/landmark would not obfuscate the actual address.

Examining the Social Context of Injection Drug Use: Social Proximity to Persons Who Inject Drugs Versus Geographic Proximity to Persons Who Inject Drugs

In this analysis, we used social network and spatial data to examine associations between people's drug injection status and their social and/or spatial proximity to others who injected drugs. We recruited 503 rural Kentucky residents who used drugs to participate in the Social Networks among Appalachian People (SNAP) Study (2008-2010). Interviewer-administered surveys collected information on recent (past 6 months) sex, drug-use, and social-support network members (n = 897 ties). Using network simulations, we determined a threshold for the association between social proximity to others who injected drugs and recent injection status ("socially proximal" was defined by a shortest path ≤2). We defined "geographically proximal" as the median road-network distance between pairs of individuals who both injected drugs (≤7 miles (≤11.2 km)). Logistic regression was used to determine the independent and joint associations between the number of socially and/or geographically proximal injecting peers and a person's injection status. After adjustment, the odds of recent injection increased by 0.4% for each injecting peer who was geographically proximal but not socially proximal, 12% for each geographically and socially proximal injecting peer, and 22% for each injecting peer who was socially proximal but not geographically proximal. When implementing network-based interventions which promote cessation of injection drug use, investigators should consider collecting sociometric network data to examine whether the intervention diffuses through the network and whether there are additive or threshold effects.

Healthcare contact and treatment uptake following hepatitis C virus screening and counseling among rural Appalachian people who use drugs

BACKGROUND

Hepatitis C virus (HCV) remains a major contributor to morbidity and mortality worldwide. Since 2009, Kentucky has led the United States in cases of acute HCV, driven largely by injection drug use in rural areas. Improved treatment regimens hold promise of mitigating the impact and transmission of HCV, but numerous barriers obstruct people who inject drugs (PWID) from receiving care, particularly in medically underserved settings.

METHODS

503 rural people who use drugs were recruited using respondent-driven sampling and received HCV screening and post-test counseling. Presence of HCV antibodies was assessed using enzyme immunoassay of dried blood samples. Sociodemographic and behavioral data were collected using computer-based questionnaires. Predictors of contacting a healthcare provider for follow-up following HCV-positive serotest and counseling were determined using discrete-time survival analysis.

RESULTS

150 (59%) of 254 participants reported contacting a healthcare provider within 18 months of positive serotest and counseling; the highest probability occurred within six months of serotesting. 35 participants (14%) reported they were seeking treatment, and 21 (8%) reported receiving treatment. In multivariate time-dependent modeling, health insurance, internet access, prior substance use treatment, meeting DSM-IV criteria for generalized anxiety disorder, and recent marijuana use increased the odds of making contact for follow-up. Participants meeting criteria for major depressive disorder and reporting prior methadone use, whether legal or illegal, were less likely to contact a provider.

CONCLUSION

While only 8% received treatment after HCV-positive screening, contacting a healthcare provider was frequent in this sample of rural PWID, suggesting that the major barriers to care are likely further downstream. These findings offer insight into the determinants of engaging the cascade of medical treatment for HCV and ultimately, treatment-as-prevention. Further study and increased resources to support integrated interventions with effectiveness in other settings are recommended to mitigate the impact of HCV in this resource-deprived setting.

A mixed methods study of HIV-related services in buprenorphine treatment

BACKGROUND

Opioid use disorder (OUD) is a major risk factor in the acquisition and transmission of HIV. Clinical practice guidelines call for the integration of HIV services in OUD treatment. This mixed methods study describes the integration of HIV services in buprenorphine treatment and examines whether HIV services vary by prescribers' medical specialty and across practice settings.

METHODS

Data were obtained via qualitative interviews with buprenorphine experts (n = 21) and mailed surveys from US buprenorphine prescribers (n = 1174). Survey measures asked about screening for HIV risk behaviors at intake, offering HIV education, recommending all new patients receive HIV testing, and availability of on-site HIV testing. Prescribers' medical specialty, practice settings, caseload demographics, and physician demographics were measured. Multivariate models of HIV services were estimated, while accounting for the nesting of physicians within states.

RESULTS

Qualitative interviews revealed that physicians often use injection behaviors as the primary indicator for whether a patient should be tested for HIV. Interviews revealed that HIV-related services were often viewed as beyond the scope of practice among general psychiatrists. Surveys indicated that prescribers screened for an average of 3.2 of 5 HIV risk behaviors (SD = 1.6) at intake. About 62.0% of prescribers delivered HIV education to patients and 53.2% recommended HIV testing to all new patients, but only 32.3% offered on-site HIV testing. Addiction specialists and psychiatrists screened for significantly more HIV risk behaviors than physicians in other specialties. Addiction specialists and psychiatrists were significantly less likely than other physicians to offer on-site testing. Physicians in individual medical practice were significantly less likely to recommend HIV testing and to offer onsite testing than physicians in other settings.

CONCLUSIONS

Buprenorphine treatment providers have not uniformly integrated HIV-related screening, education, and testing services for patients. Differences by medical specialty and practice setting suggest an opportunity for targeting efforts to increase implementation.

Buprenorphine physician supply: Relationship with state-level prescription opioid mortality

BACKGROUND

Buprenorphine is an effective treatment for opioid use disorder but the supply of buprenorphine physicians is currently inadequate to address the nation's prescription opioid crisis. Perception of need due to rising opioid overdose rates is one possible reason for physicians to adopt buprenorphine. This study examined associations between rates of growth in buprenorphine physicians and prescription opioid overdose mortality rates in US states.

METHODS

The total buprenorphine physician supply and number of physicians approved to treat 100 patients (per 100,000 population) were measured from June 2013 to January 2016. States were divided into two groups: those with rates of prescription opioid overdose mortality in 2013 at or above the median (>5.5 deaths per 100,000 population) and those with rates below the median. State-level growth curves were estimated using mixed-effects regression to compare rates of growth between high and low overdose states.

RESULTS

The total supply and the supply of 100-patient buprenorphine physicians grew significantly (total supply from 7.7 to 9.9 per 100,000 population, p<0.001; 100-patient supply from 2.2 to 3.4 per 100,000 population, p<0.001). Rates of growth were significantly greater in high overdose states when compared to low overdose states (total supply b=0.033, p<0.01; 100-patient b=0.022, p<0.01).

CONCLUSIONS

The magnitude of the US prescription opioid crisis, as measured by the rate of prescription opioid overdose mortality, is associated with growth in the number of buprenorphine physicians. Because this observational design cannot establish causality, further research is needed to elucidate the factors influencing physicians' decisions to begin prescribing buprenorphine.

African American women and sexually transmitted infections: The contextual influence of unbalanced sex ratios and individual risk behaviors

This study uses data from 564 African American women to examine the correlates of lifetime prevalence of a sexually transmitted infection (STI). Specifically, we test the effects of perceptions about the availability of African American males, five partner characteristics, and drug history. At the bivariate-level, women with an STI diagnosis were significantly more likely to have dated a man who was married, older, had sex with another man, involved in concurrent partnerships, and had been incarcerated. About half of the participants stated it was difficult to find an eligible African American male and attributed the limited pool of same-race partners to drug trafficking, a lack of monogamy, and high rates of incarceration. Multivariate analyses revealed having dated a man who had concurrent sexual partnerships or had been incarcerated, as well as drug use during sex were positively associated with ever having an STI. Individual and contextual implications are addressed.

"I'm Stuck": Women's Navigations of Social Networks and Prescription Drug Misuse in Central Appalachia

This study utilizes anthropological analyses of kinship, care, gendered inequalities, and the state to examine how social networks affect women's substance use in a rural Appalachian county where the primary drug of choice is prescription opioids. Of 503 participants from a larger study of social networks among rural drug users, 16 women who reported using drugs with four or more other study participants (drug network members) were interviewed from November 2011 to February 2012. The purpose of interviews is to analyze the substance use patterns among participants who are highly connected in their networks. Female participants say they feel "stuck" in cycles of prescription drug misuse because of entrenchment in moral economies, intensive caretaking responsibilities, and violence from those in their networks. Although women demonstrate agency in their navigations of drug use, relationships, and economic and health inequalities, the factors that constrain women's actions culminate to create barriers for women accessing substance abuse treatment or decreasing substance use outside of treatment. This study adds to understandings of the relational and situational aspects of women's drug use and efforts to decrease use. Recognizing these aspects of women's lives will aid policies and programs in becoming more relevant to substance abusing women. (substance use; kinship; care; gendered inequalities; Appalachia).

Accuracy of name and age data provided about network members in a social network study of people who use drugs: implications for constructing sociometric networks

PURPOSE

Network analysis has become increasingly popular in epidemiologic research, but the accuracy of data key to constructing risk networks is largely unknown. Using network data from people who use drugs (PWUDs), the study examined how accurately PWUD reported their network members' (i.e., alters') names and ages.

METHODS

Data were collected from 2008 to 2010 from 503 PWUD residing in rural Appalachia. Network ties (n = 897) involved recent (past 6 months) sex, drug cousage, and/or social support. Participants provided alters' names, ages, and relationship-level characteristics; these data were cross-referenced to that of other participants to identify participant-participant relationships and to determine the accuracy of reported ages (years) and names (binary).

RESULTS

Participants gave alters' exact names and ages within two years in 75% and 79% of relationships, respectively. Accurate name was more common in relationships that were reciprocally reported and those involving social support and male alters. Age was more accurate in reciprocal ties and those characterized by kinship, sexual partnership, recruitment referral, and financial support, and less accurate for ties with older alters.

CONCLUSIONS

Most participants reported alters' characteristics accurately, and name accuracy was not significantly different in relationships involving drug-related and/or sexual behavior compared to those not involving these behaviors.

Gabapentin misuse, abuse and diversion: a systematic review

BACKGROUND AND AIMS

Since its market release, gabapentin has been presumed to have no abuse potential and subsequently has been prescribed widely off-label, despite increasing reports of gabapentin misuse. This review estimates and describes the prevalence and effects of, motivations behind and risk factors for gabapentin misuse, abuse and diversion.

METHODS

Databases were searched for peer-reviewed papers demonstrating gabapentin misuse, characterized by taking a larger dosage than prescribed or taking gabapentin without a prescription, and diversion. All types of studies were considered; grey literature was excluded. Thirty-three papers met inclusion criteria, consisting of 23 case studies and 11 epidemiological reports. Published reports came from the United States, the United Kingdom, Germany, Finland, India, South Africa and France, and two analyzed websites not specific to a particular country.

RESULTS

Prevalence of gabapentin misuse in the general population was reported to be 1%, 40-65% among individuals with prescriptions and between 15 and 22% within populations of people who abuse opioids. An array of subjective experiences reminiscent of opioids, benzodiazepines and psychedelics were reported over a range of doses, including those within clinical recommendations. Gabapentin was misused primarily for recreational purposes, self-medication or intentional self-harm and was misused alone or in combination with other substances, especially opioids, benzodiazepines and/or alcohol. Individuals with histories of drug abuse were most often involved in its misuse.

CONCLUSIONS

Epidemiological and case report evidence suggests that the anti-epileptic and analgesic medication gabapentin is being misused internationally, with substance abuse populations at special risk for misuse/abuse.

Individual and Network Correlates of Antisocial Personality Disorder Among Rural Nonmedical Prescription Opioid Users

PURPOSE

Examination of the association of antisocial personality disorder (ASPD) with substance use and HIV risk behaviors within the social networks of rural people who use drugs.

METHODS

Interviewer-administered questionnaires were used to assess substance use, HIV risk behavior, and social network characteristics of drug users (n = 503) living in rural Appalachia. The MINI International Psychiatric Interview was used to determine whether participants met DSM-IV criteria for ASPD and Axis-I psychological comorbidities (eg, major depressive disorder, posttraumatic stress disorder, generalized anxiety disorder). Participants were also tested for herpes simplex 2, hepatitis C, and HIV. Multivariate generalized linear mixed modeling was used to determine the association between ASPD and risk behaviors, substance use, and social network characteristics.

RESULTS

Approximately one-third (31%) of participants met DSM-IV criteria for ASPD. In multivariate analysis, distrust and conflict within an individual's social networks, as well as past 30-day use of heroin and crack, male gender, younger age, lesser education, heterosexual orientation, and comorbid MDD were associated with meeting diagnostic criteria for ASPD.

CONCLUSIONS

Participants meeting criteria for ASPD were more likely to report recent heroin and crack use, which are far less common drugs of abuse in this population in which the predominant drug of abuse is prescription opioids. Greater discord within relationships was also identified among those with ASPD symptomatology. Given the elevated risk for blood-borne infection (eg, HIV) and other negative social and health consequences conferred by this high-risk subgroup, exploration of tailored network-based interventions with mental health assessment is recommended.

States' implementation of the Affordable Care Act and the supply of physicians waivered to prescribe buprenorphine for opioid dependence

BACKGROUND

Although the Affordable Care Act (ACA) is anticipated to affect substance use disorder (SUD) treatment, its impact on the supply of physicians waivered to treat opioid dependence with buprenorphine has not been considered. This study examined whether states more supportive of ACA, meaning those that had opted to expand Medicaid and establish a state-based health insurance exchange, experienced greater growth in physician supply than less supportive states.

METHODS

Buprenorphine physician supply, including total physician supply, supply of 30-patient physicians, and supply of 100-patient physicians per 100,000 state residents, was measured from June 2013 to May 2015. State characteristics were drawn from multiple secondary sources, with states categorized as ACA-supportive, ACA-hybrid (where states either expanded Medicaid or established a state-based exchange), or ACA-resistant (where states took neither action). Mixed effects regression was used to estimate state-level growth curves to test whether rates of growth varied by states' approaches to implementing ACA.

RESULTS

The supply of waivered physicians grew significantly over the two-year period. Rates of growth were significantly lower in ACA-hybrid and ACA-resistant states relative to growth in ACA-supportive states. Average buprenorphine physician supply at baseline varied by region, the percentage of residents covered by Medicaid, and the supply of specialty SUD treatment programs.

CONCLUSIONS

This study found a positive impact of the ACA on growth in the supply of buprenorphine-waivered physicians in US states. Future research should address whether the ACA affects the number of patients receiving buprenorphine, Medicaid spending, and the quality of treatment services delivered.

Correlates to seroprevalent herpes simplex virus type 2 among rural Appalachian drug users

Herpes simplex virus type 2 (HSV-2) is the most common cause of genital ulcer disease and, along with substance abuse, an important HIV risk factor. Therefore, the purpose of this study was to examine HSV-2 seroprevalence in a sample of drug users in rural Appalachia. Rural Appalachian individuals age 18 or older reporting non-medical use of prescription opioids, heroin, crack/cocaine, or methamphetamine in the past 6 months (n = 499) were included. Behavioral, demographic, and sexual network data were collected using interviewer-administered questionnaires. Participants' serum was tested for HSV-2 antibodies using the Biokit rapid test (Lexington, MA). The estimated population seroprevalence of HSV-2 was 14.4% (95%CI: 9.6-19.4%). Only 8.8% were aware of being HSV-2+, and unprotected sex was reported in 80% of serodiscordant sexual relationships. In a multivariate model, female gender, age, older age at first oral sex, and frequency of unprotected sex in the sexual network were independently associated with HSV-2 seropositivity. Despite lower seroprevalence than that reported in similar studies of substance abusers, targeted interventions to reduce sexual risk behavior are warranted in this underserved population. Network-informed approaches with particular focus on women, older individuals, and those engaging in frequent unprotected sex are recommended.

Relationship-level analysis of drug users' anticipated changes in risk behavior following HIV vaccination

Formative research into the behavioral factors surrounding HIV vaccine uptake is becoming increasingly important as progress is made in HIV vaccine development. Given that the first vaccines on the market are likely to be partially effective, risk compensation (i.e., increased risk behavior following vaccination) may present a concern. This study characterized the relationships in which HIV vaccine-related risk compensation is most likely to occur using dyadic data collected from people who use drugs, a high-risk group markedly underrepresented in extant literature. Data were collected from 433 drug users enrolled in a longitudinal study in the USA. Respondents were asked to provide the first name and last initial of individuals with whom they had injected drugs and/or had sex during the past six months. For each partner, respondents reported their likelihood of increasing risk behavior if they and/or their partner received an HIV vaccine. Using generalized linear mixed models, relationship-level correlates to risk compensation were examined. In bivariate analysis, risk compensation was more likely to occur between partners who have known each other for a shorter time (odds ratio [OR]=0.95, 95% confidence interval [CI]: 0.90-0.99, p=0.028) and between those who inject drugs and have sex together (OR=2.52, CI: 1.05-6.04, p=0.039). In relationships involving risk compensation, 37% involved partners who had known each other for a year or less compared to only 13% of relationships not involving risk compensation. Adjusting for other variables, duration (OR: 0.95, CI: 0.90-1.00, p=0.033) was associated with risk compensation intent. These analyses suggest that risk compensation may be more likely to occur in less established relationships and between partners engaging in more than one type of risk behavior. These data provide further support for the need to expand measures of risk compensation in HIV vaccine preparedness studies to assess not only if people will change their behavior, but also with whom.

Drug use, hepatitis C, and service availability: perspectives of incarcerated rural women

This study examined drug use, hepatitis C, and service availability and use among a high-risk sample of rural women serving time in jails. Data was collected from female offenders (N = 22) who participated in four focus groups in three rural jail facilities located in Appalachia. Findings indicated that drug misuse is prevalent in this impoverished area of the country, and that the primary route of administration of drug use is injection. Findings also indicate that injection drug use is also commonly associated with contracting hepatitis C (HCV), which is also perceived to be prevalent in the area. Despite knowledge associated with HCV risks, women in this sample were seemingly apathetic about the increasing spread of HCV in the area and unconcerned about the long-term consequences of the course of the infection. Implications for future research and practice are discussed.

Hepatitis C vaccine clinical trials among people who use drugs: potential for participation and involvement in recruitment

Candidate prophylactic HCV vaccines are approaching phase III clinical trial readiness, yet little is known about the potential for participation among target groups or innovative ways to promote enrollment within 'hard-to-reach' populations. This study describes HCV vaccine trial participation willingness among a high-risk sample of people who use drugs and their willingness to assist researchers by promoting the trial among peers. Willingness to participate in and encourage peers' participation in an HCV vaccine trial was assessed among injection and non-injection drug users enrolled in a cohort study in Kentucky using interviewer-administered questionnaires (n=165 and 415, respectively, with willingness to participate assessed among HCV-seronegative participants only). Generalized linear mixed models were used to determine correlates to being "very likely" to participate or encourage participation in a trial. Most reported being likely to participate or encourage participation in a vaccine trial (63% and 87%, respectively). Men were significantly less likely to report willingness to encourage others' participation, while willingness to encourage was higher among lower income, HCV-seropositive, heroin-using, and methamphetamine-using participants. Unemployment, lesser education, receipt of financial support from more peers, and nonmedical prescription drug use were positively associated with willingness to participate. Differential enrollment in HCV vaccine clinical trials by socioeconomic status may occur, underscoring ethical considerations and need for avoiding coercion. Notably, the data suggest that a peer-driven approach to promoting trial participation among people who use drugs could be feasible in this population and that HCV-seropositive individuals and women could be especially instrumental in these efforts.

Will HIV vaccination reshape HIV risk behavior networks? A social network analysis of drug users' anticipated risk compensation

BACKGROUND

An HIV vaccine could substantially impact the epidemic. However, risk compensation (RC), or post-vaccination increase in risk behavior, could present a major challenge. The methodology used in previous studies of risk compensation has been almost exclusively individual-level in focus, and has not explored how increased risk behavior could affect the connectivity of risk networks. This study examined the impact of anticipated HIV vaccine-related RC on the structure of high-risk drug users' sexual and injection risk network.

METHODS

A sample of 433 rural drug users in the US provided data on their risk relationships (i.e., those involving recent unprotected sex and/or injection equipment sharing). Dyad-specific data were collected on likelihood of increasing/initiating risk behavior if they, their partner, or they and their partner received an HIV vaccine. Using these data and social network analysis, a "post-vaccination network" was constructed and compared to the current network on measures relevant to HIV transmission, including network size, cohesiveness (e.g., diameter, component structure, density), and centrality.

RESULTS

Participants reported 488 risk relationships. Few reported an intention to decrease condom use or increase equipment sharing (4% and 1%, respectively). RC intent was reported in 30 existing risk relationships and vaccination was anticipated to elicit the formation of five new relationships. RC resulted in a 5% increase in risk network size (n = 142 to n = 149) and a significant increase in network density. The initiation of risk relationships resulted in the connection of otherwise disconnected network components, with the largest doubling in size from five to ten.

CONCLUSIONS

This study demonstrates a new methodological approach to studying RC and reveals that behavior change following HIV vaccination could potentially impact risk network connectivity. These data will be valuable in parameterizing future network models that can determine if network-level change precipitated by RC would appreciably impact the vaccine's population-level effectiveness.

The impact of a reformulation of extended-release oxycodone designed to deter abuse in a sample of prescription opioid abusers

BACKGROUND

Prescription opioid abuse is a significant public health concern that requires strategies to reduce its impact, including development of abuse deterrent formulations. OxyContin, an extended-release oxycodone (ERO) formulation, has been widely abused. This study assessed the effects of reformulated ERO, designed to be more difficult to manipulate for purposes of intranasal and intravenous abuse, on patterns of opioid abuse among a sample of individuals from rural Appalachia with a history of ERO abuse.

METHODS

Structured interviews assessing opioid abuse (past 30-day abuse and retrospectively reported abuse prior to the reformulation in August 2010) were completed by 189 individuals between December 2010 and September 2011.

RESULTS

The past 30-day prevalence and frequency of reformulated ERO abuse through any route (33%, 1.9 days/month), snorting (5%, 0.2 days/month), and injecting (0.5%, <0.1 days/month) were low and infrequent compared to that of IR oxycodone (any route: 96%, 19.5 days/month; snorting: 70%, 10.3 days/month; injecting: 51%, 10.5 days/month) and retrospectively reported abuse of original ERO in August 2010 (any route: 74%, 13.4 days/month; snorting: 39%, 6.0 days/month; injecting: 41%, 8.6 days/month). After the reformulation, the prevalence of original ERO abuse significantly declined while abuse of reformulated ERO remained steadily low. Heroin abuse was rare in this sample.

CONCLUSIONS

In this sample, abuse of reformulated ERO was low, and lower than abuse of original ERO retrospectively and IR oxycodone concurrently, particularly through injecting and snorting routes of administration. There was no evidence to suggest that reformulated ERO became a substitute for original ERO.