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D Vlahov

Publications and source records attributed to D Vlahov.

At least 253 records · Page 14Linked to original sources
PubMed1993

Comparison of clinical symptoms of human immunodeficiency virus disease between intravenous drug users and homosexual men.

BACKGROUND: To compare the prevalence of human immunodeficiency virus (HIV)-related clinical symptoms among male intravenous drug users and homosexual men stratified by HIV serostatus and CD4 cell levels. METHODS: A cross-sectional sample using concurrent longitudinal studies of the natural history of HIV-1 infection among intravenous drug users (N = 539) and homosexual men (N = 932) was recruited in Baltimore, Md. Participants were administered a risk behavior interview and physical examination, and had hematologic tests evaluated in a similar calendar period. RESULTS: Both risk groups demonstrated an inverse relationship between frequency of symptoms and CD4 cell count. Fever, night sweats, and lymphadenopathy were not evaluated because pilot data suggested a confounding association with drug injection. Among those with mild to moderate immune suppression, intravenous drug users were significantly more likely than homosexual men to experience fatigue, weight loss, diarrhea, and shortness of breath; to have oral candidiasis, palpable spleen, and lower mean weight on physical examination; and abnormal hematocrit, platelets, and total lymphocyte counts. However, participants in either risk group with CD4 cell levels below 0.2 x 10(9)/L experienced similar frequency of all clinical symptoms. Self-reported oral candidiasis increased fourfold with HIV infection and was as likely in both groups at all CD4 cell levels. Duration and recency of intravenous drug use was not significantly associated with the higher frequency of most clinical symptoms. CONCLUSION: Social factors are an important consideration in evaluating the association between clinical symptoms and HIV immunosuppression. Except for oral candidiasis, there are limitations for the use of clinical symptoms as intermediate outcome measures for HIV infection among intravenous drug users.

Adult↗
PubMed1993

Prevalence and incidence of left ventricular dysfunction in patients with human immunodeficiency virus infection.

The prevalence and incidence of left ventricular (LV) dysfunction was examined in patients infected with the human immunodeficiency virus (HIV). Sixty-nine randomly selected patients diagnosed with HIV infection who were followed in HIV clinics were prospectively evaluated by 2-dimensional echocardiography. Mean follow-up duration was 11 months. Additionally, 39 consecutive HIV-infected patients referred to the Cardiomyopathy Service and found to have LV dysfunction by 2-dimensional echocardiography were also studied. Of the 39 referred patients, 34 (87%) were referred for recent onset, unexplained, congestive heart failure. During this time, the HIV clinic population comprised 1,819 alive and actively followed patients; the 39 cardiomyopathy referrals therefore constituted a crude rate of 2.1% for this population. Of the 69 prospectively studied patients without clinical heart disease, a 14.5% prevalence of global LV hypokinesia and an incidence of 18%/patient-year were found. During a maximal 18-month follow-up period, 4 prospective patients (5.8%) developed symptoms of congestive heart failure. A greater proportion of prospective and referred patients with LV dysfunction had CD4 counts < 100/mm3 (62 and 79%, respectively) than did that of those without LV dysfunction (35%). In conclusion, the high rate of unexpected LV dysfunction in this HIV-infected population suggests that early cardiac contractile abnormalities may involve a significant number of patients, most of whom have low CD4 counts. A subgroup of these patients appears to progress to symptomatic congestive heart failure.

Adult↗
PubMed1993

Differences in risk factors for human immunodeficiency virus type 1 seroconversion among male and female intravenous drug users.

To examine sex-specific risk factors for human immunodeficiency virus (HIV) type 1 seroconversion among intravenous drug users, the authors conducted a nested case-control study in Baltimore, Maryland, from 1988 to 1992 comparing 146 seroconverters and 539 HIV seronegative controls. Controls were matched on sex, race, date of study entry, and duration of follow-up. Risk factor data were obtained from interviews conducted at the first seroconversion visit for the case and the closest visit for the corresponding seronegative control. Since test results were not available until several weeks after interview, both interviewers and participants were unaware of seroconversion status at the time of interview. When data were analyzed using conditional logistic regression techniques, the variables which were significantly associated with seroconversion among male intravenous drug users included age less than 35 years, a sexually transmitted disease within the past 6 months, lifetime history of syphilis, and current intravenous drug use with an abscess at the injection site. Among women, only a history of three or more sex partners was positively associated with seroconversion and having a biological child under age 18 years was inversely associated with HIV seroconversion. Although the small sample size may have limited the ability to ascertain differences in risks of seroconversion among males and females, these data suggest that sexual transmission contributes to HIV infection among intravenous drug users, especially women.

Adult↗
PubMed1993

Prevalence and incidence of hepatitis C virus infection among male prison inmates in Maryland.

To identify incidence of antibody to hepatitis C virus among 265 male prison inmates, we assayed paired serum specimens obtained at intake in 1985-1986 with follow-up specimens in 1987. Intake prevalence was 38 percent. Seroincidence was 1.1/100 person years in prison. This finding might reflect saturation of high-risk subgroups or possibly reduced frequency of exposures following incarceration.

Adult↗
PubMed1993

Detection of human immunodeficiency virus type 1 infection by polymerase chain reaction in a cohort of seronegative intravenous drug users.

The frequency of serologically undetected human immunodeficiency virus type 1 (HIV-1) infection among a large cohort of seronegative intravenous drug users (IVDUs) was determined by polymerase chain reaction (PCR). In total, 2159 blood specimens were obtained from 945 seronegative IVDUs; of these, 182 had 1 specimen, 339 had 2, 397 had 3, and 27 had 4 semiannual specimens. No proviral DNA was detected in 2134 (98.8%) of the samples. Specimens from 7 persons (0.3%) were reactive by PCR. Within 6 months, all 5 of these 7 who returned for follow-up visits had seroconverted. Serum from 19 persons (0.9%) were equivocal by PCR analysis, that is, single primer pair amplification; 1 person seroconverted while others subsequently remained seronegative and nonreactive by PCR. The concordance between PCR and serology was 98.6%. It is concluded that immunosilent HIV-1 infection is uncommon and that serologic screening for HIV-1 antibodies is highly sensitive in this population.

Adolescent↗
PubMed1993

Elevated serum levels of neopterin but not beta 2-microglobulin in HIV-1-seronegative injecting drug users.

OBJECTIVE: To determine whether injecting drug use is associated with cellular immune activation in the absence of HIV-1 infection. DESIGN: Serum levels of neopterin and beta 2-microglobulin (beta 2M) were measured cross-sectionally in injecting drug users (IDU) enrolled in a prospective study. SUBJECTS AND METHODS: Two hundred and nineteen HIV-1-seronegative, healthy heterosexual black male IDU aged 21-49 years were selected from the Baltimore-based AIDS Linked to Intravenous Experiences (ALIVE) study. The possibility of including subjects in the process of seroconverting to HIV-1 was minimized by restricting the study to individuals who remained seronegative 6 months after the specimens used for analysis were collected. RESULTS: Mean serum beta 2M levels were not statistically different among groups of IDU whose usual pattern of injection was at least once a day for up to 3 consecutive days (daily users; n = 65), less than once per day (less-than-daily users; n = 75), or not at all for at least 2 weeks (non-recent users; n = 79). In contrast, the mean neopterin level was significantly (P = 0.039) greater in daily users (6.17 nmol/l) than in the other two groups (5.07 and 5.19 nmol/l, respectively, which were not statistically different). These results were not affected, by the frequency of using borrowed non-sterile works or by other demographic and risk factor variables. CONCLUSIONS: Frequent injecting drug use may be independently associated with a small elevation of serum neopterin levels, but not beta 2M levels. Although the occurrence of a type I error in this sample cannot be completely excluded, serum neopterin may be more sensitive than serum beta 2M in detecting activation of immunocompetent cells associated with frequent injecting drug use in this population.

Adult↗
PubMed1993

Socially desirable responding and self-reported HIV infection risk behaviors among intravenous drug users.

This study examined the extent to which self-report of human immunodeficiency virus (HIV) risk behaviors might depend upon socially desirable response tendencies, and whether socially desirable responding might serve as a confounding variable in the study of risk behaviors and HIV serostatus. The subjects were 2885 intravenous drug users participating in the ALIVE study in Baltimore, Maryland. Participants completed an interview and were tested for HIV serostatus. The interview covered HIV risk behaviors, and included established scales to measure 'self-deception' and 'impression management', two separate dimensions of socially desirable responding. Seven items for each scale were scored true/false, with a summary score used for analysis. Scores on self-deception and impression management were inversely related to self-reports of sharing injection equipment, injecting at shooting galleries, and injecting more than once a day. Neither self-deception nor impression management was associated with cocaine use. Self-reported receptive anal intercourse was associated inversely with self-deception but not with impression management. HIV serostatus was not associated with social desirability, and statistically controlling for social desirability had a negligible impact on the magnitude of associations between risk behaviors and HIV serostatus. The results indicate that measures of social desirability may be used to ascertain sensitive areas of inquiry in interviews of intravenous drug users.

Adolescent↗
PubMed1993

Potential use of mass media to reach urban intravenous drug users with AIDS prevention messages.

To access the potential of using the mass media to reach urban intravenous drug users (IVDUs) with AIDS prevention messages, we: 1) questioned 353 participants in a Baltimore IVDU cohort study on their media use and sources of AIDS information, 2) analyzed data on Baltimore AIDS public service announcement (PSA) airings during a 3-month period, and 3) discussed with media executives their willingness to air a variety of potential AIDS messages. Forty-seven percent of all respondents reported that they learned the most about AIDS from television. Participants watched television a median of 28 hours/week; 52% of IVDUs listened to ratio > or = 12 hours/week. Eight hundred eleven AIDS television PSAs were aired; 37% of PSAs were placed on news programs; 53% of respondents watched news programs. Acceptability of hypothetical prevention messages (e.g., on sexual abstinence, condom use, or safer drug use practices) varied with media reach (national vs local) and type (television vs radio). We conclude that media could reach IVDUs with AIDS prevention messages. Television could be used to direct IVDUs to local prevention programs and provide safe/safer sex messages. Explicit and detailed AIDS prevention messages would be acceptable to some local radio stations.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Effect of chronic substance abuse on the neuropsychological performance of intravenous drug users with a high prevalence of HIV-1 seropositivity.

Limited data are available on cognitive performance in populations of intravenous drug users during the early, asymptomatic stages of human immunodeficiency virus type 1 (HIV-1) infection. Between 1988 and 1990, 151 participants from the AIDS Link to Intravenous Experience (ALIVE) Study in Baltimore, Maryland, were evaluated neuropsychologically on a semiannual basis. This analysis focused on whether history of substance abuse influenced neuropsychological test performance. At baseline, 102 participants were HIV-1-seropositives who were free of acquired immunodeficiency syndrome and 49 participants were seronegative. Multivariate analyses, adjusting for correlation of repeated outcome measures, were conducted to determine predictors of neuropsychological functioning. Effects of the frequency of reported past use of marijuana, heroin, cocaine, barbiturates, and alcohol were not statistically associated with performance on the tests. Age and education were the most important predictors of test performance, and a significant practice effect was observed for most measures. After adjustment for age, education, the practice effect, and frequency of drug use, neuropsychological performance over time did not vary by HIV-1 serostatus. Overall, after acutely intoxicated individuals were excluded, neither frequency of drug and alcohol use nor HIV-1 seropositivity significantly influenced neuropsychological test performance over a 1-year period.

Adult↗
PubMed1992

Cancer of the pancreas and drinking water: a population-based case-control study in Washington County, Maryland.

A case-control study was done to assess a potential association between drinking water and pancreatic cancer in Washington County, Maryland. Cases of pancreatic cancer occurring from 1975 through 1989 were identified from the cancer registry. Controls were selected from the private 1975 census of Washington County. There were 101 cases and 206 controls. Chlorinated municipal water was used as a source of drinking water by 79% of cases and 63% of controls, yielding a significant odds ratio of 2.2. Adjustment for age and smoking had almost no effect on the risk, although both age and smoking were independently associated with an increased risk of pancreatic cancer. Although these findings must be interpreted with caution because of limitations in exposure assessment, these results have implications for the prevention of pancreatic cancer because chlorination of water is so widely practiced.

Adult↗
PubMed1992

Changes in T-lymphocyte subsets in intravenous drug users with HIV-1 infection.

OBJECTIVE: To evaluate changes in T-cell subsets in prevalent human immunodeficiency virus type 1 (HIV-1) seronegative and seropositive intravenous drug users (IVDUs) and in HIV-1 seropositive IVDUs with known time of seroconversion. DESIGN: Cohort study with a median 18-month follow-up. SETTING: Community-based clinic established to study the natural history of HIV infection in IVDUs. SUBJECTS: Eight hundred fifty-nine self-referred IVDUs aged 18 through 49 years who injected drugs within the last 10 years and who did not have an AIDS (acquired immunodeficiency syndrome)--defining illness; 152 were seronegative for HIV-1, 621 were seropositive, and 86 seroconverted during the study. OUTCOME MEASURES: Proportions and absolute numbers of lymphocytes and CD3, CD4, and CD8 T cells as determined at 6-month intervals by flow cytometry and complete blood cell counts with automated differential. RESULTS: Median numbers of CD4 lymphocytes at enrollment were 1061/microL (1.06 x 10(9)/L) for seronegative IVDUs, 508/microL for seropositive IVDUs, and 733/microL for those who seroconverted (enrolled a median of 4.5 months after seroconversion); the corresponding figures for CD8 lymphocytes were 628, 894, and 889/microL, respectively. Median rates of decline in absolute numbers and percentages of CD4 lymphocytes per 6 months were 7.6/microL (0.0%) for seropositive IVDUs and 55.1/microL (1.9%) for IVDUs who seroconverted (median follow-up after seroconversion was 12 months). Multivariate regression analysis that incorporated the within-individual correlation of the CD4 lymphocyte counts showed no significant change in these cells over time and no change due to use of drugs. CONCLUSION: Our data suggest that progression of HIV-1 infection in IVDUs, as reflected in decline of CD4 cell counts, is no more rapid than that reported for other risk groups.

Adult↗
PubMed1992

Prevalence of tuberculin positivity and skin test anergy in HIV-1-seropositive and -seronegative intravenous drug users.

OBJECTIVES: --To identify differences in purified protein derivative (PPD) tuberculin positivity and skin test anergy rates by human immunodeficiency virus (HIV) serostatus, CD4+ lymphocyte count, and other risk factors in intravenous drug users (IVDUs); and to evaluate the appropriateness of the Centers for Disease Control (CDC)--recommended definition for a positive PPD tuberculin skin test result in HIV-1-seropositive patients. DESIGN: --Nested case-control and cross-sectional analyses. SETTING: --Community-based cohort of IVDUs. PATIENTS: --Two hundred sixty HIV-1-seropositive and -seronegative IVDUs, drawn from an unselected cohort, were skin-tested for sensitivity to PPD tuberculin, mumps, and Candida antigens using the Mantoux method. OUTCOME MEASURES: --Positivity to PPD tuberculin, skin test anergy. RESULTS: --Even using the CDC definition of an induration 5 mm or greater in diameter in HIV-1 seropositives, this group was substantially less likely to be PPD tuberculin positive than HIV-1 seronegatives (13.8% vs 25.2%; P = .02). In the HIV-1 seropositives the relative odds of being PPD positive varied depending on whether 10 mm or greater (odds ratio [OR], 0.3; 95% confidence interval [CI], 0.2 to 0.7), 5 mm or greater (OR, 0.5; 95% CI, 0.2 to 0.9), or 2 mm or greater (OR, 0.7; 95% CI, 0.4 to 1.3) was used to define a positive test result. The mean diameter induration in the HIV-1-seropositive group was 2.6 mm vs 5.4 mm in the seronegative group (P = .005). Skin test anergy (to mumps and Candida) appeared to explain the differential. Anergy was substantially higher in the HIV-1 seropositive group and increased as the CD4+ lymphocyte count fell (chi 2 for linear trend, 24.5; P less than .0001). An inverse linear trend for PPD positivity and CD4+ lymphocyte count was also observed (chi 2 for trend, 6.1; P = .01). In multivariate analyses, being 35 years of age or older and being HIV-1 seronegative were significantly associated with PPD positivity, while history of previous police arrest was of borderline significance. Only HIV-1 seropositivity was significantly associated with anergy. CONCLUSIONS: --These findings show that CDC-recommended definition of an induration 5 mm or greater in diameter for PPD tuberculin positivity in HIV-1 seropositives significantly underestimates the "true" infection rate (using the PPD positivity rate in HIV-1 seronegatives as the criterion standard). A definition of 2 mm or greater would appear to be a better cutoff for reducing misclassification in HIV-1 seropositives. This study also confirms that delayed-type hypersensitivity is seriously depressed in HIV-1 seropositive IVDUs and that anergy testing is mandatory to properly assess a negative PPD test result.

Adolescent↗
PubMed1992

Genetic vulnerability to drug abuse. The D2 dopamine receptor Taq I B1 restriction fragment length polymorphism appears more frequently in polysubstance abusers.

Alcoholics are more likely than nonalcoholics to display the Taq I A1 restriction fragment length polymorphism of the D2 dopamine receptor gene, according to four of six studies that examined alcoholics and controls. The current study examines whether the association observed in alcoholism might extend to other addictive substances by examining D2 dopamine receptor Taq I A and B restriction fragment length polymorphisms in polysubstance users and controls free of significant substance use. We hypothesized a stronger association for the B1 restriction fragment length polymorphism since it lies closer to dopamine receptor protein coding and 5' regulatory regions. Heavy polysubstance users and subjects with DSM-III-R psychoactive substance use diagnoses displayed significantly higher Taq I B1 frequencies than control subjects; Taq I A1 results for these comparisons were less robust. These results are consistent with a role for a D2 dopamine receptor gene variant marked by these restriction fragment length polymorphisms in enhanced substance abuse vulnerability.

Alcoholism↗