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JAMA Internal Medicine | 2013

HIV Infection and the Risk of Acute Myocardial Infarction

Matthew S. Freiberg; Chung Chou H Chang; Lewis H. Kuller; Melissa Skanderson; Elliott Lowy; Kevin L. Kraemer; Adeel A. Butt; Matthew Bidwell Goetz; David E. Leaf; Kris Ann Oursler; David Rimland; Maria C. Rodriguez Barradas; Sheldon T. Brown; Cynthia L. Gibert; Kathy McGinnis; Kristina Crothers; Jason J. Sico; Heidi M. Crane; Alberta Warner; Stephen S. Gottlieb; John S. Gottdiener; Russell P. Tracy; Matthew J. Budoff; Courtney Watson; Kaku A. Armah; Donna Almario Doebler; Kendall Bryant; Amy C. Justice

IMPORTANCE Whether people infected with human immunodeficiency virus (HIV) are at an increased risk of acute myocardial infarction (AMI) compared with uninfected people is not clear. Without demographically and behaviorally similar uninfected comparators and without uniformly measured clinical data on risk factors and fatal and nonfatal AMI events, any potential association between HIV status and AMI may be confounded. OBJECTIVE To investigate whether HIV is associated with an increased risk of AMI after adjustment for all standard Framingham risk factors among a large cohort of HIV-positive and demographically and behaviorally similar (ie, similar prevalence of smoking, alcohol, and cocaine use) uninfected veterans in care. DESIGN AND SETTING Participants in the Veterans Aging Cohort Study Virtual Cohort from April 1, 2003, through December 31, 2009. PARTICIPANTS After eliminating those with baseline cardiovascular disease, we analyzed data on HIV status, age, sex, race/ethnicity, hypertension, diabetes mellitus, dyslipidemia, smoking, hepatitis C infection, body mass index, renal disease, anemia, substance use, CD4 cell count, HIV-1 RNA, antiretroviral therapy, and incidence of AMI. MAIN OUTCOME MEASURE Acute myocardial infarction. RESULTS We analyzed data on 82 459 participants. During a median follow-up of 5.9 years, there were 871 AMI events. Across 3 decades of age, the mean (95% CI) AMI events per 1000 person-years was consistently and significantly higher for HIV-positive compared with uninfected veterans: for those aged 40 to 49 years, 2.0 (1.6-2.4) vs 1.5 (1.3-1.7); for those aged 50 to 59 years, 3.9 (3.3-4.5) vs 2.2 (1.9-2.5); and for those aged 60 to 69 years, 5.0 (3.8-6.7) vs 3.3 (2.6-4.2) (P < .05 for all). After adjusting for Framingham risk factors, comorbidities, and substance use, HIV-positive veterans had an increased risk of incident AMI compared with uninfected veterans (hazard ratio, 1.48; 95% CI, 1.27-1.72). An excess risk remained among those achieving an HIV-1 RNA level less than 500 copies/mL compared with uninfected veterans in time-updated analyses (hazard ratio, 1.39; 95% CI, 1.17-1.66). CONCLUSIONS AND RELEVANCE Infection with HIV is associated with a 50% increased risk of AMI beyond that explained by recognized risk factors.


American Journal of Respiratory and Critical Care Medicine | 2011

HIV Infection and Risk for Incident Pulmonary Diseases in the Combination Antiretroviral Therapy Era

Kristina Crothers; Laurence Huang; Joseph L. Goulet; Matthew Bidwell Goetz; Sheldon T. Brown; Maria C. Rodriguez-Barradas; Krisann K. Oursler; David Rimland; Cynthia L. Gibert; Adeel A. Butt; Amy C. Justice

RATIONALE In aging HIV-infected populations comorbid diseases are important determinants of morbidity and mortality. Pulmonary diseases have not been systematically assessed in the combination antiretroviral therapy (ART) era. OBJECTIVES To determine the incidence of pulmonary diseases in HIV-infected persons compared with HIV-uninfected persons. METHODS We analyzed data from the Veterans Aging Cohort Study Virtual Cohort, consisting of 33,420 HIV-infected veterans and 66,840 age, sex, race and ethnicity, and site-matched HIV-uninfected veterans. Using Poisson regression, incidence rates and adjusted incidence rate ratios were calculated to determine the association of HIV with pulmonary disease. The Virtual Cohort was merged with the 1999 Veterans Large Health Survey to adjust for self-reported smoking in a nested sample (14%). MEASUREMENTS AND MAIN RESULTS Incident chronic obstructive pulmonary disease, lung cancer, pulmonary hypertension, and pulmonary fibrosis, as well as pulmonary infections, were significantly more likely among HIV-infected patients compared with uninfected patients in adjusted analyses, although rates of asthma did not differ by HIV status. Bacterial pneumonia and chronic obstructive pulmonary disease were the two most common incident pulmonary diseases, whereas opportunistic pneumonias were less common. Absolute rates of most pulmonary diseases increased with age, although the relative differences between those with and without HIV infection were greatest in younger persons. Chronic obstructive pulmonary disease and asthma, as well as pulmonary infections, were less likely in those with lower HIV RNA levels and use of ART at baseline. CONCLUSIONS Pulmonary diseases among HIV-infected patients receiving care within the Veterans Affairs Healthcare System in the combination ART era reflect a substantial burden of non-AIDS-defining and chronic conditions, many of which are associated with aging.


Medical Care | 2006

Veterans aging cohort study (VACS) : Overview and description

Amy C. Justice; Elizabeth Dombrowski; Joseph Conigliaro; Shawn L. Fultz; Deborah Gibson; Tamra Madenwald; Joseph L. Goulet; Michael S. Simberkoff; Adeel A. Butt; David Rimland; Maria C. Rodriguez-Barradas; Cynthia L. Gibert; Kris Ann Oursler; Sheldon T. Brown; David A. Leaf; Matthew Bidwell Goetz; Kendall Bryant

Background:The Veterans Aging Cohort Study (VACS) is a study of human immunodeficiency virus (HIV) infected and uninfected patients seen in infectious disease and general medical clinics. VACS includes the earlier 3 and 5 site studies (VACS 3 and VACS 5) as well as the ongoing 8 site study. Objectives:We sought to provide background and context for analyses based upon VACS data, including study design and rationale as well as its basic protocol and the baseline characteristics of the enrolled sample. Research Design:We undertook a prospectively consented multisite observational study of veterans in care with and without HIV infection. Measures:Data were derived from patient and provider self report, telephone interviews, blood and DNA samples, focus groups, and full access to the national VA “paperless” electronic medical record system. Results:More than 7200 veterans have been enrolled in at least one of the studies. The 8 site study (VACS) has enrolled 2979 HIV-infected and 3019 HIV-uninfected age–race–site matched comparators and has achieved stratified enrollment targets for race/ethnicity and age and 99% of its total target enrollment as of October 30, 2005. Participants in VACS are similar to other veterans receiving care within the VA. VACS participants are older and more predominantly black than those reported by the Centers for Disease Control. Conclusions:VACS has assembled a rich, in-depth, and representative sample of veterans in care with and without HIV infection to conduct longitudinal analyses of questions concerning the association between alcohol use and related comorbid and AIDS-defining conditions.


Clinical Infectious Diseases | 2012

HIV status, burden of comorbid disease, and biomarkers of inflammation, altered coagulation, and monocyte activation

Kaku A. Armah; Kathleen A. McGinnis; Jason V. Baker; Cynthia L. Gibert; Adeel A. Butt; Kendall Bryant; Matthew Bidwell Goetz; Russell P. Tracy; Kris Ann Oursler; David Rimland; Kristina Crothers; Maria C. Rodriguez-Barradas; Steve Crystal; Adam J. Gordon; Kevin L. Kraemer; Sheldon T. Brown; Mariana Gerschenson; David A. Leaf; Steven G. Deeks; Charles R. Rinaldo; Lewis H. Kuller; Amy C. Justice; Matthew S. Freiberg

BACKGROUND Biomarkers of inflammation, altered coagulation, and monocyte activation are associated with mortality and cardiovascular disease (CVD) in the general population and among human immunodeficiency virus (HIV)-infected people. We compared biomarkers for inflammation, altered coagulation, and monocyte activation between HIV-infected and uninfected people in the Veterans Aging Cohort Study (VACS). METHODS Biomarkers of inflammation (interleukin-6 [IL-6]), altered coagulation (d-dimer), and monocyte activation (soluble CD14 [sCD14]) were measured in blood samples from 1525 HIV-infected and 843 uninfected VACS participants. Logistic regression was used to determine the association between HIV infection and prevalence of elevated (>75th percentile) biomarkers, adjusting for confounding comorbidities. RESULTS HIV-infected veterans had less prevalent CVD, hypertension, diabetes, obesity, hazardous drinking, and renal disease, but more dyslipidemia, hepatitis C, and current smoking than uninfected veterans. Compared to uninfected veterans, HIV-infected veterans with HIV-1 RNA ≥500 copies/mL or CD4 count <200 cells/µL had a significantly higher prevalence of elevated IL-6 (odds ratio [OR], 1.54; 95% confidence interval [CI],1.14-2.09; OR, 2.25; 95% CI, 1.60-3.16, respectively) and d-dimer (OR, 1.97; 95% CI, 1.44-2.71, OR, 1.68; 95% CI, 1.22-2.32, respectively) after adjusting for comorbidities. HIV-infected veterans with a CD4 cell count <200 cells/µL had significantly higher prevalence of elevated sCD14 compared to uninfected veterans (OR, 2.60; 95% CI, 1.64-4.14). These associations still persisted after restricting the analysis to veterans without known confounding comorbid conditions. CONCLUSIONS These data suggest that ongoing HIV replication and immune depletion significantly contribute to increased prevalence of elevated biomarkers of inflammation, altered coagulation, and monocyte activation. This contribution is independent of and in addition to the substantial contribution from comorbid conditions.


Annals of Internal Medicine | 2014

Hepatic Decompensation in Antiretroviral-Treated Patients Co-Infected With HIV and Hepatitis C Virus Compared With Hepatitis C Virus–Monoinfected Patients: A Cohort Study

Vincent Lo Re; Michael J. Kallan; Janet P. Tate; A. Russell Localio; Joseph K. Lim; Matthew Bidwell Goetz; Marina B. Klein; David Rimland; Maria C. Rodriguez-Barradas; Adeel A. Butt; Cynthia L. Gibert; Sheldon T. Brown; Lesley S. Park; Robert Dubrow; K. Rajender Reddy; Jay R. Kostman; Brian L. Strom; Amy C. Justice

Context Patients with HIV are often co-infected with hepatitis C virus (HCV). Whether treatment of HIV with antiretroviral therapy (ART) can improve HCV outcomes is a topic of interest. Contribution In a Veterans Affairs study, patients co-infected with HIV and HCV who had HIV RNA levels less than 1000 copies/mL had a lower rate of hepatic decompensation than those with less HIV suppression. However, the rate was still higher than that in HCV-monoinfected patients. Caution Few women were studied. Implication Patients co-infected with HIV and HCV remain at greater risk for poor outcomes from HCV infection than HCV-monoinfected patients despite viral suppression by ART. The Editors Co-infection with chronic hepatitis C virus (HCV) occurs in 10% to 30% of HIV-infected patients (14). The course of chronic HCV is accelerated in patients co-infected with HIV, with more rapid progression of liver fibrosis than in HCV-monoinfected patients (57). Consequently, HCV-related liver complications, particularly hepatic decompensation (defined by the presence of ascites, spontaneous bacterial peritonitis, variceal hemorrhage, or hepatic encephalopathy [8]), have emerged as important causes of illness in co-infected patients (9, 10). Despite the importance of HCV-related end-stage liver disease, few longitudinal studies have evaluated the incidence and determinants of hepatic decompensation among patients co-infected with HIV and HCV during the antiretroviral therapy (ART) era. Previous studies suggest that ART slows progression of HCV-associated liver fibrosis, possibly by reducing HIV-related inflammation and immune dysfunction and inhibiting the ability of HIV to directly infect hepatocytes (1013). However, whether rates of hepatic decompensation and other severe liver events (for example, hepatocellular carcinoma [HCC] or liver-related death) in co-infected patients receiving ART are similar to those in HCV-monoinfected patients remains unclear. Furthermore, the determinants of hepatic decompensation among co-infected patients receiving ART are unknown. Determination of these factors could help define the mechanisms of decompensation in co-infected patients and could suggest interventions to reduce the risk for end-stage liver disease in this population. We first compared the incidence of hepatic decompensation between antiretroviral-treated patients co-infected with HIV and HCV and HCV-monoinfected patients. We hypothesized that rates of decompensation would remain higher in co-infected patients despite ART. We then evaluated host and viral factors associated with decompensation among co-infected patients. Methods Study Design and Data Source We conducted a retrospective cohort study among antiretroviral-treated patients co-infected with HIV and HCV and HCV-monoinfected patients in the VACS-VC (Veterans Aging Cohort Study Virtual Cohort) between 1 January 1997 and 30 September 2010 (14). The VACS-VC consists of electronic medical record data from HIV-infected patients receiving care at Veterans Affairs (VA) medical facilities across the United States. Each HIV-infected patient is matched on age, sex, race/ethnicity, and site to 2 HIV-uninfected persons. Data include hospital and outpatient diagnoses (recorded using International Classification of Diseases, Ninth Revision [ICD-9], codes), procedures (recorded using CPT [Current Procedural Terminology] codes), laboratory results, and pharmacy data. Clinically confirmed cancer diagnoses are available from the VA Central Cancer Registry. Deaths are identified from the VA Vital Status file, which uses data from the Social Security Death Master File, Medicare Vital Status Files, and VA Beneficiary Identification and Records Locator Subsystem. For patients who died, principal cause of death can be determined by linkage with the National Death Index (15). In addition, U.S. Medicare and Medicaid claims data are available for veterans also enrolled in these programs and have been merged with VACS-VC data. Study Patients Co-infected patients were included if they had detectable HCV RNA, had recently initiated ART (defined as use of 3 antiretrovirals from 2 classes [16] or 3 nucleoside analogues [a previously accepted ART regimen] [17]) within the VA system, had an HIV RNA level greater than 500 copies/mL within 180 days before starting ART (to identify those who newly initiated ART [18]), and had been observed for at least 12 months in the VACS-VC after starting ART. Monoinfected patients had detectable HCV RNA, no recorded HIV ICD-9 diagnosis or antiretroviral prescriptions, and at least 12 months of observation in the VACS-VC. Patients were excluded if, during the baseline period (defined in the Statistical Analysis section), they had hepatic decompensation, HCC, or liver transplantation or received interferon-based HCV therapy (because treatment reduces the risk for hepatic decompensation [19, 20]). Study Outcomes The primary outcome was incident hepatic decompensation, which was defined by 1 ICD-9 diagnosis of ascites, spontaneous bacterial peritonitis, or esophageal variceal hemorrhage at hospital discharge or 2 such outpatient diagnoses in the VACS-VC (Supplement 1). A prior study validated this determination, with 91% of events confirmed by medical records (21). The requirement of 2 outpatient diagnoses aimed to exclude events that were suspected but not subsequently confirmed at follow-up visits. On the basis of the results of the prior validation study (21), we did not include ICD-9 diagnoses for hepatic encephalopathy and jaundice, which could indicate decompensation, because these diagnoses frequently were linked to unrelated conditions (for example, narcotic overuse, stroke recorded as encephalopathy, or biliary obstruction or atazanavir-associated hyperbilirubinemia recorded as jaundice). Date of decompensation was defined as the hospital discharge date (if identified by hospital diagnosis) or initial outpatient diagnosis date (if identified by outpatient diagnosis). Supplement 1. ICD-9, ICD-10, and CPT Codes Secondary outcomes included incident hepatic decompensation (determined by the aforementioned ICD-9based definition) within the VACS-VC, Medicare, or Medicaid data (to capture outcomes occurring at non-VA hospitals that did not result in transfer to a VA facility; this outcome was secondary because non-VA events have not been validated); HCC; and severe liver events, a composite outcome of hepatic decompensation within the VACS-VC, HCC, or liver-related death. Hepatocellular carcinoma was determined using the VA Central Cancer Registry, which confirmed diagnoses by histologic or cytologic evaluation or consistent radiography. We classified deaths as liver-related if the underlying cause from the National Death Index was recorded as hepatic decompensation, liver cancer, alcoholic liver disease, viral hepatitis, or nonalcoholic liver disease (Supplement 1) (15). Data Collection Baseline data (Table 1) included age, sex, race/ethnicity, VA center patient volume, body mass index (BMI), diabetes mellitus, alcohol dependence or abuse, injection or noninjection drug use, hepatitis B surface antigen status, HCV genotype, HCV RNA level, pre-ART CD4 cell count, pre-ART plasma HIV RNA level, and baseline antiretroviral regimen. Diabetes was defined as a random glucose level of at least 200 mg/dL or antidiabetic medication use (22, 23). Alcohol dependence or abuse (24) and injection or noninjection drug use (24, 25) were defined by previously validated ICD-9 diagnoses (Supplement 1). Baseline serum creatinine, hemoglobin, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels and platelet count were collected from dates closest to but before the start of follow-up. Baseline FIB-4 score, a noninvasive measure of advanced hepatic fibrosis, was determined as follows: [age in yearsAST level in U/L] / [(platelet count in109/L)(ALT level in U/L)1/2] (26). Because liver fibrosis can progress by 1 stage as early as within 4 years for antiretroviral-treated patients co-infected with HIV and HCV (7) and within 5 years for HCV-monoinfected persons (27), we determined baseline FIB-4 scores by using ALT levels, AST levels, and platelet counts within a 2-year period around the start of follow-up. Scores less than 1.45 indicate no or minimal fibrosis, and scores greater than 3.25 indicate advanced hepatic fibrosis or cirrhosis in co-infected (26) and HCV-monoinfected patients (28). Table 1. Characteristics of the Study Cohorts Longitudinal data included hepatitis B surface antigen status, plasma HIV RNA level, diabetes, and liver transplantation (determined by diagnosis and procedural codes) (Supplement 1). Statistical Analysis The 12 months before the start of follow-up represented the baseline period for both cohorts. Follow-up began 12 months after ART initiation for co-infected patients and after 12 months in the VACS-VC for monoinfected patients. The rationale for defining the baseline period as the first year of receipt of ART for co-infected patients was that many of these patients initially entered care at the time of ART initiation, which was shortly after their HIV diagnosis. Follow-up continued until a study end point, death, initiation of HCV therapy, or the last visit before 30 September 2010, whichever came first. For descriptive purposes, we estimated incidence rates (events per 1000 person-years) of end points with 95% CIs, standardized by the age and race/ethnicity distribution of co-infected patients (29). We then used Cox models to estimate adjusted hazard ratios (HRs) for outcomes in co-infected compared with monoinfected patients (30). We controlled for all available clinically relevant variables in Table 1. The proportionality of hazards was evaluated by plots of Schoenfeld residuals (31). In a sensitivity analysis, we addressed the potential for informative censoring by using inverse probability of censoring weights and Cox regression (Supplement


Hiv Medicine | 2010

Towards a combined prognostic index for survival in HIV infection: the role of 'non-HIV' biomarkers

Amy C. Justice; Kathleen A. McGinnis; Melissa Skanderson; Chung Chou H Chang; Cynthia L. Gibert; Matthew Bidwell Goetz; David Rimland; Maria C. Rodriguez-Barradas; Krisann K. Oursler; Sheldon T. Brown; Rs Braithwaite; Margaret T May; Kenneth E. Covinsky; Roberts; Sl Fultz; Kendall Bryant

As those with HIV infection live longer, ‘non‐AIDS’ condition associated with immunodeficiency and chronic inflammation are more common. We ask whether ‘non‐HIV’ biomarkers improve differentiation of mortality risk among individuals initiating combination antiretroviral therapy (cART).


AIDS | 2004

Psychiatric and neurocognitive disorders among HIV-positive and negative veterans in care: Veterans Aging Cohort five-site Study

Amy C. Justice; Kathleen A. McGinnis; Atkinson Jh; Robert K. Heaton; Corinna Young; Joseph Sadek; Tamra Madenwald; Becker Jt; Joseph Conigliaro; Sheldon T. Brown; David Rimland; Stephen Crystal; Michael S. Simberkoff

Background: The risk for psychiatric and neurocognitive disorders among middle-aged and older individuals with HIV infection has not been well characterized. Methods: The Veterans Aging Cohort 5-Site Study enrolled 1803 patients (1047 HIV-positive) from VA infectious disease and general medicine clinics from September 2001 to June 2002. A convenience subset of 10 patients from each site (n = 50) was consented for formal neurocognitive and psychiatric (NCP) testing. Data from this subset were linked to the larger sample. Results: Kappa scores for agreement beyond chance were fair for available measures when compared with formal NCP testing. Using available measures, depressive symptoms (PHQ-9 and provider reported), alcohol abuse or dependence (ICD-9 codes), and drug abuse or dependence (DAST-10) decreased with age in HIV-negative subjects (P trend <0.05) but did not among HIV-positive subjects (P > 0.05). HIV-positive subjects demonstrated higher prevalence of these conditions with increasing age when compared to HIV-negative subjects. Patient report of memory problems increased with age among both groups after excluding those reporting symptoms of depression (PHQ-9e ⩾ 10). Conclusion: Available measures were no substitute for formal NCP testing. Older HIV-positive veterans demonstrate greater prevalence of depressive symptoms, alcohol abuse or dependence, and drug abuse or dependence than age-matched, HIV-negative veterans. Both groups reported increased memory problems with advancing age. This preliminary work suggests a substantial prevalence of psychiatric and neurocognitive problems among middle-aged and older HIV-infected individuals.


Clinical Infectious Diseases | 2013

Escherichia coli Sequence Type 131 (ST131) Subclone H30 as an Emergent Multidrug-Resistant Pathogen Among US Veterans

Aylin Colpan; Brian Johnston; Stephen Porter; Connie Clabots; Ruth Anway; Lao Thao; Michael A. Kuskowski; Veronika Tchesnokova; Evgeni V. Sokurenko; James R. Johnson; Bradley L. Allen; Gio J. Baracco; Roger Bedimo; Mary T. Bessesen; Robert A. Bonomo; Stephen M. Brecher; Sheldon T. Brown; Laila Castellino; Arundhati S. Desai; Fletcher Fernau; Mark A. Fisher; James Fleckenstein; Carol S. Fleming; Narla J. Fries; Virginia L. Kan; Carol A. Kauffman; Stacey Klutts; Michael Ohl; Thomas A. Russo; Andrea Swiatlo

BACKGROUND Escherichia coli sequence type 131 (ST131), typically fluoroquinolone-resistant (FQ-R) and/or extended-spectrum β-lactamase (ESBL)-producing, has emerged globally. We assessed its prevalence and characteristics among US veterans. METHODS In 2011, 595 de-identified E. coli clinical isolates were collected systematically within 3 resistance groups (FQ-susceptible [FQ-S], FQ-R, and ESBL-producing) from 24 nationally distributed Veterans Affairs Medical Centers (VAMCs). ST131 and its H30 subclone were detected by polymerase chain reaction and compared with other E. coli for molecular traits, source, and resistance profiles. RESULTS ST131 accounted for 78% (184/236) of FQ-R and 64.2% (79/123) of ESBL-producing isolates, but only 7.2% (17/236) of FQ-S isolates (P < .001). The H30 subclone accounted for ≥95% of FQ-R and ESBL-producing, but only 12.5% of FQ-S, ST131 isolates (P < .001). By back-calculation, 28% of VAMC E. coli isolates nationally represented ST131. Overall, ST131 varied minimally in prevalence by specimen type, inpatient/outpatient source, or locale; was the most prevalent ST, followed distantly by ST95 and ST12 (13% each); and accounted for ≥40% (β-lactams), >50% (trimethoprim-sulfamethoxazole , multidrug), or >70% (ciprofloxacin, gentamicin) of total antimicrobial resistance. FQ-R and ESBL-producing ST131 isolates had higher virulence scores than corresponding non-ST131 isolates. ST131 pulsotypes overlapped extensively among VAMCs. CONCLUSIONS Among US veterans, ST131, primarily its H30 subclone, accounts for most antimicrobial-resistant E. coli and is the dominant E. coli strain overall. Possible contributors include multidrug resistance, extensive virulence gene content, and ongoing transmission. Focused attention to ST131, especially its H30 subclone, could reduce infection-related morbidity, mortality, and costs among veterans.


Nucleic Acids Research | 2012

Ultrasensitive detection of rare mutations using next-generation targeted resequencing

Patrick Flaherty; Georges Natsoulis; Omkar Muralidharan; Mark A. Winters; Jason D. Buenrostro; John M. Bell; Sheldon T. Brown; Mark Holodniy; Nancy Zhang; Hanlee P. Ji

With next-generation DNA sequencing technologies, one can interrogate a specific genomic region of interest at very high depth of coverage and identify less prevalent, rare mutations in heterogeneous clinical samples. However, the mutation detection levels are limited by the error rate of the sequencing technology as well as by the availability of variant-calling algorithms with high statistical power and low false positive rates. We demonstrate that we can robustly detect mutations at 0.1% fractional representation. This represents accurate detection of one mutant per every 1000 wild-type alleles. To achieve this sensitive level of mutation detection, we integrate a high accuracy indexing strategy and reference replication for estimating sequencing error variance. We employ a statistical model to estimate the error rate at each position of the reference and to quantify the fraction of variant base in the sample. Our method is highly specific (99%) and sensitive (100%) when applied to a known 0.1% sample fraction admixture of two synthetic DNA samples to validate our method. As a clinical application of this method, we analyzed nine clinical samples of H1N1 influenza A and detected an oseltamivir (antiviral therapy) resistance mutation in the H1N1 neuraminidase gene at a sample fraction of 0.18%.


AIDS | 2012

HIV as an Independent Risk Factor for Incident Lung Cancer

Keith Sigel; Juan P. Wisnivesky; Kirsha Gordon; Robert Dubrow; Amy C. Justice; Sheldon T. Brown; Joseph L. Goulet; Adeel A. Butt; Stephen Crystal; David Rimland; Maria C. Rodriguez-Barradas; Cynthia L. Gibert; Lesley S. Park; Kristina Crothers

Background:It is unclear whether the elevated rate of lung cancer among HIV-infected persons is due to biological effects of HIV, surveillance bias, or excess smoking. We compared the incidence of lung cancer between HIV-infected and demographically similar HIV-uninfected patients, accounting for smoking and stage of lung cancer at diagnosis. Design:Data from the Veterans Aging Cohort Study Virtual Cohort were linked to data from the Veterans Affairs Central Cancer Registry, resulting in an analytic cohort of 37 294 HIV-infected patients and 75 750 uninfected patients. Methods:We calculated incidence rates of pathologically confirmed lung cancer by dividing numbers of cases by numbers of person-years at risk. We used Poisson regression to determine incidence rate ratios (IRRs), adjusting for age, sex, race/ethnicity, smoking prevalence, previous bacterial pneumonia, and chronic obstructive pulmonary disease. Results:The incidence rate of lung cancer in HIV-infected patients was 204 cases per 100 000 person-years [95% confidence interval (CI) 167–249] and among uninfected patients was 119 cases per 100 000 person-years (95% CI 110–129). The IRR of lung cancer associated with HIV infection remained significant after multivariable adjustment (IRR 1.7; 95% CI 1.5–1.9). Lung cancer stage at presentation did not differ between HIV-infected and uninfected patients. Conclusion:In our cohort of demographically similar HIV-infected and uninfected patients, HIV infection was an independent risk factor for lung cancer after controlling for potential confounders including smoking. The similar stage distribution between the two groups indicated that surveillance bias was an unlikely explanation for this finding.

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Cynthia L. Gibert

George Washington University

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Adeel A. Butt

Hamad Medical Corporation

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Robert J. Greenstein

Icahn School of Medicine at Mount Sinai

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