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Biomedical subjects

David Vlahov

Publications and source records attributed to David Vlahov.

At least 181 records · Page 10Linked to original sources
PubMed2002

High-risk behaviors associated with transition from illicit non-injection to injection drug use among adolescent and young adult drug users: a case-control study.

OBJECTIVE: The goal of our study was to elucidate characteristics of persons likely to transition into injection drug use so that an identifiable group with high-risk for blood-borne infection may be targeted for interventions. METHODS: An age-matched case-control analysis was performed from a cohort study in Baltimore, 1997-1999, of street-recruited non-injection and injection drug users (IDUs), aged 15-30. Cases were IDUs injecting < or = 2 years and controls were age-matched persons who used non-injection heroin, cocaine or crack. At baseline, all were interviewed about prior year-by-year behaviors; analysis using conditional logistic regression was based on information for the year prior to injection onset for the case and the same calendar time for the controls as well as recent behaviors for both groups. RESULTS: Of 270 participants, most were African American (78%), female (61%), and HIV seroprevalence was 7% at baseline. IDUs were significantly more likely than controls to be non-African American (adjusted odds ratio (AOR)=0.09) and report high school dropout (AOR=2.32), early sex-trading (AOR=2.72), and recent violence victimization (AOR=9.28). CONCLUSION: Given that new injectors are at high-risk for HIV and hepatitis yet difficult to reach for prevention efforts, our data suggest some categories to use to target non-injectors who are likely to transition into injection use.

Adolescent↗
PubMed2002

Psychological sequelae of the September 11 terrorist attacks in New York City.

BACKGROUND: The scope of the terrorist attacks of September 11, 2001, was unprecedented in the United States. We assessed the prevalence and correlates of acute post-traumatic stress disorder (PTSD) and depression among residents of Manhattan five to eight weeks after the attacks. METHODS: We used random-digit dialing to contact a representative sample of adults living south of 110th Street in Manhattan. Participants were asked about demographic characteristics, exposure to the events of September 11, and psychological symptoms after the attacks. RESULTS: Among 1008 adults interviewed, 7.5 percent reported symptoms consistent with a diagnosis of current PTSD related to the attacks, and 9.7 percent reported symptoms consistent with current depression (with "current" defined as occurring within the previous 30 days). Among respondents who lived south of Canal Street (i.e., near the World Trade Center), the prevalence of PTSD was 20.0 percent. Predictors of PTSD in a multivariate model were Hispanic ethnicity, two or more prior stressors, a panic attack during or shortly after the events, residence south of Canal Street, and loss of possessions due to the events. Predictors of depression were Hispanic ethnicity, two or more prior stressors, a panic attack, a low level of social support, the death of a friend or relative during the attacks, and loss of a job due to the attacks. CONCLUSIONS: There was a substantial burden of acute PTSD and depression in Manhattan after the September 11 attacks. Experiences involving exposure to the attacks were predictors of current PTSD, and losses as a result of the events were predictors of current depression. In the aftermath of terrorist attacks, there may be substantial psychological morbidity in the population.

Adult↗
PubMed2002

High prevalence of iron deficiency and anemia among female injection drug users with and without HIV infection.

INTRODUCTION: Anemia is associated with increased progression of disease and higher mortality during HIV infection. OBJECTIVE: To determine the prevalence of iron deficiency and iron deficiency anemia among female injection drug users (IDUs) with and without HIV infection. METHODS: Hemoglobin and plasma ferritin were measured in a cross-sectional study of a cohort of female IDUs followed in Baltimore, Maryland. RESULTS: Among 136 HIV-positive and 61 HIV-negative women, the prevalence of anemia was 44.1% and 26.2% ( p <.02), the prevalence of iron deficiency was 37.5% and 42.6% ( p =.49), and the prevalence of iron deficiency anemia was 20.6% and 14.7% ( p =.33), respectively. The overall prevalence of hepatitis C infection was 90.5%. Iron deficiency anemia accounted for 46.7% and 56.1% of the anemia among HIV-positive and HIV-negative female IDUs. CONCLUSIONS: Iron deficiency accounts for about half of the anemia among female IDUS. Although iron supplementation is indicated for anemia patients, such treatment should be approached with caution in women coinfected with HIV and hepatitis C virus, because iron supplementation and overload have been associated with increased progression of HIV infection, worsening of hepatitis C virus infection, and higher mortality.

Anemia, Iron-Deficiency↗
PubMed2002

Validity of self-reported needle exchange attendance among injection drug users: implications for program evaluation.

Some studies have indicated that needle exchange programs (NEPs) can be effective in reducing drug-related risks for human immunodeficiency virus (HIV) seroconversion; however, others have reported higher HIV incidence rates among NEP attendees. Since many studies rely on self-reports of NEP attendance, the authors investigated the extent to which differential misreporting of NEP attendance could bias risk estimates. Over a 3-year period from 1994 to 1997, self-reports of NEP attendance from participants in a prospective study in Baltimore, Maryland, were compared with NEP records. Of 1,315 participants, 459 (35%) had registered with the Baltimore NEP. There was 86.7% concordance between self-reported and actual NEP use; 11.0% reported NEP attendance but did not attend (overreported), and 2.2% reported not attending NEP but did attend (underreported). In multivariate analyses using generalized estimating equations, persons who overreported NEP attendance were more likely to have injected frequently (adjusted odds ratio (AOR) = 1.29, 95% confidence interval (CI): 1.04, 1.61), denied needle sharing (AOR = 0.69; 95% CI: 0.52, 0.89), and been an HIV seroconverter (AOR = 1.83, 95% CI: 1.11, 3.01). With Poisson regression to model predictors of HIV seroconversion, models that included measures of NEP attendance based on self-reports compared with actual program data underestimated a protective association by 18%. These findings have important implications for evaluations of NEPs.

Adult↗
PubMed2002

An investigation of the psychological effects of the September 11, 2001, attacks on New York City: developing and implementing research in the acute postdisaster period.

The September 11, 2001, attack on New York City was the largest human-made disaster in United States history. In the first few days after the attack, it became clear that the scope of the attacks (including loss of life, property damage, and financial strain) was unprecedented and that the attacks could result in substantial psychological sequelae in the city population. Researchers at the Center for Urban Epidemiologic Studies at the New York Academy of Medicine designed and implemented an assessment of the mental health of New Yorkers 5-8 weeks after the attacks. To implement this research in the immediate postdisaster period, researchers at the center had to develop, in a compressed time interval, new academic collaborations, links with potential funders, and unique safeguards for study respondents who may have been suffering from acute psychological distress. Results of the assessment contributed to a New York state mental health needs assessment that secured Federal Emergency Management Agency funding for mental health programs in New York City. This experience suggests that mechanisms should be in place for rapid implementation of mental health assessments after disasters.

Journal Article↗
PubMed2002

Severity and correlates of liver disease in hepatitis C virus-infected injection drug users.

Between May 1996 and June 1998, 210 members of a cohort of 1,667 hepatitis C virus (HCV)-infected injection drug users (IDUs) were selected for liver biopsy procedure after stratification based on 2 consecutive serum alanine transaminase (ALT) levels. Liver histology, which could be fully evaluated for 207 subjects, was classified by using the modified Ishak scores. At the time of biopsy, the median age of subjects was 41.3 years and the median estimated duration of HCV infection was 20.7 years; 94% were African American; 78% men; 31% were human immunodeficiency virus (HIV) seropositive; and 76% had HCV genotype 1a or 1b. Total modified histologic activity index (MHAI) scores ranged from 0 to 9, and 26.6% had a total MHAI score of 5 or greater. Persons with a total MHAI score of 5 or greater were more likely to be HIV infected (P =.04). Higher fibrosis, indicated by Ishak modified fibrosis scores of 3 to 6, was present in 10.1% of subjects and was found more often in those older than 46 years of age (the highest quartile) (P <.01). Both fibrosis scores of 3 or greater and total scores of 5 or greater were associated with elevated ALT, aspartate transaminase (AST), and gamma-glutamyl transpeptidase (GGT) levels (P <.01). When serial values were considered, the results of liver enzyme testing could reduce the probability of an IDU having a fibrosis score of 3 or greater from 10% to 3%. In conclusion, these data indicate that severe liver disease is uncommon in this urban, HCV-infected IDU cohort, especially in younger persons and those with repeatedly normal liver enzymes.

Adult↗
PubMed2002

Coronary artery calcification, atherogenic lipid changes, and increased erythrocyte volume in black injection drug users infected with human immunodeficiency virus-1 treated with protease inhibitors.

BACKGROUND: Protease inhibitors (PIs) may be associated with accelerated atherosclerosis in individuals infected with human immunodeficiency virus (HIV). We assessed the effects of HIV PIs on subclinical atherosclerosis. METHODS: The lipid profiles, C-reactive protein (CRP) levels, coronary artery calcification (CAC) scores, and blood cell morphologic changes were quantified in 98 black adult participants, aged 25 to 45 years, with HIV-1 infection in Baltimore, Md. Fifty-five participants (56.1%) were taking PIs; 43 participants (43.9%) were not. The Student t and chi(2) tests were used as a means of detecting the between-group differences. RESULTS: Participants in both the PI and non-PI groups were similar in age, sex, body mass index, blood pressure, heart rate, and red and white blood cell counts. Compared with the non-PI group, the PI group had significantly higher serum total cholesterol (4.8 +/- 1.0 vs 3.8 +/- 0.7 mmol/L, P <.001) and LDL cholesterol (2.9 +/- 0.8 vs 2.1 +/- 0.7 mmol/L, P <.001) levels and red blood cell mean corpuscular volume (92.2 +/- 9.3 vs 86.8 +/- 7.2 microm3, P =.048). The CAC scores in the PI group were also higher than those in the non-PI group (11.0 +/- 28.6 [n = 43] vs 1.7 +/- 5.8, P =.043). CAC scores were marginally associated with log-transformed duration of the PI therapy (P =.055). Serum CRP levels remained unchanged (5.5 +/- 13.6 mg/L [n = 45] vs 3.9 +/- 5.5 mg/L, P =.467). Serum total cholesterol level, LDL cholesterol level, red blood cell mean corpuscular volume, and CAC scores were indicated by means of regression analyses to be associated with log-transformed duration of the PI therapy. CONCLUSIONS: The use of PIs is associated with coronary artery calcification, atherogenic lipid changes, and increased erythrocyte volume in individuals infected with HIV-1.

Adult↗
PubMed2002

Health services utilization by injection drug users participating in a needle exchange program.

OBJECTIVE: To determine the characteristics associated with health care and drug treatment utilization among a distinctly high-risk sub-population of injectors participating in a needle exchange program (NEP). METHODS: Between June 1998 and May 1999, study staff collected demographic and health services utilization data on participants of the Baltimore NEP. Odds ratios and logistic regression were used to identify the participant characteristics associateds with utilizing primary health care and drug treatment during the prior 3 years. RESULTS: Among 269 participants, 81% were African-American and 66% were male. Over half (56%) had not graduated from high school, 89% were unemployed, 70% did not have health insurance, and the median age was 39 years. Fifty-eight percent of the participants reported utilizing primary care (i.e., visited a physician or other health care provider) and 44% had utilized drug treatment during the prior 3 years. Primary care utilization was associated with age > or = 39 [adjusted odds ratio (AOR) = 1.82], having health insurance (AOR = 2.16), and exchanging a higher volume of syringes per NEP visit (AOR = 2.45). Recent drug treatment utilization was associated with African-American race (AOR = 0.41), unemployment (AOR = 2.72), having health insurance (AOR = 2.05), and exchanging a higher volume of syringes per NEP visit (AOR = 0.60). CONCLUSIONS: Health insurance was significantly associated with the recent utilization of both primary care and drug treatment, yet only one-third of NEP attenders were insured. Facilitating the uptake of health insurance services at NEP sites may improve the access to health care for drug users who are currently not utilizing the health care system.

Adult↗
PubMed2002

Canadian illicit opiate users' views on methadone and other opiate prescription treatment: an exploratory qualitative study.

Although methadone treatment has been available in North America for decades, only a small proportion of opiate addicts (some 25% of estimated opiate users in Canada) are receiving methadone treatment. Many users have tried methadone treatment, often multiple times, but leave treatment prematurely. Others would not consider it as a worthwhile treatment option for themselves. This exploratory study examines regular opiate users' attitudes towards and experiences with methadone treatment in Canada, primarily setting out to determine what makes methadone an unsuccessful or even an undesirable treatment option for considerably large groups of opiate users. This empirical effort to explore the limitations of existing methadone treatment comes at an appropriate time, when alternative forms of opiate pharmacotherapy treatment are being proposed in Canada as complementary modes of intervention that hope to address the shortcomings of methadone treatment. The rationale for this study were feasibility questions and development efforts for a clinical trial in North America evaluating the effectiveness of using injectable opioids (heroin, dilaudid) in attracting and engaging treatment-resistant opiate users into treatment. Data for this exploratory qualitative study was collected in 1999 through a series of focus groups involving 47 treatment-experienced and treatment-naive opiate users in Vancouver, Montreal, and Toronto, with the objective of identifying key themes and issues on the described topic as a basis for further systematic research.

Adult↗
PubMed2002

Drug user treatment referrals and entry among participants of a needle exchange program.

OBJECTIVE: To compare characteristics of needle exchange program (NEP) participants who requested methadone treatment to those who did not, compare participants who subsequently enrolled into treatment to those who did not enroll, and suggest possible barriers to treatment among NEP participants. METHODS AND MATERIALS: Between 8/94 and 2/97, data pertaining to demographics and drug use were collected from Baltimore NEP participants upon registration. Participants were made aware that referrals to off-site methadone maintenance were available upon request. Odds ratios and multiple logistic regression models were used to compare those who requested treatment to those who did not and those who entered treatment to those who did not enter. RESULTS: Among 2659 NEP participants, 86% were African-American, 28% were female, 9% were employed, and the median age was 38 years. Requesting a drug user treatment referral was associated with female gender [Adjusted Odds Ratio (AOR) = 2.02], age > 38 years (AOR = 1.96), use of speedballs during the past 6 months (AOR = 3.38), and age > 20 years at time of first injection (AOR = 1.59). Among 139 individuals who requested treatment, males were twice as likely as females to enter treatment (OR = 2.45). In an open-ended survey, health insurance (p = .02) and not living with children (p = .01) were associated with drug user treatment entry. CONCLUSIONS: Even though female NEP participants were more likely to request methadone treatment, they were less likely than males to enter treatment. Although NEPs can be a bridge to drug user treatment, these data suggest that barriers to utilizing treatment referrals are important issues to resolve, especially for women who use community needle exchange programs.

Adolescent↗
PubMed2002

Continuity of medical care and risk of incarceration in HIV-positive and high-risk HIV-negative women.

OBJECTIVES: Incarceration rates in the United States have tripled over the past two decades and have increased even more rapidly among women than men. To identify risk factors that predict incarceration in HIV-positive (HIV+) and high-risk HIV-negative (HIV-) women and to evaluate the association between continuity of medical care and risk of incarceration, this analysis was conducted. METHODS: This was a prospective cohort study of HIV+ and high-risk HIV- women enrolled between April 1993 and January 1995 at four urban centers: Providence, Rhode Island; New York, New York; Baltimore, Maryland; and Detroit, Michigan. The HIV Epidemiology Research (HER) Study enrolled 871 HIV+ and 439 high-risk HIV- innercity women between the ages of 16 and 55 years. All participants had a history of injection drug use or high-risk sexual behavior. Interviews, including questions on continuity of medical care and incarceration, were administered at baseline and 6 and 12 months after enrollment. Any incarceration in the 1-year period following enrollment was the main outcome measure. Continuity of care was measured as having seen one healthcare provider for at least 2 years, having received medical care from one usual physician or clinic, and having obtained medical care in a primary care setting as opposed to an emergency room or drug treatment center. RESULTS: Twelve percent of women were incarcerated within 1 year postenrollment. Factors associated with incarceration included recent drug use, prior incarceration, lack of college education, engaging in sex for drugs or money, and having multiple unmet basic needs at the time of enrollment in the study. Continuity of care with a single healthcare provider for more than 2 years prior to enrollment in the study was associated with decreased rates of incarceration even after adjusting for possible confounding factors (OR = 0.67, 95% CI = 0.48 - 0.92). HIV serostatus did not correlate with incarceration. CONCLUSIONS: History of prior incarceration and recent drug use were associated with increased risk of incarceration. Continuity of medical care by a single healthcare provider was associated with decreased likelihood of incarceration, suggesting that the provider may play an important role in designing interventions to prevent incarceration in this high-risk population.

Adolescent↗
PubMed2002

Characteristics of injection drug users who utilize tuberculosis services at sites of the Baltimore city needle exchange program.

OBJECTIVE: To describe characteristics of needle-exchange program (NEP) participants who utilized tuberculosis services from an NEP site. METHODS: Between June 1998 and May 1999, tuberculosis services were advertised and offered to Baltimore, Maryland, NEP participants. Demographic and tuberculosis-specific data were collected on participants who self-selected into services. Analyses were based on being tuberculin skin tested, returning for a skin test reading, and testing tuberculin positive. RESULTS: Among 691 contacts with NEP participants, this service performed 296 tuberculin tests, with an 84% return rate for skin test reading. Participants were 32% female, 87% African American, and 11% employed. Higher frequency of NEP visits was positively associated with requesting tuberculosis services and returning for skin test reading. Among those who returned for skin test reading, longer smoking duration and problems getting food in the past year due to a lack of money were associated with a positive test. CONCLUSIONS: Utilization of a tuberculosis service and high return rates can be achieved among NEP participants without formal recruitment strategies. Frequent exchange appears to facilitate return visits for NEP-based tuberculosis screening, which may imply accessibility for frequent exchangers. More extensive health services at sites of the Baltimore NEP appear to be warranted, with particular attention paid to effectiveness for frequent exchangers.

Adult↗
PubMed2002

Drugs and firearm deaths in New York City, 1990-1998.

Firearm deaths remain among the leading causes of mortality in the United States. Changing law enforcement activities, incarceration, drug use, and socioeconomic conditions may have played roles in the declining rates of firearm deaths during the 1990s. Using records from the Office of the Chief Medical Examiner, we analyzed the role of drugs in firearm deaths in New York City between 1990 and 1998. Positive drug toxicology was present in over half of all firearm death victims during this time. Cocaine, cannabis, opiates, and alcohol accounted for almost all of these deaths with drug-positive toxicology. There were decreases in cocaine- and alcohol-positive toxicology for firearm deaths in New York City starting in the early 1990s; there was a more gradual decrease in heroin-positive toxicology for firearm deaths. Cannabis-positive toxicology for firearm deaths increased in the early part of the 1990s and then decreased starting in the mid-1990s. Although the disparities between minority and white firearm death rates narrowed during this time, minorities remained about three times more likely to be victims of fatal firearm violence than whites in 1998. The highest firearm death rates were among African American and Latino male decedents, with a larger proportion of Latinos testing cocaine or opiate positive, while a larger proportion of African Americans tested cannabis positive. These results suggest a complex role of drugs in firearm-related deaths.

Adolescent↗
PubMed2002

Self-efficacy estimates for drug use practices predict risk reduction among injection drug users.

We used baseline outcome efficacy (OE) estimates for human immunodeficiency virus (HIV) risk reduction to predict subsequent risk reduction 6 months hence among 792 injection drug users in a prospective study. Declines in drug use, frequency of injection, and needle sharing were found among those with high OE scores after adjustment for baseline behavior and antecedent factors. No OE effect was found in multivariate analysis for shooting gallery attendance, a risk that substantially declined in this cohort. OE for needle disinfection was associated with reduced drug risk behaviors, but not for improved needle hygiene practices over time. The self-efficacy model is useful in understanding psychological factors in risk reduction among injection drug users.

Adult↗
PubMed2002

Posttraumatic stress disorder in Manhattan, New York City, after the September 11th terrorist attacks.

Estimates of acute mental health symptoms in the general population after disasters are scarce. We assessed the prevalence and correlates of acute posttraumatic stress disorder (PTSD) in residents of Manhattan 5-8 weeks after the terrorist attacks of September 11, 2001. We used random-digit dialing to contact a representative sample of adults living in Manhattan below 110th Street. Participants were interviewed about prior life events, personal characteristics, exposure to the events of September 11th, and psychological symptoms after the attack. Among 988 eligible adults, 19.3% reported symptoms consistent with PTSD at some point in their life, and 8.8% reported symptoms consistent with a diagnosis of current (within the past 30 days) PTSD. Overall, 57.8% of respondents reported at least one PTSD symptom in the past month. The most common past-month symptoms were intrusive memories (27.4%) and insomnia (24.5%). Predictors of current PTSD in a multivariable model were residence below Canal Street, low social support, life stressors 12 months prior to September 11th, perievent panic attack, losing possessions in the attacks, and involvement in the rescue efforts. These findings can help guide resource planning for future disasters in densely populated urban areas.

Adolescent↗
PubMed2002

Drug use frequency among street-recruited heroin and cocaine users in Harlem and the Bronx before and after September 11, 2001.

We determined if illicit drug use frequency changes after a disaster by comparing drug use frequency in two street-recruited samples of heroin and cocaine users, ages 15-40 years. The users were interviewed between July 11 and November 11 and divided into before- and after-September 11th groups for analysis. The before and after groups were similar in the mean number of days of drug use per month (sniff cocaine 6.8 days vs. 9.4 days, respectively, P =.17; snorted heroin 13.9 vs. 14.0, respectively, P =.96; smoked crack 16.9 vs. 15.6, respectively, P =.96; and smoked marijuana 17.5 vs. 15.3, respectively, P =.36) and in the proportion of daily users: sniffed cocaine 10% versus 17%, respectively (P =.28); snorted heroin 47% versus 40%, respectively (P =.91); smoked crack 33% versus 37%, respectively (P =.68); and smoked marijuana 47% versus 40%, respectively (P =.41). Among street-recruited heroin and cocaine users in Harlem and the Bronx, the frequency of drug use did not increase following the events of September 11, 2001.

Adolescent↗
PubMed2002

Incidence of violence against HIV-infected and uninfected women: findings from the HIV Epidemiology Research (HER) study.

The effect of human immunodeficiency virus (HIV) infection on the incidence of violence against women was addressed in a prospective cohort of HIV-infected and uninfected women. Participants were enrolled between 1993 and 1995 in four US cities and followed up semiannually through 1998. Among 1,087 women with a total accrual of 2,988 person-years (PY) of follow-up, there were 185 reports of abuse (incidence rate = 6.19 per 100 PY). The rate of abuse among HIV-infected women with a CD4+ count less than 350 cells/ micro L was lower than that among HIV-infected women with more CD4+ cells/ micro L or among uninfected women (4.87, 6.92, and 6.44 per 100 PY, respectively). In multivariate analysis, being separated or divorced, having a history of abuse in adulthood, using marijuana, using crack, and having multiple sex partners were each significantly associated with an elevated abuse rate; being older was inversely associated with abuse. Among HIV-infected women, those with fewer CD4+ cells/ micro L continued to show a decreased abuse rate (hazard ratio = 0.55, 95% CI = 0.36, 0.82) after adjustment for these factors. It is important to complement existing and future HIV prevention and intervention strategies with efforts to reduce violence against women.

Adult↗