Biomedical subjects

N M Graham

Publications and source records attributed to N M Graham.

At least 55 records · Page 3Linked to original sources

PubMed1996

The role of immunologic and viral markers in predicting clinical outcome in HIV infection.

OBJECTIVE: In an ideal world, one clinical marker would explain all the variance in a disease system. In reality, however, this is rarely the case and HIV disease is no exception. This review considers several specific markers that have demonstrated some use in clinical trials and/or epidemiologic studies of antiretroviral therapy. DISCUSSION: CD4 lymphocyte count, HIV viral load and perhaps immune activation markers can be used to measure the activity of antiretroviral therapy. Some recent studies are presented and the results discussed. CONCLUSION: Sustained improvements in several markers (particularly HIV viral load and CD4 cell count) in combination appear to be the most predictive of clinical benefit. No current viral or immunologic markers adequately reflect toxicities attributable to antiretroviral therapy. Lamivudine/zidovudine combination therapy leads to sustained changes in several markers, and appears to be well tolerated. This may translate into significant clinical benefit but the duration of such benefit remains unknown.

Biomarkers↗

PubMed1996

Serum hormones in men with human immunodeficiency virus-associated wasting.

Weight loss is commonly associated with increased morbidity and mortality in individuals with human immunodeficiency virus (HIV) infection. We performed a nested case-control study of 26 HIV-infected subjects recruited from a cohort of gay men enrolled in the Multicenter Acquired Immunodeficiency Syndrome Cohort Study. To test the hypothesis that hormonal changes precede and may induce the wasting syndrome, we performed a nested case-control study and analyzed serum gonadal steroids and GH in samples of HIV-infected men with or without weight loss, uncomplicated by diarrhea or ever having an opportunistic infection. We studied 13 cases (mean age +/- SD, 45 +/- 7.2 yr) with a mean weight loss of 13 +/- 3.6%, considered to have the wasting syndrome by Centers for Disease Control criteria (weight loss of > 10%) and 13 controls matched for age and duration of follow-up. Serum bioavailable testosterone (T) levels decreased in the case group (P < 0.05) before the definition of wasting was attained, although weight loss had already begun. More impressive declines occurred in serum T (P = 0.012), free T (P = 0.0025), and bioavailable T (P < 0.0001) during the 6 months immediately before documentation of wasting. These changes were concurrent with an increase in serum FSH (P = 0.0135) without a change in serum LH. We conclude that a decline in bioavailable T occurs early in the course of events leading to wasting, suggesting that changes in gonadal hormones may contribute to the multifactorial etiology of the wasting syndrome.

Adult↗

PubMed1995

Weight loss prior to clinical AIDS as a predictor of survival. Multicenter AIDS Cohort Study Investigators.

In this analysis the aim was to determine the independent effect of moderate to severe weight loss prior to an AIDS diagnosis on survival after AIDS. The study was conducted as part of the Multicenter AIDS Cohort Study (MACS), a longitudinal study of HIV-1-seropositive gay or bisexual men. Measured weight and self-reported weight loss data were collected semiannually from 1984 through 1993. The study population included 962 HIV-1-seropositive men who developed clinical AIDS during the follow-up period. Median survival after AIDS was significantly lower for men with measured weight loss of > or = 4.5 kg 3-9 months and 3-15 months prior to AIDS, or who had lost > 10% of their baseline body weight compared with men with less weight loss or weight gain. Men with self-reported unintentional weight loss of > or = 4.5 kg 3-9 months prior to AIDS had significantly poorer survival (median = 1.05 years vs. 1.48 years; p = 0.0001) compared with men not reporting weight loss. After adjusting for potential confounding factors, men in the high measured weight loss group 3-9 months prior to AIDS still had significantly poorer survival [relative hazard (RH) = 1.36; p = 0.02]. Similar trends were seen for the two longer intervals prior to AIDS (RH = 1.38, p = 0.01; and RH = 1.50, p = 0.02, respectively). Men who self-reported weight loss > or = 4.5 kg 3-9 months prior to AIDS also had significantly poorer survival after AIDS (RH = 1.43; p = 0.002) in multivariate analysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired Immunodeficiency Syndrome↗

PubMed1995

Instability of delayed-type hypersensitivity skin test anergy in human immunodeficiency virus infection.

OBJECTIVE: To evaluate stability of delayed-type hypersensitivity (DTH) skin test over time in human immunodeficiency virus (HIV)-seropositive and HIV-seronegative injecting drug users. METHOD: A community-based cohort of injecting drug users who had serial skin testing with purified protein derivative tuberculin, mumps, and Candida albicans antigen. Delayed-type hypersensitivity anergy was defined as a skin test result of less than 3 mm for all three antigens; DTH positivity was a skin test result of 3 mm or greater for at least one antigen (Centers for Disease Control and Prevention, Atlanta, Ga, 1993). RESULTS: At baseline, 36% of HIV-seropositive subjects (n = 401) were anergic as compared with 14% of HIV-seronegative subjects (n = 552; P < .001). During follow-up, fewer HIV-seropositive subjects remained DTH positive (42%) and more remained anergic (19%) than of HIV-seronegative subjects (67% and 7%, respectively). Twenty-four percent of HIV-seropositive subjects who were initially DTH positive became anergic as compared with 15.3% of the HIV-seronegative subjects. However, the proportion changing from anergy to DTH positivity was greater among HIV-seropositive subjects (15%) than HIV-seronegative subjects (12%). In comparison to those who remained DTH positive, HIV-seropositive subjects with CD4 cell counts of less than 0.50 x 10(9)/L (odds ratio = 6.4) and less than 0.35 x 10(9)/L (odds ratio = 11.2) were more likely to remain anergic than those who had CD4 cell counts above 0.50 x 10(9)/L or were HIV seronegative. CONCLUSIONS: Although the prevalence and incidence of DTH anergy were higher in HIV-seropositive subjects, high rates of change in DTH status occurred in both directions. This suggests that instability of DTH skin testing is substantial and only partially dependent on HIV status. Although a single test may be an unreliable indicator of HIV-induced immunosuppression, two consecutive anergic readings were strongly associated with a CD4 cell count below 0.50 x 10(9)/L and particularly below 0.35 x 10(9)/L. For determining false negativity of tuberculin tests, persistent DTH anergy is more reliable than a single test among HIV-seropositive injecting drug users. Anergy testing appears to be unnecessary with CD4 cell counts greater than 0.5 x 10(9)/L.

Adult↗

PubMed1995

Changes in markers of disease progression in HIV-1 seroconverters: a comparison between cohorts of injecting drug users and homosexual men.

Comparisons of human immunodeficiency virus (HIV) disease progression between risk groups are difficult primarily because of the long incubation period of acquired immune deficiency syndrome (AIDS) and unknown times of infection. This is believed to be the first study that directly compared changes in T-lymphocyte subsets following HIV-1 seroconversion between cohorts of predominantly black injecting drug users and predominantly white homosexual men. Longitudinal trends of CD4 and CD8 percentages of total lymphocytes during 4 years were modeled as piecewise linear functions with a two-parameter correlation structure to accommodate within-person repeated observations. Prior to seroconversion the 151 injecting drug users started with similar CD4% and CD8% levels compared with the 99 homosexual men. Following seroconversion, larger changes were observed overall in the homosexual men compared with the injecting drug users for both markers (p < or = 0.001). The major discrepancies, however, were limited to the first 2 years. Subsequently, the CD4% levels of the two cohorts converged and then declined at similar rates. These comparative analyses of HIV seroconverters in homosexual men and injecting drug users suggest that risk group has only a minor effect on the initial course of HIV infection.

Adult↗

PubMed1995

Prognostic value of combined response markers among human immunodeficiency virus-infected persons: possible aid in the decision to change zidovudine monotherapy.

To clarify useful clinical parameters for determining the need for changes in antiretroviral regimens, 586 persons who were seropositive for the human immunodeficiency virus (HIV) and who had intermediate-stage HIV disease underwent follow-up semiannually for a median of 3.1 years after zidovudine monotherapy was instituted. The strongest predictors of time to the development of AIDS and of survival were an increased CD4 lymphocyte count (> 50/microL), a decreased neopterin level (> 2.4 nmol/L), and no increase in the number of symptoms after 7-12 months of zidovudine therapy. Men who had the best quartile CD4 lymphocyte and neopterin responses and who also had no increase in the number of symptoms were 23 times less likely to die (reflecting a 96% increase in survival) than were men who had the worst responses in these variable categories. After 7-12 months of zidovudine therapy, 5-year survival rates were 63% for men with good responses in all three variable categories, 47%-49% for those with good CD4 lymphocyte responses and good responses in one other variable category, 31% for those with only a good CD4 lymphocyte response, and 0 for those with poor responses in all three variable categories.

Acquired Immunodeficiency Syndrome↗

PubMed1995

An epidemiologic analysis of Mycobacterium avium complex disease in homosexual men infected with human immunodeficiency virus type 1.

Cofactors associated with the Mycobacterium avium complex (MAC) disease and its prognosis in incident cases of AIDS in homosexuals were studied. We compared 51 men in whom MAC disease developed as the initial AIDS-defining illness (termed AIDS illness hereafter); 157 men who had MAC disease subsequent to another AIDS illness; and 884 men who had only non-MAC AIDS illnesses. MAC disease was the initially diagnosed AIDS illness more often in Baltimore (6.9%) and Los Angeles (5.6%) than in Chicago (2.6%) and Pittsburgh (0) (P < .01). MAC disease also was a more common subsequent AIDS illness in Baltimore (14.3%) and Los Angeles (22.4%) than in Chicago (8.5%) and Pittsburgh (6.5%) (P < .0001). Prophylaxis for Pneumocystis carinii infection increased the occurrence of MAC disease as the initial AIDS illness (from 2.3% to 12.5%; P < .0001). A low white blood cell (WBC) count was slightly more predictive of MAC disease than was a low CD4+ cell count. At 0-6, 7-12, and 13-18 months before diagnosis, the WBC cell counts of 75.0%, 61.1%, and 50.0%, respectively, of those with MAC disease as the initial AIDS illness were < or = 3,400/microL. Men in whom cytomegalovirus disease developed were at higher risk for subsequent MAC disease (relative hazard = 2.65; P < .0001). MAC disease also increased the risk for subsequent cytomegalovirus disease (relative hazard = 3.96; P < .0001).

AIDS-Related Opportunistic Infections↗

PubMed1995

Factors associated with changes in the use of antiretroviral therapy by a cohort of homosexual men infected with human immunodeficiency virus type 1.

Changes in the use of antiretroviral drugs and factors associated with changes from monotherapy with zidovudine (ZDV) to other regimens were quantified in the Multicenter AIDS Cohort Study. Participants who had been receiving monotherapy with ZDV were categorized as (1) discontinuing ZDV monotherapy; (2) switching to disanosine (ddI), zalcitabine (ddC), or stavudine (d4T) monotherapy; (3) switching to combination therapy (ZDV with ddI, ddC, or d4T); or (4) continuing ZDV monotherapy. From 1990 to 1994, the percentage of participants using ZDV monotherapy decreased from 27% to 17% (among participants without AIDS) and from 60% to 17% (among those with AIDS). At the same time, the proportion of participants using combination therapy increased from zero to 8% (no AIDS) and from 8% to 26% (AIDS). Polychotomous logistic regression methods were used to identify the factors predicting changes from ZDV monotherapy. Among participants without AIDS, indicators of drug failure (such as a lower CD4 lymphocyte count or symptoms of human immunodeficiency virus type 1 infection) were predictive of the initiation of combination therapy, while among patients with AIDS they were predictive of a switch to an alternative monotherapy. A decrease in hemoglobin levels, a marker of ZDV toxicity, was predictive for all patients of a switch to other monotherapy. These data show that clinicians and patients are opting for more aggressive antiretroviral regiments and that changes in CD4 lymphocyte count and in the status of symptoms remain the primary guides for changes in therapy.

Antiviral Agents↗

PubMed1995

High rate of transmission of tuberculosis in an office: impact of delayed diagnosis.

We identified two cases of tuberculosis (TB) in office co-workers in Melbourne, Victoria, Australia; the Mycobacterium tuberculosis isolates were found to be identical with use of restriction fragment length polymorphism. Contact tracing was performed for 195 of 210 workers by means of the tuberculin skin test. Risk of infection was assessed according to a number of variables. Office contacts were exposed to infectious TB for 4 months; at least 24% of employees were infected. There was an association between sitting in proximity to the case during the period of exposure (OR, 4.24; 95% CI, 1.06-19.67). On-site workers had a higher risk of being infected (OR, 5.48; CI, 1.51-23.54) than did visiting workers. Workers in this office were exposed to open pulmonary TB for prolonged periods. The prevalence of TB infection (24%) among these workers was high compared with the infection rate (2%-7%) in the general community. Delay in diagnosis was the major factor responsible for the spread of TB in this office.

Adult↗

PubMed1995

Vitamin A deficiency and wasting as predictors of mortality in human immunodeficiency virus-infected injection drug users.

A nested case-control study of vitamin A deficiency and wasting as risk factors for mortality from AIDS and infections was done within a large prospective cohort of human immunodeficiency virus (HIV)-infected injection drug users (IDUs). Fifty adult subjects who died from AIDS and infections were matched with 235 controls who survived. Plasma vitamin A, weight, and body mass index were measured. Mean length of follow-up was 2.4 +/- 1.1 years. Vitamin A deficiency occurred in 50% and wasting occurred in 38% of patients in the last visit before death. CD4 cells count < 200/microL, wasting, and vitamin A deficiency were associated with mortality. There was a higher risk of death in HIV-infected subjects with vitamin A deficiency (odds ratio [OR], 4.6; 95% confidence interval [CI], 1.8-11.3) and wasting (OR, 8.8; 95% CI, 2.7-28.2). Vitamin A deficiency and wasting are common during HIV infection and are independent predictors of mortality in HIV-infected IDUs.

Acquired Immunodeficiency Syndrome↗

PubMed1995

Age, gender, and other predictors of the wasting syndrome among HIV-1-infected injecting drug users.

We conducted a study to identify predictors of the wasting syndrome among human immunodeficiency virus 1 (HIV-1)-seropositive injecting drug users. We enrolled 113 cases (defined as an unexplained loss of > 10% baseline weight) and 226 controls (defined as < 5% weight loss or any weight gain) from a HIV-1-seropositive cohort of injecting drug users (N = 630) into a nested case-control study. Crude predictors of wasting included: older age [odds ratio (OR) for a 1-year difference = 1.06], female gender (OR = 1.66), more years spent injecting drugs (OR for 1-year difference = 1.05), presence of diarrhea (OR = 3.78), lower percentage of CD4 T-lymphocytes (OR for 10-unit difference = 0.73), and higher log beta 2-microglobulin concentration (OR for 1 log difference = 11.3). After adjusting for CD4 cell level, beta 2-microglobulin concentration, diarrhea, gender, length and frequency of drug use, age, the presence of thrush, and education, independent predictors of weight loss in HIV-seropositive injecting drug users were female gender (OR = 2.23) and increasing age (OR for 1-year difference = 1.06). Frequency and duration of drug use were not strongly associated with the odds of developing wasting syndrome in this HIV-1-seropositive cohort. These data indicate that HIV wasting syndrome in injecting drug users is distinct from complications of drug use.

Adult↗

PubMed1995

Interaction of socioeconomic status and provider practices as predictors of immunization coverage in Virginia children.

OBJECTIVE: To describe the pattern of immunization in the cohort of children who entered public schools in Virginia in 1992. DESIGN: This was a historic cohort study using stratified cluster sampling. Three strata were created based on the socioeconomic status (SES) of the children in the catchment area of each public school in Virginia. SETTING: The random sample included public elementary schools throughout Virginia. PARTICIPANTS: Immunization records were obtained for a randomly selected cohort of 2519 first-grade children in Virginia. OUTCOME MEASURES: Age at completion of recommended childhood vaccines was determined from birth to school entry by SES, race, and population density. Provider practices were assessed by ascertaining missed opportunities for simultaneous administration of vaccinations according to recommended schedules. RESULTS: Although immunization completion rates were high at school entry, low levels of immunization coverage were found in all areas of Virginia at 24 months of age regardless of SES (as measured by per capita income), population density, or race. However, under-immunization was more severe for poor children in urban areas (42.3% of children in low-SES urban areas were age-appropriately immunized at 24 months of age versus 64.0% in children in high-SES rural areas). By multivariate logistic regression, race and gender were not predictors of which children were appropriately immunized at 2 years of age after adjusting for the following: SES, population density, receiving the first DTP (diphtheria, tetanus, and pertussis) or OPV (oral polio) vaccination after 3 months of age, and failure to have the first DTP administered simultaneously with the first OPV or the second DTP administered simultaneously with the second OPV. Receiving the first DTP or OPV vaccination after 3 months of age and failure to have the first and second DTP and OPV administered simultaneously were the strongest predictors of not being age-appropriately immunized at 2 years of age. The effect of failure to vaccinate simultaneously on predicting vaccination coverage at 2 years of age was strongly modified by SES. Children who attended schools located in census tracts with per capita incomes less than $10,600 and who did not have the first and second doses of DTP and OPV administered simultaneously were 33.19 times more likely not to be age-appropriately immunized at 2 years of age compared with children who attended schools located in census tracts with per capita incomes greater than $18,800 and who received the first and second doses of DTP and OPV simultaneously (95% confidence interval: 18.29 to 60.22). CONCLUSIONS: Although beginning the immunization schedule at the recommended age was crucial to appropriate vaccination later in life, provider practices were important predictors of under-immunization. Failure to administer vaccinations simultaneously strongly influenced poorer children in Virginia. Serious delays in vaccine administration were observed not only for poor children in urban areas, but also in all areas of Virginia before school entry.

Child↗

PubMed1995

Long-term survival without clinical AIDS after CD4+ cell counts fall below 200 x 10(6)/l.

OBJECTIVE: Quantify and study cofactors of long-term survival without AIDS in HIV-1-infected individuals with CD4+ cell counts < 200 x 10(6)/l. DESIGN: Comparison of 579 participants who could be longitudinally evaluated for at least 3 years after the earliest date of first reaching a CD4+ cell count < 200 x 10(6)/l or an AIDS-defining illness (1987 Centers for Disease Control and Prevention definition). SETTING: Ongoing 9-year cohort study with data collected at 6-month intervals. PATIENTS: HIV-1-infected homosexual men. MEASUREMENTS AND MAIN RESULTS: Of the men, 20% did not develop an AIDS illness within 3 years following a confirmed CD4+ cell count < 200 x 10(6)/l; 29 and 28% were diagnosed with a first clinical AIDS illness from 1-3 and < 1 years, respectively, beyond their first CD4+ cell count < 200 x 10(6)/l; 23% were diagnosed with a clinical AIDS illness prior to their first CD4+ cell count < 200 x 10(6)/l. Slower decline of CD4+ cell count (P < 0.001) and presence of higher body-mass index during the period prior to the first CD4+ cell count < 200 x 10(6)/l (P < 0.001) predicted longer time to an AIDS illness once this threshold was reached. Most men had rapid loss of CD4+ cells, total T cells, and hemoglobin during the period after CD4+ cells declined below 200 x 10(6)/l. However, those remaining free of AIDS illnesses the longest arrested their decline in CD4+ cell counts and hemoglobin levels and increased total T cells during this period. Although antiretroviral therapy and Pneumocystis carinii prophylaxis extend AIDS-free survival, 45% of the group who were AIDS-free > or = 3 years after CD4+ cells fell below 200 x 10(6)/l had not used these treatments. CONCLUSIONS: Significant numbers of individuals remain free of illnesses and AIDS symptoms > or = 3 years after CD4+ cell counts drop below 200 x 10(6)/l. This occurs even in the absence of treatment. The associations seen here suggest that host and viral factors play important roles. Thus, further studies are needed to determine the biological basis of long-term survival without AIDS illnesses in HIV-1-immunosuppressed patients.

Acquired Immunodeficiency Syndrome↗

PubMed1994

The effect of the interaction of acyclovir with zidovudine on progression to AIDS and survival. Analysis of data in the Multicenter AIDS Cohort Study.

OBJECTIVE: To examine the effect of acyclovir use on disease progression and survival in human immunodeficiency virus (HIV)-seropositive persons treated with zidovudine. SETTING: Four university-based or -affiliated clinics. DESIGN: Prospective cohort study of homosexual and bisexual men with semi-annual follow-up. Intent-to-treat Cox models were fit to determine the relation between the use of acyclovir (modeled as a time-dependent covariate) and disease progression, controlling for baseline and time-dependent clinical and laboratory prognostic variables. The acquired immunodeficiency syndrome (AIDS)-free duration and survival time were calculated from the first use of zidovudine. Analysis included study visits 7 to 17 (from 1987 to 1992). PATIENTS: 786 HIV-seropositive participants in the Multicenter AIDS Cohort Study who began zidovudine therapy before a clinical diagnosis of AIDS; of these, 515 subsequently received acyclovir. Participants were asked at each visit whether they had "used any medication for health reasons not related to AIDS or if they had taken any medication to help fight AIDS or the HIV virus"; 488 patients indicated acyclovir use under either or both questions, and 242 patients indicated only the latter use. RESULTS: The use of acyclovir for any indication was not associated with an effect on progression to AIDS but was associated with a 26% decrease in the risk for death (relative hazard, 0.74; P = 0.07). The use of acyclovir for HIV infection was also not associated with an effect on progression to AIDS but was associated with a 36% decrease in the risk for death (relative hazard, 0.64; P = 0.01). To further investigate these findings, we examined dose, constancy, and timing of acyclovir use. The median daily dose of acyclovir used for HIV infection was between 600 and 800 mg. No apparent dose effect on survival was found. Longer uninterrupted use of acyclovir for any indication was associated with an 18% decrease in the risk for death for three or more consecutive visits (relative hazard, 0.82; P = 0.23), a 28% decrease for four or more consecutive visits (relative hazard, 0.72; P = 0.09), and a 7% decrease per visit based on the cumulative number of visits while the patient received acyclovir (relative hazard, 0.93 per visit increase; P = 0.03). Use of acyclovir for any indication and use of acyclovir for HIV infection were each associated with a 44% decreased probability of death if the drug was used after AIDS developed (P = 0.007 and P = 0.005, respectively) but not before. To further investigate the prolongation of survival, two landmark analyses were done. The first analysis began at a landmark of 1 year after initiation of zidovudine therapy and compared three groups of patients: those who used acyclovir at or before this landmark, those who had never started acyclovir or started the drug after the landmark, and those who had never used acyclovir. The 90% survival times were 1325, 1059, and 982 days, respectively. The second analysis began at a landmark of developing either a CD4 count less than 50 cells/microL or clinical AIDS. The 90% survival times for the three groups were 398, 261, and 176 days, respectively. CONCLUSIONS: Our analysis suggests that consistent use of acyclovir at a dose sufficient to suppress herpetic recurrences (that is, 600 to 800 mg/d) has a clinically significant effect on prolonging survival in a well-characterized cohort with extensive previous exposure to herpesvirus infections. Further clinical investigation of low-dose acyclovir with concomitant antiretroviral therapy is warranted.

Acquired Immunodeficiency Syndrome↗

PubMed1994

Concorde trial of immediate versus deferred zidovudine.

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Acquired Immunodeficiency Syndrome↗

PubMed1994

Immunization coverage in a population-based sample of Maryland children.

OBJECTIVE: To describe the vaccination coverage of a population-based sample of Maryland children. DESIGN: Historical cohort study using stratified cluster sampling. Strata were formed from five state regions and public and private schools within each region. SETTING: Random sample of elementary schools in Maryland. SUBJECTS: Immunization records were obtained for a randomly selected cohort of 1938 first-grade children in Maryland. OUTCOME MEASURES: Age of completion of recommended childhood vaccines and proportion of vaccines given simultaneously. RESULTS: By first grade, 95.2% of the sample of Maryland children were documented to have received at least four doses of the diphtheria and tetanus toxoids and pertussis (DTP) vaccine, three doses of oral poliovirus (OPV) vaccine, and one dose of measles-mumps-rubella (MMR) vaccine. However, only 54.8% of children surveyed had achieved this level of immunization by 24 months of age. For children whose immunizations were up to date on their first birthday (78.7% of children surveyed), vaccine providers failed to administer one dose of DTP, OPV, and MMR vaccines to 30% of these children during the second year of life. Only 16.2% (n = 313) of children sampled received an MMR vaccination simultaneously with any dose of DTP or OPV vaccine. CONCLUSIONS: This study shows that while immunization levels are very high at school entry, there are serious delays in vaccine administration before school entry. These delays are observed regardless of whether children are in public or private schools or attend school in an urban, suburban, or rural area. Physicians and health care providers could play an important role in age-appropriate vaccination by administering vaccines simultaneously.

Child↗

PubMed1994

Comparison of self-reported injection frequencies for past 30 days and 6 months among intravenous drug users.

In this study we compared two parallel self-reported measures that now are being used to assess the recent frequency of intravenous drug use. This study sample consisted of 926 HIV seronegative drug users recruited for participation in HIV research. During a standard interview with each drug user, we first asked about injections in the past 30 days, and then about injections in the past 6 months. The correlation between reports on the past 6 months and the past 30 days was appreciable when all injections were considered (Spearman correlation coefficient rho = 0.78). It increased when the sample was restricted to subjects who reported injections in the past month (rho = 0.88). This restriction resulted in a 15% reduction of the sample size, since 137 participants reported drug use in the previous 6 months but not in the previous 30 days. Concordance tended to be slightly higher for reported frequencies of heroin injections than for cocaine injections, and for men as compared to women. The observed levels of concordance indicate that in many instances both approaches can yield comparable results. Nevertheless the choice of 30 days recall vs 6 months recall must rest upon the specific research questions of each investigation.

Adult↗

PubMed1994

Access to therapy in the Multicenter AIDS Cohort Study, 1989-1992.

The study aims were (i) to describe secular trends in the utilization of antiretrovirals, antivirals, Pneumocystis carinii pneumonia (PCP) prophylaxis, and antifungal prophylaxis and (ii) to determine whether factors such as clinical status, health services utilization, insurance status, income, education and race were associated with access to therapy. Data on utilization of therapy, health services utilization, income and insurance status were collected semiannually from October 1990 through March 1992 from 1415 homosexual/bisexual HIV-1 seropositive men in the Multicenter AIDS Cohort Study (MACS). Prevalence of therapy use according to level of immunosuppression was determined at each study visit. Clinical AIDS was defined using the 1987 CDC definition. Factors associated with use of antiretroviral therapy and PCP prophylaxis were assessed using multiple logistic regression with robust variance techniques to adjust variance estimates and significance levels for within-person correlations of drug use over time. Prevalence of zidovudine use remained relatively constant throughout the study period. In contrast, use of didanosine (21-34%), acyclovir (23-34%) and dideoxycytidine (zalcitabine) (8-25%) increased in participants with clinical AIDS. Similar trends were seen for combination antiretroviral therapy, trimethoprim-sulfamethoxazole, dapsone, ketoconazole and fluconazole. However, reported use of aerosolized pentamidine fell. After adjusting for CD4+ lymphocyte count and HIV-1 symptoms, previous HIV-related hospitalization (OR = 1.52; 95% CI = 1.22-1.91), outpatient visit (OR = 2.83; 95% CI = 2.12-3.78), having insurance (OR = 1.32; 95% CI = 1.01-1.75), college education (OR = 1.42; 95% CI = 1.13-1.80) and white race (OR = 1.58; 95% CI = 1.21-2.07) were all associated with being on antiretroviral therapy in persons without clinical AIDS. In persons with clinical AIDS, having insurance (OR = 2.89; 95% CI = 1.04-8.02) and a previous outpatient visit (OR = 11.69; 95% CI = 1.77-77.30) were the significant variables. Factors significantly associated with being on PCP prophylaxis in multivariate models were previous hospitalization, previous outpatient visit, and college education (for subjects without clinical AIDS.

Acquired Immunodeficiency Syndrome↗