Biomedical subjects

James M McMahon

Publications and source records attributed to James M McMahon.

9 recordsLinked to original sources

PubMed2006

Syringe disposal among injection drug users in Harlem and the Bronx during the New York State Expanded Syringe Access Demonstration Program.

Effective January 1, 2001, New York State enacted the Expanded Syringe Access Demonstration Program (ESAP), allowing syringes to be sold in pharmacies without a prescription or dispensed through doctors, hospitals, and clinics to adults. A concern in the assessment of ESAP is its effects on syringe disposal practices. Syringe use data regarding the last injection episode were combined from three projects (N = 1,030) recruiting injection drug users. Disposal of syringes by methods known to be safe decreased significantly over time after the implementation of ESAP. Syringes obtained either from syringe exchange programs or ESAP sources were more likely to be disposed of safely than syringes obtained from other sources. Efforts to enlist pharmacists and others involved in ESAP implementation to encourage safe disposal are needed. More detailed information on disposal practices is needed to capture the continuum from least to most safe practices and variation within individuals.

Adolescent↗

PubMed2006

Contextual determinants of condom use among female sex exchangers in East Harlem, NYC: an event analysis.

Recent studies have revealed a variety of contexts involving HIV risk behaviors among women who exchange sex for money or drugs. Event analysis was used to identify the individual, relationship, and contextual factors that contribute to these high-risk sex exchange practices. Analyses were conducted on data obtained from 155 drug-using women who reported details of their most recent sex exchange event with male clients. The majority of sex exchange encounters (78%) involved consistent condom use. In multivariable analysis, protective behavior was associated primarily with situational and relationship variables, such as exchange location, substance use, sexual practices, and respondent/client discussion and control. In order to inform HIV prevention programs targeted to women sex exchangers, further research is needed on the contextual determinants of risk, especially with regard to condom-use negotiation and factors involving substance use that adversely affect women's ability to manage protective behavior in the context of sex exchange.

Adult↗

PubMed2006

A guide for multilevel modeling of dyadic data with binary outcomes using SAS PROC NLMIXED.

In the social and health sciences, data are often structured hierarchically, with individuals nested within groups. Dyads constitute a special case of hierarchically structured data with variation at both the individual and dyadic level. Analyses of data from dyads pose several challenges due to the interdependence between members within dyads and issues related to small group sizes. Multilevel analytic techniques have been developed and applied to dyadic data in an attempt to resolve these issues. In this article, we describe a set of analyses for modeling individual- and dyad-level influences on binary outcomes using SAS statistical software; and we discuss the benefits and limitations of such an approach. For illustrative purposes, we apply these techniques to estimate individual-dyad-level predictors of viral hepatitis C infection among heterosexual couples in East Harlem, New York City.

Journal Article↗

PubMed2005

Receptive syringe sharing among injection drug users in Harlem and the Bronx during the New York State Expanded Syringe Access Demonstration Program.

BACKGROUND: Effective on January 1, 2001, New York State enacted the Expanded Syringe Access Demonstration Program (ESAP), which allows syringes to be sold in pharmacies without a prescription or dispensed through doctors, hospitals, and clinics to persons 18 years of age or older and permits the possession of those syringes for the purposes of injecting drugs. OBJECTIVE: To assess changes in receptive syringe sharing since the inception of the ESAP. METHODS: Sociodemographic characteristics and syringe use data regarding the last injection episode were combined from 3 projects (n = 1181) recruiting injection drug users in ongoing studies in Harlem and the Bronx in New York City from January 2001 through June 2003. These data were analyzed as serial cross sections by calendar quarter. RESULTS: Receptive sharing decreased significantly over time, from 13.4% in the first quarter to 3.6% in the last quarter. Obtaining the last injection syringe from an ESAP source (mostly pharmacies) increased significantly over time, from 7.5% in the first quarter to 25.0% in the last quarter. In multiple logistic regression analysis, variables that were significantly associated with less receptive sharing were syringe exchange and ESAP syringe source as well as time since ESAP inception. Female gender and white race/ethnicity were significantly associated with greater receptive sharing. CONCLUSIONS: The increase in the use of pharmacies and other ESAP syringe sources in this sample has been accompanied by a decline in receptive sharing.

Adult↗

PubMed2004

Detection of hepatitis C virus in the nasal secretions of an intranasal drug-user.

BACKGROUND: One controversial source of infection for hepatitis C virus (HCV) involves the sharing of contaminated implements, such as straws or spoons, used to nasally inhale cocaine and other powdered drugs. An essential precondition for this mode of transmission is the presence of HCV in the nasal secretions of intranasal drug users. METHODS: Blood and nasal secretion samples were collected from five plasma-positive chronic intranasal drug users and tested for HCV RNA using RT-PCR. RESULTS: HCV was detected in all five blood samples and in the nasal secretions of the subject with the highest serum viral load. CONCLUSIONS: This study is the first to demonstrate the presence of HCV in nasal secretions. This finding has implications for potential transmission of HCV through contact with contaminated nasal secretions.

Journal Article↗

PubMed2004

Sharing of noninjection drug-use implements as a risk factor for hepatitis C.

This study examined sharing noninjection drug implements as a risk factor for hepatitis C (HCV) infection among women drug users (n = 123) with no history of drug injection. Participants were street-recruited from East Harlem, New York City, between October 1997 and June 1999. Participants were administered a survey measuring risk factors for HCV. Prevalence of HCV and HIV infections was 19.5% and 14.6%, respectively. Multiple logistic regression determined significant associations between sharing noninjection drug-use implements and HCV infection. "Ever shared both oral and intranasal noninjection drug implements" was independently associated with HCV infection [Odds ratio (OR) 2.83; Confidence interval (CI) 1.04, 7.72; p = 0.04]; "ever shared noninjected heroin implements with an injector" was a trend (OR 3.06; CI .85, 10.79; p = 0.08). The strongest association between sharing noninjection drug-use implements and HCV infection was found among HIV positive individuals (chi2 = 8.8, 1 d.f., p < 0.01). These findings, if supported by future research, indicate a need to reassess policies regarding HCV infection.

Administration, Intranasal↗

PubMed2003

Recruitment of heterosexual couples in public health research: a study protocol.

BACKGROUND: Public health research involving social or kin groups (such as sexual partners or family members), rather than samples of unrelated individuals, has become more widespread in response to social ecological approaches to disease treatment and prevention. This approach requires the development of innovative sampling, recruitment and screening methodologies tailored to the study of related individuals. METHODS: In this paper, we describe a set of sampling, recruitment and screening protocols developed to enlist urban, drug-using, heterosexual couples into a public health research study. This population is especially hard to reach because they are engaged in illegal and/or stigmatized behaviors. The protocols were designed to integrate adaptive sampling, street- and referral-based recruitment, and screening procedures to verify study eligibility and relationship status. DISCUSSION: Recruitment of heterosexual couples through one partner, preferably the female, can be an effective enlistment technique. Verification of relationship status is an important component of dyadic research. Comparison of parallel questionnaires administered to each member of a dyad can aid in the assessment of relationship status. However, multiple independent sources of information should be used to verify relationship status when available. Adaptive sampling techniques were effective in reaching drug-using heterosexual couples in an urban setting, and the application of these methods to other groups of related individuals in clinical and public health research may prove to be useful. However, care must be taken to consider potential sources of sampling bias when interpreting and generalizing study results.

Adult↗

PubMed2003

Women's drug injection practices in East Harlem: an event analysis in a high-risk community.

This study described the most recent injection events of injection-drug-using women, determined the prevalence of HIV, hepatitis B (HBV), and hepatitis C (HCV), and identified significant predictors of injection-related risk behaviors. After validation of drug use, 185 street-recruited women participated in structured interviews and were offered HIV, HBV, and HCV testing and counseling. Interview topics included (1) demographic characteristics, (2) characteristics of injection partners (IPs), and (3) relevant situation-specific factors. Prevalence was 28% for HIV infection, 80% for HBV, and 70% for HCV. Injection events were either solitary (n = 110) or social (n = 75). Most were safe, and 75% of syringes used were obtained from a syringe exchange. Inferential analyses identified two variables that independently predicted unsafe events: (1) respondent had injected previously with her IP, and (2) her IP was her spouse or primary heterosexual partner. Two trends were identified: Injection events in which women felt "very close" to their IP or reported lack of control over injection practices tended to be unsafe. Although most events were safe, safe practices were not adhered to with spouses or primary partners. Syringe exchanges should be supported and may be an ideal setting for interventions targeted to drug-injecting couples.

Adult↗

PubMedDate not supplied

A potential hidden source of hepatitis C infection among noninjecting drug users.

Hepatitis C virus (HCV) is a major cause of chronic liver disease in the United States and worldwide. It is primarily transmitted through blood-to-blood contact with an infected individual. HCV is hyperendemic among injection drug users (IDUs), who contract the virus through contaminated syringes and drug preparation equipment shared with other IDUs. The prevalence of HCV is also high, to a lesser degree, among noninjection drug users, many of whom report no identifiable HCV risk exposures. This article reviews the epidemiological and virological evidence bearing on a potential hidden source of HCV infection among noninjection drug users: namely, the oral or intranasal transmission of HCV through the sharing of noninjection drug-use implements such as pipes or straws. While there is some epidemiological evidence supporting both oral and intranasal HCV transmission, most studies are hampered by methodological limitations. Thus, there is a need for prospective studies designed specifically to examine these potential routes of transmission. Current biological evidence does not refute either oral or intranasal transmission as possible sources of HCV infection, although more research is needed in the areas of oronasal HCV pathogenesis and the detection of HCV RNA in the nasal mucosa of intranasal drug users.

Administration, Intranasal↗