Evaluation of disparity in care for perforated appendicitis in a universal healthcare system.

Purpose: Racial and socioeconomic disparities have been reported in the management of appendicitis. Perforated appendicitis (PA) is used as an index for barriers to care due to delays in treatment. This study evaluates the effect of racial and socioeconomic differences on the likelihood of PA in a universally insured national healthcare system.

Virologic, immunologic and clinical responses in foreign-born versus US-born HIV-1 infected adults initiating antiretroviral therapy: an observational cohort study.

Introduction: Mortality rates within the first year of combination antiretroviral therapy (cART) initiation are several-fold higher in resource-limited countries than in resource-replete settings. However studies in western countries examining virologic, immunologic and clinical responses after cART initiation in indigenous versus non-indigenous populations have shown mixed results. This study aimed to determine whether there is a difference in these outcomes in a United States setting between foreign-born and US-born patients.

Chronic kidney disease at presentation is not an independent risk factor for AIDS-defining events or death in HIV-infected persons.

Studies have documented an association between chronic kidney disease (CKD) and increased risk of end stage renal disease, death and comorbidities, including cardiovascular disease and metabolic syndrome, in the general population. However, there is little data on the relationship between CKD and ADE (AIDS defining event), and to our knowledge, no studies have analyzed death as a competing risk for ADE among HIV-infected persons. An observational cohort study was performed to determine the incidence and risks for developing an ADE or death among HIV-infected persons with and without CKD from 1998 - 2005.

Hemoglobin may contribute to sex differences in mortality among HIV-infected persons in care.

Background: Some retrospective studies have found that HIV-infected women have a higher mortality risk than men after adjusting for baseline characteristics, while others have not. Anemia is a known predictor of HIV-related mortality. We assessed whether anemia contributed to the sex difference in mortality in our cohort.

Active cocaine use is associated with lack of HIV-1 virologic suppression independent of nonadherence to antiretroviral therapy: use of a rapid screening tool during routine clinic visits.

Clarifying the relationship between illicit drug use and HIV-1 virologic suppression requires characterization of both illicit drug use activity and adherence to antiretroviral therapy (ART). We developed a rapid clinical questionnaire to assess prior 7-day illicit drug use and ART adherence in a cross-sectional study among 1777 HIV-infected persons in care. Of these, 76% were male, 35% were African-American, and 8% reported injection drug use as their probable route of HIV-1 infection.

An optimal body mass index range associated with improved immune reconstitution among HIV-infected adults initiating antiretroviral therapy.

Background: Higher body mass index (BMI) was associated with slower human immunodeficiency virus (HIV) disease progression before the availability of effective antiretroviral therapy (ART), but the relationship between pretreatment BMI and CD4(+) lymphocyte recovery on ART is not well described.

Methods: We conducted an observational cohort study of HIV-infected, ART-naive adults starting treatment at a clinic affiliated with Vanderbilt University in Nashville, Tennessee. We assessed the relationship between pretreatment BMI and CD4(+) lymphocyte count change from baseline to 12 months in all subjects, among those with plasma HIV-1 RNA levels <400 copies/mL for ≥ 6 months and those with <10% change in weight during follow-up.

Non-AIDS-defining events among HIV-1-infected adults receiving combination antiretroviral therapy in resource-replete versus resource-limited urban setting.

Objective: To compare incidence and distribution of non-AIDS-defining events (NADEs) among HIV-1-infected adults receiving combination antiretroviral therapy (cART) in urban sub-Saharan African versus United States settings.

Design: Retrospective cohort analysis of clinical trial and observational data.

Methods: Compared crude and standardized (to US cohort by age and sex) NADE rates from two urban adult HIV-infected cART-initiating populations: a clinical trial cohort in Gaborone, Botswana (Botswana) and an observational cohort in Nashville, Tennessee (USA).

Drug use and receipt of highly active antiretroviral therapy among HIV-infected persons in two U.S. clinic cohorts.

Objective: Drug use and receipt of highly active antiretroviral therapy (HAART) were assessed in HIV-infected persons from the Comprehensive Care Center (CCC; Nashville, TN) and Johns Hopkins University HIV Clinic (JHU; Baltimore, MD) between 1999 and 2005.

Methods: Participants with and without injection drug use (IDU) history in the CCC and JHU cohorts were evaluated. Additional analysis of persons with history of IDU, non-injection drug use (NIDU), and no drug use from CCC were performed.

Tuberculosis risk before and after highly active antiretroviral therapy initiation: does HAART increase the short-term TB risk in a low incidence TB setting?

Objective: To evaluate the short-term and long-term effects of highly active antiretroviral therapy (HAART) on tuberculosis (TB) risk compared with risk without HAART in a low TB incidence setting.

Design: An observational cohort study among HIV-infected persons in care at the Comprehensive Care Center (Nashville, TN) between January 1998 and December 2008.

Methods: A marginal structural model was used to estimate the effect of HAART on short-term (≤180 days) and long-term (>180 days) TB risk, with CD4⁺ lymphocyte count incorporated as a time-updated covariate.

The relationship between injection and noninjection drug use and HIV disease progression.

Background: Injection drug use is associated with poor HIV outcomes even among persons receiving highly active antiretroviral therapy (HAART), but there are limited data on the relationship between noninjection drug use and HIV disease progression.

Methods: We conducted an observational study of HIV-infected persons entering care between January 1, 1999, and December 31, 2004, with follow-up through December 31, 2005.

Results: There were 1,712 persons in the study cohort: 262 with a history of injection drug use, 785 with a history of noninjection drug use, and 665 with no history of drug use; 56% were White, and 24% were females.

Race, kidney disease progression, and mortality risk in HIV-infected persons.

Background And Objectives: The burden of HIV-associated chronic kidney disease (CKD) is growing in the United States, partially because of increased HIV-infection rates among African Americans. We determined the prevalence, incidence, and risk of rapid estimated GFR (eGFR) decline, ESRD, and death among HIV-infected (HIV+) African-American and non-African-American individuals cared for at the Comprehensive Care Center in Nashville, Tennessee, from January 1, 1998, through December 31, 2005.

Design, Setting, Participants, & Measurements: Mixed effects, competing risks, and Poisson and Cox regression models were used to assess the risk of rapid eGFR decline (defined as ≥50% decrease in baseline eGFR), CKD5/ESRD, and death.

Estimating the optimal CD4 count for HIV-infected persons to start antiretroviral therapy.

Background: Optimal timing of antiretroviral therapy in HIV-infected persons is unclear, although 2 recent large observational studies have improved our understanding of the best CD4 threshold for initiation. These studies compared the effect of starting HAART on mortality and mortality/AIDS between strata defined using broad ranges of CD4 counts. We sought to expand this understanding using a novel statistical approach proposed by Robins et al.

Postpartum discontinuation of antiretroviral therapy and risk of maternal AIDS-defining events, non-AIDS-defining events, and mortality among a cohort of HIV-1-infected women in the United States.

This retrospective cohort study of HIV-infected women receiving highly active antiretroviral therapy (HAART) while pregnant assessed the effect of postpartum HAART discontinuation on maternal AIDS-defining events (ADEs), non-AIDS-defining events (non-ADEs), and death 1997-2008 in Nashville, Tennessee. Cox proportional hazards models compared rates of ADE or all-cause death and non-ADE or all-cause death, and competing risks analyses compared rates of ADE or ADE-related death and non-ADE or non-ADE-related death across the groups. There were two groups: women who stopped HAART postpartum (discontinuation, n = 54) and women who continued HAART postpartum (continuation, n = 69).

Antiretroviral therapy initiation before, during, or after pregnancy in HIV-1-infected women: maternal virologic, immunologic, and clinical response.

Background: Pregnancy has been associated with a decreased risk of HIV disease progression in the highly active antiretroviral therapy (HAART) era. The effect of timing of HAART initiation relative to pregnancy on maternal virologic, immunologic and clinical outcomes has not been assessed.

Methods: We conducted a retrospective cohort study from 1997-2005 among 112 pregnant HIV-infected women who started HAART before (N = 12), during (N = 70) or after pregnancy (N = 30).

Race and sex differences in antiretroviral therapy use and mortality among HIV-infected persons in care.

Background: There are conflicting data regarding race, sex, and mortality among persons infected with human immunodeficiency virus (HIV). We studied all-cause mortality among persons in care during the highly-active antiretroviral therapy (HAART) era.

Methods: This retrospective cohort study included patients who made>or=1 clinic visit from January 1998 through December 2005.

Increased detectability of plasma HIV-1 RNA after introduction of a new assay and altered specimen-processing procedures.

After changes to assay and specimen-processing methods, plasma human immunodeficiency virus type 1 (HIV-1) RNA was frequently detectable in patients who previously had well-suppressed HIV-1 RNA levels. This artifact is attributable to shipping frozen plasma in primary plasma preparation tubes and is not caused by the HIV-1 RNA detection assay; it can be avoided by shipping plasma in a secondary tube.