Search tips
Search criteria

Results 1-25 (45)

Clipboard (0)

Select a Filter Below

more »
Year of Publication
more »
Document Types
1.  CD8+ T-Cells Count in Acute Myocardial Infarction in HIV Disease in a Predominantly Male Cohort 
BioMed Research International  2015;2015:246870.
Human Immunodeficiency Virus- (HIV-) infected persons have a higher risk for acute myocardial infarction (AMI) than HIV-uninfected persons. Earlier studies suggest that HIV viral load, CD4+ T-cell count, and antiretroviral therapy are associated with cardiovascular disease (CVD) risk. Whether CD8+ T-cell count is associated with CVD risk is not clear. We investigated the association between CD8+ T-cell count and incident AMI in a cohort of 73,398 people (of which 97.3% were men) enrolled in the U.S. Veterans Aging Cohort Study-Virtual Cohort (VACS-VC). Compared to uninfected people, HIV-infected people with high baseline CD8+ T-cell counts (>1065 cells/mm3) had increased AMI risk (adjusted HR = 1.82, P < 0.001, 95% CI: 1.46 to 2.28). There was evidence that the effect of CD8+ T-cell tertiles on AMI risk differed by CD4+ T-cell level: compared to uninfected people, HIV-infected people with CD4+ T-cell counts ≥200 cells/mm3 had increased AMI risk with high CD8+ T-cell count, while those with CD4+ T-cell counts <200 cells/mm3 had increased AMI risk with low CD8+ T-cell count. CD8+ T-cell counts may add additional AMI risk stratification information beyond that provided by CD4+ T-cell counts alone.
PMCID: PMC4320893
2.  Cancer Incidence in HIV-Infected Versus Uninfected Veterans: Comparison of Cancer Registry and ICD-9 Code Diagnoses 
Given the growing interest in the cancer burden in persons living with HIV/AIDS, we examined the validity of data sources for cancer diagnoses (cancer registry versus International Classification of Diseases, Ninth Revision [ICD-9 codes]) and compared the association between HIV status and cancer risk using each data source in the Veterans Aging Cohort Study (VACS), a prospective cohort of HIV-infected and uninfected veterans from 1996 to 2008.
We reviewed charts to confirm potential incident cancers at four VACS sites. In the entire cohort, we calculated cancer-type-specific age-, sex-, race/ethnicity-, and calendar-period-standardized incidence rates and incidence rate ratios (IRR) (HIV-infected versus uninfected). We calculated standardized incidence ratios (SIR) to compare VACS and Surveillance, Epidemiology, and End Results rates.
Compared to chart review, both Veterans Affairs Central Cancer Registry (VACCR) and ICD-9 diagnoses had approximately 90% sensitivity; however, VACCR had higher positive predictive value (96% versus 63%). There were 6,010 VACCR and 13,386 ICD-9 incident cancers among 116,072 veterans. Although ICD-9 rates tended to be double VACCR rates, most IRRs were in the same direction and of similar magnitude, regardless of data source. Using either source, all cancers combined, most viral-infection-related cancers, lung cancer, melanoma, and leukemia had significantly elevated IRRs. Using ICD-9, eight additional IRRs were significantly elevated, most likely due to false positive diagnoses. Most ICD-9 SIRs were significantly elevated and all were higher than the corresponding VACCR SIR.
ICD-9 may be used with caution for estimating IRRs, but should be avoided when estimating incidence or SIRs. Elevated cancer risk based on VACCR diagnoses among HIV-infected veterans was consistent with other studies.
PMCID: PMC4285627  PMID: 25580366
Neoplasms; Registries; International Classification of Diseases; HIV Infections
3.  Medical ICU Admission Diagnoses and Outcomes in Human Immunodeficiency Virus–Infected and Virus–Uninfected Veterans in the Combination Antiretroviral Era 
Critical care medicine  2013;41(6):1458-1467.
Human immunodeficiency virus (HIV)–infected (HIV+) patients on combination antiretroviral therapy are living longer but have increased risk for aging-associated disease which may lead to increasing critical care requirements. We compare medical ICU admission characteristics and outcomes among HIV infected and demographically similar uninfected patients (uninfected) and considered whether an index which combines routine clinical biomarkers (the Veterans Aging Cohort Study Index) predicts 30-day medical ICU mortality.
Observational data analyses (Veterans Aging Cohort Study).
Eight Veterans Affairs medical centers nationwide.
HIV infected and uninfected with a medical ICU admission between 2002 and 2010.
Measurements and Main Results
Medical ICU admission was determined using bedsection (Veterans Affairs) and revenue center codes (Medicare). For Veterans Affairs admissions, we used clinical data to calculate Veterans Aging Cohort Study Index scores and multivariable logistic regression to determine factors associated with 30-day mortality. Overall, 539 of 3,620 (15%) HIV infected and 375 of 3,639 (10%) uninfected had a medical ICU admission; 72% and 78%, respectively, were Veterans Affairs based. HIV+ patients were younger at admission (p < 0.0001). Although most HIV+ patients were on antiretroviral therapy (71%) with undetectable HIV-1 RNA (54%), compared with uninfected they were more commonly admitted with respiratory diagnoses or infections (21% vs. 12%), were more likely to require mechanical ventilation (17% vs. 9%; p = 0.001), and had a higher mortality rate (18.6% vs. 11.2%, p = 0.003). Cardiovascular diagnoses were less common among HIV infected (18% vs. 29%; p < 0.0001). In logistic regression (c-statistic 0.87), a 5-point increment in Veterans Aging Cohort Study Index was associated with an odds ratio of death of 1.22 (95% confidence interval 1.14–1.30) among HIV infected and of 1.50 (95% confidence interval 1.29–1.76) among uninfected; infection/sepsis and respiratory diagnoses were also associated with mortality.
Medical ICU admission was frequent, 30-day mortality higher, and mechanical ventilation more common in HIV infected compared with uninfected. The Veterans Aging Cohort Study Index calculated at medical ICU admission predicted 30-day mortality for HIV infected and uninfected. As more individuals age with HIV, their requirements for medical ICU care may be greater than demographically similar uninfected individuals.
PMCID: PMC4283206  PMID: 23507717
30-day mortality; comorbidity; human immunodeficiency virus; medical ICU; Veterans Aging Cohort Study Index
4.  Prehypertension, Hypertension, and the Risk of Acute Myocardial Infarction in HIV-Infected and -Uninfected Veterans 
We found increased acute myocardial infarction risk among hypertensive and prehypertensive HIV-infected veterans compared to normotensive uninfected veterans, independent of confounding comorbidities.
Background. Compared to uninfected people, human immunodeficiency virus (HIV)–infected individuals may have an increased risk of acute myocardial infarction (AMI). Currently, HIV-infected people are treated to the same blood pressure (BP) goals (<140/90 or <130/80 mm Hg) as their uninfected counterparts. Whether HIV-infected people with elevated BP have excess AMI risk compared to uninfected people is not known. This study examines whether the association between elevated BP and AMI risk differs by HIV status.
Methods. The Veterans Aging Cohort Study Virtual Cohort (VACS VC) consists of HIV-infected and -uninfected veterans matched 1:2 on age, sex, race/ethnicity, and clinical site. For this analysis, we analyzed 81 026 people with available BP data from VACS VC, who were free of cardiovascular disease at baseline. BP was the average of the 3 routine outpatient clinical measurements performed closest to baseline (first clinical visit after April 2003). BP categories used in the analyses were based on criteria of the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. Analyses were performed using Cox proportional hazards regression.
Results. Over 5.9 years (median), 860 incident AMIs occurred. Low/high prehypertensive and untreated/treated hypertensive HIV-infected individuals had increased AMI risk compared to uninfected, untreated normotensive individuals (hazard ratio [HR], 1.60 [95% confidence interval {CI}, 1.07–2.39]; HR, 1.81 [95% CI, 1.22–2.68]; HR, 2.57 [95% CI, 1.76–3.76]; and HR, 2.76 [95% CI, 1.90–4.02], respectively).
Conclusions. HIV, prehypertensive BP, and hypertensive BP were associated with an increased risk of AMI in a cohort of HIV-infected and -uninfected veterans. Future studies should prospectively investigate whether HIV interacts with BP to further increase AMI risk.
PMCID: PMC3864500  PMID: 24065316
blood pressure; prehypertension; HIV; myocardial infarction
5.  Hepatic Decompensation in Antiretroviral-Treated HIV/Hepatitis C-Coinfected Compared to Hepatitis C-Monoinfected Patients: A Cohort Study 
Annals of internal medicine  2014;160(6):369-379.
The incidence and determinants of hepatic decompensation have been incompletely examined among HIV/hepatitis C virus (HCV)-coinfected patients in the antiretroviral therapy (ART) era, and few studies have compared rates of outcomes to those of patients with chronic HCV alone.
To compare the incidence of hepatic decompensation between antiretroviral-treated HIV/HCV-coinfected and HCV-monoinfected patients, and evaluate factors associated with decompensation among coinfected patients on ART.
Retrospective cohort study.
Veterans Health Administration.
4,280 HIV/HCV-coinfected patients who initiated ART and 6,079 HCV-monoinfected patients receiving care between 1997 and 2010. All patients had detectable HCV RNA and were HCV treatment-naïve.
Incident hepatic decompensation, determined by diagnoses of ascites, spontaneous bacterial peritonitis, or esophageal variceal hemorrhage.
The incidence of hepatic decompensation was greater among coinfected than monoinfected patients (at 10 years: 7.4% versus 4.8%; p<0.001). Compared to HCV-monoinfected patients, antiretroviral-treated HIV/HCV-coinfected patients had a higher rate of hepatic decompensation (hazard ratio [HR] accounting for competing risks, 1.56 [95% confidence interval (CI), 1.31–1.86]). Coinfected patients who maintained HIV RNA levels <1,000 copies/mL still had higher rates of decompensation than HCV-monoinfected patients (HR, 1.44 [95% CI, 1.05–1.99]). Baseline advanced hepatic fibrosis (FIB-4 >3.25; HR, 5.45 [95% CI, 3.79–7.84]), baseline hemoglobin <10 g/dL (HR, 2.24 [CI, 1.20–4.20]), diabetes mellitus (HR, 1.88[95% CI, 1.38–2.56]), and non-black race (HR, 2.12 [95% CI, 1.65–2.72]) were each associated with higher rates of decompensation among coinfected patients on ART.
Observational study of predominantly male patients.
Despite ART, HIV/HCV-coinfected patients had higher rates of hepatic decompensation than HCV-monoinfected individuals. Rates of decompensation were higher for coinfected patients with advanced liver fibrosis, severe anemia, diabetes, and non-black race.
PMCID: PMC4254786  PMID: 24723077
hepatic decompensation; end-stage liver disease; HIV/HCV coinfection; HIV; hepatitis C
6.  Risk factors for hospitalization and medical intensive care unit (MICU) admission among HIV infected Veterans 
With improved survival of HIV-infected persons on antiretroviral therapy and growing prevalence of non-AIDS diseases, we asked whether the VACS Index, a composite measure of HIV-associated and general organ dysfunction predictive of all-cause mortality, predicts hospitalization and medical intensive care unit (MICU) admission. We also asked whether AIDS and non-AIDS conditions increased risk after accounting for VACS Index score.
We analyzed data from the Veterans Aging Cohort Study (VACS), a prospective study of HIV-infected Veterans receiving care between 2002–2008. Data were obtained from the electronic medical record, VA administrative databases and patient questionnaires, and were used to identify comorbidities and calculate baseline VACS Index scores. The primary outcome was first hospitalization within 2 years of VACS enrollment. We used multivariable Cox regression to determine risk factors associated with hospitalization and logistic regression to determine risk factors for MICU admission, given hospitalization.
1141/3410 (33.5%) patients were hospitalized within 2 years; 203/1141 (17.8%) included a MICU admission. Median VACS Index scores were 25 (no hospitalization), 34 (hospitalization only) and 51 (MICU). In adjusted analyses, a 5-point increment in VACS Index score was associated with 10% higher risk of hospitalization and MICU admission. In addition to VACS Index score, Hispanic ethnicity, current smoking, hazardous alcohol use, chronic obstructive pulmonary disease, hypertension, diabetes and prior AIDS-defining event predicted hospitalization. Among those hospitalized, VACS Index score, cardiac disease and prior cancer predicted MICU admission.
The VACS Index predicted hospitalization and MICU admission as did current smoking, hazardous alcohol use, and AIDS and certain non-AIDS diagnoses.
PMCID: PMC4182723  PMID: 23111572
HIV; hospitalization; medical intensive care unit (MICU); aging; VACS Index; comorbidity
7.  Validation of an Algorithm to Identify Antiretroviral-Naïve Status at Time of Entry into a Large, Observational Cohort of HIV-infected Patients 
Pharmacoepidemiology and drug safety  2013;22(9):10.1002/pds.3476.
Large, observational HIV cohorts play an important role in answering questions which are difficult to study in randomized trials; however, they often lack detailed information regarding previous antiretroviral treatment (ART). Knowledge of ART treatment history is important when ascertaining the long-term impact of medications, co-morbidities, or adverse reactions on HIV outcomes.
We performed a retrospective study to validate a prediction algorithm for identifying ART-naïve patients using the Veterans Aging Cohort Study’s Virtual Cohort—an observational cohort of 40,594 HIV-infected veterans nationwide. Medical records for 3070 HIV-infected patients were reviewed to determine history of combination ART treatment. An algorithm using Virtual Cohort laboratory data was used to predict ART treatment status and compared to medical record review.
Among 3070 patients’ medical records reviewed, 1223 were eligible for analysis. Of these, 990 (81%) were ART naïve at cohort entry based on medical record review. The prediction algorithm’s sensitivity was 86%, specificity 47%, positive predictive value (PPV) 87% and negative predictive value 45%, using a viral load threshold of <400 copies/ml. Sensitivity analysis revealed that PPV would be maximized by increasing the viral load threshold, whereas sensitivity would be maximized by lowering the viral load threshold.
A prediction algorithm using available laboratory data can be used to accurately identify ART-naïve patients in large, observational HIV cohorts. Use of this algorithm will allow investigators to accurately limit analyses to ART-naïve patients when studying the contribution of ART to outcomes and adverse events.
PMCID: PMC3831617  PMID: 23836591
HIV-1; Antiretroviral Therapy, Highly Active; Cohort Studies; HIV infections/epidemiology; HIV infections/drug therapy
8.  Physiologic Frailty and Fragility Fracture in HIV-Infected Male Veterans 
Frailty, as measured by the Veterans Aging Cohort Study Index, is an important predictor of fragility fracture in the context of established fracture risk factors. Anemia and increasing age drive this association in a male veteran population.
Background. The Veterans Aging Cohort Study (VACS) Index is associated with all-cause mortality in individuals infected with human immunodeficiency virus (HIV). It is also associated with markers of inflammation and may thus reflect physiologic frailty. This analysis explores the association between physiologic frailty, as assessed by the VACS Index, and fragility fracture.
Methods. HIV-infected men from VACS were included. We identified hip, vertebral, and upper arm fractures using ICD-9-CM codes. We used Cox regression models to assess fragility fracture risk factors including the VACS Index, its components (age, hepatitis C status, FIB-4 score, estimated glomerular filtration rate, hemoglobin, HIV RNA, CD4 count), and previously identified risk factors for fragility fractures.
Results. We included 40 115 HIV-infected male Veterans. They experienced 588 first fragility fractures over 6.0 ± 3.9 years. The VACS Index score (hazard ratio [HR], 1.15; 95% confidence interval [CI], 1.11–1.19), white race (HR, 1.92; 95% CI, 1.63–2.28), body mass index (HR, 0.94; 95% CI, .92–.96), alcohol-related diagnoses (HR, 1.65; 95% CI, 1.26–2.17), cerebrovascular disease (HR, 1.95; 95% CI, 1.14–3.33), proton pump inhibitor use (HR, 1.87; 95% CI, 1.54–2.27), and protease inhibitor use (HR, 1.25; 95% CI, 1.04–1.50) were associated with fracture risk. Components of the VACS Index score most strongly associated with fracture risk were age (HR, 1.40; 95% CI, 1.27–1.54), log HIV RNA (HR, 0.91; 95% CI, .88–.94), and hemoglobin level (HR, 0.82; 95% CI, .78–.86).
Conclusions. Frailty, as measured by the VACS Index, is an important predictor of fragility fractures among HIV-infected male Veterans.
PMCID: PMC3634308  PMID: 23378285
HIV; frailty; fragility fractures; Veterans
9.  Agreement Between Electronic Medical Record-based and Self-Administered Pain Numeric Rating Scale: Clinical and Research Implications 
Medical care  2013;51(3):245-250.
Pain screening may improve the quality of care by identifying patients in need of further assessment and management. Many healthcare systems use the numeric rating scale (NRS) for pain screening, and record the score in the patients’ electronic medical record (EMR).
Determine level of agreement between EMR and patient survey NRS, and whether discrepancies vary by demographic and clinical characteristics.
We linked survey data from a sample of Veterans receiving care in eight Veterans Affairs (VA) medical facilities, to EMR data including an NRS collected on the day of the survey in order to compare responses to the NRS question from these two sources. We assessed correlation, agreement on clinical cut-points (e.g. severe), and, using the survey as the gold standard, whether patient characteristics were associated with a discrepancy on moderate-severe pain.
A total of 1,643 participants had a survey and EMR NRS score on the same day. The correlation was 0.56 (95% CI 0.52/0.59), but the mean EMR score was significantly lower than the survey score (1.72 vs. 2.79; p<0.0001). Agreement was moderate (kappa=0.35). Characteristics associated with a increased odds of a discrepancy included: diabetes (adjusted odds ratio (AOR)=1.48), post traumatic stress disorder (AOR=1.59), major depressive disorder (AOR=1.81), other race vs. white (AOR=2.29), and facility in which care was received.
The underestimation of pain using EMR data, especially clinically actionable levels of pain, has important clinical and research implications. Improving the quality of pain care may require better screening.
PMCID: PMC3572341  PMID: 23222528
Veterans; pain measurement; electronic medical records
10.  Unhealthy Alcohol and Illicit Drug Use are Associated with Decreased Quality of HIV Care 
HIV-infected patients with substance use experience suboptimal health outcomes, possibly to due to variations in care.
To assess the association between substance use and the quality of HIV care (QOC) received.
Research Design
Retrospective cohort study.
HIV-infected patients enrolled in the Veterans Aging Cohort Study.
We collected self-report substance use data and abstracted 9 HIV quality indicators (QIs) from medical records. Independent variables were unhealthy alcohol use (AUDIT-C score ≥4) and illicit drug use (self-report of stimulants, opioids, or injection drug use in past year). Main outcome was the percentage of QIs received, if eligible. We estimated associations between substance use and QOC using multivariable linear regression.
The majority of the 3,410 patients were male (97.4%) and Black (67.0%) with a mean age of 49.1 years (SD 8.8). Overall, 25.8% reported unhealthy alcohol use, 22% illicit drug use, and participants received 81.5% (SD=18.9) of QIs. The mean percentage of QIs received was lower for those with unhealthy alcohol use vs. not (59.3% vs. 70.0%, p<.001) and those using illicit drugs vs. not (57.8% vs. 70.7%, p<.001). In multivariable models, unhealthy alcohol use (adjusted β −2.74; 95% CI −4.23, −1.25) and illicit drug use (adjusted β −3.51 95% CI −4.99, −2.02) remained inversely associated with the percentage of QIs received.
Though the overall QOC for these HIV-infected Veteran patients was high, gaps persist for those with unhealthy alcohol and illicit drug use. Interventions that address substance use in HIV-infected patients may improve the QOC received.
PMCID: PMC3460799  PMID: 22820808
Alcohol; Quality of Health Care; HIV; Quality Indicators; Health Care; Opioid-Related Disorders
11.  Comorbid diabetes and the risk of progressive chronic kidney disease in HIV-infected adults: Data from the Veterans Aging Cohort Study 
Approximately 15% of HIV-infected individuals have comorbid diabetes. Studies suggest that HIV and diabetes have an additive effect on chronic kidney (CKD) progression; however, this observation may be confounded by differences in traditional CKD risk factors.
We studied a national cohort of HIV-infected and matched HIV-uninfected individuals who received care through the Veterans Healthcare Administration. Subjects were divided into four groups based on baseline HIV and diabetes status, and the rate of progression to an estimated glomerular filtration rate (eGFR) < 45ml/min/1.73m2 was compared using Cox-proportional hazards modeling to adjust for CKD risk factors.
31,072 veterans with baseline eGFR ≥ 45ml/min/1.73m2 (10,626 with HIV only, 5,088 with diabetes only, and 1,796 with both) were followed for a median of 5 years. Mean baseline eGFR was 94ml/min/1.73m2, and 7% progressed to an eGFR < 45ml/min/1.73m2. Compared to those without HIV or diabetes, the relative rate of progression was increased in individuals with diabetes only [adjusted hazard ratio (HR) 2.48; 95% confidence interval (CI) 2.19–2.80], HIV only [HR 2.80, 95% CI 2.50–3.15], and both HIV and diabetes [HR 4.47, 95% CI 3.87–5.17].
Compared to patients with only HIV or diabetes, patients with both diagnoses are at significantly increased risk of progressive CKD even after adjusting for traditional CKD risk factors. Future studies should evaluate the relative contribution of complex comorbidities and accompanying polypharmacy to the risk of CKD in HIV-infected individuals, and prospectively investigate the use of cART, glycemic control, and adjunctive therapy to delay CKD progression.
PMCID: PMC3392432  PMID: 22592587
non-AIDS complications; HIV; chronic kidney disease; diabetes; risk factors
12.  HIV Status, Burden of Comorbid Disease, and Biomarkers of Inflammation, Altered Coagulation, and Monocyte Activation 
We investigated the association between human immunodeficiency virus (HIV) and prevalence of elevated biomarkers of inflammation, altered coagulation, and monocyte activation in a cohort of HIV-infected and uninfected veterans who had a comparable burden of comorbid conditions.
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.
PMCID: PMC3493182  PMID: 22534147
13.  Sex Disparities in Overall Burden of Disease Among HIV-Infected Individuals in the Veterans Affairs Healthcare System 
Journal of General Internal Medicine  2013;28(Suppl 2):577-582.
Whether sex disparities exist in overall burden of disease among human immunodeficiency virus (HIV)-infected individuals in the Veterans Affairs healthcare system (VA) is unknown.
To determine whether sex differences exist in overall burden of disease after 1 year of combined antiretroviral therapy (ART) among HIV-infected individuals in VA.
Retrospective cohort study.
Among patients in the Veterans Aging Cohort Study Virtual Cohort (VACS-VC), all ART-naïve HIV-infected Veterans who received VA-based HIV care between 1996 and 2009.
Overall burden of disease was measured using the VACS Index, an index that incorporates HIV (e.g. CD4 cell count) and non-HIV biomarkers (e.g. hemoglobin) and is highly predictive of all-cause mortality. Possible scores range from 0 to 164, although scores typically range from 0 to 50 for 80 % of patients in VACS-VC. A higher score indicates greater burden of disease (each additional five points indicates approximately 20 % increased 5-year mortality risk). ART adherence was measured using pharmacy data.
Complete data were available for 227 women and 8,073 men. At ART initiation, compared with men, women were younger and more likely to be Black, less likely to have liver dysfunction, but more likely to have lower hemoglobin levels. Median VACS Index scores changed from ART initiation to 1 year after ART initiation: women’s scores went from 41 to 28 for women (13 point improvement) and men’s from 42 to 27 for men (15 point improvement). In multivariable regression, women had 3.6 point worse scores than men after 1 year on ART (p = 0.002); this difference decreased to 3.2 points after adjusting for adherence (p = 0.004).
In VA, compared to men, women experienced less improvement in overall burden of disease after 1 year of HIV treatment. Further study is needed to elucidate the modifiable factors that may explain this disparity.
PMCID: PMC3695278  PMID: 23807068
women; Veterans; HIV; health care disparities; burden of illness
14.  Risk of Heart Failure With Human Immunodeficiency Virus in the Absence of Prior Diagnosis of Coronary Heart Disease 
Archives of internal medicine  2011;171(8):737-743.
Whether human immunodeficiency virus (HIV) infection is a risk factor for heart failure (HF) is not clear. The presence of coronary heart disease and alcohol consumption in this population may confound this association.
To determine whether HIV infection is a risk factor for incident HF, we conducted a population-based, retrospective cohort study of HIV-infected and HIV-uninfected veterans enrolled in the Veterans Aging Cohort Study Virtual Cohort (VACS-VC) and the 1999 Large Health Study of Veteran Enrollees (LHS) from January 1, 2000, to July 31, 2007.
There were 8486 participants (28.2% HIV-infected) enrolled in the VACS-VC who also participated in the 1999 LHS. During the median 7.3 years of follow-up, 286 incident HF events occurred. Age- and race/ethnicity–adjusted HF rates among HIV-infected and HIV-uninfected veterans were 7.12 (95% confidence interval [CI],6.90-7.34) and 4.82 (95% CI, 4.72-4.91) per 1000 person-years, respectively. Compared with HIV-uninfected veterans, those who were HIV infected had an increased risk ofHF (adjusted hazard ratio [HR], 1.81; 95% CI, 1.39-2.36). This association persisted among veterans who did not have a coronary heart disease event or a diagnosis related to alcohol abuse or dependence before the incident HF event (adjusted HR, 1.96; 95% CI, 1.29-2.98). Compared with HIV-uninfected veterans, those who were HIV infected with a baseline Human immunodeficiency virus 1 (HIV-1) RNA level of 500 or more copies/mL had a higher risk of HF (adjusted HR, 2.28; 95% CI, 1.57-3.32), while those with baseline and a recent HIV-1 RNA level less than 500 copies/mL did not (adjusted HR, 1.10; 95% CI, 0.64-1.89; P< .001 for comparison between high and low HIV-1 RNA groups).
Our data suggest that HIV infection is a risk factor for HF. Ongoing viral replication is associated with a higher risk of developing HF.
PMCID: PMC3687533  PMID: 21518940
15.  Do Patterns of Comorbidity Vary by HIV Status, Age, and HIV Severity? 
Patterns of comorbidity among persons with human immunodeficiency virus (HIV) are not well described. We compared comorbidity among veterans with and without HIV infection. The sample consisted of 33,420 HIV-infected veterans and 66,840 HIV-uninfected veterans. We identified and clustered 11 comorbid conditions using validated International Classification of Diseases, 9th Revision, Clinical Modification codes. We defined multimorbidity as the presence of conditions in all clusters. Models restricted to HIV-infected veterans were adjusted for CD4 cell count and viral load. Comorbidity was common (prevalence, 60%–63%), and prevalence varied by HIV status. Differences remained when the veterans were stratified by age. In multivariable analyses, older HIV-infected veterans were more likely to have substance use disorder and multimorbidity. Renal, vascular, and pulmonary diseases were associated with CD4 cell count <200 cells/mm3; hypertension was associated with CD4 cell count >200 cells/mm3. Comorbidity is the rule, and multimorbidity is common among veterans with HIV infection. Patterns of comorbidity differ substantially by HIV status, age, and HIV severity. Primary care guidelines require adaptation for persons with HIV infection.
PMCID: PMC3687553  PMID: 18190322
16.  Does an Index Composed of Clinical Data Reflect Effects of Inflammation, Coagulation, and Monocyte Activation on Mortality Among Those Aging With HIV? 
The Veterans Aging Cohort Study (VACS) Index, based on age and 8 routine clinical tests, is strongly correlated with 3 biomarkers of inflammation: interleukin 6 (IL-6), D-dimer, and soluble CD14 (sCD14). After adjustment for the VACS Index, D-dimer and sCD14, but not IL-6, remain independently associated with mortality.
Background. When added to age, CD4 count and human immunodeficiency virus type 1 (HIV-1) RNA alone (Restricted Index), hemoglobin, FIB-4 Index, hepatitis C virus (HCV), and estimated glomerular filtration rate improve prediction of mortality. Weighted and combined, these 7 routine clinical variables constitute the Veterans Aging Cohort Study (VACS) Index. Because nonroutine biomarkers of inflammation (interleukin 6 [IL-6]), coagulation (D-dimer), and monocyte activation (sCD14) also predict mortality, we test the association of these indices and biomarkers with each other and with mortality.
Methods. Samples from 1302 HIV-infected veterans on antiretroviral therapy were analyzed. Indices were calculated closest to date of collection. We calculated Spearman correlations stratified by HIV-1 RNA and HCV status and measured association with mortality using C statistics and net reclassification improvement (NRI).
Results. Of 1302 subjects, 915 had HIV-1 RNA <500 copies/mL and 154 died. The VACS Index was more correlated with IL-6, D-dimer, and sCD14 than the Restricted Index (P < .001). It was also more predictive of mortality (C statistic, 0.76; 95% confidence interval [CI], .72–.80) than any biomarker (C statistic, 0.66–0.70) or the Restricted Index (C statistic, 0.71; 95% CI, .67–.75). Compared to the Restricted Index alone, NRI resulted from incremental addition of VACS Index components (10%), D-dimer (7%), and sCD14 (4%), but not from IL-6 (0%).
Conclusions. Among HIV-infected individuals, independent of CD4, HIV-1 RNA, and age, hemoglobin and markers of liver and renal injury are associated with inflammation. Addition of D-dimer and sCD14, but not IL-6, improves the predictive accuracy of the VACS Index for mortality.
PMCID: PMC3297653  PMID: 22337823
17.  HIV as an Independent Risk Factor for Incident Lung Cancer 
AIDS (London, England)  2012;26(8):1017-1025.
PMCID: PMC3580210  PMID: 22382152
Human Immunodeficiency Virus (HIV); lung cancer; incidence; smoking; immunosuppression; non-AIDS defining malignancy
18.  Validating Smoking Data From the Veteran’s Affairs Health Factors Dataset, an Electronic Data Source 
Nicotine & Tobacco Research  2011;13(12):1233-1239.
We assessed smoking data from the Veterans Health Administration (VHA) electronic medical record (EMR) Health Factors dataset.
To assess the validity of the EMR Health Factors smoking data, we first created an algorithm to convert text entries into a 3-category smoking variable (never, former, and current). We compared this EMR smoking variable to 2 different sources of patient self-reported smoking survey data: (a) 6,816 HIV-infected and -uninfected participants in the 8-site Veterans Aging Cohort Study (VACS-8) and (b) a subset of 13,689 participants from the national VACS Virtual Cohort (VACS-VC), who also completed the 1999 Large Health Study (LHS) survey. Sensitivity, specificity, and kappa statistics were used to evaluate agreement of EMR Health Factors smoking data with self-report smoking data.
For the EMR Health Factors and VACS-8 comparison of current, former, and never smoking categories, the kappa statistic was .66. For EMR Health Factors and VACS-VC/LHS comparison of smoking, the kappa statistic was .61.
Based on kappa statistics, agreement between the EMR Health Factors and survey sources is substantial. Identification of current smokers nationally within the VHA can be used in future studies to track smoking status over time, to evaluate smoking interventions, and to adjust for smoking status in research. Our methodology may provide insights for other organizations seeking to use EMR data for accurate determination of smoking status.
PMCID: PMC3223583  PMID: 21911825
19.  FIB-4 index is associated with hepatocellular carcinoma risk in HIV-infected patients 
Chronic inflammation caused by hepatitis B virus infection, hepatitis C virus infection, and/or heavy alcohol use can lead to fibrosis, cirrhosis, and eventually hepatocellular carcinoma (HCC). FIB-4 is an index score calculated from platelet count, alanine transaminase, aspartate transaminase, and age that predicts fibrosis and cirrhosis. We hypothesized that high FIB-4 would be associated with development of HCC in HIV-infected persons, who are at high risk due to high prevalence of viral hepatitis and alcohol consumption, and possibly due to HIV infection itself.
Using proportional hazards models, we tested this hypothesis among 22,980 HIV-infected men from the Veterans Aging Cohort Study. We identified incident HCC cases from the VA Central Cancer Registry.
During follow-up, there were 112 incident HCC diagnoses. The age-and race/ethnic group-adjusted HR was 4.2 (95% CI: 2.4, 7.4)for intermediate FIB-4 and 13.0 (95% CI: 7.2, 23.4) for high FIB-4, compared to low FIB-4. After further adjustment for enrollment year, CD4 count, HIV-1 RNA level, antiretroviral therapy use, hepatitis B and C virus infection, alcohol abuse/dependency, and diabetes, FIB-4 remained a strong, significant, independent risk factor for HCC. The multivariate-adjusted HR was 3.6 (95% CI: 2.1, 6.4) for intermediate FIB-4 and 9.6 (95% CI: 5.2, 17.4) for high FIB-4.
Calculated from routine, non-invasive laboratory tests, FIB-4 is a strong, independent HCC risk factor in HIV-infected patients.
FIB-4 might prove valuable as an easily measured index to identify those at highest risk for HCC, even prior to development of clinical cirrhosis.
PMCID: PMC3237927  PMID: 22028407
hepatocellular carcinoma; FIB-4; HIV; liver neoplasms; hepatic fibrosis
20.  Adherence, virological and immunological outcomes for HIV-infected veterans starting combination antiretroviral therapies 
AIDS (London, England)  2007;21(12):1579-1589.
We aimed to determine adherence, virological, and immunological outcomes one year after starting a first combination antiretroviral therapy (ART) regimen.
Observational; synthesis of administrative, laboratory, and pharmacy data. Antiretroviral regimens were divided into efavirenz, nevirapine, boosted protease inhibitor (PI), and single PI categories. Propensity scores were used to control for confounding by treatment assignment. Adherence was estimated from pharmacy refill records.
Veterans Affairs Healthcare System, all sites.
HIV-infected individuals starting combination ART with a low likelihood of previous antiretroviral exposure.
The proportion of antiretroviral prescriptions filled as prescribed, a change in log HIV-RNA, the proportion with log HIV-RNA viral suppression, a change in CD4 cell count.
A total of 6394 individuals unlikely to have previous antiretroviral exposure started combination ART between 1996 and 2004, and were eligible for analysis. Adherence overall was low (63% of prescriptions filled as prescribed), and adherence with efavirenz (67%) and nevirapine (65%) regimens was significantly greater than adherence with boosted PI (59%) or single PI (61%) regimens (P < 0.001). Efavirenz regimens were more likely to suppress HIV-RNA at one year (74%) compared with nevirapine (62%), boosted PI (63%), or single PI (53%) regimens (all P < 0.001), and this superiority was maintained when analyses were adjusted for baseline clinical characteristics and propensity for treatment assignment. Efavirenz also yielded more favorable immunological outcomes.
HIV-infected individuals initiating their first combination ART using an efavirenz-based regimen had improved virological and immunological outcomes and greater adherence levels.
PMCID: PMC3460378  PMID: 17630553
Adherence; resistance; ART; Veterans Affairs Healthcare System
21.  Food Insecurity is Associated with Poor Virologic Response among HIV-Infected Patients Receiving Antiretroviral Medications 
Journal of General Internal Medicine  2011;26(9):1012-1018.
Food insecurity negatively impacts HIV disease outcomes in international settings. No large scale U.S. studies have investigated the association between food insecurity and severity of HIV disease or the mechanism of this possible association. The objective of this study was to examine the impact of food insecurity on HIV disease outcomes in a large cohort of HIV-infected patients receiving antiretroviral medications.
This is a cross-sectional study.
Participants were HIV-infected patients enrolled in the Veterans Aging Cohort Study between 2002–2008 who were receiving antiretroviral medications.
Participants reporting “concern about having enough food for you or your family in the past 30 days” were defined as food insecure. Using multivariable logistic regression, we explored the association between food insecurity and both low CD4 counts (<200 cells/μL) and unsuppressed HIV-1 RNA (>500 copies/mL). We then performed mediation analysis to examine whether antiretroviral adherence or body mass index mediates the observed associations.
Among 2353 HIV-infected participants receiving antiretroviral medications, 24% reported food insecurity. In adjusted analyses, food insecure participants were more likely to have an unsuppressed HIV-1 RNA (AOR 1.37, 95% CI 1.09, 1.73) compared to food secure participants. Mediation analysis revealed that neither antiretroviral medication adherence nor body mass index contributes to the association between food insecurity and unsuppressed HIV-1 RNA. Food insecurity was not independently associated with low CD4 counts.
Among HIV-infected participants receiving antiretroviral medications, food insecurity is associated with unsuppressed viral load and may render treatment less effective. Longitudinal studies are needed to test the potential causal association between food insecurity, lack of virologic suppression, and additional HIV outcomes.
PMCID: PMC3157515  PMID: 21573882
food insecurity; HIV; patients; antiretrovirals
22.  Validity of Diagnostic Codes and Liver-Related Laboratory Abnormalities to Identify Hepatic Decompensation Events in the Veterans Aging Cohort Study 
The absence of validated methods to identify hepatic decompensation in cohort studies has prevented a full understanding of the natural history of chronic liver diseases and impact of medications on this outcome. We determined the ability of diagnostic codes and liver-related laboratory abnormalities to identify hepatic decompensation events within the Veterans Aging Cohort Study (VACS).
Medical records of patients with hepatic decompensation codes and/or laboratory abnormalities of liver dysfunction (total bilirubin ≥5.0 gm/dL, albumin ≤2.0 gm/dL, international normalized ratio ≥1.7) recorded one year before through six months after VACS entry were reviewed to identify decompensation events (i.e., ascites, spontaneous bacterial peritonitis, variceal hemorrhage, hepatic encephalopathy, hepatocellular carcinoma) at VACS enrollment. Positive predictive values (PPVs) of diagnostic codes, laboratory abnormalities, and their combinations for confirmed outcomes were determined.
Among 137 patients with a hepatic decompensation code and 197 with a laboratory abnormality, the diagnosis was confirmed in 57 (PPV, 42%; 95% CI, 33% – 50%) and 56 (PPV, 28%; 95% CI, 22% – 35%), respectively. The combination of any code plus laboratory abnormality increased PPV (64%; 95% CI, 47% - 79%). One inpatient or ≥2 outpatient diagnostic codes for ascites, spontaneous bacterial peritonitis, or variceal hemorrhage had high PPV (91%; 95% CI, 77% – 98%) for confirmed hepatic decompensation events.
An algorithm of 1 inpatient or ≥2 outpatient codes for ascites, peritonitis, or variceal hemorrhage has sufficiently high PPV for hepatic decompensation to enable its use for epidemiologic research in VACS. This algorithm may be applicable to other cohorts.
PMCID: PMC3131229  PMID: 21626605
hepatic decompensation; end-stage liver disease; epidemiologic methods; outcomes; validation studies
23.  The Risk of Incident Coronary Heart Disease Among Veterans with and without HIV and Hepatitis C 
Whether hepatitis C (HCV) confers additional coronary heart disease (CHD) risk among Human Immunodeficiency Virus (HIV) infected individuals is unclear. Without appropriate adjustment for antiretroviral therapy, CD4 count, and HIV-1 RNA, and substantially different mortality rates among those with and without HIV and HCV infection, the association between HIV, HCV, and CHD may be obscured.
Methods and Results
We analyzed data on 8579 participants (28% HIV+, 9% HIV+HCV+) from the Veterans Aging Cohort Study Virtual Cohort who participated in the 1999 Large Health Study of Veteran Enrollees. We analyzed data collected on HIV and HCV status, risk factors for and the incidence of CHD, and mortality from 1/2000–7/2007. We compared models to assess CHD risk when death was treated as a censoring event and as a competing risk. During the median 7.3 years of follow-up, there were 194 CHD events and 1186 deaths. Compared with HIV−HCV− Veterans, HIV+ HCV+ Veterans had a significantly higher risk of CHD regardless of whether death was adjusted for as a censoring event (adjusted hazard ratio (HR)=2.03, 95% CI=1.28–3.21) or a competing risk (adjusted HR=2.45, 95% CI=1.83–3.27 respectively). Compared with HIV+HCV− Veterans, HIV+ HCV+ Veterans also had a significantly higher adjusted risk of CHD regardless of whether death was treated as a censored event (adjusted HR=1.93, 95% CI=1.02–3.62) or a competing risk (adjusted HR =1.46, 95% CI=1.03–2.07).
HIV+HCV+ Veterans have an increased risk of CHD compared to HIV+HCV−, and HIV−HCV− Veterans.
PMCID: PMC3159506  PMID: 21712519
viruses; coronary disease; mortality; multi morbidity
24.  HIV Infection and Risk for Incident Pulmonary Diseases in the Combination Antiretroviral Therapy Era 
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.
PMCID: PMC3266024  PMID: 20851926
HIV; respiratory tract diseases; lung diseases, obstructive; pneumonia; pneumonia, bacterial

Results 1-25 (45)