Gross, Robert

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  • Publication
    Overestimates of Survival After HAART: Implications for Global Scale-Up Efforts
    (2008-03-05) Bisson, Gregory P; Gross, Robert; Bellamy, Scarlett; Gaolathe, Tendani; Friedman, Harvey M; Rollins, Caitlin; Frank, Ian; Mogorosi, Mpho; Avalos, Ava; Dickinson, Diana; Ndwapi, Ndwapi
    Background Monitoring the effectiveness of global antiretroviral therapy scale-up efforts in resource-limited settings is a global health priority, but is complicated by high rates of losses to follow-up after treatment initiation. Determining definitive outcomes of these lost patients, and the effects of losses to follow-up on estimates of survival and risk factors for death after HAART, are key to monitoring the effectiveness of global HAART scale-up efforts. Methodology/Principal Findings A cohort study comparing clinical outcomes and risk factors for death after HAART initiation as reported before and after tracing of patients lost to follow-up was conducted in Botswana's National Antiretroviral Therapy Program. 410 HIV-infected adults consecutively presenting for HAART were evaluated. The main outcome measures were death or loss to follow-up within the first year after HAART initiation. Of 68 patients initially categorized as lost, over half (58.8%) were confirmed dead after tracing. Patient tracing resulted in reporting of significantly lower survival rates when death was used as the outcome and losses to follow-up were censored [1-year Kaplan Meier survival estimate 0.92 (95% confidence interval, 0.88–0.94 before tracing and 0.83 (95% confidence interval, 0.79–0.86) after tracing, log rank P<0.001]. In addition, a significantly increased risk of death after HAART among men [adjusted hazard ratio 1.74 (95% confidence interval, 1.05–2.87)] would have been missed had patients not been traced [adjusted hazard ratio 1.41 (95% confidence interval, 0.65–3.05)]. Conclusions/Significance Due to high rates of death among patients lost to follow-up after HAART, survival rates may be inaccurate and important risk factors for death may be missed if patients are not actively traced. Patient tracing and uniform reporting of outcomes after HAART are needed to enable accurate monitoring of global HAART scale-up efforts.
  • Publication
    Pain and Physical and Psychological Symptoms in Ambulatory HIV Patients in the Current Treatment Era
    (2012-03-01) Praestgaard, Amy; Merlin, Jessica S; Cen, Liyi; Casarett, David; Turner, Michelle; Kostman, Jay R; Obando, Aura; Gross, Robert; Alpert, Craig; Frank, Ian; Woolston, Sophie
    Context HIV infection has become a manageable chronic disease. There are few studies of pain and symptoms in the current treatment era. Objectives The primary objective was to determine the prevalence of and risk factors for pain and physical and psychological symptoms in a population of ambulatory HIV patients. Methods We performed a cross-sectional study using the Brief Pain Inventory and the Memorial Symptom Assessment Scale. Results We evaluated 156 individuals with a median age of 47.5 years (range 21–71), median time since HIV diagnosis of 11 years (range 3(interquartile range [IQR] 308–683). The majority (125, 80.6%) had an undetectable viral load. Seventy-six (48.7%) reported pain, of whom 39 (51.3%) had moderate to severe pain, and 43 (57.3%) had pain that caused moderate to severe interference with their lives. The median number of symptoms was eight (IQR 5–14.5) of 32 queried. In multivariable analyses, patients with psychiatric illness were 39.8% more likely to have pain (P Conclusion Pain and other physical and psychological symptoms were common among ambulatory HIV patients. Pain and symptoms were strongly associated with psychiatric illness and IV drug use. Future investigation should evaluate interventions that include psychiatric and substance abuse components for HIV patients with pain.
  • Publication
    Association Between Efavirenz-Based Compared With Nevirapine-Based Antiretroviral Regimens and Virological Failure in HIV-Infected Children
    (2013-05-01) Lowenthal, Elizabeth D; Ellenberg, Jonas H; Steenhoff, Andrew P; Rutstein, Richard M; Machine, Edwin; Sagdeo, Aditi; Gross, Robert; Boiditswe, Sefelani; Anabwani, Gabriel
    Importance Worldwide, the nonnucleoside reverse transcriptase inhibitors (NNRTIs) efavirenz and nevirapine are commonly used in first-line antiretroviral regimens in both adults and children with human immunodeficiency virus (HIV) infection. Data on the comparative effectiveness of these medications in children are limited. Objective To investigate whether virological failure is more likely among children who initiated 1 or the other NNRTI-based HIV treatment. Design, Setting, and Participants Retrospective cohort study of children (aged 3–16 years) who initiated efavirenz-based (n=421) or nevirapine-based (n=383) treatment between April 2002 and January 2011 at a large pediatric HIV care setting in Botswana. Main Outcomes and Measures The primary outcome was time from initiation of therapy to virological failure. Virological failure was defined as lack of plasma HIV RNA suppression to less than 400 copies/mL by 6 months or confirmed HIV RNA of 400 copies/mL or greater after suppression. Cox proportional hazards regression analysis compared time to virological failure by regimen. Multivariable Cox regression controlled for age, sex, baseline immunologic category, baseline clinical category, baseline viral load, nutritional status, NRTIs used, receipt of single-dose nevirapine, and treatment for tuberculosis. Results With a median follow-up time of 69 months (range, 6–112 months; interquartile range, 23–87 months), 57 children (13.5%; 95% CI, 10.4%–17.2%) initiating treatment with efavirenz and 101 children (26.4%; 95% CI, 22.0%–31.1%) initiating treatment with nevirapine had virological failure. There were 11 children (2.6%; 95% CI, 1.3%–4.6%) receiving efavirenz and 20 children (5.2%; 95% CI, 3.2%–7.9%) receiving nevirapine who never achieved virological suppression. The Cox proportional hazard ratio for the combined virological failure end point was 2.0 (95% CI, 1.4–2.7; log rank P Conclusions and Relevance Among children aged 3 to 16 years infected with HIV and treated at a clinic in Botswana, the use of efavirenz compared with nevirapine as initial antiretroviral treatment was associated with less virological failure. These findings may warrant additional research evaluating the use of efavirenz and nevirapine for pediatric patients.
  • Publication
    Validation of the Pediatric Symptom Checklist in HIV-Infected Batswana
    (2011-08-22) Lowenthal, Elizabeth D; Lawler, Kathy; Harari, Nurit; Moamogwe, Lesedi; Masunge, Japhter; Masedi, Motshodi; Matome, Bolefela; Seloilwe, Esther; Gross, Robert; Jellinek, Michael; Murphy, Michael
    Objective—To determine the validity of the Pediatric Symptom Checklist (PSC), a brief measure of psychosocial health, for screening HIV+ Batswana children. Method—Setswana versions of the parent and child PSC were administered to 509 HIV+ Batswana children (age 8–16) and their parents/guardians. Test properties were evaluated and cutoff scores were derived using receiver operating characteristic curve analysis. Scores on the parent-completed PSC and the child-completed PSC-Y were compared to parental and clinic staff reports of concern about the child’s psychosocial health and to scores on the Children’s Depression Inventory and the Revised Children’s Manifest Anxiety Scale. Results—The Setswana PSC has high internal consistency (Cronbach’s alpha 0.87 for the parent-completed version). Comparing PSC scores to parental reports of concern and childreported depression symptoms, a cut-off score of 20 on the PSC and PSC-Y maximised the sensitivity and specificity. Conclusions—The PSC performed well in Setswana-speaking children and is a promising screening tool for paediatric psychosocial problems in busy clinical settings. Screening with the PSC may allow for early detection and treatment of psychosocial problems. This is likely to be of particular value for HIV+ children for whom HIV treatment non-adherence may result from untreated psychosocial dysfunction.
  • Publication
    Pharmacy Refill Adherence Compared With CD4 Count Changes for Monitoring HIV-Infected Adults on Antiretroviral Therapy
    (2008-05-20) Bisson, Gregory P; Gross, Robert; Bellamy, Scarlett; Chittams, Jess; Frank, Ian; Hislop, Michael; Maartens, Gary; Nachega, Jean B
    Background World Health Organization (WHO) guidelines for monitoring HIV-infected individuals taking combination antiretroviral therapy (cART) in resource-limited settings recommend using CD4+ T cell (CD4) count changes to monitor treatment effectiveness. In practice, however, falling CD4 counts are a consequence, rather than a cause, of virologic failure. Adherence lapses precede virologic failure and, unlike CD4 counts, data on adherence are immediately available to all clinics dispensing cART. However, the accuracy of adherence assessments for predicting future or detecting current virologic failure has not been determined. The goal of this study therefore was to determine the accuracy of adherence assessments for predicting and detecting virologic failure and to compare the accuracy of adherence-based monitoring approaches with approaches monitoring CD4 count changes. Methodology and Findings We conducted an observational cohort study among 1,982 of 4,984 (40%) HIV-infected adults initiating non-nucleoside reverse transcriptase inhibitor-based cART in the Aid for AIDS Disease Management Program, which serves nine countries in southern Africa. Pharmacy refill adherence was calculated as the number of months of cART claims submitted divided by the number of complete months between cART initiation and the last refill prior to the endpoint of interest, expressed as a percentage. The main outcome measure was virologic failure defined as a viral load > 1,000 copies/ml (1) at an initial assessment either 6 or 12 mo after cART initiation and (2) after a previous undetectable (i.e., < 400 copies/ml) viral load (breakthrough viremia). Adherence levels outperformed CD4 count changes when used to detect current virologic failure in the first year after cART initiation (area under the receiver operating characteristic [ROC] curves [AUC] were 0.79 and 0.68 [difference = 0.11; 95% CI 0.06 to 0.16; χ2 = 20.1] respectively at 6 mo, and 0.85 and 0.75 [difference = 0.10; 95% CI 0.05 to 0.14; χ2 = 20.2] respectively at 12 mo; p < 0.001 for both comparisons). When used to detect current breakthrough viremia, adherence and CD4 counts were equally accurate (AUCs of 0.68 versus 0.67, respectively [difference = 0.01; 95% CI −0.06 to 0.07]; χ2 = 0.1, p > 0.5). In addition, adherence levels assessed 3 mo prior to viral load assessments were as accurate for virologic failure occurring approximately 3 mo later as were CD4 count changes calculated from cART initiation to the actual time of the viral load assessments, indicating the potential utility of adherence assessments for predicting future, rather than simply detecting current, virologic failure. Moreover, combinations of CD4 count and adherence data appeared useful in identifying patients at very low risk of virologic failure. Conclusions Pharmacy refill adherence assessments were as accurate as CD4 counts for detecting current virologic failure in this cohort of patients on cART and have the potential to predict virologic failure before it occurs. Approaches to cART scale-up in resource-limited settings should include an adherence-based monitoring approach.
  • Publication
    Randomized Trial of Time-Limited Interruptions of Protease Inhibitor-Based Antiretroviral Therapy (ART) vs. Continuous Therapy for HIV-1 Infection
    (2011-06-28) Firnhaber, Cynthia; Azzoni, Livio; Foulkes, Andrea S; Gross, Robert; Yin, Xiangan; Van Amsterdam, Desiree; Schulze, Doreen; Glencross, Deborah K; Stevens, Wendy; Hunt, Gillian; Morris, Lynn; Fox, Lawerence; Sanne, Ian; Montaner, Luis J
    Background The clinical outcomes of short interruptions of PI-based ART regimens remains undefined. Methods A 2-arm non-inferiority trial was conducted on 53 HIV-1 infected South African participants with viral load/ml and CD4 T cell count >450 cells/µl on stavudine (or zidovudine), lamivudine and lopinavir/ritonavir. Subjects were randomized to a) sequential 2, 4 and 8-week ART interruptions or b) continuous ART (cART). Primary analysis was based on the proportion of CD4 count >350 cells(c)/ml over 72 weeks. Adherence, HIV-1 drug resistance, and CD4 count rise over time were analyzed as secondary endpoints. Results The proportions of CD4 counts >350 cells/µl were 82.12% for the intermittent arm and 93.73 for the cART arm; the difference of 11.95% was above the defined 10% threshold for non-inferiority (upper limit of 97.5% CI, 24.1%; 2-sided CI: −0.16, 23.1). No clinically significant differences in opportunistic infections, adverse events, adherence or viral resistance were noted; after randomization, long-term CD4 rise was observed only in the cART arm. Conclusion We are unable to conclude that short PI-based ART interruptions are non-inferior to cART in retention of immune reconstitution; however, short interruptions did not lead to a greater rate of resistance mutations or adverse events than cART suggesting that this regimen may be more forgiving than NNRTIs if interruptions in therapy occur.
  • Publication
    Early Mortality and AIDS Progression Despite High Initial Antiretroviral Therapy Adherence and Virologic Suppression in Botswana
    (2011-06-15) Steenhoff, Andrew P; Newcomb, Craige W; Steele, Katherine; Bellamy, Scarlett L; Rantleru, Tumelo; Gross, Robert; Nthobatsang, Rudo; Bisson, Gregory P; Lesetedi, Gloria; Nachega, Jean B
    Background Adverse outcomes occurring early after antiretroviral therapy (ART) initiation are common in sub-Saharan Africa, despite reports of high levels of ART adherence in this setting. We sought to determine the relationship between very early ART adherence and early adverse outcomes in HIV-infected adults in Botswana. Methods This prospective cohort study of 402 ART-naïve, HIV-infected adults initiating ART at a public HIV clinic in Gaborone, Botswana evaluated the relationship between suboptimal early ART adherence and HIV treatment outcomes in the initial months after ART initiation. Early adherence during the interval between initial ART dispensation and first ART refill was calculated using pill counts. In the primary analysis patients not returning to refill and those with adherence <0.95 were considered to have suboptimal early adherence. The primary outcome was death or loss to follow-up during the first 6 months of ART; a secondary composite outcome included the primary outcome plus incident opportunistic illness (OIs) and virologic failure. We also calculated the percent of early adverse outcomes theoretically attributable to suboptimal early adherence using the population attributable risk percent (PAR%). Results Suboptimal early adherence was independently associated with loss to follow-up and death (adjusted OR 2.3, 95% CI 1.1–4.8) and with the secondary composite outcome including incident OIs and virologic failure (adjusted OR 2.6, 95% CI 1.4–4.7). However, of those with early adverse outcomes, less than one-third had suboptimal adherence and approximately two-thirds achieved virologic suppression. The PAR% relating suboptimal early adherence and primary and secondary outcomes were 14.7% and 17.7%, respectively. Conclusions Suboptimal early adherence was associated with poor outcomes, but most early adverse outcomes occurred in patients with optimal early adherence. Clinical care and research efforts should focus on understanding early adverse outcomes that occur despite optimal adherence.
  • Publication
    Risk Factors for Suboptimal Antiretroviral Therapy Adherence in HIV-Infected Adolescents in Gaborone, Botswana: A Pilot Cross-Sectional Study
    (2013-09-11) Ndiaye, Maimouna; Nyasulu, Peter; Lowenthal, Elizabeth D; Nguyen, Hoang; Gross, Robert; Mills, Edward J; Nachega, Jean B
    Objective: Little is known about factors associated with suboptimal antiretroviral treatment (ART) adherence among adolescents in Sub-Saharan Africa. Our objective was to determine the level of ART adherence and predictors of non-adherence among human immunodeficiency virus (HIV)-infected adolescents at the Botswana-Baylor Children's Clinical Centre of Excellence in Gaborone, Botswana. Methods: In a cross-sectional study, 82 HIV-infected adolescents receiving ART and their caregivers were administered a structured questionnaire. The patient's clinical information was retrieved from medical records. Outcome measures included excellent pill count ART adherence (>95%) and virologic suppression (HIV viral load <400 copies/mL). Multivariate logistic regression analysis was performed to identify independent predictors of ART non-adherence. Results: The overall median (interquartile range) ART adherence was 99% (96.5–100) (N = 82). Seventy-six percent of adolescents had excellent pill count ART adherence levels and 94% achieved virologic suppression. Male adolescents made up 65% of the non-adherent group (P = 0.02). Those who displayed suboptimal ART adherence were more likely to report having ever missed ART doses due to failure to pick up medication at the pharmacy (30.0% versus 9.7%, P = 0.03). In the multivariate logistic regression model, male sex (odds ratio [OR] 3.29, 95% confidence interval [CI] 1.13–9.54; P = 0.03) was the only factor which was independently associated with suboptimal ART adherence. Conclusions: A high proportion of HIV-infected adolescents studied had excellent ART adherence and virologic suppression, with male adolescents at higher risk of suboptimal adherence than females. Further research to investigate how gender relates to suboptimal adherence may aid in the design of targeted intervention strategies.