Incidence, etiology, and severity of acute gastroenteritis among prospectively enrolled patients in 4 Veterans Affairs hospitals and outpatient centers, 2016-18

BACKGROUND

Acute gastroenteritis (AGE) burden, etiology, and severity in adults is not well-characterized. We implemented a multisite AGE surveillance platform in 4 Veterans Affairs Medical Centers (Atlanta, Bronx, Houston and Los Angeles), collectively serving >320,000 patients annually.

METHODS

From July 1, 2016-June 30, 2018, we actively identified AGE inpatient cases and non-AGE inpatient controls through prospective screening of admitted patients and passively identified outpatient cases through stool samples submitted for clinical diagnostics. We abstracted medical charts and tested stool samples for 22 pathogens via multiplex gastrointestinal PCR panel followed by genotyping of norovirus- and rotavirus-positive samples. We determined pathogen-specific prevalence, incidence, and modified Vesikari severity scores.

RESULTS

We enrolled 724 inpatient cases, 394 controls, and 506 outpatient cases. Clostridioides difficile and norovirus were most frequently detected among inpatients (cases vs controls: C. difficile, 18.8% vs 8.4%; norovirus, 5.1% vs 1.5%; p<0.01 for both) and outpatients (norovirus: 10.7%; C. difficile: 10.5%). Incidence per 100,000 population was highest among outpatients (AGE: 2715; C. difficile: 285; norovirus: 291) and inpatients ≥65 years old (AGE: 459; C. difficile: 91; norovirus: 26). Clinical severity scores were highest for inpatient norovirus, rotavirus, and Shigella/EIEC cases. Overall, 12% of AGE inpatient cases had ICU stays and 2% died; 3 deaths were associated with C. difficile and 1 with norovirus. C. difficile and norovirus were detected year-round with a fall/winter predominance.

CONCLUSIONS

C. difficile and norovirus were leading AGE pathogens in outpatient and hospitalized US Veterans, resulting in severe disease. Clinicians should remain vigilant for bacterial and viral causes of AGE year-round.

Validation of Acute Gastroenteritis-related International Classification of Diseases, Clinical Modification Codes in Pediatric and Adult US Populations

International Classification of Diseases diagnostic codes are used to estimate acute gastroenteritis (AGE) disease burden. We validated AGE-related codes in pediatric and adult populations using 2 multiregional active surveillance platforms. The sensitivity of AGE codes was similar (54% and 58%) in both populations and increased with addition of vomiting-specific codes.

SUN-518 Graves’ Disease Newly Diagnosed in the Setting of Hypokalemic Periodic Paralysis in an HIV+ Patient

Relevance: A rare yet distinct cause of sudden onset paralysis is severe hypokalemia associated with thyrotoxicosis. This is thought to be associated with mutations in genes encoding cellular potassium channels. We report a case of acute onset paralysis with profound hypokalemia and a new diagnosis of Graves’ thyrotoxicosis in a previously asymptomatic African American, HIV+ man on highly active antiretroviral therapy (HAART) for over 8 years.

Clinical case: A 49-year-old man with hypertension and HIV presented with acute paralysis of his bilateral upper and lower extremities. His initial potassium was 1.8 mEq/L (3.5-5.0). Prior to sudden onset loss of motor strength, he denied any preceding palpitations, tremor, anxiety, diaphoresis, hyper-defecation, weight loss, heat or cold intolerance, neck pain, increase in neck girth or difficulty swallowing, proptosis or other ocular symptoms. He has no family history of thyroid disease. He had an enlarged palpable thyroid without nodules and no audible bruit. There was no periorbital edema or proptosis, and no signs of dermopathy. A thyroid ultrasound showed a hyperemic and diffusely enlarged thyroid gland without nodules. Labs included a TSH of 0.007 mCU/mL (0.43-3.8), Free T4 2.1 ng/dL (0.71-1.85), Total T3 229.6 ng/dL (58-194), and thyrotropin receptor antibody 2.6 IU/L (0-1.75). The CD4+ count was 146 in 2010 with a slow gradual rise to 673 in 2019, and HIV viral load was undetectable. There were no offending medications or supplements identified. With aggressive potassium repletion, the serum potassium improved to 4.6 mEq/L and he regained normal strength within several hours. He was started on Methimazole 10mg daily and propranolol 10mg TID. At one month, the thyroid function tests normalized. Methimazole 10mg daily was continued and propranolol was tapered off. He remains euthyroid. Genetic testing is pending.

Conclusions: Graves’ disease is the most common thyroid disease triggered by immune reconstitution in HIV + individuals on HAART. The incidence of thyroid disease in HIV patients on HAART is higher in women and Africans with a 1.5-2 fold increase compared with the general population [Muller et. al, Eur Thyroid J 2019;8:173-185]. Despite a higher incidence of hyperthyroidism in women, over 95% of cases of hypokalemic periodic paralysis have been reported in men, with a 10-fold higher incidence among Asians compared to Westerners. There has been one prior case report of Thyrotoxic Periodic Paralysis in an HIV + patient and this was in a Polynesian male (Brown JD et al. Hawaii Med J 2007). To our knowledge, this is the first case report of an African American HIV+ patient with this disorder. An association with mutations in the Kir2.6 gene (encodes a potassium channel, is expressed in skeletal muscle, and is transcriptionally regulated by thyroid hormone) has been proposed [Ryan et. al, Cell 2010 January 8; 140(1):88-98].

Crohn's disease: failure of a proprietary fluorescent in situ hybridization assay to detect M. avium subspecies paratuberculosis in archived frozen intestine from patients with Crohn's disease

Objectives

Although controversial, there is increasing concern that Crohn’s disease may be a zoonotic infectious disease consequent to a mycobacterial infection. The most plausible candidate is M. avium subspecies paratuberculosis (MAP) that is unequivocally responsible for Johne’s disease in ruminants. The purpose of this study was to evaluate a proprietary (Affymetrix™ RNA view^®) fluorescent in situ hybridization (FISH) assay for MAP RNA. Non-identifiable intestine from patients with documented Crohn’s disease was assayed according to the manufacturer’s instructions and with suggested modifications. Probes were custom designed for MAP and human β-actin (as the eukaryotic housekeeping gene) from published genomes.

Results

Repetitively, false positive signal was observed in our “No-Probe” negative control. Attempts were made to correct this according to the manufacturer’s suggestions (by modifying wash solutions, using recommended hydrochloric acid titration and different fluorescent filters). None prevented false positive signal in the “No-Probe” control. It is concluded that when performed according to manufactures instruction and with multiple variations on the manufactures recommended suggestions to correct for false positive signal, that the Affymetrix™ RNA view^® cannot be used to detect MAP in pre-frozen resected intestine of humans with Crohn’s disease.

A multicenter randomized placebo controlled trial of rifampin to reduce pedal amputations for osteomyelitis in veterans with diabetes (VA INTREPID)

Background

The prevalence of diabetes mellitus continues to inexorably rise in the United States and throughout the world. Lower limb amputations are a devastating comorbid complication of diabetes mellitus. Osteomyelitis increases the risk of amputation fourfold and commonly presages death.

Antimicrobial therapy for diabetic foot osteomyelitis (DFO) varies greatly, indicating that high quality data are needed to inform clinical decision making. Several small trials have indicated that the addition of rifampin to backbone antimicrobial regimens for osteomyelitis outside the setting of the diabetic foot results in 28 to 42% higher cure rates.

Methods/design

This is a prospective, randomized, double-blind investigation of the addition of 6 weeks of rifampin, 600 mg daily, vs. matched placebo (riboflavin) to standard-of-care, backbone antimicrobial therapy for DFO. The study population are patients enrolled in Veteran Health Administration (VHA), ages ≥18 and ≤ 89 years with diabetes mellitus and definite or probable osteomyelitis of the foot for whom an extended course of oral or intravenous antibiotics is planned. The primary endpoint is amputation-free survival. The primary hypothesis is that using rifampin as adjunctive therapy will lower the hazard rate compared with the group that does not use rifampin as adjunctive therapy. The primary hypothesis will be tested by means of a two-sided log-rank test with a 5% significance level. The test has 90% power to detect a hazard ratio of 0.67 or lower with a total of 880 study participants followed on average for 1.8 years.

Discussion

VA INTREPID will test if a rifampin-adjunctive antibiotic regimen increases amputation-free survival in patients seeking care in the VHA with DFO. A positive finding and its adoption by clinicians would reduce lower extremity amputations and their associated physical and emotional impact and reduce mortality for Veterans and for the general population with diabetic foot osteomyelitis. Given that rifampin-adjunctive regimens are currently employed for therapy for the majority of DFO cases in Europe, and only in a small minority of cases in the United States, the trial results will impact therapeutic decisions, even if the null hypothesis is not rejected.

Trial registration

Registered January 6, 2017 at ClinicalTrials.gov, NCT03012529.

Adjunctive Rifampin Therapy For Diabetic Foot Osteomyelitis in the Veterans Health Administration

IMPORTANCE

Among patients diagnosed with diabetes, the lifetime incidence of foot ulcers is 15%. Infection is a common complication of foot ulcers, and 20% to 60% of infections result in diabetic foot osteomyelitis (DFO). Current treatment guidelines do not endorse any specific antibiotic agent for DFO, but small clinical trials suggest the addition of rifampin to antimicrobial regimens results in improved cure rates for osteomyelitis.

OBJECTIVE

To compare the clinical outcomes of patients treated for DFO in the Veterans Health Administration (VHA) with and without adjunctive rifampin.

DESIGN, SETTING, AND PARTICIPANTS

This observational cohort study used VHA databases to identify index DFO cases from January 1, 2009, through December 31, 2013, and analyzed patients alive and without high-level amputation at 90 days after diagnosis in whom antibiotic therapy was initiated within 6 weeks of diagnosis. Patients with death or major amputation within 90 days of diagnosis, who were not treated with systemic antibiotics dispensed by the VHA within 6 weeks of diagnosis, or who were treated at facilities where rifampin was not dispensed for DFO were excluded. The retrospective cohort to inform the planning of a multisite randomized clinical trial was first investigated in spring 2015; retrospective analysis was performed from February 2017 through September 2019.

EXPOSURES

Patients initiating rifampin therapy within 6 weeks of the DFO diagnosis and receiving the drug for at least 14 days within 90 days of diagnosis were considered treated with rifampin. Patients not administered rifampin within 90 days of diagnosis served as the comparator group.

MAIN OUTCOMES AND MEASURES

A combined end point of mortality or amputation within 2 years of diagnosis was analyzed. Differences in times to event were evaluated using log-rank tests. Differences in event rates were compared using χ2 tests and multivariable logistic regression.

RESULTS

The analysis population included 130 patients treated with rifampin and 6044 treated without rifampin (total of 6174; 6085 men [98.6%]; mean [SD] age, 64.9 [9.7] years). Lower event rates were observed among the rifampin group (35 of 130 [26.9%] vs 2250 of 6044 [37.2%]; P = .02). Patients treated with rifampin were younger (mean [SD] age, 62.2 [9.4] vs 64.9 [9.6] years), had fewer comorbidities (mean [SD] Charlson comorbidity index score, 3.5 [1.8] vs 4.0 [2.2]), had more infectious disease specialty consultations (63 of 130 [48.5%] vs 1960 of 6044 [32.4%]), and more often had Staphylococcus aureus identified in cultures (55 of 130 [42.3%] vs 1755 of 6044 [29.0%]) than patients not treated with rifampin. A logistic regression estimating the odds of events and controlling for these and other covariates yielded a significant association of rifampin (odds ratio, 0.65; 95% CI, 0.43-0.96; P = .04).

CONCLUSIONS AND RELEVANCE

In this cohort study, patients administered rifampin experienced lower rates of death and amputation than patients not treated with rifampin, which remained significant after adjustment for confounders. These results coupled with existing evidence from small clinical trials suggest the addition of rifampin to current treatment regimens may be a useful antimicrobial option in the treatment of DFO.

2322. Etiology, Severity of Illness, and Risk Factors for Patients Hospitalized with Acute Gastroenteritis from Multi-Site Veteran’s Affairs (VA) Surveillance, 2016–2018: Results from SUPERNOVA

Background

The severity of acute gastroenteritis (AGE) in adult populations and the relative contribution of specific pathogens is not well characterized. In 2016, we implemented a multisite AGE surveillance platform in 4 VA hospitals (Atlanta, Bronx, Houston and Los Angeles), collectively serving > 320,000 patients annually.

Methods

Inpatient AGE cases and age- and time-matched non-AGE controls were identified through prospective screening of admissions using standardized case definitions. Stool samples were tested for 22 pathogens using the FilmArray® Gastrointestinal Panel. Medical conditions were analyzed as risk factors for AGE by multivariate logistic regression.

Results

From July 2016 to June 2018, 731 cases and 399 controls were enrolled. Risk factors for AGE cases included HIV-positive status (adjusted odds ratio [aOR] 4.6; 95% confidence interval [CI] 1.6–12.9; P < 0.01), severe kidney disease (aOR 4.5; 95% CI 2.0–9.8; P < 0.01), and immunosuppressive therapy (aOR 4.0; 95% CI 1.2–13.3]; P = 0.02). Clostridioides difficile and norovirus were the most commonly detected pathogens in cases (18% and 5%, respectively); detection of these pathogens in cases was significantly higher than detection in controls (8% and 2%, respectively; P < 0.01 for both). The median duration of hospital stay was longer for C. difficile compared with norovirus cases (5 vs. 3 days; P < 0.01), and cases with both pathogens had intensive care unit (ICU) stays (C. difficile: 18%; norovirus: 8%; P = 0.2). Fourteen deaths occurred among AGE cases; 2 were associated with C. difficile and 1 with norovirus; the remainder did not have a clear etiology or pathogen detected. C. difficile and norovirus were detected year-round with a fall and winter predominance; C. difficile prevalence was highest in October, while norovirus prevalence was six times higher in December than in summer months.

Conclusion

This surveillance platform captured cases of severe AGE, including ICU stays and deaths, among hospitalized US Veterans. C. difficile and norovirus were leading pathogens in AGE cases. These findings can help guide appropriate clinical management of AGE patients and inform public health efforts to quantify and address the associated burden of disease through targeted interventions.

Disclosures

All authors: No reported disclosures.

Association Between HIV Infection and the Risk of Heart Failure With Reduced Ejection Fraction and Preserved Ejection Fraction in the Antiretroviral Therapy Era: Results From the Veterans Aging Cohort Study

Importance

With improved survival, heart failure (HF) has become a major complication for individuals with human immunodeficiency virus (HIV) infection. It is unclear if this risk extends to different types of HF in the antiretroviral therapy (ART) era. Determining whether HIV infection is associated with HF with reduced ejection fraction (HFrEF), HF with preserved ejection fraction (HFpEF), or both is critical because HF types differ with respect to underlying mechanism, treatment, and prognosis.

Objectives

To investigate whether HIV infection increases the risk of future HFrEF and HFpEF and to assess if this risk varies by sociodemographic and HIV-specific factors.

Design, Setting, and Participants

This study evaluated 98 015 participants without baseline cardiovascular disease from the Veterans Aging Cohort Study, an observational cohort of HIV-infected veterans and uninfected veterans matched by age, sex, race/ethnicity, and clinical site, enrolled on or after April 1, 2003, and followed up through September 30, 2012. The dates of the analysis were October 2015 to November 2016.

Exposure

Human immunodeficiency virus infection.

Main Outcomes and Measures

Outcomes included HFpEF (EF≥50%), borderline HFpEF (EF 40%-49%), HFrEF (EF<40%), and HF of unknown type (EF missing).

Results

Among 98 015 participants, the mean (SD) age at enrollment in the study was 48.3 (9.8) years, 97.0% were male, and 32.2% had HIV infection. During a median follow-up of 7.1 years, there were 2636 total HF events (34.6% were HFpEF, 15.5% were borderline HFpEF, 37.1% were HFrEF, and 12.8% were HF of unknown type). Compared with uninfected veterans, HIV-infected veterans had an increased risk of HFpEF (hazard ratio [HR], 1.21; 95% CI, 1.03-1.41), borderline HFpEF (HR, 1.37; 95% CI, 1.09-1.72), and HFrEF (HR, 1.61; 95% CI, 1.40-1.86). The risk of HFrEF was pronounced in veterans younger than 40 years at baseline (HR, 3.59; 95% CI, 1.95-6.58). Among HIV-infected veterans, time-updated HIV-1 RNA viral load of at least 500 copies/mL compared with less than 500 copies/mL was associated with an increased risk of HFrEF, and time-updated CD4 cell count less than 200 cells/mm3 compared with at least 500 cells/mm3 was associated with an increased risk of HFrEF and HFpEF.

Conclusions and Relevance

Individuals who are infected with HIV have an increased risk of HFpEF, borderline HFpEF, and HFrEF compared with uninfected individuals. The increased risk of HFrEF can manifest decades earlier than would be expected in a typical uninfected population. Future research should focus on prevention, risk stratification, and identification of the mechanisms for HFrEF and HFpEF in the HIV-infected population.

Efficacy of Extended-Release Naltrexone on HIV-Related and Drinking Outcomes Among HIV-Positive Patients: A Randomized-Controlled Trial

We sought to test the efficacy of extended-release naltrexone (XR-NTX) on HIV-related and drinking outcomes. From April 2011-February 2015, we conducted a 4-site randomized double-blind placebo controlled clinical trial involving 51 HIV-positive patients with heavy drinking and < 95% antiretroviral (ART) adherence. All participants received counseling. The primary outcome was proportion with ≥ 95% ART adherence. Secondary outcomes included HIV biomarkers, VACS Index score, and past 30-day heavy drinking days. Based on receipt of ≥ 5 injections, 23 participants were retained at 24 weeks. We did not detect an effect of XR-NTX on ART adherence (p = 0.38); undetectable HIV viral load (p = 0.26); CD4 cell count (p = 0.75) or VACS Index score (p = 0.70). XR-NTX was associated with fewer heavy drinking days (p = 0.03). While XR-NTX decreases heavy drinking days, we did not detect improvements in ART adherence or HIV outcomes. Strategies to improve retention in alcohol treatment and HIV-related outcomes among heavy drinking HIV-positive patients are needed.

Herpes Zoster and Herpes Zoster Vaccine Rates Among Adults Living With and Without HIV in the Veterans Aging Cohort Study

BACKGROUND

Despite historically high rates of herpes zoster among people living with HIV (PLWH), comparative studies of herpes zoster by HIV serostatus are lacking since the advent of combination antiretroviral therapy and availability of zoster vaccine.

METHODS

Annual rates (2002-2015) of first-episode herpes zoster and zoster vaccination were calculated for PLWH and uninfected adults in the Veterans Aging Cohort Study and stratified by HIV serostatus and age. Herpes zoster was captured using ICD9 codes and vaccine receipt with procedural codes and pharmacy data.

RESULTS

Of 45,177 PLWH and 103,040 uninfected veterans, rates of herpes zoster decreased among PLWH (17.6-8.1/1000) over the study period but remained higher than uninfected adults (4.1/1000) at the end of study period. Rates were higher in PLWH with lower CD4 (<200 vs >500 cells/µL: 18.0 vs 6.8/1000) and unsuppressed vs suppressed HIV-1 RNA (21.8 vs 7.1/1000). Restricted to virologically suppressed participants with CD4 >350 cells per microliter, herpes zoster rates were similar among PLWH aged younger than 60 years and aged 60 years and older in 2015 (6.6 vs 6.7/1000) but higher than all uninfected age groups. At study end, cumulative receipt of zoster vaccine for PLWH aged 60 years and older was less than half that of uninfected veterans: 98.7 vs 215.2/1000.

CONCLUSIONS

Herpes zoster rates among PLWH have markedly decreased, but, even in cART-treated individuals, remain 50% higher than uninfected adults. Lower rates of zoster vaccine receipt combined with high rates of herpes zoster support the need for a safe and effective vaccine against herpes zoster for PLWH, formal zoster vaccine guidelines for PLWH, and consideration for expanded use at younger ages.

652. What Is Blood Got to Do with It? Genetic Susceptibility to Norovirus and Rotavirus Infection: Results From the SUPERNOVA Network

Background

Histo-blood group antigens (HBGAs), whose expression is controlled in part by fucosyltransferase 2 (FUT2) and 3 (FUT3) genes, serve as receptors for norovirus and rotavirus. Individuals without functional FUT2 (nonsecretors) or FUT3 (Lewis-negative) genes may have decreased susceptibility to norovirus and rotavirus infections. As the prevalence of secretor and Lewis status can vary by race and ethnicity, we assessed this association in a US Veteran population.

Methods

Stool and saliva specimens were collected from acute gastroenteritis (AGE) cases and age- and time-matched controls through a multisite, active surveillance platform at four Veterans Affairs hospitals (Atlanta, Bronx, Houston, Los Angeles). Stool specimens were tested with the FilmArray Gastrointestinal Panel; norovirus and rotavirus positive specimens were genotyped. Saliva specimens were analyzed for HBGA expression by EIA using glycan-specific monoclonal antibodies and lectins. Chi-squared and Fisher’s exact tests were conducted to evaluate associations between secretor and Lewis status and infection with norovirus or rotavirus.

Results

From November 4, 2015–December 30, 2017, 670 AGE cases and 319 controls provided both stool and saliva specimens. Norovirus (21 GII.4 Sydney, 13 GII non-4, 7 GI, 10 untyped) and rotavirus (13 G12P[8], 1 G2P[4], 1 untyped) positive cases were more likely to be secretor positive (90% and 100%, respectively) compared with controls (76%) (P = 0.03 for both). Infections with GII.4 Sydney norovirus (P < 0.01) and G12P[8] rotavirus (P < 0.05) were significantly associated with secretor status. This association was not observed with other norovirus or rotavirus genotypes. No association was observed between Lewis status, race, or ethnicity and infection with norovirus or rotavirus.

Conclusion

Norovirus and rotavirus infections among a US Veteran population were associated with secretor status in a genotype-dependent manner, and with GII.4 Sydney norovirus and G12P[8] rotavirus, the most common strains. These associations are consistent with previously reported results, and suggest that the efficacy of interventions, such as vaccines, should include consideration of secretor status and predominantly circulating virus strains.

Disclosures

R. L. Atmar, Takeda Vaccines, Inc.: Investigator, Research grant. V. C. Marconi, ViiV: Investigator, Research support and Salary. Gilead: Investigator, Research support. Bayer: Investigator, Research support.

Provider verification of electronic health record receipt and nonreceipt of direct-acting antivirals for the treatment of hepatitis C virus infection

PURPOSE

Pharmacoepidemiologic studies using electronic health record data could serve an important role in assessing safety and effectiveness of direct-acting antiviral therapy for chronic hepatitis C virus (HCV) infection, but the validity of these data needs to be determined. We evaluated the accuracy of pharmacy fill records in the national Veterans Health Administration (VA) Corporate Data Warehouse (CDW) as compared to facility-level electronic health record.

METHODS

Patients prescribed a direct-acting antiviral regimen at five VA sites between 2014 and 2016 were randomly selected and reviewed. A random sample of patients with chronic HCV infection without evidence of HCV treatment during the study period also underwent chart review. We calculated positive predictive value and negative predictive value overall and by site.

RESULTS

Of the 501 patients who received a total of 2416 prescriptions, 494 were validated using data extracted from CDW 6 months after the study period, yielding a positive predictive value of 98.6% (95% confidence interval, 97.6%-99.6%). Of the 100 patients with chronic HCV infection without prescriptions for HCV treatment, 99 were confirmed not to have received antiviral treatment (negative predictive value, 99.0%; 95% confidence interval, 97.1%-100%).

CONCLUSIONS

These findings provide assurance to researchers who use national VA CDW data for retrospective cohort studies that the CDW contains accurate information on HCV therapies in the modern treatment era.

Failure to detect M. avium subspecies paratuberculosis in Johne's disease using a proprietary fluorescent in situ hybridization assay

Objectives

Mycobacterium avium subspecies paratuberculosis (MAP) causes Johne’s disease in ruminants. The “gold standard” of MAP detection is by culture, DNA sequencing possibly supplemented by identification of Ziehl–Neelsen positive mycobacteria. The purpose of this study was to evaluate a proprietary (Affymetrix™ RNA view^®) fluorescent in situ hybridization (FISH) assay for MAP RNA. Intestine from a steer with documented Johne’s disease was assayed according to the manufacturer’s instructions. Probes were custom designed for MAP and bovine β-actin (as the eukaryotic housekeeping gene) from published genomes. We attempt to prevent false positive signal in the “no-probe” control, by modifying wash solutions, using recommended hydrochloric acid titration and different fluorescent filters (TritC for Texas Red and “Hope” for Cy-5).

Results

Repetitively, false positive signal was observed in our “no probe” negative control. Attempts to correct this according to the manufacturers suggestions, and with multiple derivative techniques have been unsuccessful. It is concluded that when performed according to manufactures instruction and with multiple variations on the manufactures recommended suggestions to correct for false positive signal, that the Affymetrix™ RNA view^® cannot be used to detect MAP in pre-frozen intestine of cattle with Johne’s disease.

Electronic supplementary material

The online version of this article (10.1186/s13104-018-3601-5) contains supplementary material, which is available to authorized users.

Association of Viral Suppression With Lower AIDS-Defining and Non-AIDS-Defining Cancer Incidence in HIV-Infected Veterans: A Prospective Cohort Study

Background

Viral suppression is a primary marker of HIV treatment success. Persons with HIV are at increased risk for AIDS-defining cancer (ADC) and several types of non-AIDS-defining cancer (NADC), some of which are caused by oncogenic viruses.

Objective

To determine whether viral suppression is associated with decreased cancer risk.

Design

Prospective cohort.

Setting

Department of Veterans Affairs.

Participants

HIV-positive veterans (n = 42 441) and demographically matched uninfected veterans (n = 104 712) from 1999 to 2015.

Measurements

Standardized cancer incidence rates and Poisson regression rate ratios (RRs; HIV-positive vs. uninfected persons) by viral suppression status (unsuppressed: person-time with HIV RNA levels ≥500 copies/mL; early suppression: initial 2 years with HIV RNA levels <500 copies/mL; long-term suppression: person-time after early suppression with HIV RNA levels <500 copies/mL).

Results

Cancer incidence for HIV-positive versus uninfected persons was highest for unsuppressed persons (RR, 2.35 [95% CI, 2.19 to 2.51]), lower among persons with early suppression (RR, 1.99 [CI, 1.87 to 2.12]), and lowest among persons with long-term suppression (RR, 1.52 [CI, 1.44 to 1.61]). This trend was strongest for ADC (unsuppressed: RR, 22.73 [CI, 19.01 to 27.19]; early suppression: RR, 9.48 [CI, 7.78 to 11.55]; long-term suppression: RR, 2.22 [CI, 1.69 to 2.93]), much weaker for NADC caused by viruses (unsuppressed: RR, 3.82 [CI, 3.24 to 4.49]; early suppression: RR, 3.42 [CI, 2.95 to 3.97]; long-term suppression: RR, 3.17 [CI, 2.78 to 3.62]), and absent for NADC not caused by viruses.

Limitation

Lower viral suppression thresholds, duration of long-term suppression, and effects of CD4+ and CD8+ T-cell counts were not thoroughly evaluated.

Conclusion

Antiretroviral therapy resulting in long-term viral suppression may contribute to cancer prevention, to a greater degree for ADC than for NADC. Patients with long-term viral suppression still had excess cancer risk.

Primary Funding Source

National Cancer Institute and National Institute on Alcohol Abuse and Alcoholism of the National Institutes of Health.

Risk of Acute Liver Injury After Statin Initiation by Human Immunodeficiency Virus and Chronic Hepatitis C Virus Infection Status

Background

Patients with human immunodeficiency virus (HIV) and/or chronic hepatitis C virus (HCV) infection may be prescribed statins as treatment for metabolic/cardiovascular disease, but it remains unclear if the risk of acute liver injury (ALI) is increased for statin initiators compared to nonusers in groups classified by HIV/HCV status.

Methods

We conducted a cohort study to compare rates of ALI in statin initiators vs nonusers among 7686 HIV/HCV-coinfected, 8155 HCV-monoinfected, 17739 HIV-monoinfected, and 36604 uninfected persons in the Veterans Aging Cohort Study (2000-2012). We determined development of (1) liver aminotransferases >200 U/L, (2) severe ALI (coagulopathy with hyperbilirubinemia), and (3) death, all within 18 months. Cox regression was used to determine propensity score-adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) of outcomes in statin initiators compared to nonusers across the groups.

Results

Among HIV/HCV-coinfected patients, statin initiators had lower risks of aminotransferase levels >200 U/L (HR, 0.66 [95% CI, .53-.83]), severe ALI (HR, 0.23 [95% CI, .12-.46]), and death (HR, 0.36 [95% CI, .28-.46]) compared with statin nonusers. In the setting of chronic HCV alone, statin initiators had reduced risks of aminotransferase elevations (HR, 0.57 [95% CI, .45-.72]), severe ALI (HR, 0.15 [95% CI, .06-.37]), and death (HR, 0.42 [95% CI, .32-.54]) than nonusers. Among HIV-monoinfected patients, statin initiators had lower risks of aminotransferase increases (HR, 0.52 [95% CI, .40-.66]), severe ALI (HR, 0.26 [95% CI, .13-.55]), and death (HR, 0.19 [95% CI, .16-.23]) compared with nonusers. Results were similar among uninfected persons.

Conclusions

Regardless of HIV and/or chronic HCV status, statin initiators had a lower risk of ALI and death within 18 months compared with statin nonusers.

Mapping MOS-HIV to HUI3 and EQ-5D-3L in Patients With HIV

Objectives: The Medical Outcomes Study HIV Health Survey (MOS-HIV) is frequently used in HIV clinical trials; however, scores generated from the MOS-HIV are not suited for cost-effectiveness analyses as they do not assign utility values to health states. Our objective was to estimate and externally validate several mapping algorithms to predict Health Utilities Index Mark 3 (HUI3) and EQ-5D-3L utility values from the MOS-HIV. Methods: We developed and validated mapping algorithms using data from two HIV clinical trials. Data from the first trial (n = 367) formed the estimation data set for the HUI3 (4,610 observations) and EQ-5D-3L (4,662 observations) mapping algorithms; data from the second trial (n = 168) formed the HUI3 (1,135 observations) and EQ-5D-3L (1,152 observations) external validation data set. We compared ordinary least squares (OLS) models of increasing complexity with the more flexible two-part, beta regression, and finite mixture models. We assessed model performance using mean absolute error (MAE) and mean squared error (MSE). Results: The OLS model that used MOS-HIV dimension scores along with squared terms gave the best HUI3 predictions (mean observed 0.84; mean predicted 0.80; MAE 0.0961); the finite mixture model gave the best EQ-5D-3L predictions (mean observed 0.90; mean predicted 0.88; MAE 0.0567). All models produced higher prediction errors at the lower end of the HUI3 and EQ-5D-3L score ranges (<0.40). Conclusions: The proposed mapping algorithms can be used to predict HUI3 and EQ-5D-3L utility values from the MOS-HIV, although greater error may pose a problem in samples where a substantial proportion of patients are in poor health. These algorithms may be useful for estimating utility values from the MOS-HIV for cost-effectiveness studies when HUI3 or EQ-5D-3L data are not available.

A Low Peripheral Blood CD4/CD8 Ratio Is Associated with Pulmonary Emphysema in HIV

Objectives

The prevalence of emphysema is higher among HIV-infected (HIV+) individuals compared to HIV-uninfected persons. While greater tobacco use contributes, HIV-related effects on immunity likely confer additional risk. Low peripheral blood CD4+ to CD8+ T-lymphocyte (CD4/CD8) ratio may reflect chronic inflammation in HIV and may be a marker of chronic lung disease in this population. Therefore, we sought to determine whether the CD4/CD8 ratio was associated with chronic obstructive pulmonary disease (COPD), particularly the emphysema subtype, in a cohort of HIV+ subjects.

Methods

We performed a cross-sectional analysis of 190 HIV+ subjects enrolled in the Examinations of HIV Associated Lung Emphysema (EXHALE) study. Subjects underwent baseline laboratory assessments, pulmonary function testing and chest computed tomography (CT) analyzed for emphysema severity and distribution. We determined the association between CD4/CD8 ratio and emphysema, and the association between CD4/CD8 ratio and pulmonary function markers of COPD.

Results

Mild or greater emphysema (>10% lung involvement) was present in 31% of subjects. Low CD4/CD8 ratio was associated with >10% emphysema in multivariable models, adjusting for risk factors including smoking, current and nadir CD4 count and HIV RNA level. Those with CD4/CD8 ratio <0.4 had 6.3 (1.1–39) times the odds of >10% emphysema compared to those with a ratio >1.0 in fully adjusted models. A low CD4/CD8 ratio was also associated with reduced diffusion capacity (DLCO).

Conclusions

A low CD4/CD8 ratio was associated with emphysema and low DLCO in HIV+ subjects, independent of other risk factors and clinical markers of HIV. The CD4/CD8 ratio may be a useful, clinically available, marker for risk of emphysema in HIV+ subjects in the antiretroviral therapy (ART) era.

The Differential Impact of Emphysema on Respiratory Symptoms and 6-Minute Walk Distance in HIV Infection

BACKGROUND

Emphysema is more prevalent in HIV-infected (HIV+) patients independent of smoking behavior. Nonetheless, health effects of emphysema in this population are poorly understood. We determined whether emphysema is associated with a greater burden of pulmonary symptoms and a lower 6-minute walk distance (6MWD) in HIV+ compared with HIV-uninfected (HIV-) subjects.

METHODS

We performed a cross-sectional analysis of 170 HIV+ and 153 HIV- subjects in the Examinations of HIV-Associated Lung Emphysema (EXHALE) cohort study. Subjects completed a self-assessment of respiratory symptoms, pulmonary function testing, and 6MWD testing as well as a chest computed tomography to determine emphysema severity. We used regression models to determine the association of emphysema with respiratory symptoms and 6MWD in HIV+ subjects and compared this to HIV- subjects.

RESULTS

Models stratified by HIV status demonstrated an association between >10% radiographic emphysema and chronic cough and/or phlegm and 6MWD in HIV+ subjects. These associations persisted among the subset without airflow obstruction: those with emphysema had 4.2 (95% confidence interval: 1.3 to 14) times the odds of chronic cough and/or phlegm and walked 60 m (95% confidence interval: 26 to 93) less distance than those without emphysema. There was no association between >10% emphysema and symptoms or 6MWD in HIV- subjects.

CONCLUSIONS

In our cohort, >10% radiographic emphysema was associated with chronic cough and/or phlegm and lower 6MWD in HIV+ but not HIV- subjects. These findings were robust even among HIV+ subjects with milder forms of emphysema and those without airflow obstruction, highlighting the clinical impact of emphysema in these patients.

Immunological and infectious risk factors for lung cancer in US veterans with HIV: a longitudinal cohort study

BACKGROUND

HIV infection is independently associated with risk of lung cancer, but few data exist for the relation between longitudinal measurements of immune function and lung-cancer risk in people living with HIV.

METHODS

We followed up participants with HIV from the Veterans Aging Cohort Study for a minimum of 3 years between Jan 1, 1998, and Dec 31, 2012, and used cancer registry data to identify incident cases of lung cancer. The index date for each patient was the later of the date HIV care began or Jan 1, 1998. We excluded patients with less than 3 years' follow-up, prevalent diagnoses of lung cancer, or incomplete laboratory data. We used Cox regression models to investigate the relation between different time-updated lagged and cumulative exposures (CD4 cell count, CD8 cell count, CD4/CD8 ratio, HIV RNA, and bacterial pneumonia) and risk of lung cancer. Models were adjusted for age, race or ethnicity, smoking, hepatitis C virus infection, alcohol use disorders, drug use disorders, and history of chronic obstructive pulmonary disease and occupational lung disease.

FINDINGS

We identified 277 cases of incident lung cancer in 21 666 participants with HIV. In separate models for each time-updated 12 month lagged, 24 month simple moving average cumulative exposure, increased risk of lung cancer was associated with low CD4 cell count (p trend=0·001), low CD4/CD8 ratio (p trend=0·0001), high HIV RNA concentration (p=0·004), and more cumulative bacterial pneumonia episodes (12 month lag only; p trend=0·0004). In a mutually adjusted model including these factors, CD4/CD8 ratio and cumulative bacterial pneumonia episodes remained significant (p trends 0·003 and 0·004, respectively).

INTERPRETATION

In our large HIV cohort in the antiretroviral therapy era, we found evidence that dysfunctional immune activation and chronic inflammation contribute to the development of lung cancer in the setting of HIV infection. These findings could be used to target lung-cancer prevention measures to high-risk groups.

FUNDING

US National Institutes of Health.

Time trends in cancer incidence in persons living with HIV/AIDS in the antiretroviral therapy era: 1997-2012

OBJECTIVE

Utilizing the Veterans Aging Cohort Study, the largest HIV cohort in North America, we conducted one of the few comprehensive comparisons of cancer incidence time trends in HIV-infected (HIV+) versus uninfected persons during the antiretroviral therapy (ART) era.

DESIGN

Prospective cohort study.

METHODS

We followed 44 787 HIV+ and 96 852 demographically matched uninfected persons during 1997-2012. We calculated age-, sex-, and race/ethnicity-standardized incidence rates and incidence rate ratios (IRR, HIV+ versus uninfected) over four calendar periods with incidence rate and IRR period trend P values for cancer groupings and specific cancer types.

RESULTS

We observed 3714 incident cancer diagnoses in HIV+ and 5760 in uninfected persons. The HIV+ all-cancer crude incidence rate increased between 1997-2000 and 2009-2012 (P trend = 0.0019). However, after standardization, we observed highly significant HIV+ incidence rate declines for all cancer (25% decline; P trend <0.0001), AIDS-defining cancers (55% decline; P trend <0.0001), nonAIDS-defining cancers (NADC; 15% decline; P trend = 0.0003), and nonvirus-related NADC (20% decline; P trend <0.0001); significant IRR declines for all cancer (from 2.0 to 1.6; P trend <0.0001), AIDS-defining cancers (from 19 to 5.5; P trend <0.0001), and nonvirus-related NADC (from 1.4 to 1.2; P trend = 0.049); and borderline significant IRR declines for NADC (from 1.6 to 1.4; P trend = 0.078) and virus-related NADC (from 4.9 to 3.5; P trend = 0.071).

CONCLUSION

Improved HIV care resulting in improved immune function most likely contributed to the HIV+ incidence rate and the IRR declines. Further promotion of early and sustained ART, improved ART regimens, reduction of traditional cancer risk factor (e.g. smoking) prevalence, and evidence-based screening could contribute to future cancer incidence declines among HIV+ persons.

Abstract 4308: Multiplicative interaction between HIV infection status and FIB-4 in prediction of hepatocellular carcinoma risk

Purpose: FIB-4 is an established marker of liver fibrosis and cirrhosis, calculated from platelet count, alanine transaminase, aspartate transaminase, and age. We previously found baseline FIB-4 to be strongly associated with hepatocellular carcinoma (HCC) risk among HIV-infected (HIV+) patients in the US; a similar finding was reported among persons who consume alcohol or are chronic hepatitis B virus (HBV) carriers in South Korea. Longitudinal associations between FIB-4 and HCC risk have not yet been explored. We aimed to expand our prior investigation by including uninfected patients, using time-updated FIB-4, and testing for multiplicative interaction between HIV status and FIB-4 in the prediction of HCC risk. We hypothesized that the relationship between FIB-4 and HCC risk would differ by HIV status.

Methods: We tested this hypothesis in the Veterans Aging Cohort Study, an open cohort that enrolls HIV+ veterans when they begin HIV care in the Veterans Health Administration and matches two uninfected patients by age, sex, race/ethnicity, and clinical site. We used proportional hazards regression models with time-varying covariates to calculate hazard ratios (HR) and 95% confidence intervals (CI) for FIB-4, adjusted for HCC risk factors (age, sex, race, hepatitis C virus (HCV) infection, HBV infection, smoking, alcohol, BMI, and diabetes). We used the counting process to create time-updated FIB-4 intervals and examined one-, three-, and five-year lagged FIB-4. We identified incident HCC cases from the VA Central Cancer Registry and determined hepatitis C virus and hepatitis B virus status from laboratory results. We defined low (3.25) as previously established.

Results: Between 2000 and 2012, among 37,158 HIV+ subjects, 202 developed HCC. Among 78,339 uninfected subjects, 207 developed HCC. There was a significant multiplicative interaction between HIV status and one-year lagged FIB-4 (interaction p = 0.0015). High FIB-4 was a stronger predictor of HCC in the uninfected than in HIV+. Among uninfected, the adjusted HR was 6.9 (95% CI: 3.4, 12.5) for intermediate FIB-4 and 40.0 (95% CI: 22.3, 71.8) for high FIB-4 compared to uninfected with low FIB-4. Among HIV+, with the same reference group (uninfected with low FIB-4), the adjusted HR was 2.1 (95% CI: 1.0, 4.4) for low FIB-4, 6.4 (95% CI: 3.5, 11.7) for intermediate FIB-4, and 23.7 (95% CI: 13.1, 42.9) for high FIB-4. There was no interaction between FIB-4 and HCV status (p = 0.92). Results were qualitatively similar using a three- or five-year lag.

Conclusions: Calculated from routine, non-invasive laboratory tests, FIB-4 is a strong, independent HCC risk factor in both HIV+ and uninfected subjects after adjustment for other HCC risk factors. FiB-4 appears to be a stronger risk factor in uninfected than in HIV+.

Citation Format: Lesley S. Park, Janet P. Tate, Vincent Lo Re, Adeel A. Butt, Cynthia Gibert, Matthew Bidwell Goetz, Sheldon T. Brown, Joseph Lim, David Rimland, Jennifer S. Lee, Amy C. Justice, Robert Dubrow. Multiplicative interaction between HIV infection status and FIB-4 in prediction of hepatocellular carcinoma risk. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4308.

Predicting Risk of End-Stage Liver Disease in Antiretroviral-Treated Human Immunodeficiency Virus/Hepatitis C Virus-Coinfected Patients

Background.  End-stage liver disease (ESLD) is an important cause of morbidity among human immunodeficiency virus (HIV)/hepatitis C virus (HCV)-coinfected patients. Quantifying the risk of this outcome over time could help determine which coinfected patients should be targeted for risk factor modification and HCV treatment. We evaluated demographic, clinical, and laboratory variables to predict risk of ESLD in HIV/HCV-coinfected patients receiving antiretroviral therapy (ART). Methods.  We conducted a retrospective cohort study among 6016 HIV/HCV-coinfected patients who received ART within the Veterans Health Administration between 1997 and 2010. The main outcome was incident ESLD, defined by hepatic decompensation, hepatocellular carcinoma, or liver-related death. Cox regression was used to develop prognostic models based on baseline demographic, clinical, and laboratory variables, including FIB-4 and aspartate aminotransferase-to-platelet ratio index, previously validated markers of hepatic fibrosis. Model performance was assessed by discrimination and decision curve analysis. Results.  Among 6016 HIV/HCV patients, 532 (8.8%) developed ESLD over a median of 6.6 years. A model comprising FIB-4 and race had modest discrimination for ESLD (c-statistic, 0.73) and higher net benefit than alternative strategies of treating no or all coinfected patients at relevant risk thresholds. For FIB-4 >3.25, ESLD risk ranged from 7.9% at 1 year to 26.0% at 5 years among non-blacks and from 2.4% at 1 year to 14.0% at 5 years among blacks. Conclusions.  Race and FIB-4 provided important predictive information on ESLD risk among HIV/HCV patients. Estimating risk of ESLD using these variables could help direct HCV treatment decisions among HIV/HCV-coinfected patients.

Impact of defined clinical population and missing data on temporal trends in HIV viral load estimation within a health care system

OBJECTIVES

Community viral load (CVL) estimates vary based on analytic methods. We extended the CVL concept and used data from the Veterans Health Administration (VA) to determine trends in the health care system viral load (HSVL) and its sensitivity to varying definitions of the clinical population and assumptions regarding missing data.

METHODS

We included HIV-infected patients in the Veterans Aging Cohort Study, 2000-2010, with at least one documented CD4 count, HIV-1 RNA or antiretroviral prescription (n = 37 318). We created 6-month intervals including patients with at least one visit in the past 2 years. We assessed temporal trends in clinical population size, patient clinical status and mean HSVL and explored the impact of varying definitions of the clinical population and assumptions about missing viral load.

RESULTS

The clinical population size varied by definition, increasing from 16 000-19 000 patients in 2000 to 23 000-26 000 in 2010. The proportion of patients with suppressed HIV-1 RNA increased over time. Over 20% of patients had no viral load measured in a given interval or the past 2 years. Among patients with a current HIV-1 RNA, mean HSVL decreased from 97 800 HIV-1 RNA copies/mL in 2000 to 2000 copies/mL in 2010. When current HIV-1 RNA data were unavailable and the HSVL was recalculated using the last available HIV-1 RNA, HSVL decreased from 322 300 to 9900 copies/mL. HSVL was underestimated when using only current data in each interval.

CONCLUSIONS

The CVL concept can be applied to a health care system, providing a measure of health care quality. Like CVL, HSVL estimates depend on definitions of the clinical population and assumptions about missing data.