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Biomedical subjects

Dennis G Fisher

Publications and source records attributed to Dennis G Fisher.

At least 19 recordsLinked to original sources
PubMed2007

Reliability and criterion-related validity of self-report of syphilis.

OBJECTIVE: To determine the test-retest reliability, sensitivity and specificity, and criterion-related validity of the Risk Behavior Assessment (RBA) syphilis questions. The RBA is a standardized instrument that has been used in several studies of STDs in drug users. METHODS: For the test-retest reliability study, 219 injection drug users completed the RBA twice within a 48-hour period. To determine criterion-related validity, 207 individuals, who also completed the RBA, were tested with the rapid plasma reagin test (RPR), and 206 individuals were also tested with the Serodia Treponema pallidum particle agglutination test (TP-PA). RESULTS: The test-retest reliability for the question "How many times have you been told by a doctor or a nurse that you had syphilis?" was 0.78. The test-retest reliability for the question "In what year were you last treated for syphilis?" was 0.89. For the comparison of self-report with the RPR test, the sensitivity of self-report was 46.2% and the specificity was 95.7%. For the comparison of self-report with the TP-PA test, the sensitivity of self-report was 37% and the specificity was 97.7%. CONCLUSIONS: Self-reports of syphilis infection history were found to have good reliability, excellent specificity, and moderate sensitivity. These characteristics need to be taken into account in any study using these self-report items.

Adult↗
PubMed2006

Internet access and use among homeless and indigent drug users in Long Beach, California.

There has been a growing interest in using the Internet to access a variety of populations for prevention education and health care. It is not clear that this is viable for homeless and other marginalized populations. The purpose of this study was to describe Internet access and use among a sample of homeless and indigent drug users. A brief questionnaire was developed to assess computer ownership, use, email, and Internet access and use. Participants were recruited through a community-based human immunodeficiency virus (HIV) prevention program. 265 participants completed the questionnaire. While 55% had ever used a computer in their lifetime, only 25% had ever owned a computer, 24% had ever had their own email account, 33% had access to a working computer in the last 30 days, 10% had sent or received email in the last 30 days, and 19% had surfed or accessed information on the Internet in the last 30 days. Logistic regression predicting lifetime use of a computer showed predictive factors of having completed high school (Odds Ratio [OR] = 4.5; 95% Confidence Interval [CI] = 2.41, 8.38) and number of days used amphetamines in the last 30 days, per 5 days of use (OR = 1.64; 95% CI = 1.18, 2.27). Inversely related were age, per 5 years of age (OR = 0.78; 95% CI = 0.65, 0.93) and number of days used marijuana in the last 30 days, per 5 days of use (OR = 0.97; 95% CI = 0.76, 0.99). Very low access and usage suggest that Internet-based public health education models be reexamined for this population. The association with amphetamine use may indicate a facilitating effect of amphetamine by heightening awareness and increasing wakefulness.

Access to Information↗
PubMed2006

Follow-up for medical care among drug users with hepatitis C.

Prevalence of hepatitis C (HCV) in injection drug users (IDUs) is high and once HCV has been detected, follow-up medical care is essential. Six hundred and one current and former IDUs who tested positive for HCV antibodies received referrals for medical care. Twenty-four percent (147) of participants returned to be interviewed regarding their medical follow-ups. Of these, only 42% (61) had sought additional medical care in the form of further liver or blood tests or liver ultrasound. Four variables predicted seeking medical care: (a) ever being in residential drug treatment, (b) ever trading sex for money, (c) self-reported homelessness, and (d) living in one's own apartment or house. Having income from a job was inversely associated with seeking medical care. Knowledge of HCV infection alone does not mean that IDUs will seek medical care. Additional education concerning medical care and treatment options are needed to address IDU needs.

Adult↗
PubMed2006

Depression as measured by the Beck Depression Inventory-II among injecting drug users.

This study conducts a confirmatory factor analysis of the Beck Depression Inventory-II (BDI-II) with a sample of 598 individuals who reported recent injecting drug use. Findings indicate that out of four models tested, the best model for this sample is a three-factor solution (somatic, affective, and cognitive) previously reported by Buckley, Parker, and Heggie. The findings that nearly 50% of participants provided BDI-II scores indicating significant depressive symptomatology reveals that these individuals are in need of treatment for their psychiatric symptoms as well as substance use. Somatic symptoms are endorsed more strongly than affective or cognitive symptoms of depression, suggesting a possible, but yet poorly defined, relationship between depressive symptomatology and drug use that centers on shared somatic symptomatology.

Adolescent↗
PubMed2006

Hepatitis and human immunodeficiency virus co-infection among injection drug users in Los Angeles County, California.

This study examined the prevalence of hepatitis A (HAV), B (HBV), C (HCV), and Human Immunodeficiency Virus (HIV) co-infection among Injection Drug Users (IDUs) in Los Angeles County, California, and predictors of multiple infections in this population. Six hundred seventy-nine IDUs were recruited from October 2002 through June 2004. Participants completed questionnaires to elicit demographic, drug and sex risk information, and were tested for hepatitis A, B, C and HIV.A linear regression model predicting the total number of infections (0 to 4 possible) was constructed. Significant associations were found between HAV and HBV infection, HAV and HCV infection, and HBV and HCV infection. Predictors of total co-infections included age of first injection, lifetime years in jail, and Hispanic ethnicity. Latinos had the highest proportion of HAV and HBV co-infection with HCV. The total number of co-infections, especially those co-infected with all three of the hepatitis infections, was unexpectedly high.

Adolescent↗
PubMed2006

Health services usage by Alaskan injection drug users.

OBJECTIVES: The purpose of this study was to explore health services usage among injection drug users in Anchorage, Alaska. DESIGN: 645 participants were recruited as part of a federally funded study of needle exchanges. They completed a health services usage questionnaire that elicited information on use of a health care provider (physician or nurse) and emergency room services. Chi-square and t-tests were used for the bivariate analyses, and multiple logistic regression was used to develop the final predictive models. RESULTS: The majority of respondents (n = 646) were male (77 percent). Race/ethnicity included 58 percent White, 22 percent Alaska Native, and 20 percent African American. The multivariate model predicting accessing a health care provider (HCP) included ever having had chlamydia (OR 2.7, CI 1.6, 4.5), current income from welfare or public assistance (OR 2.6, CI 1.7, 3.9), current income from disability (OR 5.0, CI 2.2, 11.4), current income from SSI (OR .30, CI .12, .77) and the number of days in the last 30 used opiates other than heroin (OR 1.04, CI 1.002, 1.078). The multivariate model predicting use of an emergency room (ER) was similar to that predicting use of an HCP, with the additional finding of a negative association between being African American and ER use. CONCLUSION: The role of public assistance benefits enabling access to health care for IDUs has policy implications. Large public programs, such as the Indian Health Service, paid for much of the health care received by the IDUs recruited as part of this study.

Adult↗
PubMed2006

Recreational Viagra Use and Sexual Risk among Drug Abusing Men.

Until recently, the Viagra connection to HIV was anchored in older adults. However, CDC investigation showed stability in 50+ HIV diagnoses on the heels of upward trends in risk indicators among men who have sex with men (MSM) and substance abusing populations. Signs have increasingly pointed to recreational drug use among younger populations, to which Viagra is being added to the mix. Currently, the field is still locating the substance abuse, sexual risk and age-related dimensions of Viagra misuse. Recent studies identify it primarily as substance abuse, but the majority reports a combination of risky sex and risky drug use. At the very least, Viagra appears related to the enhancement of sexual experience or performance, even when it is used to compensate for erectile dysfunction caused by other drugs-either illicit or prescribed (e.g., antidepressants and highly active antiretroviral therapy or HAART). The populations studied, however, frequently have limited the generalizability of findings. This report analyzes the relationship among Viagra, Club Drugs and HIV sexual risk behavior in drug using men with a sample diverse in sexual orientation and demographic scope. Participants were 640 males recruited from three HIV prevention programs in Los Angeles County. Mean age was 43.97 years, ranging from 18.7 to 70.3 with almost 25% over 50. Sexual orientation was 79% heterosexual, 8% bisexual and 12% gay. Racial composition was 45% white, 35% black and 19% Hispanic. NIDA's Risk Behavior Assessment and a Club Drug/Viagra addendum were used to collect socio-demographic, substance use and sexual risk data. Multiple logistic regression models were constructed along with chi-square tests of association and some t-tests. White race was a major risk factor. No age effect was found. MSM were more likely to use Viagra. Insertive anal sex was a significant co-factor among heterosexual Viagra users involved in transactional sex with women. In the overall sample and the subsets of heterosexual, MSM, younger and older men, predictive models all identified club or designer drugs as significant co-factors in the use of Viagra. Different patterns of drug co-factors were observed for each subset. We detected consistent positive associations between the use of Viagra and the use of amphetamines immediately before or during sex. Viagra use has moved into a new generational context and now complicates the sexual risk and intervention equations for all men, particularly MSM as well as more hidden subgroups.

Journal Article↗
PubMed2004

Nicotine dependence and HIV risk behaviors among illicit drug users.

This study was concerned with examining the relation between nicotine dependence and HIV risk behaviors in a sample of 297 out-of-treatment drug users. A number of significant relationships were found between nicotine dependence and HIV risk behaviors. Crack-smoking injectors were found to have a higher degree of nicotine dependence when compared with exclusive injectors or exclusive crack smokers. Participants' impulsivity may be one possible reason why nicotine dependence is related to HIV risk behaviors. The results also suggest that drug abuse programs make available smoking cessation programs.

Adolescent↗
PubMed2003

Needle exchange and injection drug use frequency: a randomized clinical trial.

Despite a lack of evidence that needle exchange programs (NEPs) cause an increase in injection drug use, there are still concerns over fostering increased injection behavior with NEPs. The design was a randomized controlled trial conducted from May 1997 to June 2000 comparing injection drug users (IDUs) who are randomly assigned to have access to an NEP versus training in how to purchase needles and syringes (NS) at pharmacies. Of 653 IDUs recruited into the study, 600 were randomized: 426 were followed-up at 6 months, and 369 were followed-up at 12 months. Four hundred ninety were followed up at least once. There was no difference in the number of injections over time between the NEP and the Pharmacy Sales arms of the study or in the percentage of positive urine test results over time between the NEP and the Pharmacy Sales arms of the study for morphine and amphetamine. The decrease in the presence of cocaine was marginally greater between the arms of the study. The results do not support the hypothesis of NEPs causing an increase in injection drug use. This clinical trial provides the strongest evidence to date that needle exchanges do not produce this negative effect.

Adult↗
PubMed2003

Comparison of different HCV viral load and genotyping assays.

BACKGROUND: We report an interlaboratory comparison of methods for the determination of hepatitis C virus (HCV) serum load and genotype between a recently, established molecular laboratory at the Alaska Native Medical Center (ANMC) and two independent laboratories using different assays. At ANMC, a Real-time quantitative RT-PCR amplification methodology (QPCR) has been developed in which HCV viral loads are determined by interpolation of QPCR results to those of standards calibrated to the World Health Organization (WHO) First International Standard for HCV. HCV genotype is subsequently determined by direct sequencing of the DNA fragment generated from the QPCR assay. OBJECTIVES AND STUDY DESIGN: The above methods were statistically compared to results obtained for the same patient sera by two independent laboratories using different commercially available viral load assays; Quantiplex HCV RNA (Bayer Diagnostics) and Amplicor HCV Monitor (v 2.0) (Roche Molecular Systems), as well as two different genotyping assays; restriction fragment length polymorphism (RFLP) and INNO-LiPA HCV II (Innogenetics). RESULTS: ANMC's Real-time QPCR HCV viral load results compared moderately well with those obtained by the Quantiplex HCV RNA method (R2=0.3813), and compared quite well with recent lot numbers of Amplicor HCV Monitor in which viral loads are derived in IU/ml (R2=0.6408), but compared poorly with earlier lot numbers of Amplicor HCV Monitor in which viral loads were derived in copies/ml (R2=0.0913). The ANMC direct sequencing method for genotype determination compared moderately to very well with both the RFLP (84-86%) and INNO-LiPA (85-97.5%) methods. CONCLUSIONS: These viral load comparisons highlight the discrepancies that may occur when patient HCV viral loads are monitored using different types of assays. Comparison of HCV genotype by different methods is more reliable statistically and important clinically for predicting probability of response to antiviral therapy. However, viral loads are important for monitoring response once therapy has begun.

Evaluation Studies as Topic↗
PubMed2003

A cognitive-behavioral intervention to reduce HIV risk behaviors in crack and injection drug users.

This paper presents the results of a study evaluating the efficacy of a theory-based cognitive-behavioral intervention to reduce HIV risk among street-based crack and injection drug users not currently in drug treatment in Long Beach, California. A nine-session, 4-month enhanced intervention (including HIV counseling and testing) was compared to a two-session standard counseling and testing intervention developed by the National Institute on Drug Abuse (NIDA) in terms of their efficacy for reducing drug- and sex-related risk behaviors. The theory-based enhanced intervention rarely was found to be different from NIDA's standard counseling and testing intervention in reducing both drug- and sex-related risks, as indicated by cessation and/or reduction of drug use (measured by urine test and self-report), entry into drug treatment, and increased frequency of condom use. One of the few significant effects was that the enhanced intervention significantly increased injecting drug users' use of their own injection equipment. On the other hand, for both interventions, most risk behaviors were significantly reduced. It is concluded that the theory-based cognitive-behavioral intervention has limited advantage over the standard intervention in terms of both magnitude and frequency of HIV risk reduction achieved by high-risk, active drug users.

Adult↗
PubMed2003

Use of emergency room services by out-of-treatment drug users in Long Beach, California.

The purpose of this study was to investigate the use of emergency room services among out-of-treatment drug users in Long Beach, CA. Primary data collection occurred between 1991-1996. The study setting was a community-based location through which out-of-treatment drug users were recruited using a standard research protocol. The original study randomized 1,728 participants into a standard or enhanced HIV prevention protocol. Data were collected longitudinally at two points in time, with 1,201 returning for follow-up interview. Standardized instruments were used at baseline and follow-up. Logistic regression and test-retest reliability were performed using the SAS System. Factors associated with emergency room use included income from public assistance sources, ever using other opiates, income less than 500 dollars in the last month, reporting White race/ethnicity, and HIV positive serostatus. Having income from public assistance programs is highly predictive of emergency room use in out-of-treatment drug users.

Adult↗
PubMed2003

Employment retention of health care providers in frontier areas of Alaska.

OBJECTIVES: The objectives of this study were to: describe the length of employment of health care providers in rural Alaska; assess whether there are differences in length of employment among community health aides, medical doctors, and nurses; and determine whether provider length of employment is significantly increased following implementation of telemedicine. STUDY DESIGN: We conducted a prospective cohort study of length of employment among health professionals in rural Alaska, and identified the cohort based on current employment status of community health aides, medical doctors, and nurses. METHODS: Employment data were collected from four Alaska Native regional health corporations. Kaplan-Meier product-limit survival analysis was used to assess employment length. The Mantel-Haenszel log-rank test was used to test the difference between retention (survival) curves among doctors, nurses, and community health aides for all four regional health corporations combined. Data included provider hire date, termination date, and position title. Fifty seven percent of the data points were right-hand censored. RESULTS: The community health aides (median (Mdn) = 1186 days) were retained significantly longer than either the doctors (Mdn = 596 days), or the nurses (Mdn = 408 days), who were not significantly different from each other (log-rank chi2 (2, N = 996) = 68.30, p = 0.0001). CONCLUSIONS: Our findings document that community health aides in the region retain their jobs significantly longer than doctors and nurses. Findings highlight the problem of providing an adequate health work force in rural areas.

Alaska↗
PubMed2003

Validity of injecting drug users' self report of hepatitis A, B, and C.

OBJECTIVE: To test the validity of drug users self-reports of diseases associated with drug use, in this case hepatitis A, B, and C. DESIGN: Injecting drug users (n = 653) were recruited and asked whether they had been diagnosed previously with hepatitis A, B, and/or C. These self-report data were compared to total hepatitis A antibody, hepatitis B core antibody, and hepatitis C antibody seromarkers as a means of determining the validity of the self-reported information. SETTING: Anchorage, Alaska. PARTICIPANTS: Criteria for inclusion included being at least 18-years old; testing positive on urinalysis for cocaine metabolites, amphetamine, or morphine; having visible signs of injection (track marks). INTERVENTION: Serological testing for hepatitis A, B, and C. MAIN OUTCOME: Findings indicate high specificity, low sensitivity, and low kappa coefficients for all three self-report measures. RESULTS: Subgroup analyses revealed significant differences in sensitivity associated with previous substance abuse treatment experience for hepatitis B self-report and with gender for hepatitis C self-report. CONCLUSION: Given the low sensitivity, the validity of drug users, self-reported information on hepatitis should be considered with caution.

Adolescent↗
PubMed2002

Relationship among gender, depression, and needle sharing in a sample of injection drug users.

The authors explored the relationships among gender, needle sharing, and depression in a sample of 392 male and 121 female street drug users. Using the Risk Behavior Assessment (National Institute on Drug Abuse, 1991) and the Beck Depression Inventory-2 (A. T. Beck, R. A. Steer, & G. K. Brown, 1996), the authors found that women reported higher levels of depression than men and that sharers endorsed higher levels of depression than nonsharers. Further, the authors found that female sharers reported the highest levels of depression of all groups, that is, as compared with male sharers, female nonsharers, and male nonsharers, who did not differ from one another. This suggests the presence of a special dynamic between gender and depression that is related to higher rates of needle sharing among women.

Adolescent↗
PubMed2002

Selection effect of needle exchange in Anchorage, Alaska.

Participation bias (selection bias) may be a problem in studies that attempt to evaluate the effects of needle-exchange programs (NEPs). The present study looked at only those injection drug users (IDUs) who were randomly placed in the needle-exchange condition in a two-arm randomized clinical trial of needle exchange. Time to follow-up between the experimental NEP condition (n = 296; median = 261 days) and pharmacy sales condition (n = 304; median = 256 days) was not statistically different [chi(2) (1, N = 600) = 0.42, P =.52]. Within the NEP condition, a similar analysis comparing time to follow-up between IDUs who used the NEP (n = 65; median = 199 days) and those who refrained from using the NEP (n = 231; median = 286 days) was highly significant, chi(2) (1, n = 296) = 17.3, P=.0001. The final logistic regression model predicting use of the NEP was the log 10 transformation of the number of times injected heroin in the last 30 days (odds ratio [OR ]=4.9, confidence interval [CI ]2.8, 8.9), ever injected amphetamine in the last 30 days (OR =4.9, CI 1.09, 22.5), and ever shared injection equipment in the last 30 days (OR =2.9, CI 1.5, 5.5). Within the NEP condition, follow-up rates differed between those who used the NEP and those who did not use it. Of drug users randomly assigned to an NEP, the ones who actually used the NEP had higher levels of drug use. Predictors of who used the NEP were consistent with the studies of Hagen et al. This study demonstrates that selection bias occurs among IDUs who use NEPs.

Alaska↗
PubMed2002

Needle and syringe cleaning practices among injection drug users.

Bleach-mediated disinfection (BMD) of needles and syringes (NS) has been advocated as a risk-reduction intervention against HIV among injection drug users (IDUs). The effect of needle exchange on the BMD practices of 176 NS-sharing IDUs was evaluated. IDUs were randomly assigned to either 1) Pharmacy Sales Condition, access to NS via legal sales of nonprescription NS; or 2) Needle Exchange Condition, with additional access to NS via an experimental needle exchange program. Repeated measures analysis revealed a main effect of time on BMD, no effect of assignment condition, and no time by assignment interaction. Logistic regression revealed IDUs who traded sex for money or drugs were less likely to practice BMD, and IDUs who reported a reduced number of sex partners were more likely to practice BMD. Future interventions should incorporate behavioral BMD components and address the concerns of those who trade sex for money or drugs.

Adolescent↗