R R Robles

University of Puerto Rico, Medical Sciences Campus, San Juan, San Juan, Puerto Rico

Are you R R Robles?

Claim your profile

Publications (38)74.8 Total impact

  • Source
    [show abstract] [hide abstract]
    ABSTRACT: During the last decade, the veterinary anesthetics have gained popularity as recreational drugs. The aim of this study was to document the use of "anestecia de caballo" (xylazine) and its consequences among drug users in Puerto Rico. The study combined a cross-sectional survey with 89 drug users and two focus groups conducted in Mayagüez with frontline drug treatment providers. Drug users were recruited from communities of the San Juan metropolitan area using a variety of ethnographic and outreach strategies. A short questionnaire developed for the study collected information on sociodemographics, xylazine use, and its consequences. The two focus groups were conducted to discuss the details related to xylazine use, its consequences, and utilization awareness. The sample comprised 63 males (70.8%) and 26 females with a mean age of 37.2 years. The mean number of years of drug use was 14.3, with a mean frequency of drug use of 5.9 times daily. More than 65% reported speedball as the principal drug of use. The prevalence of xylazine use was 80.7%. More than 42% of the sample used xylazine in a mixture with speedball. The main route of administration of xylazine was injection but 14% reported the use of xylazine by inhalation. More than 35% of the sample reported skin lesions and 21.1% reported at least one overdose episode. Multiple logistic regression analysis revealed that males (OR = 3.47, CI = 1.10-12.00) and those who reported speedball as their main drug of use (OR = 9.34, CI = 2.51-34.70) were significantly more likely to be xylazine users. Focus groups revealed that drug users claimed to recognize the presence of xylaxine in a mixture of speedball based on its effects, taste, the color of the drug (dark brown), and its odor. In conclusion, the use of xylazine among drug users in Puerto Rico seems to be an emerging trend with potentially serious health consequences.
    Journal of Urban Health 03/2012; 89(3):519-26. · 1.89 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Research suggests that sexual silence, family loyalty, and homophobia foster health-compromising behaviors among adult Latino gay males, but little is known about the effect of these sociocultural factors on the lives of Latino children and young teens characterized by gender nonconformity and homosexual orientation. This exploratory study of Puerto Rican men who have sex with men (MSM) used multisession qualitative interviews to examine early life experiences related to gender identity and homosexual orientation, and the place of drug use and risky sexual behavior in sexual identity formation. Gay male and transsexual female participants described at least one sympathetic family member, usually a female, who accepted cross-gender behavior and/or homosexual orientation. Half of the participants experienced unwanted sex as minors, and all were subjected to bullying by schoolmates. As pubescent youth, participants frequented adult gay venues where they were exposed to high-risk sexual and drug-related behaviors. Interventions for sexually questioning and gay/transsexual Puerto Rican youth are proposed.
    Youth &amp Society 01/2007; 39(3):362-384. · 1.82 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: Throughout the world, injection drug users (IDUs) are the group at highest risk for hepatitis C virus (HCV) infection. IDUs residing in the island of Puerto Rico and Puerto Rican IDUs residing in the U.S. mainland have been shown to be at very high risk of infection with HIV. However, the extent to which HCV infection has spread among IDUs in Puerto Rico is not yet known. The aims of this study were to estimate seroprevalence of HCV and to identify the correlates associated with HCV transmission. The sample was drawn through street outreach strategies and was comprised of 400 injection drug users not in treatment, living in the San Juan metropolitan area. HCV and HIV infection were detected by enzyme-linked immunosorbent assay and the results were confirmed by Western blot. Information on sociodemographics, drug use patterns, and risk behaviors was obtained through structured interviews. Bivariate analyses and multivariate logistic regression were used to assess covariates of infection with HCV. The prevalence of HCV infection was 89%. After controlling for sociodemographic characteristics, HCV infection was positively associated with increasing years of injection, injecting in a shooting gallery, tattooing in prison, and self-reported STD infection. Notably, IDUs who had initiated drug injection within the year prior to the study interview had an HCV infection rate of 57%. This study indicates that more aggressive educational programs are urgently needed to reduce the spread of HCV infection among IDUs in Puerto Rico.
    Journal of Urban Health 12/2006; 83(6):1105-13. · 1.89 Impact Factor
  • Source
    H M Colón, R R Robles, H Sahai
    [show abstract] [hide abstract]
    ABSTRACT: Despite the widespread use of household surveys to assess the epidemiology of illicit drug use and abuse, there is very little information about the willingness of respondents to disclose their use of drugs in household studies outside the US. As part of a household study of substance use disorders in Puerto Rico, we collected hair specimens from a sub-sample of 114 respondents. Hair specimens were screened using a radio immunoassay. Screened-positive specimens were confirmed using gas chromatography/mass spectrometry. Using hair-test results as the standard, specificity of self-reports was 98% or higher for both drugs. The sensitivity of all self-reports was low, although lifetime use reports had somewhat higher sensitivities. The sensitivity of self-reports of recent cocaine use was particularly low, 7.1%. The sensitivity of heroin use reports was somewhat higher, 33.3% for recent use and 66.7% for lifetime use. The estimate of recent cocaine use based on hair tests was 13.7 times the estimate generated from interview reports. For heroin use, the test-based estimate was 2.9 times the rate generated from the interview reports. A shift from the cut-off level of 0.2 ng/mg to 0.5 ng/mg had only a marginal improvement on validity, with sensitivity increasing from 7.1% to 11.1% for self-reported recent cocaine use. The results suggest that drug users, for the most part, are not willing to disclose their use of drugs in household surveys in Puerto Rico. Methods to increase the willingness of respondents to disclose their use of drugs are needed.
    International Journal of Epidemiology 11/2001; 30(5):1042-9. · 6.98 Impact Factor
  • H M Colón, R R Robles, G Canino, H Sahai
    [show abstract] [hide abstract]
    ABSTRACT: We report the basic findings of a survey aimed at estimating rates of substance disorders in a probability sample of 4,709 household residents aged 15 to 64 years old. Lifetime use of alcohol was reported by 77.2%, and 10.7% reported ever using illicit drugs. Overall, 14.7% of the sample met criteria for a lifetime substance disorder, and 4.9% for a past year disorder. The rates of lifetime disorders were 13.1% for alcohol and 4.1% for illicit drug. Past year abuse/dependence was 4.3% for alcohol and 1.3% for illicit drugs. Alcohol use disorders were associated with male gender, higher family annual income, being employed, and being married. Illicit drug use disorders were associated with male gender and younger age. Only 13.0% of respondents with a past year disorder reported using services for their disorder. A program of continuous monitoring of substance using disorders is critical to establishing and monitoring effective policies.
    Boletín de la Asociación Médica de Puerto Rico 01/2001; 93(1-12):12-22.
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: This study assessed prevalence and correlates of anergy among a cohort of drug users in communities in the San Juan metropolitan area. In all, 719 drug injectors and crack users were recruited in neighbourhoods in the San Juan metropolitan area following a stratified cluster design of 30 copping areas (places where drugs are sold). Slightly more than one-third of the total proportion of participants, 34.2%, were HIV positive and 30.3% anergic. Subjects with a history of incarceration, the HIV positive, and those reporting chronic illness were more likely to be anergic than those subjects without these characteristics. Most studies addressing drug users' immune system dysfunction are related to HIV infection. Additional studies are needed to provide a more comprehensive understanding of drug users' immune systems.
    International Journal of Epidemiology 07/1999; 28(3):509-13. · 6.98 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: This study evaluated the effectiveness of the first needle exchange program (NEP) established in Puerto Rico. The data for this study were collected during the first months of the NEP from July 1995 to March 1996 in 13 communities of the San Juan metropolitan area. Subjects were the participants of two modalities of the NEP: a mobile team and a community-based drug treatment program. During the 3-week evaluation period, 2401 injection drug users (IDUs) were recruited, resulting in a total of 19,195 exchange contacts and 146,323 syringes exchanged. No significant change in drug injection was observed. However, the program was effective in reducing sharing of syringes and cookers. The study suggests that the NEP did help in reducing needle sharing in Puerto Rico. However, the HIV seropositivity in returned syringes suggests the need to continue aggressive prevention programs to arrest the epidemic among IDUs. However, factors related to the socio-cultural environment as well as cultural norms and traditions need to be considered when planning and expanding NEPs.
    Health Policy 10/1998; 45(3):209-20. · 1.55 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: This study examines the effects of health, predisposing, and enabling factors on recognition of a mental health problem, use of formal mental health care, and contact with a specialized mental health provider. Interviews were conducted with a probability sample of 3,435 adults. The variables examined include measures of mental health; social and demographic factors; and enabling factors relevant to the help-seeking process. Subjective and objective measures of mental health were associated with the recognition of a mental health problem. The objective assessment of definite need for services was relevant for the use of formal services. However, the subjects' perception of poor mental health was strongly related to receiving care from a mental health specialist. Although interaction with social networks is associated with use of formal services, low economic strain is related to receiving care from the specialty sector. The results support the importance of using multiple measures of mental health problems. The finding that individuals' perceived economic strain increases the likelihood of receiving specialized care suggests that studies of economic barriers to the use of mental health services might benefit from the adoption of measures that assess perceived economic circumstances.
    Medical Care 08/1998; 36(7):1047-56. · 3.23 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Despite available strategies to prevent sex risk behaviours in Puerto Rico, heterosexual transmission of HIV continues to increase. Since 1990, heterosexual contact has been the fastest growing infection risk category among the island's general population, and the primary transmission route for women and children. To understand change in sex risk behaviours and factors related to change, 911 drug injectors and 359 crack smokers were recruited from the San Juan metropolitan area following a stratified cluster design. This study comprised a total of 1,004 (79.1%) drug users who were assessed at follow-up. Abstinence from sex behaviour increased from 54.6% to 61.1% (p < 0.01), use of condoms during vaginal sex also increased from 26.4% to 36.9% (p < 0.01). In multivariate analysis, significant predictors of abstinence were gender, injection drug use, HIV seropositivity and not having a steady partner. Predictors of using condoms during vaginal sex were HIV seropositivity, STD diagnosis and participation in an HIV preventive programme. These findings indicate that additional HIV preventive efforts are needed to reduce sex risk behaviours among drug users who have a steady sex partner, as well as among drug users who are HIV-negative.
    AIDS Care 07/1998; 10(3):329-38. · 1.60 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: This study was designed to assess HIV risk behaviors, HIV seroprevalence, and tuberculosis (TB) infection in shooting gallery managers in Puerto Rico. The subjects were 464 injection drug users (IDUs), of whom 12.5% reported managing shooting galleries. The median frequency of drug injection was higher in shooting gallery managers than in nonmanagers. A trend was observed for purified protein derivative (PPD) reactivity to increase according to the length of time spent as a gallery manager, but this trend was not statistically significant. However, anergy rates increased significantly with increase in the number of months spent as shooting gallery manager (p = .021). Multivariate analyses showed that IDUs reporting shooting gallery management experience of > or = 25 months were more likely to be infected with HIV. Prevention programs need to emphasize strategies to protect the health of shooting gallery clients and, in particular, shooting gallery managers. Additional studies are required to determine effective strategies for reducing the risk of HIV and TB infection in shooting galleries.
    Journal of Acquired Immune Deficiency Syndromes and Human Retrovirology 04/1998; 17(5):477-83.
  • [show abstract] [hide abstract]
    ABSTRACT: Activation of CD4+ cells is a prerequisite for infection by the human immunodeficiency virus (HIV). Thus, any agent capable of suppressing CD4+ cell proliferation could create a refractory stage that would impede viral infection. We have reported, in a previous publication, that a biological response modifier (BRM), polyantigenic immunomodulator (PAI) substantially reduces HIV-1 titer (from 20 to 100%) in peripheral mononuclear cells (PBMC) cultures with high viral titer (p24 = 10(2)-10(5) pg/ml). We are presenting data suggesting that the reported reduction in virus titer seems to be associated with a suppressive activity of PAI on the proliferation of PBMC from intravenous drug users (IVDU) infected and non-infected with HIV-1. PAI, a well characterized BRM, is a mixture of inactivated bacterial and influenza virus vaccines. PBMC from healthy donors and IVDU individuals were exposed to PAI, phytohemagglutinin (PHA), interleukin-2 (IL-2) and to combinations of PAI with either PHA or IL-2. Appropriate controls were included. 3H-thymidine pulsing was used as indicator of cell proliferation. The stimulation index and the difference between mean cpm of test sample and control were used to measure proliferative activity. There was a low proliferative response in the PBMC cultures from IVDU and HIV-1 positive patients, but it was substantially lower in the later group. When PBMC cultures from the same group of individuals were exposed to PAI, PHA and IL-2, and to the combination of either PAI plus PHA or IL-2, the response observed in the PAI treated group was uniformly lower than in the other treated cultures. Moreover, when PAI was combined with PHA, it exerted a significant reduction in the measured parameters. The effect of PAI on IL-2 activity was negligible. A suppressive effect of a PAI has been detected on the proliferation of PBMC from IVDA and HIV-1 positive individuals. This activity may be associated with the capacity of PAI to reduce HIV titers in infected PBMC cultures.
    Cellular and molecular biology 12/1997; 43(7):981-8. · 0.81 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Identify risk factors associated to violent behavior among adolescent students. A survey was conducted using a two-staged stratified cluster sampling design. It represents all junior and high school students of Puerto Rico. Students from 117 schools were administered an anonymous questionnaire. Alcohol use was reported by 78.7% of students, and 14% reported illegal drug use. About 25% committed one violent act during the previous year, and 22% committed two acts or more. Drug use, alcohol use, not getting along with their parents, being a male, school failure and drug use by siblings were identified as risk factors for violent behavior. Church attendance was identified as a protective factor. Primary physicians can play an important role in violence prevention through early identification of family violence.
    Boletín de la Asociación Médica de Puerto Rico 01/1997; 89(7-9):146-9.
  • [show abstract] [hide abstract]
    ABSTRACT: To examine the influence of knowledge of HIV serostatus on changes in risk behaviors among injecting drug users (IDU). IDU were recruited through sampling conducted at street drug-selling areas. Of 374 participants, 88.8% consented to be HIV tested and returned for their test results, and 73.5% were relocated and interviewed 6 months later. Of the 176 IDU who reported a seronegative test result prior to baseline, 29 tested seropositive at baseline. No significant differences were found between HIV-positive and HIV-negative IDU in needle risk behaviors. HIV-positive IDU were significantly less likely to report being sexually active [odds ratio (OR), 0.41 : 95% confidence interval (CI), 0.22-0.75] and more likely to use condoms during vaginal (OR, 4.43; 95% CI, 1.48-13.29) and oral sex (OR, 6.67; 95% CI, 1.42-31.33). The findings of this study show the importance of encouraging IDU to undergo periodic retesting. HIV testing could have an important role in reducing heterosexual transmission from IDU.
    AIDS 10/1996; 10(10):1163-8. · 6.41 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: This study examines the prevalence of crack use among out-of-treatment drug users in the San Juan metropolitan area. Of the sample of 849 drug users, 310 (36.5%) were crack users only, 179 (21.1%) were drug injectors and crack users, and 360 (42.4%) were drug injectors only. To study the characteristics of crack users we selected the subjects who reported the use of crack only. Of the 310 subjects, 193 (62.3%) men and 117 (37.7%) women, the mean age was 29 years. Significant differences were observed by gender. Females reported higher education, living in a nuclear family, crack/cocaine as the first drug used, history of sexually transmitted diseases and higher rates of HIV seropositivity. Males were more likely to report income from illegal activities, incarceration, use of multiple drugs, and more years of drug use. Among those sexually active, females were more likely to practice unprotected vaginal sex, have multiple sex partners, engage in prostitution (exchange of sex for money and/or drugs) and use condoms.
    Puerto Rico health sciences journal 10/1996; 15(3):221-5. · 0.71 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Needle sharing is one of the principal risk behaviors leading to HIV transmission among injection drug users (IDUs). Shooting galleries, a social context where IDUs rent, share, and borrow needles, are locations usually found near drug markets. This study, which interviewed 1,700 IDUs from May 1989 to June 1990, assesses sociodemographic characteristics and HIV risk behaviors among shooting gallery users in Puerto Rico. Multivariate analyses showed that shooting gallery use is associated with speedball (a concoction of heroin and cocaine) injection, income from illegal activities and previous drug treatment. Shooting gallery users were more likely to rent, share, and borrow needles, and less likely to always use bleach and water to clean needles. Strategies to reduce shooting gallery use among drug injectors are discussed.
    Puerto Rico health sciences journal 10/1996; 15(3):227-31. · 0.71 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: This study aims to determine the prevalence of Mycobacterium tuberculosis infection and its association with HIV and other health risk factors among drug users. A sample of 716 IDUs and crack users were enrolled from community sites. Consenting subjects were tested for HIV serum antibody status. Drug users with an unknown PPD status were administered a PPD skin test and an anergy panel of three antigens (Candida, mumps and tetanus). Overall, 68 (10.3%) were reactive to the PPD skin test, 240 (34.7%) were HIV positive and 195 (29.5%) showed cutaneous anergy. Participants infected with tuberculosis (TB) were more likely to be HIV seropositive, and to have a history of incarceration and residential drug treatment than those not infected. In addition, TB infection was more prevalent among intravenous drug users (IDUs) and shooting gallery managers. These findings suggest that drug users should be considered at high risk for TB and HIV infection. Innovative programs to monitor both infections among drug users are needed to arrest what can become a dual epidemic of HIV and TB in the near future.
    Puerto Rico health sciences journal 10/1996; 15(3):233-6. · 0.71 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: This study evaluates the protective effect on risk behaviors of an HIV testing and counseling program among two groups of drug abusers: African Americans in the U.S. (981) and Puerto Ricans in Puerto Rico and the U.S. (144). Among African Americans, injection risk behaviors at follow-up were independent of the type of HIV test result received. In the case of Puerto Ricans, those receiving a seropositive result were more likely to report shared use of cookers. Among seropositive African Americans and Puerto Ricans a significant risk reduction occurred in sexual risk behavior. Seropositives were less likely to persist in practicing unprotected vaginal sex. Seropositive African Americans were also less likely to persist in practicing unprotected oral sex. Future analyses will need to identify the circumstances under which seropositive individuals continue or discontinue harm behaviors.
    Drugs & Society 02/1996; 9(1-2):173-84.
  • [show abstract] [hide abstract]
    ABSTRACT: The relationship between perceived risk of developing AIDS and subsequent behavioral risk status is estimated for 1740 Puerto Rican injection drug users (IDUs). Prospective behavioral effects were examined comparing data collected at two intervals approximately 6 months apart. We estimated the association between perceived risk at baseline and risky behaviors at follow-up with unadjusted odds ratios. We confirmed the results with adjusted odds ratios using logistic regressions which included baseline risk status as well as socio-demographic and health status covariates. The analyses showed that having a high HIV/AIDS risk perception was related to subsequent sharing of needles, injection of drugs in shooting galleries and sharing of cookers. None of the tests between risk perception and sex risk behaviors showed a significance association. Increasing IDUs' perceived vulnerability to HIV/AIDS might not be effective in helping reduce HIV risk behaviors. IDUs perceiving themselves to be at high risk of AIDS might believe there is little they can do to reverse the consequences of risky behavior.
    Addiction 09/1995; 90(8):1105-11. · 4.58 Impact Factor
  • H M Colón, H Sahai, R R Robles, T D Matos
    [show abstract] [hide abstract]
    ABSTRACT: This report assesses the effects of a community outreach program in reducing HIV risk behaviors among injection drug users (IDUs) in San Juan, Puerto Rico. Participants were 1,113 IDUs, 88.3% of whom were also assessed at post-intervention. The analytic strategy consisted in modeling pre- and post-intervention trends in risk behavior levels from successive cohorts of IDUs. The trend analyses showed that secular trends, unrelated to the direct effects of the outreach intervention, accounted for significant portions of the reported risk reductions. Nevertheless, the post-intervention trends in the shared use of cookers and in needle bleaching showed shifts that could not be accounted for by the modeled secular trends. The outreach intervention appears to have had significant but partial effects on the behavioral risks associated to drug injection and no effect on sexual behaviors. The strengths and weaknesses of time-trend analyses for evaluating community HIV-prevention programs lacking experimental designs are discussed.
    AIDS Education and Prevention 07/1995; 7(3):195-209. · 1.59 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: This paper examines the association of depressive symptoms with human immunodeficiency virus (HIV) infection and risk behaviors among 127 sex workers. Data were obtained by a structured interview and blood specimens tested for HIV. Findings showed a high prevalence rate of depressive symptoms for all sex workers regardless of HIV infection status. Results of a logistic regression analysis indicated that the use of injected drugs and engaging in unprotected intercourse with clients were strongly associated with a high level of depressive symptoms.
    American Journal of Public Health 01/1995; 84(12):2000-2. · 3.93 Impact Factor

Publication Stats

390 Citations
74.80 Total Impact Points

Institutions

  • 2012
    • University of Puerto Rico, Medical Sciences Campus
      San Juan, San Juan, Puerto Rico
  • 1998–2012
    • Central University of the Caribbean
      • School of Medicine
      Bayamon, Cidra, Puerto Rico
  • 1991–1994
    • University of Puerto Rico at Rio Piedras
      San Juan, San Juan, Puerto Rico
  • 1993
    • Polytechnic University of Puerto Rico
      San Juan, San Juan, Puerto Rico