Danielle C. Ompad

Urban as a determinant of health

Cities are the predominant mode of living, and the growth in cities is related to the expansion of areas that have concentrated disadvantage. The foreseeable trend is for rising inequities across a wide range of social and health dimensions. Although qualitatively different, this trend exists in both the developed and developing worlds. Improving the health of people in slums will require new analytic frameworks. The social-determinants approach emphasizes the role of factors that operate at multiple levels, including global, national, municipal, and neighborhood levels, in shaping health. This approach suggests that improving living conditions in such arenas as housing, employment, education, equality, quality of living environment, social support, and health services is central to improving the health of urban populations. While social determinant and multilevel perspectives are not uniquely urban, they are transformed when viewed through the characteristics of cities such as size, density, diversity, and complexity. Ameliorating the immediate living conditions in the cities in which people live offers the greatest promise for reducing morbidity, mortality, and disparities in health and for improving quality of life and well being.

Prospective Evaluation of Community-Acquired Acute-Phase Hepatitis C Virus Infection

BACKGROUND More than two-thirds of hepatitis C virus (HCV) infections in Western countries are caused by injection drug use, but prospective clinical data regarding the most common mode of HCV acquisition are rare, in part because acute-phase HCV infection is usually asymptomatic. METHODS To characterize acute-phase HCV infection, 179 HCV antibody-negative injection drug users were prospectively evaluated; 62 (34%) of these patients had seroconverted. Twenty of the participants who seroconverted had long-term follow-up with consistent monthly sampling before and after seroconversion, allowing detailed study. RESULTS The first indication of HCV infection was the presence of HCV RNA in serum, which preceded elevation of alanine transaminase levels and total bilirubin levels to > or =2 times baseline in 45% and 77% of patients, respectively. No subjects had jaundice. The median time from initial viremia to seroconversion was 36 days (range, 32-46 days). In one instance, viremia was detected 434 days before seroconversion. However, in no other case was HCV RNA detected >63 days before seroconversion. In subjects with viral persistence, a stable level of HCV RNA in the blood was noted in some subjects within 60 days after the initial detection of viremia, but in others, it was not apparent until >1 year later. In subjects with long-term viral clearance, HCV became persistently undetectable as early as 94 and as late as 620 days after initial viremia. CONCLUSIONS These data underscore the importance of nucleic acid screening of blood donations to prevent HCV transmission and of long-term follow-up to ascertain whether there is viral persistence, at least among injection drug users.

Childhood sexual abuse and age at initiation of injection drug use

OBJECTIVES We examined the relation between childhood sexual abuse and injection drug use initiation among young adult injection drug users. METHODS We used mixed effect linear models to compare age at first injection among 2143 young injection drug users by first sexual abuse age categories. RESULTS The participants were predominantly male (63.3%) and White (52.8%). Mean age and age at first injection were 23.7 and 19.6 years, respectively; 307 participants (14.3%) reported childhood sexual abuse. After adjustment for gender, race/ethnicity, noninjection drug use before first injection drug use, and recruitment site, childhood sexual abuse was independently associated with younger age at first injection. CONCLUSIONS Childhood sexual abuse was associated with earlier initiation of injection drug use. These data emphasize the need to integrate substance abuse prevention with postvictimization services for children and adolescents.

Factors associated with adolescent initiation of injection drug use

Objective. The purpose of this study was to evaluate the extent to which demographic, sexual, and non-injection drug use practices predict adolescent initiation of injection drug use. Methods. Street recruited injection drug users 15–30 years of age in Baltimore, Maryland, who initiated injection within five years of study enrollment, completed a questionnaire that included a year-by-year history regarding the five years prior to initiation of injection. Factors associated with initiation during adolescence (≤21 years of age) versus young adult-hood (>21) were determined using logistic regression. Results. Of 226 participants, most were female (61%) and African American (64%). Median age of participants was 25; median age at initiation of injection was 23. Factors significantly associated with adolescent initiation in multivariate analysis included race other than African American, and practices prior to initiating injection including condom use, lack of cocaine use, exclusive crack smoking just prior to initiation, and smoking marijuana. Adolescent initiates also had shorter durations of illicit drug use prior to initiating injection. Conclusion. Short-term non-injection drug use, particularly exclusive crack smoking, was associated with adolescent initiation of injection drug use. Early prevention efforts targeting this high-risk group of younger drug users are warranted in order to delay or prevent onset of injection drug use.

Access to and Use of Health Services Among Undocumented Mexican Immigrants in a US Urban Area

OBJECTIVES We assessed access to and use of health services among Mexican-born undocumented immigrants living in New York City in 2004. METHODS We used venue-based sampling to recruit participants from locations where undocumented immigrants were likely to congregate. Participants were 18 years or older, born in Mexico, and current residents of New York City. The main outcome measures were health insurance coverage, access to a regular health care provider, and emergency department care. RESULTS In multivariable models, living in a residence with fewer other adults, linguistic acculturation, higher levels of formal income, higher levels of social support, and poor health were associated with health insurance coverage. Female gender, fewer children, arrival before 1997, higher levels of formal income, health insurance coverage, greater social support, and not reporting discrimination were associated with access to a regular health care provider. Higher levels of education, higher levels of formal income, and poor health were associated with emergency department care. CONCLUSIONS Absent large-scale political solutions to the challenges of undocumented immigrants, policies that address factors shown to limit access to care may improve health among this growing population.

Effects of Race, Neighborhood, and Social Network on Age at Initiation of Injection Drug Use

OBJECTIVES We investigated individual- and neighborhood-level factors associated with adolescent initiation of injection drug use. METHODS Injection drug users (IDUs) who had been injecting 2 to 5 years underwent HIV testing and completed a sociobehavioral risk survey. Modeling techniques accounting for intraneighborhood correlations were used in data analyses. RESULTS Adolescent-initiating IDUs were less likely than adult-initiating IDUs to report high-risk sex and injection behaviors and more likely to report high-risk networks. African American IDUs from neighborhoods with large percentages of minority residents and low adult educational levels were more likely to initiate injection during adolescence than White IDUs from neighborhoods with low percentages of minority residents and high adult education levels. CONCLUSIONS Racial segregation and neighborhood-level educational attainment must be considered when drawing inferences about age at initiation of injection drug use and related high-risk behaviors.

Social circumstances of initiation of injection drug use and early shooting gallery attendance: implications for HIV intervention among adolescent and young adult injection drug users.

To determine correlates of early shooting gallery (SG) attendance and HIV prevalence and incidence among new injection drug users (IDUs), baseline data from a prospective cohort study of street-recruited IDUs aged 15 to 30 years and injecting ≤5 years were used to identify early high-risk practices and salient social circumstances associated with early SG attendance to help in the design of innovative intervention strategies. Of 226 IDUs, 10.6% were HIV-seropositive, and HIV incidence was 6.6 per 100 person-years (95% CI: 2.2–13.3). Median age was 25 years, and most participants were African American (64%) and female (61%). Using multiple logistic regression, early SG attendees were three times as likely to be HIV-seropositive and twice as likely to be initiated by an older IDU. Early SG attendees were also five times more likely to share injection equipment and over three times more likely to report a high-risk injecting network soon after initiating injection. These data suggest that young new IDUs who attend SGs early tend to be initiated by older high-risk IDUs and to share and inject within a high-risk social setting early on as well. Hence, older IDUs may serve as a bridge group to SGs, transmitting HIV from older to younger IDUs.

Identifying Injection Drug Users at Risk of Nonfatal Overdose

OBJECTIVES Drug overdose is the second leading cause of accidental deaths among U.S. adults aged 15-64 years. Emergency physicians have a unique opportunity to provide overdose prevention interventions, because habitual drug users are in frequent need of medical care. The authors evaluated associations between individual-level risk factors and experiencing an overdose in the past six months to determine which characteristics and behaviors may be most predictive of overdose. METHODS The authors used data from a sample of street-recruited habitual drug users who participated in face-to-face interviews about overdose from November 2001 to February 2004. This analysis was restricted to 772 respondents who had been injecting for at least one year and who had injected heroin within the past two months. RESULTS A total of 16.6% of participants had overdosed in the past six months. Characteristics and behaviors that were independently associated with an increased risk of a recent overdose were having had a prior overdose (odds ratio [OR], 28.58; 95% confidence interval [CI] = 14.10 to 57.96), using cocaine/crack in the past six months (OR, 2.07; 95% CI = 1.25 to 3.45), using alcohol in the past six months (OR, 1.90; 95% CI = 1.01 to 3.57), experiencing serious withdrawal symptoms in the past two months (OR, 2.70; 95% CI = 1.58 to 4.61), and younger age. CONCLUSIONS Drug users who have previously experienced a nonfatal overdose are at very high risk of experiencing future overdoses. Further longitudinal studies are needed to identify robust predictors of overdose risk over time in habitual drug users, but these data suggest that drug users who have overdosed warrant aggressive prevention efforts such as agonist maintenance treatment or provision of take-home naloxone.

Updating the Infection Risk Reduction Hierarchy: Preventing Transition into Injection

Current approaches to prevention of blood-borne infections in injection drug users include referral to drug abuse treatment, access to sterile syringes, bleach disinfection of injection equipment, and education about not sharing equipment. However, rates of some blood-borne infections (e.g., hepatitis C virus) remain elevated among injection drug users, especially early after initiation into injection drug use. With lower infection rates in noninjectors and transition into injection drug use occurring most commonly among these noninjectors, prevention of transition into injection drug use as an additional step to reduce risk for acquisition and transmission of blood-borne infections merits closer attention.

HIV Prevalence, Risk Behaviors, and High-Risk Sexual and Injection Networks Among Young Women Injectors Who Have Sex With Women

Women injection drug users who have sex with women (WSW IDUs) constitute 20% to 30% of American women IDUs.1 Compared with other women IDUs, WSW IDUs have higher HIV prevalence and incidence rates and a greater likelihood of engaging in high-risk injection and sexual practices with men.1–16 Previous reports suggested that WSW IDUs may be particularly likely to engage in drug injection and sex with men who have sex with men (MSM)1,2,5,6,9,17–19 and to be subordinated and isolated within drug users’ social milieus and more generally.1,20,21 Historical and generational factors may have changed some relationships as a consequence of the HIV epidemic itself, however. Ethnographic data from New York City and Boston, Mass, suggest that many older MSM IDUs and WSW IDUs who injected drugs together may have died earlier in the epidemic, which might reduce the extent to which WSW IDUs currently engage in drug injection and sex with MSM. To further examine HIV risk among WSW IDUs, we compared social situations, injection and sexual networks, and behaviors of young WSW IDUs with those of other young women IDUs.