Kathy Wood

Protease inhibitors and cardiovascular outcomes in patients with HIV-1

Protease inhibitors for treatment of HIV-1 have been linked with increased risk of hyperlipidaemia and hyperglycaemia. In a cohort of 5672 outpatients with HIV-1 seen at nine US HIV clinics between January, 1993, and January, 2002, the frequency of myocardial infarctions increased after the introduction of protease inhibitors in 1996 (test for trend, p=0.0125). We noted that 19 of 3247 patients taking, but only two of 2425 who did not take, protease inhibitors had a myocardial infarction (odds ratio 7.1, 95% CI 1.6-44.3; Cox proportional hazards model-adjusted for smoking, sex, age, diabetes, hyperlipidaemia, and hypertension-hazard ratio 6.5, 0.9-47.8). Our findings suggest that, although infrequent, use of protease inhibitors is associated with increased risk of myocardial infarction in patients with HIV-1.

Low CD4+ T Cell Count Is a Risk Factor for Cardiovascular Disease Events in the HIV Outpatient Study

BACKGROUND Traditional cardiovascular disease (CVD) risk factors, human immunodeficiency virus (HIV) infection, and antiretroviral (ARV) agents have been associated with CVD events in HIV-infected patients. We investigated the association of low CD4(+) T lymphocyte cell count with incident CVD in a cohort of outpatients treated in 10 HIV specialty clinics in the United States. METHODS We studied patients who were under observation from 1 January 2002 (baseline), categorized them according to National Cholesterol Education Program guidelines into 10-year cardiovascular risk score (10-y CVR) groups , and observed them until CVD event, death, last HIV Outpatient Study contact, or 30 September 2009. We calculated rates of incident CVD events and identified associated baseline risk factors using Cox proportional hazard models. We also performed a nested case-control study to examine the association of latest CD4(+) cell count with CVD events. RESULTS Among 2005 patients, 148 experienced incident CVD events. CVD incidence increased steadily from 0.4 to 3.0 events per 100 person-years from lowest to highest 10-y CVR group (P < .001). In multivariable Cox analyses adjusted for 10-y CVR, CD4(+) cell count <350 cells/mm(3) was associated with incident CVD events (hazard ratio, 1.58 [95% confidence interval, 1.09-2.30], compared with >500 cells/mm(3)), suggesting an attributable risk of approximately 20%. In the multivariable case-control analyses, traditional CVD risk factors and latest CD4(+) cell count <500 cells/mm(3), but not cumulative use of ARV class or individual drugs, were associated with higher odds of experiencing CVD events. CONCLUSION CD4(+) count <500 cells/mm(3) is an independent risk factor for incident CVD, comparable in attributable risk to several traditional CVD risk factors in the HIV Outpatient Study cohort.

Protease inhibitor exposure and increased risk of cardiovascular disease in HIV-infected patients.

To study the relationship between exposure to protease inhibitor (PI) therapy and increased risk of cardiovascular events in HIV‐infected patients.

Ongoing sexually transmitted disease acquisition and risk-taking behavior among US HIV-infected patients in primary care: implications for prevention interventions.

Background: To better understand the factors associated with HIV- and sexually transmitted disease (STD)-transmitting behavior among HIV-infected persons, we estimated STD prevalence and incidence and associated risk factors among a diverse sample of HIV-infected patients in primary care. Methods: We analyzed data from 557 participants in the SUN Study, a prospective observational cohort of HIV-infected adults in primary care in 4 US cities. At enrollment and 6 months thereafter, participants completed an audio computer-assisted self-interview about their sexual behavior, and were screened for genitourinary, rectal, and pharyngeal Neisseria gonorrhoeae and Chlamydia trachomatis infections by nucleic acid amplification testing, and for serologic evidence of syphilis. Women provided cervicovaginal samples and men provided urine to screen for Trichomonas vaginalis by polymerase chain reaction. Results: Thirteen percent of participants had a prevalent STD at enrollment and 7% an incident STD 6 months later. The most commonly diagnosed infections were rectal chlamydia, oropharyngeal gonorrhea, and chlamydial urethritis among the men and trichomoniasis among the women. Other than trichomoniasis, 94% of incident STDs were identified in men who have sex with men. Polysubstance abuse other than marijuana, and having ≥4 sex partners in the 6 months before testing were associated with diagnosis of an incident STD. Conclusions: STDs were commonly diagnosed among contemporary HIV-infected patients receiving routine outpatient care, particularly among sexually active men who have sex with men who used recreational drugs. These findings underscore the need for frequent STD screening, prevention counseling, and substance abuse treatment for HIV-infected persons in care.

Initiation of HAART at higher CD4 cell counts is associated with a lower frequency of antiretroviral drug resistance mutations at virologic failure

Background:There are limited data on the risk of developing HIV drug resistance based on the CD4 cell count at which highly active antiretroviral therapy (HAART) is initiated. Methods:We examined data from participants in the HIV Outpatient Study who initiated antiretroviral therapy with HAART in 1999 or later (when genotypic resistance testing became more commonly used in clinical practice and in the HIV Outpatient Study), achieved virologic suppression, and subsequently experienced virologic failure and received a genotypic assay for antiretroviral resistance mutations. We assessed the frequency of resistance mutations at virologic failure and the differences in the frequencies of mutations by the CD4 stratum at which HAART was initiated using the Cochran-Armitage exact test. Results:Of 683 patients who achieved virologic suppression on a first HAART regimen, 243 had virologic failure and 78 of these had a genotype resistance test done. Among these patients, the frequency of any HIV resistance mutations was 50% among patients who started HAART at 0-199 CD4 cells per cubic millimeter or 200-349 CD4 cells per cubic millimeter compared with 22% among patients who started HAART at ≥350 CD4 cells per cubic millimeter (P = 0.062). The frequency of nucleoside reverse transcriptase inhibitor-associated mutations was 48%, 31%, and 11% among persons who initiated nucleoside reverse transcriptase inhibitor-containing HAART within these respective CD4 cell count strata (P = 0.005). We observed similar trends for nonnucleoside reverse transcriptase inhibitor-associated (P = 0.040) and protease inhibitor-associated (P = 0.063) mutations among persons initiating HAART containing these agents. Conclusions:Patients failing HAART that was initiated at <350 CD4 cells per cubic millimeter had higher frequencies of resistance mutations to the classes of antiretrovirals to which they had been exposed than failing patients who initiated at ≥350 CD4 cells per cubic millimeter. Initiating HAART at higher CD4 cell counts may decrease the risk of developing treatment-limiting antiretroviral resistance.

The Study to Understand the Natural History of HIV and AIDS in the Era of Effective Therapy (SUN Study)

Treatment of human immunodeficiency virus (HIV) infection with highly active combination antiretroviral therapy has increased survival and shifted the spectrum of HIV-associated morbidity and mortality from opportunistic infections toward a variety of other medical conditions. The prospective cohort Study to Understand the Natural History of HIV and AIDS in the Era of Effective Therapy (SUN Study) monitors the clinical course of HIV-infected individuals treated with combination antiretroviral therapy in 4 US cities. Every 6 months, clinical assessments, medical record abstraction, audio computer-assisted self-interview, and neurocognitive measurements are completed and blood and urine specimens are banked centrally. At enrollment and periodically thereafter, additional techniques such as anal cytology, dual energy x-ray absorptiometry, carotid ultrasonography, echocardiography, and abdominal and cardiac computed tomography are performed. From March 2004 through June 2006, 700 participants were enrolled; median age was 41 years, 76% were men, 58% were non-Hispanic white, 62% were men who have sex with men, 78% were taking combination antiretroviral therapy (of whom 86% had an HIV viral load of <400 copies/mL), and median CD4+ T-lymphocyte count was 459 cells/mm(3) (interquartile range: 324-660). The SUN Study provides a wealth of data that will inform and improve the clinical management of HIV-infected individuals in the modern era.

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 log10 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/&mgr;l, respectively; median viral load was 2.7 log10 copies/ml. The most common IRIS-defining diagnoses were candidiasis (all forms), cytomegalovirus infection, disseminated Mycobacterium avium intracellulare, Pneumocystis pneumonia, varicella zoster, Kaposis 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/&mgr;l vs. at least 200 cells/&mgr;l [odds ratio (OR) 5.0] and a viral load of at least 5.0 log10 copies vs. less than 4.0 log10 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.

Renal Function in Tenofovir-Exposed and Tenofovir-Unexposed Patients Receiving Highly Active Antiretroviral Therapy in the HIV Outpatient Study

Background: Cases of renal dysfunction have been reported in HIV-infected patients taking tenofovir (TDF), but few large studies have examined population-level changes in renal function associated with TDF use in patients in routine care. Methods: The authors analyzed data from participants in the HIV Outpatient Study (HOPS) who had normal baseline renal function and received >1 month of TDF-containing (n = 593) or TDF-sparing (n = 521) HAART after November 1, 2001. Results: Median baseline CrCl estimated by Cockcroft-Gault equation was 106 mL/min for TDF-exposed and 110 mL/min for TDF-unexposed patients (P = 0.06). In multivariable analyses, 1-year changes in CrCl (mL/min) from baseline were —5.7 among TDF-exposed and 2.6 among TDF-unexposed (P < 0.001). Incident renal disease was diagnosed in 7 TDF-exposed and 3 TDF-unexposed patients. Conclusions: In this large cohort of HIV-infected outpatients, use of TDF-containing HAART was associated with modest decreases in CrCl during the first year, but not with frequent, clinically significant renal toxicity.

Factors associated with non-adherence to antiretroviral therapy in the SUN study

Abstract Background. Adherence of 95% or greater to highly active combination antiretroviral therapy is generally considered necessary to achieve optimal virologic suppression in HIV-infected patients. Understanding factors associated with poor adherence is essential to improve patient compliance, maximize virologic suppression, and reduce morbidity and mortality. Methods. We evaluated baseline data from 528 patients taking antiretrovirals, enrolled from March 2004 to June 2006, in a multicenter, longitudinal, prospective cohort study (the SUN study). Using multiple logistic regression, we examined independent risk factors for non-adherence, defined as reporting having missed one or more antiretroviral doses in the past three days on the baseline questionnaire. Results. Of 528 participants (22% female, 28% black, median age 41 years, and median CD4 cell count 486 cells/mm3), 85 (16%) were non-adherent. In the final parsimonious multivariate model, factors independently associated with non-adherence included black race (adjusted odds ratio (aOR): 2.08, 95% confidence interval (CI): 1.20–3.60 vs. white race), being unemployed and looking for work (aOR: 2.03, 95% CI: 1.14–3.61 vs. all other employment categories), having been diagnosed with HIV ≥5 years ago (aOR: 1.95, 95% CI: 1.18–3.24 vs. being HIV-diagnosed <5 years ago), drinking three or more drinks per day (aOR: 1.73, 95% CI: 1.02–2.91 vs. drinking <3 drinks per day), and having not engaged in any aerobic exercise in the last 30 days (aOR: 2.13, 95% CI: 1.25–3.57). Conclusion. Although the above factors may not be causally related to non-adherence, they might serve as proxies for identifying HIV-infected patients at greatest risk for non-adherence who may benefit from additional adherence support.

Renal Function in Patients with Preexisting Renal Disease Receiving Tenofovir-Containing Highly Active Antiretroviral Therapy in the HIV Outpatient Study

Few data exist on the safety of tenofovir (TDF) in HIV-infected patients with preexisting renal dysfunction. We report 12-month changes in renal profiles among 19 such patients (6 patients with history of and 13 patients with current renal disease) in the HIV Outpatient Study (HOPS) who initiated TDF-containing highly active antiretroviral therapy (HAART) during 2001-2005 with TDF dosed mostly at 300 mg once daily. At baseline, the median estimated glomerular filtration rate (GFR) was 49 mL/min/1.73 m(2) and the median CD4(+) cell count was 322 cells/mm(3). Patients had a median 12-month change in estimated creatinine clearance from baseline of -0.3 mL/min (range, -32.2 to +23.6) and the median change in GFR of -0.1 mL/min/1.73 m(2) (range, -49.8 to +29.5). We observed confirmed worsening of kidney disease stage in 5 of the 19 patients during follow-up. TDF use can be considered in patients with preexisting or current renal dysfunction who have limited antiretroviral treatment options, require TDF for fully active antiretroviral regimen, and can be closely monitored for incident worsening of renal function.