Judicial gatekeeping and the social construction of the admissibility of expert testimony.

Content analysis of 192 U.S. District Court cases was conducted to investigate judges' evaluations of expert characteristics and evidence characteristics for toxicology, psychological/psychiatric, and damages testimony. Judges evaluated more expert characteristics, but not more evidence characteristics, as the number of months post-Daubert increased (Hypotheses 1 and 2). More evidence characteristics were evaluated when evidence was quantitatively rather than qualitatively based (Hypothesis 3). The greatest number of evidence characteristics examined was for toxicology evidence (Hypothesis 4). Fewer expert characteristics were evaluated for admissible evidence, but more evidence characteristics were evaluated for inadmissible evidence (Hypothesis 5). All analyses were significant at .05. Implications for judges, attorneys, and experts are discussed.

Retention in care within 1 year of initial HIV care visit in a multisite US cohort: who's in and who's out?

Biannual attendance at medical visits is an established measure of retention in HIV care. We examined factors associated with attending at least 2 clinic visits at least 90 days apart among HIV-infected, antiretroviral therapy (ART)-naive HIV Outpatient Study participants entering care during 2000 to 2011. Of 1441 patients, 85% were retained in care during the first year of observation. Starting ART during the year was the strongest correlate of retention (adjusted odds ratio [aOR] 6.4, 95% confidence interval [CI] 4.4-9.4). After adjusting for starting ART, publicly insured patients (aOR 0.6, 95% CI 0.4-1.0), and patients with baseline CD4 counts <200 cells/mm(3) (aOR 0.5, 95% CI 0.3-0.9) or missing CD4 counts (aOR 0.3, 95% CI 0.2-0.6) were less likely to be retained in care. Although most patients had recommended biannual care visits, some ART-naive individuals may require additional interventions to remain in care. Promptly initiating ART may facilitate engagement in care.

Immune reconstitution inflammatory syndrome: incidence and implications for mortality.

OBJECTIVE: To describe incidence of immune reconstitution inflammatory syndrome (IRIS) and its association with mortality in a large multisite US HIV-infected cohort applying an objective, comprehensive definition. DESIGN: We studied 2,610 patients seen during 1996-2007 who initiated or resumed highly active combination antiretroviral therapy (cART) and, during the next 6 months, demonstrated a decline in plasma HIV-RNA viral load of at least 0.5 log(10) copies/ml or an increase of at least 50% in CD4 cell count per microliter. We defined IRIS as the diagnosis of a type B or C condition [as per the Centers for Disease Control and Prevention (CDC) 1993 AIDS case definition] or any new mucocutaneous disorder during this same 6-month period. METHODS: We assessed the incidence of IRIS and evaluated risk factors for IRIS using conditional logistic regression and for all-cause mortality using proportional hazards models. RESULTS: We identified 370 cases of IRIS (in 276 patients). Median and nadir CD4 cell counts at cART initiation were 90 and 43 cells/µl, respectively; median viral load was 2.7 log(10) copies/ml. The most common IRIS-defining diagnoses were candidiasis (all forms), cytomegalovirus infection, disseminated Mycobacterium avium intracellulare, Pneumocystis pneumonia, varicella zoster, Kaposi's sarcoma and non-Hodgkin lymphoma. Only one case of Mycobacterium tuberculosis was observed. IRIS was independently associated with CD4 cell count less than 50 cells/µl vs. at least 200 cells/µl [odds ratio (OR) 5.0] and a viral load of at least 5.0 log(10) copies vs. less than 4.0 log(10) copies (OR 2.3). IRIS with a type B-defining or type C-defining diagnosis approximately doubled the risk for all-cause mortality. CONCLUSION: In this large US-based HIV-infected cohort, IRIS occurred in 10.6% of patients who responded to effective ART and contributed to increased mortality.

Trends in the Treatment of Anemia Using Recombinant Human Erythropoietin in Patients with HIV Infection.

BACKGROUND: Treating anemia with erythropoietin (EPO) to hemoglobin (Hb) endpoints >11 g/dL may increase risk of serious adverse cardiovascular events. METHODS: We used medical records data (1996-2003 from the Adolescent Spectrum of HIV Disease Project [ASD] and 1996-2006 from the HIV Outpatient Study [HOPS]) to describe EPO prescription patterns for mildly, moderately, or severely anemic HIV-infected patients. We calculated proportions prescribed EPO and treated to Hb>12 g/dL, and tested for trends over time. We calculated median hemoglobin at first EPO prescription, and described temporal changes using linear regression. RESULTS: Among 37,395 patients in ASD and 7,005 patients in HOPS, EPO prescription increased over time for moderately anemic patients; for patients with severe anemia, EPO prescription increased only among ASD patients. Hb at EPO prescription decreased over time in ASD patients (median=8.5 g/dL), but not in HOPS patients (median 9.5 g/dL). Percentage of EPO-treated patients with post-treatment Hb>12 g/dL was 18.3% in ASD and stable, and was 56.7% in HOPS and increased over time (p = 0.03). CONCLUSIONS: Through 2006, EPO prescription increased over time for patients with moderate or severe anemia. Many patients treated with EPO had post-treatment Hb>12 g/dL. Based on 2011 FDA recommendations, changes in previous prescription practices will be needed.

Trends in hepatitis C virus infection among patients in the HIV Outpatient Study, 1996-2007.

BACKGROUND: Coinfection with hepatitis C virus (HCV) contributes increasingly to the morbidity and mortality of persons infected with HIV. We assessed HCV infection screening practices and determined trends in the prevalence of HCV infection in the HIV Outpatient Study (HOPS) from 1996 to 2007. METHODS: We calculated the proportion of patients eligible to be tested for HCV infection (i.e., never tested or previously tested negative) and the prevalence of HCV infection annually from 1996 to 2007 by sociodemographic, clinical, and HIV risk category characteristics. We used multiple logistic regression analyses to evaluate factors independently associated with HCV testing. RESULTS: A total of 7618 patients were active in the HOPS from 1996 through 2007. The proportion of eligible patients tested for HCV infection increased from 10.7% in 1996 to 76.6% in 2007 and increased among all demographic and risk groups. Overall HCV prevalence decreased from 36.7% in 1996 to 19.7% in 2007; decreases in prevalence occurred among all groups except for injection drug users (IDUs). In multivariable analysis, age older than 35 years, nonwhite race, Hispanic ethnicity, high-risk heterosexual and IDU risk categories, and at least 3 years of enrollment in the HOPS were associated with increased odds of having been tested for HCV infection. CONCLUSIONS: Screening for HCV infection in the HOPS has improved, although a sizable fraction of patients remain unscreened. The decline in overall HCV infection prevalence from 1996 to 2007 resulted primarily from a decline in the fraction of all prevalent infections in the cohort attributable to IDU patients.

Rates of hospitalizations and associated diagnoses in a large multisite cohort of HIV patients in the United States, 1994-2005.

OBJECTIVES: To assess temporal trends in the rates of hospitalizations and associated diagnoses among HIV-infected patients before and during the era of highly active antiretroviral therapy. DESIGN: A prospective cohort study of 7155 patients enrolled in the HIV Outpatient Study at 10 US HIV clinics. METHODS: We evaluated rates of hospitalizations for major categories of medical conditions during 1994-2005 and modeled trends in these rates using multivariable Poisson regression models for repeated observations. We assessed patient characteristics associated with hospitalization using multiple logistic regression. RESULTS: The rates of hospitalizations (per 100 person-years) fell from 24.6 in 1994 to 11.8 in 2005 (P < 0.0001). The rates of hospitalizations for AIDS opportunistic infections decreased from 7.6 in 1994-1996 to 1.0 in 2003-2005 (P < 0.0001). AIDS opportunistic infections were present at 31% of hospitalizations in 1994-1996 versus 9.5% in 2003-2005, and chronic end-organ disease conditions were present at 7.2% of such hospitalizations in 1994-1996 versus 14.3% in 2003-2005. Mean CD4+ cell count at hospitalization increased from 115 cells/mul in 1994 to 310 cells/mul in 2005. Factors independently associated with hospitalization in the highly active antiretroviral therapy era (1997-2005) included older age, history of substance abuse, lower CD4+ cell count, history of AIDS, and public health insurance. CONCLUSION: The rates of hospitalizations for HIV-infected patients declined substantially during 1994-2005, due mainly to reductions in the AIDS opportunistic infections. Compared with the period 1994-1997, patients in the highly active antiretroviral therapy era were hospitalized with higher CD4+ cell counts and more frequently for chronic end-organ conditions.

Increased body mass index does not alter response to initial highly active antiretroviral therapy in HIV-1-infected patients.

BACKGROUND: Body mass index (BMI) can influence drug metabolism, thus affecting efficacy and risk for toxicities. Hypothesizing that persons with an increased BMI and larger volumes of distribution may experience a suboptimal response to highly active antiretroviral therapy (HAART), we evaluated the effect of BMI on virologic and immunologic response in previously ART-naive patients initiating therapy. METHODS: Using data from the HIV Outpatient Study, we analyzed the statistical association of BMI and other selected demographic variables with achieving an undetectable viral load and experiencing a CD4 cell count increase of more than 100 cell/microL after 3 to 9 months of therapy among antiretroviral-naive patients initiating HAART. RESULTS: Among 711 patients included in analysis, 43% had a BMI of more than 25 (overweight-obese). Higher BMI was associated with being female, having black or Hispanic race/ethnicity, being heterosexual, and using injection drugs (all P<0.001). The patients in BMI groups did not differ significantly by baseline CD4 cell count or the duration of the initial HAART regimen. Although median baseline viral loads were significantly lower in obese participants (P=0.008), overweight or obese BMI did not significantly alter the likelihood of achieving an undetectable viral load and a CD4 cell count increase of more than 100 cells/microL compared with normal weight persons. CONCLUSION: A substantial proportion of HIV-infected outpatients in this cohort were overweight or obese. Increased BMI was not associated with decreased virologic and immunologic responses to initial HAART. Responses were equivalent and within expected ranges between normal weight patients, overweight patients, and obese patients at 3 to 9 months of observation.