Competing risk regression models for epidemiologic data

Competing events can preclude the event of interest from occurring in epidemiologic data and can be analyzed by using extensions of survival analysis methods. In this paper, the authors outline 3 regression approaches for estimating 2 key quantities in competing risks analysis: the cause-specific relative hazard ((cs)RH) and the subdistribution relative hazard ((sd)RH). They compare and contrast the structure of the risk sets and the interpretation of parameters obtained with these methods. They also demonstrate the use of these methods with data from the Women's Interagency HIV Study established in 1993, treating time to initiation of highly active antiretroviral therapy or to clinical disease progression as competing events. In our example, women with an injection drug use history were less likely than those without a history of injection drug use to initiate therapy prior to progression to acquired immunodeficiency syndrome or death by both measures of association ((cs)RH = 0.67, 95% confidence interval: 0.57, 0.80 and (sd)RH = 0.60, 95% confidence interval: 0.50, 0.71). Moreover, the relative hazards for disease progression prior to treatment were elevated ((cs)RH = 1.71, 95% confidence interval: 1.37, 2.13 and (sd)RH = 2.01, 95% confidence interval: 1.62, 2.51). Methods for competing risks should be used by epidemiologists, with the choice of method guided by the scientific question.

Effect of early versus deferred antiretroviral therapy for HIV on survival

BACKGROUND

The optimal time for the initiation of antiretroviral therapy for asymptomatic patients with human immunodeficiency virus (HIV) infection is uncertain.

METHODS

We conducted two parallel analyses involving a total of 17,517 asymptomatic patients with HIV infection in the United States and Canada who received medical care during the period from 1996 through 2005. None of the patients had undergone previous antiretroviral therapy. In each group, we stratified the patients according to the CD4+ count (351 to 500 cells per cubic millimeter or >500 cells per cubic millimeter) at the initiation of antiretroviral therapy. In each group, we compared the relative risk of death for patients who initiated therapy when the CD4+ count was above each of the two thresholds of interest (early-therapy group) with that of patients who deferred therapy until the CD4+ count fell below these thresholds (deferred-therapy group).

RESULTS

In the first analysis, which involved 8362 patients, 2084 (25%) initiated therapy at a CD4+ count of 351 to 500 cells per cubic millimeter, and 6278 (75%) deferred therapy. After adjustment for calendar year, cohort of patients, and demographic and clinical characteristics, among patients in the deferred-therapy group there was an increase in the risk of death of 69%, as compared with that in the early-therapy group (relative risk in the deferred-therapy group, 1.69; 95% confidence interval [CI], 1.26 to 2.26; P<0.001). In the second analysis involving 9155 patients, 2220 (24%) initiated therapy at a CD4+ count of more than 500 cells per cubic millimeter and 6935 (76%) deferred therapy. Among patients in the deferred-therapy group, there was an increase in the risk of death of 94% (relative risk, 1.94; 95% CI, 1.37 to 2.79; P<0.001).

CONCLUSIONS

The early initiation of antiretroviral therapy before the CD4+ count fell below two prespecified thresholds significantly improved survival, as compared with deferred therapy.

Deployment of convalescent plasma for the prevention and treatment of COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), has spurred a global health crisis. To date, there are no proven options for prophylaxis for those who have been exposed to SARS-CoV-2, nor therapy for those who develop COVID-19. Immune (i.e., "convalescent") plasma refers to plasma that is collected from individuals following resolution of infection and development of antibodies. Passive antibody administration through transfusion of convalescent plasma may offer the only short-term strategy for conferring immediate immunity to susceptible individuals. There are numerous examples in which convalescent plasma has been used successfully as postexposure prophylaxis and/or treatment of infectious diseases, including other outbreaks of coronaviruses (e.g., SARS-1, Middle East respiratory syndrome [MERS]). Convalescent plasma has also been used in the COVID-19 pandemic; limited data from China suggest clinical benefit, including radiological resolution, reduction in viral loads, and improved survival. Globally, blood centers have robust infrastructure for undertaking collections and constructing inventories of convalescent plasma to meet the growing demand. Nonetheless, there are nuanced challenges, both regulatory and logistical, spanning donor eligibility, donor recruitment, collections, and transfusion itself. Data from rigorously controlled clinical trials of convalescent plasma are also few, underscoring the need to evaluate its use objectively for a range of indications (e.g., prevention vs. treatment) and patient populations (e.g., age, comorbid disease). We provide an overview of convalescent plasma, including evidence of benefit, regulatory considerations, logistical work flow, and proposed clinical trials, as scale-up is brought underway to mobilize this critical resource.

Risk of anal cancer in HIV-infected and HIV-uninfected individuals in North America

BACKGROUND

Anal cancer is one of the most common cancers affecting individuals infected with human immunodeficiency virus (HIV), although few have evaluated rates separately for men who have sex with men (MSM), other men, and women. There are also conflicting data regarding calendar trends.

METHODS

In a study involving 13 cohorts from North America with follow-up between 1996 and 2007, we compared anal cancer incidence rates among 34 189 HIV-infected (55% MSM, 19% other men, 26% women) and 114 260 HIV-uninfected individuals (90% men).

RESULTS

Among men, the unadjusted anal cancer incidence rates per 100 000 person-years were 131 for HIV-infected MSM, 46 for other HIV-infected men, and 2 for HIV-uninfected men, corresponding to demographically adjusted rate ratios (RRs) of 80.3 (95% confidence interval [CI], 42.7-151.1) for HIV-infected MSM and 26.7 (95% CI, 11.5-61.7) for other HIV-infected men compared with HIV-uninfected men. HIV-infected women had an anal cancer rate of 30/100 000 person-years, and no cases were observed for HIV-uninfected women. In a multivariable Poisson regression model, among HIV-infected individuals, the risk was higher for MSM compared with other men (RR, 3.3; 95% CI, 1.8-6.0), but no difference was observed comparing women with other men (RR, 1.0; 95% CI, 0.5-2.2). In comparison with the period 2000-2003, HIV-infected individuals had an adjusted RR of 0.5 (95% CI, .3-.9) in 1996-1999 and 0.9 (95% CI, .6-1.2) in 2004-2007.

CONCLUSIONS

Anal cancer rates were substantially higher for HIV-infected MSM, other men, and women compared with HIV-uninfected individuals, suggesting a need for universal prevention efforts. Rates increased after the early antiretroviral therapy era and then plateaued.

Selection Bias Due to Loss to Follow Up in Cohort Studies

Selection bias due to loss to follow up represents a threat to the internal validity of estimates derived from cohort studies. Over the past 15 years, stratification-based techniques as well as methods such as inverse probability-of-censoring weighted estimation have been more prominently discussed and offered as a means to correct for selection bias. However, unlike correcting for confounding bias using inverse weighting, uptake of inverse probability-of-censoring weighted estimation as well as competing methods has been limited in the applied epidemiologic literature. To motivate greater use of inverse probability-of-censoring weighted estimation and competing methods, we use causal diagrams to describe the sources of selection bias in cohort studies employing a time-to-event framework when the quantity of interest is an absolute measure (e.g., absolute risk, survival function) or relative effect measure (e.g., risk difference, risk ratio). We highlight that whether a given estimate obtained from standard methods is potentially subject to selection bias depends on the causal diagram and the measure. We first broadly describe inverse probability-of-censoring weighted estimation and then give a simple example to demonstrate in detail how inverse probability-of-censoring weighted estimation mitigates selection bias and describe challenges to estimation. We then modify complex, real-world data from the University of North Carolina Center for AIDS Research HIV clinical cohort study and estimate the absolute and relative change in the occurrence of death with and without inverse probability-of-censoring weighted correction using the modified University of North Carolina data. We provide SAS code to aid with implementation of inverse probability-of-censoring weighted techniques.

Hazardous alcohol use: a risk factor for non-adherence and lack of suppression in HIV infection

OBJECTIVE

We examined the independent effect of alcohol and combined effects of drug and alcohol use on antiretroviral (ART) utilization, adherence, and viral suppression in an urban cohort of HIV-infected individuals.

METHODS

In an observational clinical cohort, alcohol use, active drug use, and adherence were prospectively assessed at 6-month intervals. We classified hazardous alcohol use as >7 drinks/week or >3 drinks/occasion in women, and >14 drinks/week or >4 drinks/occasion in men and active drug use as any use in the previous 6 months. Our outcomes included ART utilization, 2-week adherence, and viral suppression. We used generalized estimating equations to analyze the association between independent variables and outcomes. Analyses were adjusted for age, sex, race, years on ART, and clinic enrollment time.

RESULTS

Between 1998 and 2003, 1711 individuals participated in 5028 interviews. 1433 of these individuals received ART accounting for 3761 interviews. The prevalence of any alcohol use at the first interview was 45%, with 10% classified as hazardous drinkers. One-third of the sample used illicit drugs. In multivariate analyses adjusting for age, sex, race, active drug use, years on ART, and clinic enrollment time, hazardous alcohol use was independently associated with decreased ART utilization (AOR, 0.65; 95% CI: 0.51 to 0.82), 2-week adherence (AOR, 0.46; 95% CI: 0.34 to 0.63), and viral suppression (AOR, 0.76; 95% CI: 0.57 to 0.99) compared to no alcohol use. Concurrent injection drug use (IDU) exacerbated this negative effect on ART use, adherence, and suppression.

CONCLUSIONS

Hazardous alcohol use alone and combined with IDU was associated with decreased ART uptake, adherence, and viral suppression. Interventions targeting alcohol use may improve HIV outcomes in individuals with hazardous alcohol use.

Cumulative Incidence of Cancer Among Persons With HIV in North America: A Cohort Study

BACKGROUND

Cancer is increasingly common among persons with HIV.

OBJECTIVE

To examine calendar trends in cumulative cancer incidence and hazard rate by HIV status.

DESIGN

Cohort study.

SETTING

North American AIDS Cohort Collaboration on Research and Design during 1996 to 2009.

PARTICIPANTS

86 620 persons with HIV and 196 987 uninfected adults.

MEASUREMENTS

Cancer type-specific cumulative incidence by age 75 years and calendar trends in cumulative incidence and hazard rates, each by HIV status.

RESULTS

Cumulative incidences of cancer by age 75 years for persons with and without HIV, respectively, were as follows: Kaposi sarcoma, 4.4% and 0.01%; non-Hodgkin lymphoma, 4.5% and 0.7%; lung cancer, 3.4% and 2.8%; anal cancer, 1.5% and 0.05%; colorectal cancer, 1.0% and 1.5%; liver cancer, 1.1% and 0.4%; Hodgkin lymphoma, 0.9% and 0.09%; melanoma, 0.5% and 0.6%; and oral cavity/pharyngeal cancer, 0.8% and 0.8%. Among persons with HIV, calendar trends in cumulative incidence and hazard rate decreased for Kaposi sarcoma and non-Hodgkin lymphoma. For anal, colorectal, and liver cancer, increasing cumulative incidence, but not hazard rate trends, were due to the decreasing mortality rate trend (-9% per year), allowing greater opportunity to be diagnosed. Despite decreasing hazard rate trends for lung cancer, Hodgkin lymphoma, and melanoma, cumulative incidence trends were not seen because of the compensating effect of the declining mortality rate.

LIMITATION

Secular trends in screening, smoking, and viral co-infections were not evaluated.

CONCLUSION

Cumulative cancer incidence by age 75 years, approximating lifetime risk in persons with HIV, may have clinical utility in this population. The high cumulative incidences by age 75 years for Kaposi sarcoma, non-Hodgkin lymphoma, and lung cancer support early and sustained antiretroviral therapy and smoking cessation.

Rising Obesity Prevalence and Weight Gain Among Adults Starting Antiretroviral Therapy in the United States and Canada

The proportion of overweight and obese adults in the United States and Canada has increased over the past decade, but temporal trends in body mass index (BMI) and weight gain on antiretroviral therapy (ART) among HIV-infected adults have not been well characterized. We conducted a cohort study comparing HIV-infected adults in the North America AIDS Cohort Collaboration on Research and Design (NA-ACCORD) to United States National Health and Nutrition Examination Survey (NHANES) controls matched by sex, race, and age over the period 1998 to 2010. Multivariable linear regression assessed the relationship between BMI and year of ART initiation, adjusting for sex, race, age, and baseline CD4(+) count. Temporal trends in weight on ART were assessed using a generalized least-squares model further adjusted for HIV-1 RNA and first ART regimen class. A total of 14,084 patients from 17 cohorts contributed data; 83% were male, 57% were nonwhite, and the median age was 40 years. Median BMI at ART initiation increased from 23.8 to 24.8 kg/m(2) between 1998 and 2010 in NA-ACCORD, but the percentage of those obese (BMI ≥30 kg/m(2)) at ART initiation increased from 9% to 18%. After 3 years of ART, 22% of individuals with a normal BMI (18.5-24.9 kg/m(2)) at baseline had become overweight (BMI 25.0-29.9 kg/m(2)), and 18% of those overweight at baseline had become obese. HIV-infected white women had a higher BMI after 3 years of ART as compared to age-matched white women in NHANES (p = 0.02), while no difference in BMI after 3 years of ART was observed for HIV-infected men or non-white women compared to controls. The high prevalence of obesity we observed among ART-exposed HIV-infected adults in North America may contribute to health complications in the future.

Exceeding the limits of liver histology markers

BACKGROUND/AIMS

Alternatives to liver biopsy for staging liver disease caused by hepatitis C virus (HCV) have not appeared accurate enough for widespread clinical use. We characterized the magnitude of the impact of error in the "gold standard" on the observed diagnostic accuracy of surrogate markers.

METHODS

We calculated the area under the receiver operating characteristic curve (AUROC) for a surrogate marker against the gold standard (biopsy) for a range of possible performances of each test (biopsy and marker) against truth and a gradient of clinically significant disease prevalence.

RESULTS

In the 'best' scenario where liver biopsy accuracy is highest (sensitivity and specificity of biopsy are 90%) and the prevalence of significant disease 40%, the calculated AUROC would be 0.90 for a perfect marker (99% actual accuracy) which is within the range of what has already been observed. With lower biopsy sensitivity and specificity, AUROC determinations > 0.90 could not be achieved even for a marker that perfectly measured disease.

CONCLUSIONS

We demonstrate that error in the liver biopsy result itself makes it impossible to distinguish a perfect surrogate from ones that are now judged by some as clinically unacceptable. An alternative gold standard is needed to assess the accuracy of tests used to stage HCV-related liver disease.

Early Outpatient Treatment for Covid-19 with Convalescent Plasma

BACKGROUND

Polyclonal convalescent plasma may be obtained from donors who have recovered from coronavirus disease 2019 (Covid-19). The efficacy of this plasma in preventing serious complications in outpatients with recent-onset Covid-19 is uncertain.

METHODS

In this multicenter, double-blind, randomized, controlled trial, we evaluated the efficacy and safety of Covid-19 convalescent plasma, as compared with control plasma, in symptomatic adults (≥18 years of age) who had tested positive for severe acute respiratory syndrome coronavirus 2, regardless of their risk factors for disease progression or vaccination status. Participants were enrolled within 8 days after symptom onset and received a transfusion within 1 day after randomization. The primary outcome was Covid-19-related hospitalization within 28 days after transfusion.

RESULTS

Participants were enrolled from June 3, 2020, through October 1, 2021. A total of 1225 participants underwent randomization, and 1181 received a transfusion. In the prespecified modified intention-to-treat analysis that included only participants who received a transfusion, the primary outcome occurred in 17 of 592 participants (2.9%) who received convalescent plasma and 37 of 589 participants (6.3%) who received control plasma (absolute risk reduction, 3.4 percentage points; 95% confidence interval, 1.0 to 5.8; P = 0.005), which corresponded to a relative risk reduction of 54%. Evidence of efficacy in vaccinated participants cannot be inferred from these data because 53 of the 54 participants with Covid-19 who were hospitalized were unvaccinated and 1 participant was partially vaccinated. A total of 16 grade 3 or 4 adverse events (7 in the convalescent-plasma group and 9 in the control-plasma group) occurred in participants who were not hospitalized.

CONCLUSIONS

In participants with Covid-19, most of whom were unvaccinated, the administration of convalescent plasma within 9 days after the onset of symptoms reduced the risk of disease progression leading to hospitalization. (Funded by the Department of Defense and others; CSSC-004 ClinicalTrials.gov number, NCT04373460.).

Importance of age of onset in pancreatic cancer kindreds

BACKGROUND

Young-onset cancer is a hallmark of many familial cancer syndromes, yet the implications of young-onset disease in predicting risk of pancreatic cancer among familial pancreatic cancer (FPC) kindred members remain unclear.

METHODS

To understand the relationship between age at onset of pancreatic cancer and risk of pancreatic cancer in kindred members, we compared the observed incidence of pancreatic cancer in 9040 individuals from 1718 kindreds enrolled in the National Familial Pancreas Tumor Registry with that observed in the general US population (Surveillance, Epidemiology, and End Results). Standardized incidence ratios (SIRs) were calculated for data stratified by familial vs sporadic cancer kindred membership, number of affected relatives, youngest age of onset among relatives, and smoking status. Competing risk survival analyses were performed to examine the risk of pancreatic cancer and risk of death from other causes according to youngest age of onset of pancreatic cancer in the family and the number of affected relatives.

RESULTS

Risk of pancreatic cancer was elevated in both FPC kindred members (SIR = 6.79, 95% confidence interval [CI] = 4.54 to 9.75, P < .001) and sporadic pancreatic cancer (SPC) kindred members (SIR = 2.41, 95% CI = 1.04 to 4.74, P = .04) compared with the general population. The presence of a young-onset patient (<50 years) in the family did not alter the risk for SPC kindred members (SIR = 2.74, 95% CI = 0.05 to 15.30, P = .59) compared with those without a young-onset case in the kindred (SIR = 2.36, 95% CI = 0.95 to 4.88, P = .06). However, risk was higher among members of FPC kindreds with a young-onset case in the kindred (SIR = 9.31, 95% CI = 3.42 to 20.28, P < .001) than those without a young-onset case in the kindred (SIR = 6.34, 95% CI = 4.02 to 9.51, P < .001). Competing risk survival analyses indicated that the lifetime risk of pancreatic cancer in FPC kindreds increased with decreasing age of onset in the kindred (hazard ratio = 1.55, 95% CI = 1.19 to 2.03 per year). However, youngest age of onset for pancreatic cancer in the kindred did not affect the risk among SPC kindred members.

CONCLUSIONS

Individuals with a family history of pancreatic cancer are at a statistically significantly increased risk of developing pancreatic cancer. Having a member of the family with a young-onset pancreatic cancer confers an added risk in FPC kindreds.

Chronic kidney disease incidence, and progression to end-stage renal disease, in HIV-infected individuals: a tale of two races

BACKGROUND

Little is known about the racial differences in the incidence and progression of HIV-related chronic kidney disease (CKD) that underlie African American-white disparities in HIV-related end-stage renal disease (ESRD).

METHODS

In a cohort in Baltimore, Maryland, we measured CKD incidence, glomerular filtration rate (GFR) slope, and progression to ESRD in 3332 African American and 927 white HIV-infected subjects.

RESULTS

A total of 284 subjects developed CKD, 100 (35%) of whom subsequently developed ESRD. African American subjects were at slightly increased risk for incident CKD, compared with white subjects (hazard ratio [HR], 1.9 [95% confidence interval {CI}, 1.2-2.8]). However, once CKD had commenced, the African American subjects developed ESRD markedly faster than did the white subjects (HR, 17.7 [95% CI, 2.5-127.0]), and, correspondingly, their GFR decline after diagnosis of CKD was 6-fold more rapid (P < .001). In the subset of African American subjects for whom kidney-biopsy data were available, progression to ESRD was significantly faster than that in white subjects with CKD, irrespective of the presence of HIV-associated nephropathy.

CONCLUSIONS

The results of this study suggest that African American-white disparities in HIV-related ESRD are explained predominantly by a more aggressive natural disease history in African Americans and less by racial differences in CKD incidence.

C-Reactive Protein Is a Marker for Human Immunodeficiency Virus Disease Progression

BACKGROUND

Limited data on acute-phase C-reactive protein (CRP) levels in human immunodeficiency virus (HIV) infection exist.

METHODS

We obtained a single measurement of CRP from 513 HIV-infected men in the Multicenter AIDS Cohort Study to examine the association between CRP and immune suppression and progression to AIDS. We estimated changes in CRP during the course of HIV infection in 81 of these individuals using specimens collected from October 1, 1984, to December 31, 1996.

RESULTS

The cross-sectional associations between log(10) CRP were correlated inversely with CD4 lymphocyte counts (r=-0.17; P<.001) and directly with log10 HIV RNA levels (r=0.20; P<.001). Levels of CRP of more than 2.3 mg/L were associated with a decreased time to the development of AIDS (relative time to AIDS, 0.36; P<.001) compared with individuals with CRP levels of 1.2 mg/L or less, which remained significant after adjustment for CD4 lymphocyte counts and HIV RNA and hemoglobin concentrations. Levels of CRP significantly increased over time with mean slopes of 8.5% (95% confidence interval, 4.9%-12.2%) and 4.5% (95% confidence interval CI, 2.1%-6.9%) per year for individuals with and without progression to AIDS, respectively. Individuals had a geometric mean CRP level of 2.5 mg/L in the 6-month interval before progression to AIDS, which was an increase from a nadir of 1.0 mg/L at 6.5 years before progression to AIDS.

CONCLUSIONS

Levels of CRP were associated with HIV disease progression independent of CD4 lymphocyte counts and HIV RNA levels. In addition, regardless of progression to AIDS, HIV-infected individuals had a significant increase in CRP over time. This may have implications for cardiovascular disease among HIV-infected individuals.

Viremia copy-years predicts mortality among treatment-naive HIV-infected patients initiating antiretroviral therapy

BACKGROUND

Cross-sectional plasma human immunodeficiency virus (HIV) viral load (VL) measures have proven invaluable for clinical and research purposes. However, cross-sectional VL measures fail to capture cumulative plasma HIV burden longitudinally. We evaluated the cumulative effect of exposure to HIV replication on mortality following initiation of combination antiretroviral therapy (ART).

METHODS

We included treatment-naive HIV-infected patients starting ART from 2000 to 2008 at 8 Center for AIDS Research Network of Integrated Clinical Systems sites. Viremia copy-years, a time-varying measure of cumulative plasma HIV exposure, were determined for each patient using the area under the VL curve. Multivariable Cox models were used to evaluate the independent association of viremia copy-years for all-cause mortality.

RESULTS

Among 2027 patients contributing 6579 person-years of follow-up, the median viremia copy-years was 5.3 log₁₀ copy × y/mL (interquartile range: 4.9-6.3 log₁₀ copy × y/mL), and 85 patients (4.2%) died. When evaluated separately, viremia copy-years (hazard ratio [HR] = 1.81 per log₁₀ copy × y/mL; 95% confidence interval [CI], 1.51-2.18 per log(10) copy × y/mL), 24-week VL (1.74 per log₁₀ copies/mL; 95% CI, 1.48-2.04 per log₁₀ copies/mL), and most recent VL (HR = 1.89 per log₁₀ copies/mL; 95% CI: 1.63-2.20 per log₁₀ copies/mL) were associated with increased mortality. When simultaneously evaluating VL measures and controlling for other covariates, viremia copy-years increased mortality risk (HR = 1.44 per log₁₀ copy × y/mL; 95% CI, 1.07-1.94 per log₁₀ copy × y/mL), whereas no cross-sectional VL measure was independently associated with mortality.

CONCLUSIONS

Viremia copy-years predicted all-cause mortality independent of traditional, cross-sectional VL measures and time-updated CD4+ T-lymphocyte count in ART-treated patients, suggesting cumulative HIV replication causes harm independent of its effect on the degree of immunodeficiency.

Incidence of AIDS-Defining Opportunistic Infections in a Multicohort Analysis of HIV-infected Persons in the United States and Canada, 2000-2010

BACKGROUND

There are few recent data on the rates of AIDS-defining opportunistic infections (OIs) among human immunodeficiency virus (HIV)-infected patients in care in the United States and Canada.

METHODS

We studied HIV-infected participants in 16 cohorts in the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) during 2000-2010. After excluding 16 737 (21%) with any AIDS-defining clinical events documented before NA-ACCORD enrollment, we analyzed incident OIs among the remaining 63 541 persons, most of whom received antiretroviral therapy during the observation. We calculated incidence rates per 100 person-years of observation (hereafter, "person-years") with 95% confidence intervals (CIs) for the first occurrence of any OI and select individual OIs during 2000-2003, 2004-2007, and 2008-2010.

RESULTS

A total of 63 541 persons contributed 261 573 person-years, of whom 5836 (9%) developed at least 1 OI. The incidence rate of any first OI decreased over the 3 observation periods, with 3.0 cases, 2.4 cases, and 1.5 cases per 100 person-years of observation during 2000-2003, 2004-2007, and 2008-2010, respectively (Ptrend<.001); the rates of most individual OIs decreased as well. During 2008-2010, the leading OIs included Pneumocystis jiroveci pneumonia, esophageal candidiasis, and disseminated Mycobacterium avium complex or Mycobacterium kansasii infection.

CONCLUSIONS

For HIV-infected persons in care during 2000-2010, rates of first OI were relatively low and generally declined over this time.

Association of race and gender with HIV-1 RNA levels and immunologic progression

CONTEXT

HIV-1 RNA and lymphocyte subset levels are the principal indications for antiretroviral treatment. Past reports have differed with regard to the effect of gender and race on these measures and in measures of disease progression.

OBJECTIVE

To assess racial and gender differences in HIV-1 RNA levels and CD4+ lymphocyte decline.

DESIGN

A longitudinal study based in the two largest HIV natural history cohort studies conducted in 7 metropolitan areas of the United States.

RESULTS

In all, 1256 adult women and 1603 adult men for whom multiple data points were available prior to initiation of antiretroviral therapy were included. Women were more likely to be nonwhite, to have a history of injection drug use, and to have HIV-associated symptoms. After adjustment for differences in measurement method, baseline CD4+ cell count, age, and clinical symptoms, HIV-1 RNA levels were 32% to 50% lower in women than in men at CD4+ counts >200 cells/mm3 (p <.001) but not at CD4+ cell counts <200 cells/mm3. HIV-1 RNA levels were also 41% lower in nonwhites than in whites (p <.001) and 21% lower in persons reporting a prior history of injection drug use (p <.001). Women had more rapid declines in CD4+ cell counts over time than men (difference in slope of 46 cells/year) and nonwhite individuals had slower decline in CD4 cell counts than whites (difference of 39 cells/year).

CONCLUSIONS

Both race and gender influence the values of HIV-1 RNA and the rate of HIV-1 disease progression as indicated by decline in CD4 cell counts over time. These effects could provide clues regarding the factors that influence HIV-disease progression and may indicate that guidelines for therapy should be adjusted for demographic characteristics.

Risk of Non-AIDS-Related Mortality May Exceed Risk of AIDS-Related Mortality Among Individuals Enrolling Into Care With CD4+ Counts Greater Than 200 Cells/mm3

OBJECTIVE

To quantify cause-specific mortality risk attributable to non-AIDS-related and AIDS-related causes before and after the advent of highly active antiretroviral therapy (HAART).

METHODS

Competing-risk methods were used to determine the cumulative AIDS-related and non-AIDS-related risk of mortality between 1990 and the end of 2003 in the Johns Hopkins HIV Clinical Cohort, a prospective cohort study.

RESULTS

Beginning in 1997 with the introduction of HAART, all-cause mortality declined and has remained stable at approximately 39 deaths per 1000 person-years. AIDS-related mortality continued to decline in this period (P = 0.008), whereas non-AIDS-related mortality increased (P < 0.001). Using competing-risk methods, the risk of dying attributable to AIDS-related causes remains significantly higher than the risk of dying attributable to non-AIDS-related causes for patients with a CD4 count <or=200 cells/mm in the HAART era. For those with a CD4 count >200 cells/mm, however, non-AIDS-related mortality was greater than AIDS-related mortality, particularly among injection drug users. Other transmission categories had similar AIDS-related and non-AIDS-related cumulative mortalities.

CONCLUSIONS

HAART has reduced mortality rates among HIV-infected individuals, but further efforts to reduce mortality in this population require increased attention to conditions that have not traditionally been considered to be HIV related.

Clinic-based treatment of opioid-dependent HIV-infected patients versus referral to an opioid treatment program: A randomized trial

BACKGROUND

Opioid dependence is common in HIV clinics. Buprenorphine-naloxone (BUP) is an effective treatment of opioid dependence that may be used in routine medical settings.

OBJECTIVE

To compare clinic-based treatment with BUP (clinic-based BUP) with case management and referral to an opioid treatment program (referred treatment).

DESIGN

Single-center, 12-month randomized trial. Participants and investigators were aware of treatment assignments. (ClinicalTrials.gov registration number: NCT00130819)

SETTING

HIV clinic in Baltimore, Maryland.

PATIENTS

93 HIV-infected, opioid-dependent participants who were not receiving opioid agonist therapy and were not dependent on alcohol or benzodiazepines.

INTERVENTION

Clinic-based BUP included BUP induction and dose titration, urine drug testing, and individual counseling. Referred treatment included case management and referral to an opioid-treatment program.

MEASUREMENTS

Initiation and long-term receipt of opioid agonist therapy, urine drug test results, visit attendance with primary HIV care providers, use of antiretroviral therapy, and changes in HIV RNA levels and CD4 cell counts.

RESULTS

The average estimated participation in opioid agonist therapy was 74% (95% CI, 61% to 84%) for clinic-based BUP and 41% (CI, 29% to 53%) for referred treatment (P < 0.001). Positive test results for opioids and cocaine were significantly less frequent in clinic-based BUP than in referred treatment, and study participants receiving clinic-based BUP attended significantly more HIV primary care visits than those receiving referred treatment. Use of antiretroviral therapy and changes in HIV RNA levels and CD4 cell counts did not differ between the 2 groups.

LIMITATION

This was a small single-center study, follow-up was only moderate, and the study groups were unbalanced in terms of recent drug injections at baseline.

CONCLUSION

Management of HIV-infected, opioid-dependent patients with a clinic-based BUP strategy facilitates access to opioid agonist therapy and improves outcomes of substance abuse treatment.

PRIMARY FUNDING SOURCE

Health Resources and Services Administration Special Projects of National Significance program.

HIV Viral Suppression Trends Over Time Among HIV-Infected Patients Receiving Care in the United States, 1997 to 2015: A Cohort Study

BACKGROUND

Because HIV viral suppression is essential for optimal outcomes and prevention efforts, understanding trends and predictors is imperative to inform public health policy.

OBJECTIVE

To evaluate viral suppression trends in people living with HIV (PLWH), including the relationship of associated factors, such as demographic characteristics and integrase strand transfer inhibitor (ISTI) use.

DESIGN

Longitudinal observational cohort study.

SETTING

8 HIV clinics across the United States.

PARTICIPANTS

PLWH receiving clinical care.

MEASUREMENTS

To understand trends in viral suppression (≤400 copies/mL), annual viral suppression rates from 1997 to 2015 were determined. Analyses were repeated with tests limited to 1 random test per person per year and using inverse probability of censoring weights to address loss to follow-up. Joint longitudinal and survival models and linear mixed models of PLWH receiving antiretroviral therapy (ART) were used to examine associations between viral suppression or continuous viral load (VL) levels and demographic factors, substance use, adherence, and ISTI use.

RESULTS

Viral suppression increased from 32% in 1997 to 86% in 2015 on the basis of all tests among 31 930 PLWH. In adjusted analyses, being older (odds ratio [OR], 0.76 per decade [95% CI, 0.74 to 0.78]) and using an ISTI-based regimen (OR, 0.54 [CI, 0.51 to 0.57]) were associated with lower odds of having a detectable VL, and black race was associated with higher odds (OR, 1.68 [CI, 1.57 to 1.80]) (P < 0.001 for each). Similar patterns were seen with continuous VL levels; when analyses were limited to 2010 to 2015; and with adjustment for adherence, substance use, or depression.

LIMITATION

Results are limited to PLWH receiving clinical care.

CONCLUSION

HIV viral suppression rates have improved dramatically across the United States, which is likely partially attributable to improved ART, including ISTI-based regimens. However, disparities among younger and black PLWH merit attention.

PRIMARY FUNDING SOURCE

National Institutes of Health.

Trends and disparities in antiretroviral therapy initiation and virologic suppression among newly treatment-eligible HIV-infected individuals in North America, 2001-2009

BACKGROUND

Since the mid-1990s, effective antiretroviral therapy (ART) regimens have improved in potency, tolerability, ease of use, and class diversity. We sought to examine trends in treatment initiation and resulting human immunodeficiency virus (HIV) virologic suppression in North America between 2001 and 2009, and demographic and geographic disparities in these outcomes.

METHODS

We analyzed data on HIV-infected individuals newly clinically eligible for ART (ie, first reported CD4+ count<350 cells/µL or AIDS-defining illness, based on treatment guidelines during the study period) from 17 North American AIDS Cohort Collaboration on Research and Design cohorts. Outcomes included timely ART initiation (within 6 months of eligibility) and virologic suppression (≤500 copies/mL, within 1 year). We examined time trends and considered differences by geographic location, age, sex, transmission risk, race/ethnicity, CD4+ count, and viral load, and documented psychosocial barriers to ART initiation, including non-injection drug abuse, alcohol abuse, and mental illness.

RESULTS

Among 10,692 HIV-infected individuals, the cumulative incidence of 6-month ART initiation increased from 51% in 2001 to 72% in 2009 (Ptrend<.001). The cumulative incidence of 1-year virologic suppression increased from 55% to 81%, and among ART initiators, from 84% to 93% (both Ptrend<.001). A greater number of psychosocial barriers were associated with decreased ART initiation, but not virologic suppression once ART was initiated. We found significant heterogeneity by state or province of residence (P<.001).

CONCLUSIONS

In the last decade, timely ART initiation and virologic suppression have greatly improved in North America concurrent with the development of better-tolerated and more potent regimens, but significant barriers to treatment uptake remain, both at the individual level and systemwide.

Dissociation of food and opiate preference by a genetic mutation in zebrafish

Both natural rewards and addictive substances have the ability to reinforce behaviors. It has been unclear whether identical neural pathways mediate the actions of both. In addition, little is known about these behaviors and the underlying neural mechanisms in a genetically tractable vertebrate, the zebrafish Danio rerio. Using a conditioned place preference paradigm, we demonstrate that wildtype zebrafish exhibit a robust preference for food as well as the opiate drug morphine that can be blocked by the opioid receptor antagonist naloxone. Moreover, we show that the too few mutant, which disrupts a conserved zinc finger-containing gene and exhibits a reduction of selective groups of dopaminergic and serotonergic neurons in the basal diencephalon, displays normal food preference but shows no preference for morphine. Pretreatment with dopamine receptor antagonists abolishes morphine preference in the wildtype. These studies demonstrate that zebrafish display measurable preference behavior for reward and show that the preference for natural reward and addictive drug is dissociable by a single-gene mutation that alters subregions of brain monoamine neurotransmitter systems. Future genetic analysis in zebrafish shall uncover further molecular and cellular mechanisms underlying the formation and function of neural circuitry that regulate opiate and food preference behavior.

Copy-years viremia as a measure of cumulative human immunodeficiency virus viral burden

Plasma human immunodeficiency virus type 1 (HIV-1) viral load is a valuable tool for HIV research and clinical care but is often used in a noncumulative manner. The authors developed copy-years viremia as a measure of cumulative plasma HIV-1 viral load exposure among 297 HIV seroconverters from the Multicenter AIDS Cohort Study (1984-1996). Men were followed from seroconversion to incident acquired immunodeficiency syndrome (AIDS), death, or the beginning of the combination antiretroviral therapy era (January 1, 1996); the median duration of follow-up was 4.6 years (interquartile range (IQR), 2.7-6.5). The median viral load and level of copy-years viremia over 2,281 semiannual follow-up assessments were 29,628 copies/mL (IQR, 8,547-80,210) and 63,659 copies x years/mL (IQR, 15,935-180,341). A total of 127 men developed AIDS or died, and 170 survived AIDS-free and were censored on January 1, 1996, or lost to follow-up. Rank correlations between copy-years viremia and other measures of viral load were 0.56-0.87. Each log(10) increase in copy-years viremia was associated with a 1.70-fold increased hazard (95% confidence interval: 0.94, 3.07) of AIDS or death, independently of infection duration, age, race, CD4 cell count, set-point, peak viral load, or most recent viral load. Copy-years viremia, a novel measure of cumulative viral burden, may provide prognostic information beyond traditional single measures of viremia.

All-Cause and Cardiovascular Disease Mortality Among Breast Cancer Survivors in CLUE II, a Long-Standing Community-Based Cohort

BACKGROUND

There is growing evidence that breast cancer survivors have higher cardiovascular disease (CVD) mortality relative to the general population. Information on temporal patterns for all-cause and CVD mortality among breast cancer survivors relative to cancer-free women is limited.

METHODS

All-cause and CVD-related mortality were compared in 628 women with breast cancer and 3140 age-matched cancer-free women within CLUE II, a prospective cohort. We calculated adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) using Cox proportional hazards regression for all-cause mortality, and Fine and Gray models for CVD-related mortality to account for competing risks.

RESULTS

Over 25 years of follow-up, 916 deaths occurred (249 CVD related). Breast cancer survivors had an overall higher risk of dying compared with cancer-free women (HR = 1.79, 95% CI = 1.53 to 2.09) irrespective of time since diagnosis, tumor stage, estrogen receptor status, and older age at diagnosis (≥70 years). Risk of death was greatest among older survivors at more than 15 years after diagnosis (HR = 2.69, 95% CI = 1.59 to 4.55). CVD (69.1% ischemic heart disease) was the leading cause of death among cancer-free women and the second among survivors. Survivors had an increase in CVD-related deaths compared with cancer-free women beginning at 8 years after diagnosis (HR = 1.65, 95% CI = 1.00 to 2.73), with the highest risk among older survivors (HR = 2.24, 95% CI = 1.29 to 3.88) and after estrogen receptor-positive disease (HR = 1.85, 95% CI = 1.06 to 3.20).

CONCLUSIONS

Breast cancer survivors continue to have an elevated mortality compared with the general population for many years after diagnosis. Preventing cardiac deaths, particularly among older breast cancer patients, could lead to reductions in mortality.

HIV infection, immune suppression, and uncontrolled viremia are associated with increased multimorbidity among aging injection drug users

BACKGROUND

Despite an increasing burden of age-associated non-AIDS outcomes, few studies have investigated the prevalence or correlates of multimorbidity among aging human immunodeficiency virus (HIV)-infected and epidemiologically comparable at-risk populations.

METHODS

Among 1262 AIDS Linked to the IntraVenous Experience (ALIVE) study participants followed in a community-based observational cohort, we defined the prevalence of 7 non-AIDS-defining chronic conditions (diabetes, obstructive lung disease, liver disease, anemia, obesity, kidney dysfunction, and hypertension) using clinical and laboratory criteria. Ordinal logistic regression was used to model the odds of increased multimorbidity associated with demographic, behavioral, and clinical factors. Self-reported prevalence was compared with clinically defined prevalence.

RESULTS

Participants were a median of 48.9 years of age; 65.1% were male, 87.5% were African-American, and 28.7% were HIV infected. In multivariable analysis, HIV infection (odds ratio [OR], 1.50; 95% confidence interval [CI], 1.13-1.99) was positively associated with increased multimorbidity. Among HIV-infected participants, multimorbidity was increased with lower nadir CD4 T-cell count (OR, 1.14 per 100-cell decrease; 95% CI, 1.00-1.29) and higher current HIV RNA (OR, 1.32 per log(10) increase; 95% CI, 1.08-1.60). Older age, being female, not using cigarettes or drugs, and having depressive symptoms were also associated with increased multimorbidity. A substantial proportion of multimorbid conditions in HIV-infected and HIV-uninfected participants were unrecognized and untreated.

CONCLUSIONS

HIV-infected participants experienced increased numbers of multimorbid conditions; risk increased with advanced immunosuppression and higher viremia. These results underscore the heavy burden of multimorbidity associated with HIV and highlight the need for incorporating routine assessment and integrated management of chronic diseases as part of comprehensive healthcare for aging, HIV-infected persons.

CA, Catellier D, Cordero JF, Croen L, Dabelea D, Deoni S, D’Sa V, Duarte CS, Dunlop AL, Elliott AJ, Farzan SF, Ferrara A, Ganiban JM, Gern JE, Giardino AP, Towe-Goodman NR, Gold DR, Habre R, Hamra GB, Hartert T, Herbstman JB, Hertz-Picciotto I, Hipwell AE, Karagas MR, Karr CJ, Keenan K, Kerver JM, Koinis-Mitchell D, Lau B, Lester BM, Leve LD, Leventhal B, LeWinn KZ, Lewis J, Litonjua AA, Lyall K, Madan JC, McEvoy CT, McGrath M, Meeker JD, Miller RL, Morello-Frosch R, Neiderhiser JM, O’Connor TG, Oken E, O’Shea M, Paneth N, Porucznik CA, Sathyanarayana S, Schantz SL, Spindel ER, Stanford JB, Stroustrup A, Teitelbaum SL, Trasande L, Volk H, Wadhwa PD, Weiss ST, Woodruff TJ, Wright RJ, Zhao Q, Jacobson LP, Influences on Child Health Outcomes ,OBOPCFE. The Environmental Influences on Child Health Outcomes (ECHO)-Wide Cohort

The Environmental Influences on Child Health Outcomes (ECHO)-Wide Cohort Study (EWC), a collaborative research design comprising 69 cohorts in 31 consortia, was funded by the National Institutes of Health (NIH) in 2016 to improve children's health in the United States. The EWC harmonizes extant data and collects new data using a standardized protocol, the ECHO-Wide Cohort Data Collection Protocol (EWCP). EWCP visits occur at least once per life stage, but the frequency and timing of the visits vary across cohorts. As of March 4, 2022, the EWC cohorts contributed data from 60,553 children and consented 29,622 children for new EWCP data and biospecimen collection. The median (interquartile range) age of EWCP-enrolled children was 7.5 years (3.7-11.1). Surveys, interviews, standardized examinations, laboratory analyses, and medical record abstraction are used to obtain information in 5 main outcome areas: pre-, peri-, and postnatal outcomes; neurodevelopment; obesity; airways; and positive health. Exposures include factors at the level of place (e.g., air pollution, neighborhood socioeconomic status), family (e.g., parental mental health), and individuals (e.g., diet, genomics).