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Dive into the research topics where Alexis N. Martinez is active.

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Featured researches published by Alexis N. Martinez.


Journal of Urban Health-bulletin of The New York Academy of Medicine | 2010

Comparing Respondent-Driven Sampling and Targeted Sampling Methods of Recruiting Injection Drug Users in San Francisco

Alex H. Kral; Mohsen Malekinejad; Jason Vaudrey; Alexis N. Martinez; Jennifer Lorvick; Willi McFarland; H. Fisher Raymond

The objective of this article is to compare demographic characteristics, risk behaviors, and service utilization among injection drug users (IDUs) recruited from two separate studies in San Francisco in 2005, one which used targeted sampling (TS) and the other which used respondent-driven sampling (RDS). IDUs were recruited using TS (n = 651) and RDS (n = 534) and participated in quantitative interviews that included demographic characteristics, risk behaviors, and service utilization. Prevalence estimates and 95% confidence intervals (CIs) were calculated to assess whether there were differences in these variables by sampling method. There was overlap in 95% CIs for all demographic variables except African American race (TS: 45%, 53%; RDS: 29%, 44%). Maps showed that the proportion of IDUs distributed across zip codes were similar for the TS and RDS sample, with the exception of a single zip code that was more represented in the TS sample. This zip code includes an isolated, predominantly African American neighborhood where only the TS study had a field site. Risk behavior estimates were similar for both TS and RDS samples, although self-reported hepatitis C infection was lower in the RDS sample. In terms of service utilization, more IDUs in the RDS sample reported no recent use of drug treatment and syringe exchange program services. Our study suggests that perhaps a hybrid sampling plan is best suited for recruiting IDUs in San Francisco, whereby the more intensive ethnographic and secondary analysis components of TS would aid in the planning of seed placement and field locations for RDS.


Journal of Urban Health-bulletin of The New York Academy of Medicine | 2006

Sexual and Injection Risk among Women who Inject Methamphetamine in San Francisco

Jennifer Lorvick; Alexis N. Martinez; Lauren Gee; Alex H. Kral

Methamphetamine (MA) use is on the rise in the United States, with many cities reporting increases of 100% or more in MA-related Emergency Department (ED) mentions. Women are keeping pace with this trend: in 2003, 40% of ED mentions and 45% of MA-related treatment admissions were female. Although there have been extensive examinations of MA use and HIV/STI risk among gay men in recent years, literature regarding female MA users is scarce. This paper examines female methamphetamine injectors in San Francisco, CA, from 2003–2005. We assessed sexual and injection related risk behaviors, comparing female MA injectors to female injectors of other drugs. We also examined whether MA use was independently associated with specific sexual and injection risk behaviors. We found that female MA injectors were significantly more likely than non-MA injectors to report unprotected anal intercourse, multiple sexual partners, receptive syringe sharing and sharing of syringes with more than one person in the past six months. In multivariate analysis, MA use among female injectors was significantly associated with anal sex, more than five sexual partners, receptive syringe sharing, and more than one syringe-sharing partner in the past six months. Deeper exploration of the relationship between MA use and sexual risk among women would benefit HIV/STI prevention efforts. In addition, existing interventions for drug-injecting women may need to be adapted to better meet the risks of female MA injectors.


Journal of Urban Health-bulletin of The New York Academy of Medicine | 2005

HIV prevalence and risk behaviors among men who have sex with men and inject drugs in San Francisco

Alex H. Kral; Jennifer Lorvick; Daniel Ciccarone; Lynn Wenger; Lauren Gee; Alexis N. Martinez; Brian R. Edlin

The dual risks of male-to-male sex and drug injection have put men who have sex with men and inject drugs (MSM-IDU) at the forefront of the HIV epidemic, with the highest rates of infection among any risk group in the United States. This study analyzes data collected from 357 MSM-IDU in San Francisco between 1998 and 2002 to examine how risk behaviors differ by HIV serostatus and self-identified sexual orientation and to assess medical and social service utilization among HIV-positive MSM-IDU. Twenty-eight percent of the sample tested HIV antibody positive. There was little difference in risk behaviors between HIV-negative and HIV-positive MSM-IDU. Thirty percent of HIV-positive MSM-IDU reported distributive syringe sharing, compared to 40% of HIV negatives. Among MSM-IDU who reported anal intercourse in past 6 months, 70% of positives and 66% of HIV negatives reported unprotected anal intercourse. HIV status varied greatly by self-identified sexual orientation: 46% among gay, 24% among bisexual, and 14% among heterosexual MSM-IDU. Heterosexual MSM-IDU were more likely than other MSM-IDU to be homeless and to trade sex for money or drugs. Gay MSM-IDU were more likely to have anal intercourse. Bisexual MSM-IDU were as likely as heterosexual MSM-IDU to have sex with women and as likely as gay-identified MSM-IDU to have anal intercourse. Among MSM-IDU who were HIV positive, 15% were currently on antiretroviral therapy and 18% were currently in drug treatment, and 87% reported using a syringe exchange program in the past 6 months. These findings have implications for the development of HIV interventions that target the diverse MSM-IDU population.


PLOS Medicine | 2006

Reinterpreting Ethnic Patterns among White and African American Men Who Inject Heroin: A Social Science of Medicine Approach

Philippe Bourgois; Alexis N. Martinez; Alex H. Kral; Brian R. Edlin; Jeff Schonberg; Daniel Ciccarone

Background Street-based heroin injectors represent an especially vulnerable population group subject to negative health outcomes and social stigma. Effective clinical treatment and public health intervention for this population requires an understanding of their cultural environment and experiences. Social science theory and methods offer tools to understand the reasons for economic and ethnic disparities that cause individual suffering and stress at the institutional level. Methods and Findings We used a cross-methodological approach that incorporated quantitative, clinical, and ethnographic data collected by two contemporaneous long-term San Francisco studies, one epidemiological and one ethnographic, to explore the impact of ethnicity on street-based heroin-injecting men 45 years of age or older who were self-identified as either African American or white. We triangulated our ethnographic findings by statistically examining 14 relevant epidemiological variables stratified by median age and ethnicity. We observed significant differences in social practices between self-identified African Americans and whites in our ethnographic social network sample with respect to patterns of (1) drug consumption; (2) income generation; (3) social and institutional relationships; and (4) personal health and hygiene. African Americans and whites tended to experience different structural relationships to their shared condition of addiction and poverty. Specifically, this generation of San Francisco injectors grew up as the children of poor rural to urban immigrants in an era (the late 1960s through 1970s) when industrial jobs disappeared and heroin became fashionable. This was also when violent segregated inner city youth gangs proliferated and the federal government initiated its “War on Drugs.” African Americans had earlier and more negative contact with law enforcement but maintained long-term ties with their extended families. Most of the whites were expelled from their families when they began engaging in drug-related crime. These historical-structural conditions generated distinct presentations of self. Whites styled themselves as outcasts, defeated by addiction. They professed to be injecting heroin to stave off “dopesickness” rather than to seek pleasure. African Americans, in contrast, cast their physical addiction as an oppositional pursuit of autonomy and pleasure. They considered themselves to be professional outlaws and rejected any appearance of abjection. Many, but not all, of these ethnographic findings were corroborated by our epidemiological data, highlighting the variability of behaviors within ethnic categories. Conclusions Bringing quantitative and qualitative methodologies and perspectives into a collaborative dialog among cross-disciplinary researchers highlights the fact that clinical practice must go beyond simple racial or cultural categories. A clinical social science approach provides insights into how sociocultural processes are mediated by historically rooted and institutionally enforced power relations. Recognizing the logical underpinnings of ethnically specific behavioral patterns of street-based injectors is the foundation for cultural competence and for successful clinical relationships. It reduces the risk of suboptimal medical care for an exceptionally vulnerable and challenging patient population. Social science approaches can also help explain larger-scale patterns of health disparities; inform new approaches to structural and institutional-level public health initiatives; and enable clinicians to take more leadership in changing public policies that have negative health consequences.


International Journal of Drug Policy | 2014

Activity spaces among injection drug users in San Francisco

Alexis N. Martinez; Jennifer Lorvick; Alex H. Kral

BACKGROUND Representations of activity spaces, defined as the local areas within which people move or travel in the course of their daily activities, are unexplored among injection drug users (IDUs). The purpose of this paper is to use an activity space framework to study place and drug user health. METHODS Data for this analysis is from an epidemiological study of street-recruited IDUs in San Francisco (N=1084). Study participants reported geographic intersections of where they most often slept at night, hung out during the day, and used drugs during a 6 month time period. We used GIS software to construct and map activity space routes of street-based network paths between these intersections. We further identified if syringe exchange program (SEP) locations intersected with, participant activity space routes. We used logistic regression to estimate associations between activity space variables and HIV serostatus, syringe sharing, and non-fatal overdose, after adjusting for individual and Census tract covariates. RESULTS Mean activity space distance for all participants was 1.5miles. 9.6% of participants had a SEP located along their activity space. An increase in activity space distance was associated with a decrease in odds of being HIV positive. An increase in residential transience, or the number of different locations slept in by participants in a 6 month time period, was associated with higher odds of syringe sharing. Activity space distance was not independently associated with overdose or syringe sharing. DISCUSSION Research that locates individuals in places of perceived importance is needed to inform placement and accessibility of HIV and overdose prevention programs. More attention needs to be given to the logistics of collecting sensitive geospatial data from vulnerable populations as well as how to maximize the use of GIS software for visualizing and understanding how IDUs interact with their environment.


International Journal of Environmental Research and Public Health | 2014

Spatial Analysis of HIV Positive Injection Drug Users in San Francisco, 1987 to 2005

Alexis N. Martinez; Lee R. Mobley; Jennifer Lorvick; Scott P. Novak; Andrea M. Lopez; Alex H. Kral

Spatial analyses of HIV/AIDS related outcomes are growing in popularity as a tool to understand geographic changes in the epidemic and inform the effectiveness of community-based prevention and treatment programs. The Urban Health Study was a serial, cross-sectional epidemiological study of injection drug users (IDUs) in San Francisco between 1987 and 2005 (N = 29,914). HIV testing was conducted for every participant. Participant residence was geocoded to the level of the United States Census tract for every observation in dataset. Local indicator of spatial autocorrelation (LISA) tests were used to identify univariate and bivariate Census tract clusters of HIV positive IDUs in two time periods. We further compared three tract level characteristics (% poverty, % African Americans, and % unemployment) across areas of clustered and non-clustered tracts. We identified significant spatial clustering of high numbers of HIV positive IDUs in the early period (1987–1995) and late period (1996–2005). We found significant bivariate clusters of Census tracts where HIV positive IDUs and tract level poverty were above average compared to the surrounding areas. Our data suggest that poverty, rather than race, was an important neighborhood characteristic associated with the spatial distribution of HIV in SF and its spatial diffusion over time.


American Journal of Public Health | 2011

Syringe Disposal Among Injection Drug Users in San Francisco

Lynn Wenger; Alexis N. Martinez; Lisa Carpenter; Dara Geckeler; Grant Colfax; Alex H. Kral

To assess the prevalence of improperly discarded syringes and to examine syringe disposal practices of injection drug users (IDUs) in San Francisco, we visually inspected 1000 random city blocks and conducted a survey of 602 IDUs. We found 20 syringes on the streets we inspected. IDUs reported disposing of 13% of syringes improperly. In multivariate analysis, obtaining syringes from syringe exchange programs was found to be protective against improper disposal, and injecting in public places was predictive of improper disposal. Few syringes posed a public health threat.


Substance Use & Misuse | 2011

HIV prevalence and risk among heterosexual methamphetamine injectors in California

Alex H. Kral; Jennifer Lorvick; Alexis N. Martinez; Megan A. Lewis; W. Alexander Orr; Rachel Anderson; Neil M. Flynn; Ricky N. Bluthenthal

This study funded by Centers for Disease Control compares HIV prevalence and risk behavior among heterosexual methamphetamine (n = 428) and nonmethamphetamine (n = 878) injectors in California, USA, during 2001–2003. While HIV was not highly prevalent among methamphetamine injectors (3%), sexual and injection risk behaviors were highly prevalent (ranging from 21% to 72%). In multivariate analyses, methamphetamine injectors had higher odds than nonmethamphetamine injectors of unprotected vaginal intercourse and sex with five or more sexual partners in the past 6 months and of distributive and receptive syringe sharing in the past 30 days. There was no significant difference in HIV sero-status by methamphetamine use. Suggestions are made for designing HIV prevention programs. The studys limitations are noted.


Journal of Urban Health-bulletin of The New York Academy of Medicine | 2010

Non-prescription Syringe Sales in California: A Qualitative Examination of Practices among 12 Local Health Jurisdictions

Valerie J. Rose; Glenn Backes; Alexis N. Martinez; Willi McFarland

Legislation permitting non-prescription syringe sales (NPSS) was passed in 2004 in California as a structural intervention designed to expand access to syringes for injection drug users. As of December 2009, 19 of California’s 61 local health jurisdictions (LHJs) have approved policies to authorize pharmacies to sell non-prescription syringes. The legislation faces termination in 2010 if current evaluation efforts fail to demonstrate outcomes defined in the legislation. Using qualitative methods, we examined the systems and procedures associated with implementation; identified facilitators and barriers to implementation among 12 LHJs, and documented the role of public health in initiating and sustaining local programs. We identified consistent activities that led to policy implementation among LHJs and discovered several barriers that were associated with failure to implement local programs. Factors leading to NPSS were public health leadership; an inclusive planning process, marketing the program as a public health initiative; learning from others’ efforts, successes, and failures; and identifying acceptable syringe disposal options in advance of program implementation. Health departments that were confronted with political and moral arguments lost momentum and ultimately assigned a lower priority to the initiative citing the loss of powerful public health advocates or a lack of human resources. Additional barriers were law enforcement, elected officials, and pharmacy opposition, and failure to resolve syringe disposal options to the satisfaction of important stakeholders. The lessons learned in this study should provide useful guidance for the remaining LHJs in California without NPSS programs.


Journal of Drug Issues | 2012

Nonmedical Prescription Drug Use Among Injection Drug Users

Alexis N. Martinez; Elizabeth J. D’Amico; Alex H. Kral; Ricky N. Bluthenthal

This study described the prevalence and risk factors for nonmedical prescription drug use (NMPD) among injection drug users (IDUs) recruited at syringe exchange programs (SEPs) in California. Interviews were conducted with 1,586 IDUs recruited from 24 SEPs across three annual cross-sections between 2001 and 2003. Any NMPD use in the past 6 months was reported by 17% of the sample. Factors independently associated with depressant use include recent participation in a drug treatment program, recent injection of heroin, and frequency of injection. Factors independently associated with opioid use include frequency of injection and history of incarceration. NMPD depressant use increased the odds of a nonfatal overdose in the past year. The authors’ findings represent a first step toward creating an epidemiologic profile of NMPD use that may be useful for targeting the implementation of interventions that are effective in reducing overdoses, a significant cause of mortality among IDUs worldwide.

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Ricky N. Bluthenthal

University of Southern California

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Neil M. Flynn

University of California

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Brian Karl Finch

San Diego State University

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