United States Veteran Population Research Articles

Epidemiology of Diabetic Kidney Disease among US Veterans.

With a large number of patients and high mortality, diabetic kidney disease (DKD) imposes a significant burden on US health care. Although diabetes is the leading cause of chronic kidney disease and complications, the epidemiology of DKD in the contemporary US veteran population is generally unknown. We aimed to estimate the rate of DKD progression and to measure the general epidemiology of DKD in the United States veteran population. We performed a retrospective observational research using electronic health-care records and administrative databases. The DKD patient cohort was abstracted from the Veterans Health Administration health-record data from January 2016 to March 2022. We defined DKD patients using the laboratory test data based on Kidney Disease: Improving Global Outcomes (KDIGO) clinical practice guidelines. Summary statistics include the five-year cumulative incidence of progression to an advanced stage from the DKD stage at the cohort entry date and prevalence at a series of single time points. A total of 685,288 patients (male [96%], mean age 62 years, Caucasian [64%], non-Hispanic [87%]) met our eligibility criteria. The 5-year cumulative incidence of progression to an advanced DKD stage or all-cause death from DKD stages G1 A2/A3, G2 A2/A3, G3a, and G3b were 52.0%, 47.4%, 50.5%, and 60.9%, respectively. In sum, 594,082 patients were classified as moderate or high risk as per KDIGO guidelines in 2021, and stages G3a and G3b accounted for 51.2% and 25.3%, respectively, of cases. More than half of DKD patients underwent a stage progression or death within 5 years. A substantial number of DKD patients at an earlier stage might be left undetermined. The study findings warrant a revision of DKD patient identification and management in US veterans.

Effects of Concomitant CABG on Outcomes in Veterans Who Require Surgery for Endocarditis.

Infective Endocarditis (IE) is a complicated disease frequently accompanied by coronary artery disease (CAD) though no clear guidelines exist for when concomitant revascularization should be undertaken once valve surgery is indicated. Data on this topic within the United States (US) Veteran population, who have unique healthcare needs when compared to the civilian population, is sparse. We investigated the impact of concomitant coronary artery bypass grafting (CABG) on morbidity and mortality in US Veterans requiring surgical management of IE. We identified 489 patients who underwent surgical management of IE between January 1 2010 and December 31 2020 at any of 43 Veterans Affairs (VA) cardiac surgery centers in the US. Patients were stratified based on who underwent concomitant CABG at the time of operation. Primary outcomes included the occurrence of postoperative myocardial infarction (MI), stroke, or mortality. Continuous variables were compared using independent t-tests or Mann Whitney U tests, and categorical variables were compared using the Chi square test. Cox proportional-hazard models were used to calculate risk for primary outcomes based on group. 61 patients (12.5%) underwent concomitant CABG for CAD. After adjusting for significant covariates, patients who underwent CABG had a higher long-term risk of MI (adjusted hazard ratios (aHR) 2.37, 95% CI: 1.29-4.35, p = 0.005) and higher risk of MI at 30-days (aHR 2.34, 95% CI: 1.06-5.19, p = 0.035). Concomitant CABG was not associated with long-term stroke or death, 30-day stroke or death, or perioperative complications. On sub-analysis of patients with moderate to severe CAD, rates of MI were higher in the CABG group at 30 days (25.9 vs. 3.4%, p = 0.016) and 1 year (33.3 vs. 3.4%, p = 0.004), though not long-term. The mean number of grafts was 1.51 ± 0.76, with only one graft performed in 65.6% (40/61) of patients. Concomitant CABG at the time of operation for IE was associated with increased risk of MI at 30-day and long-term, though most CABGs involved a low number of grafts. It was not associated with 30-day stroke or death, long term stroke or death, or perioperative complications. The optimal treatment of CAD noted during preoperative evaluation for veterans undergoing surgery for IE remains unclear.

Space-time clustering of COVID-19 cases in the United States veteran population

To assess the distribution and clustering of coronavirus disease 2019 (COVID-19) testing and incidence over space and time, U.S. Department of Veteran's Affairs (VA) data were used to describe where and when veterans experienced highest proportions of test positivity. Data for 6,342,455 veterans who utilized VA services between January 1, 2018, and September 30, 2021, were assessed for COVID-19 testing and test positivity. Testing and positivity proportions by county were mapped and focused-cluster tests identified significant clustering around VA facilities. Spatial cluster analysis also identified where and when veterans experienced highest proportions of test positivity. Within the veterans study population and our time window, 21.3% received at least one COVID-19 test, and 20.4% of those tested had at least one positive test. There was statistically significant clustering of testing around VA facilities, revealing regional variation in testing practices. Veterans experienced highest test positivity proportions between November 2020 and January 2021 in a cluster of states in the Midwest, compared to those who received testing outside of the identified cluster (RR: 3.45). Findings reflect broad regional trends in COVID-19 positivity which can inform VA policy and resource allocation. Additional analysis is needed to understand patterns during Delta and Omicron variant periods.

Effect of COVID-19 and its vaccines on surgical and postsurgical mortality, ICU admission and 90-day readmission for elective surgical procedures in a United States veteran population

BackgroundWe investigated how COVID-19 infection and vaccination impact elective surgical outcomes. MethodsWe retrospectively compared pre-pandemic (P) veterans to those with COVID (C) more than three weeks preoperatively or no COVID (NC) history after carotid endarterectomy, CABG, hip replacement, or colectomy. Subgroup analysis considered vaccination. Age and sex propensity matching, and conditional logistic regression analyzed one-year-mortality, 90-day-readmission, and ICU requirements among 519 ​C, 1038 NC, and 2076 ​P, culled from 61,641 veterans. ResultsNC, C, and P had similar ICU requirements and mortality, although NC required fewer readmissions. However, NC immunized at least once were readmitted and died less commonly than C who received at least one immunization. ConclusionsSARS-CoV-2 history increased readmission without affecting ICU requirement or mortality. Further studies should evaluate whether the worse outcomes in postoperative patients with histories of both COVID infection and one vaccination reflect the effects of incomplete vaccination or dataset limitations.

Epidemiology and survival trends of lung carcinoids in the veteran population.

e21049 Background: Lung carcinoids (LC) continue to increase in prevalence and existing data shows a female predominance of these tumors, but relevant epidemiologic data for heterogeneous populations is limited. In this study, we describe the epidemiology of LC in the United States (US) Veteran population. Methods: In this retrospective study, we searched Veteran Affairs Cancer Cube Registry (VACCR) for LC cases diagnosed between 2000 and 2017 and their baseline characteristics. Survival rates were analyzed across all baseline characteristics to identify important prognostic factors and results were compared with Surveillance, Epidemiology, and End Results cancer database (SEER). Data was analyzed via chi-square and Fischer exact probability tests (level of significance at < 0.05). Results: We identified 846 LC cases in VACCR (91% males), and 8,851 LC cases in SEER (32% males). Compared to SEER, VACCR data had more black patients (12% vs 8%), less cases with loco-regional disease (56% vs 84% in SEER) and same proportion of lower lobe tumors (40%). The annual incidence rate of LC among all lung cancers in Veterans tripled from 2000 to 2017 (0.3% to 0.9%). No racial disparities in treatment were noted among the Veterans. Male-specific 5-year survival rate was 18% lower in VACCR compared to SEER (61% vs 79%). Univariate analysis of both databases showed a statistically significant association of survival with age, primary tumor site and gender (p < 0.05 for all) (Table 1), with advanced age, upper lobe LC and male gender associated with worse survival. SEER subgroup analyses also showed lower 5-year survival rates for males across all baseline characteristics. Overall, black race appeared to be associated with worse prognosis, but the results did not reach statistical significance for VACCR data. Conclusions: Our study showed that US Veteran population, consisting of older males with more comorbidities, LC have lower survival rates than SEER population with more female LC cases. Advanced age, upper lobe predominant disease, and advanced stage were associated with worse survival. Both SEER and VACCR data suggest that male sex is a poor prognostic factor for LC. [Table: see text]

Lumbar spine surgery reduces postoperative opioid use in the veteran population.

The United States has been facing a worsening opioid epidemic over the past two decades. The veteran population represents a large and vulnerable group with a higher burden of mental health comorbidities. The purpose of this study was to analyze the impact of lumbar spine surgery on postoperative opioid usage in the United States veteran population. A retrospective cohort study was conducted using the Veterans Affairs Informatics and Computing Infrastructure database. Patients who underwent lumbar spine surgery were stratified into three groups by their preoperative opioid claims within 365 days of surgery. Postoperative cumulative morphine milligram equivalents (MME) were tracked for each group and the paired Wilcoxon signed rank test was used to compare cumulative preoperative MME (days -365-0) to cumulative postoperative MME (days 91-455). At one year, 30.6% of patients in the high preoperative opioid group and 73.1% of patients in the low preoperative opioid group were no longer using opioids. In the opioid naive cohort, 10.0% of patients were still using opioids at one year. Among all patients, median cumulative postoperative MME was significantly less than median cumulative preoperative MME (P<0.001). High preoperative opioid usage of more than 3 claims was most significantly associated with continued postoperative opioid usage (odds ratio 12.55, P<0.001). From 2010 to 2020 the proportion of patients with preoperative opioid claims decreased (58.8% to 34.8%). In the veteran population, lumbar spine surgery was effective in getting 50% of patients who were on opioids preoperatively to discontinue opioids postoperatively. Even minimal exposure to opioids preoperatively resulted in a 2.69-time increase in risk of being on opioids at one year versus opioid naive patients. This study affirms that despite being a high-risk population, the veteran population has a similar response to lumbar spine surgery as the general population in regards to opioid dependence.

S409 The Prevalence of Dysplasia in Ultrashort Barrett's Esophagus in a United States Veteran Population

Introduction: Surveillance of Barrett’s esophagus (BE), the only known precursor to esophageal adenocarcinoma (EA), is the basis for secondary prevention of EA. Length of BE has been associated with EA risk, and current guidelines recommend against biopsies of ultrashort BE (i.e., BE length < 1cm), however this is based on limited evidence. Our study aims to characterize the prevalence of dysplasia in ultrashort BE. Methods: We conducted a retrospective cohort study at the Houston VA of consecutive patients with new BE diagnosis from 11/1990-1/2019 with follow-up through 12/2021. We classified ultrashort BE as length < 1cm at initial BE-diagnosing (index) EGD. We defined persistent ultrashort BE as those with ultrashort BE on index EGD and all follow-up EGDs through the entire study period, requiring 2 or more EGDs. We calculated the prevalence of any dysplasia (indefinite [IND], low-grade [LGD], and high-grade [HGD]) and definite dysplasia (LGD and HGD). We examined the association of age, race, gender, body mass index (BMI), smoking history, and alcohol history with dysplasia in ultrashort BE and BE ≥1cm with chi-square test. Results: Our cohort had 741 patients with BE. The mean follow-up time was 4.6 years (standard deviation, 5.5 years). Ultrashort BE was present in 20.2% (n=150) of BE patients. Of the 150 with ultrashort BE, 131 underwent at least two EGDs. Persistent ultrashort BE was present in 92 patients with BE (12.4%). The prevalence of any dysplasia and definite dysplasia were 24.0% (n=36, 29 IND, 2 LGD, 5 HGD) and 4.7% (n=7) among those with ultrashort BE, and 52.6% and 23.8% respectively among those with BE ≥1cm. Of those with ultrashort BE, 4 (2.7%) developed any dysplasia after the index EGD. Of those with persistent ultrashort BE, the prevalence of any dysplasia was 21.7% (n=20, 16 IND, 2 LGD, 2 HGD), while the prevalence of definite dysplasia was 4.4% (n=4). All cases of dysplasia in persistent ultrashort BE were diagnosed at the index EGD. Normal BMI was associated with any dysplasia among those with ultrashort BE (p-value 0.003), while non-Hispanic White race/ethnicity was associated with any dysplasia among those without ultrashort BE (p-value 0.009; Table). Conclusion: While the prevalence of dysplasia is lower than that for BE ≥1cm, the prevalence of dysplasia in ultrashort BE in this study was as high as 24.0%. These patients may not be safely excluded from surveillance. Further studies should be conducted to confirm these findings. Table 1. - Sociodemographic and clinical characteristics of any dysplasia (indefinite for dysplasia, low-grade dysplasia, and high-grade dysplasia) among those with and without ultrashort Barrett’s esophagus Ultrashort BE < 1cm at Index EGD BE ≥1cm at Index EGD No DysplasiaN=114N (%) Any dysplasiaN = 36N (%) p-value No DysplasiaN = 280N (%) Any DysplasiaN = 311N (%) p-value Age < 60 years 45 (39.5%) 9 (25.0%) 0.115 94 (33.6%) 104 (33.4%) 0.973 60+ years 69 (60.5%) 27 (75.0%) 186 (66.4%) 207 (66.6%) Sex Male 106 (93.0%) 34 (94.4%) 0.759 269 (96.1%) 304 (98.1%) 0.147 Female 8 (7.0%) 2 (5.6%) 11 (3.9%) 6 (1.9%) Race Non-Hispanic White 86 (75.4%) 26 (72.2%) 0.47 216 (77.1%) 264 (85.9%) 0.009 African American 17 (14.9%) 4 (11.1%) 36 (12.9%) 16 (5.1%) Hispanic 11 (9.7%) 6 (16.7%) 26 (9.3%) 30 (9.7%) Other/Missing 0 (0.0%) 0 (0.0%) 2 (0.7%) 1 (0.3%) BMI Categories Normal (< 25) 18 (15.8%) 11 (30.6%) 0.003 52 (18.6%) 51 (16.4%) 0.878 Overweight (25-29.9) 38 (33.3%) 18 (32.1%) 106 (37.9%) 126 (40.5%) Obese (30+) 58 (50.9%) 7 (19.4%) 120 (42.9%) 132 (42.4%) Missing 0 (0.0%) 0 (0.0%) 2 (0.7%) 2 (0.6%) Smoking Never Smoker 29 (25.4%) 8 (22.2%) 0.813 78 (27.9%) 83 (26.7%) 0.429 Former Smoker 59 (51.8%) 18 (50.0%) 121 (43.2%) 150 (48.2%) Current Smoker 26 (22.8%) 10 (27.8%) 81 (28.9%) 78 (25.1%) Alcohol Use Never Alcohol use 36 (31.6%) 12 (33.3%) 0.862 128 (45.7%) 115 (37.0%) 0.088 Former Alcohol Use 28 (24.6%) 10 (27.8%) 58 (20.7%) 70 (22.5%) Current Alcohol Use 50 (43.9%) 14 (38.9%) 94 (33.6%) 126 (40.5%) Abbreviations: BE (Barrett's esophagus), cm (centimeter), BMI (body mass index)

Pharmacoepidemiology, Machine Learning, and COVID-19: An Intent-to-Treat Analysis of Hydroxychloroquine, With or Without Azithromycin, and COVID-19 Outcomes Among Hospitalized US Veterans.

Hydroxychloroquine (HCQ) was proposed as an early therapy for coronavirus disease 2019 (COVID-19) after in vitro studies indicated possible benefit. Previous in vivo observational studies have presented conflicting results, though recent randomized clinical trials have reported no benefit from HCQ amongst hospitalized COVID-19 patients. We examined the effects of HCQ alone, and in combination with azithromycin, in a hospitalized COVID-19 positive, United States (US) Veteran population using a propensity score adjusted survival analysis with imputation of missing data. From March 1, 2020 through April 30, 2020, 64,055 US Veterans were tested for COVID-19 based on Veteran Affairs Healthcare Administration electronic health record data. Of the 7,193 positive cases, 2,809 were hospitalized, and 657 individuals were prescribed HCQ within the first 48-hours of hospitalization for the treatment of COVID-19. There was no apparent benefit associated with HCQ receipt, alone or in combination with azithromycin, and an increased risk of intubation when used in combination with azithromycin [Hazard Ratio (95% Confidence Interval): 1.55 (1.07, 2.24)]. In conclusion, we assessed the effectiveness of HCQ with or without azithromycin in treating patients hospitalized with COVID-19 using a national sample of the US Veteran population. Using rigorous study design and analytic methods to reduce confounding and bias, we found no evidence of a survival benefit from the administration of HCQ.

Impact of Age on Treatment and Outcome in Newly Diagnosed DLBCL (Diffuse Large B-cell Lymphoma) Patients in the United States Veteran Population (2011-2017)

Introduction: Diffuse large B-cell lymphoma (DLBCL), is predominantly diagnosed in the elderly with a median age of diagnosis approaching the seventh decade of life. The prognosis for DLBCL has improved for all age groups, but less so for those over 75 years of age. The VHA (Veterans Health Administration) is one of the largest integrated provider of cancer care in the United States and its population, on average, is older than the general US population, giving us an unique advantage in exploring outcomes in elderly population. Methods: We reviewed 2036 medical records on patients that had a diagnosis code of some form of lymphoma between 2011 to 2017. Patients were randomly selected. Inclusion criteria was any veteran with atleast one entry in their records of selected ICD-9 and ICD-10 codes for lymphoma. Exclusion criteria included primary CNS lymphoma, other low grade variant lymphomas, diagnosis and treatment outside VHA, inability to determine if patient record met study criteria or inability to fill in critical fields of interest for the study. 971 patients were included. Data was manually abstracted by trained researchers. The Wilcoxon-Mann-Whitney test was used to compare median Overall Survival (OS) between two groups. All statistical comparisons were made using the R statistical analysis package. A level of significance of 0.05 was used for all the tests. Results: Of the 971 patients that met the inclusion criteria, 739 (76.1%) were &amp;lt;75 years and 232 (23.9%) were ≥75 years. Larger number of veterans were diagnosed at Stage III-IV (67% in &amp;lt;75 years and 67.7% in ≥75 years, p=0.76) with higher IPI score &amp;gt;3 (50.1 % in &amp;lt;75 years and 60.4% in ≥75 years, p=0.0005). Further descriptive comparison is outlined in Table 1. Patients in the &amp;lt;75 years age group received more lines of chemotherapy (p&amp;lt;0.0001). The ≥75 years older age group was more likely to have no treatment or non-chemo treatment (15.5% vs 3.9%) and the under 75 group was more likely to have 2 or more lines of treatment (8.9% vs 2.6%). For those who received chemotherapy, 82.4% in &amp;lt;75 years vs 76.3% in ≥75 years completed at least 4 cycles of therapy (p=0.07). However, 1 year, 2 years and median OS, was statistically different between the two age groups for all three measurements (p&amp;lt;0.0001) and survival decreases as age at diagnosis increases. (Table 2, Figure 1). Conclusions: Nearly 1/4th of the patient population were older than 75 years, and despite receiving comparable lines of chemotherapy, had lower survival when compared to patients who were &amp;lt;75 years. Previous studies (Lee et al, Cancer 2003 &amp; Kenneth R.Carson et al, Blood 2012) have reported the role of an anthracycline or treatment related mortality contributing to inferior outcomes in the elderly population. While historical data supports CHOP at maximal doses in elderly, a re-assessment of dose intensity, role of anthracyclines and finding a balance between short-term efficacy and safety is a priority for this age group given increasing human longevity. Disclosures No relevant conflicts of interest to declare.

Comparing the impact of high-dose versus standard dose influenza vaccines on hospitalization cost for cardiovascular and respiratory diseases: Economic assessment in the US Veteran population during 5 respiratory seasons using an instrumental variable method

ObjectivesCost savings associated with high-dose (HD) as compared to standard-dose (SD) influenza vaccination in the United States (US) Veteran’s Health Administration (VHA) population have been attributed to better protection against hospitalization for cardiac and respiratory diseases. The relative contribution of each of these disease categories to the reported savings remains to be explored. MethodsDuring a recently completed study of HD versus SD vaccine effectiveness (conducted in the VHA over five respiratory seasons from 2010/11 through 2014/15), we collected cost data for all healthcare services provided at both VHA and Medicare-funded facilities. In that analysis, we compared the costs of vaccination and hospital care for patients admitted with either cardiovascular or respiratory disease. Treatment selection bias and other confounding factors were adjusted using an instrumental variable (IV) method. In this brief report we use the same study cohort and methods to stratify the results by patients admitted for cardiovascular disease (CVD) and those admitted for respiratory disease. ResultsWe analyzed 3.5 million SD and 0.16 million HD person-seasons. The IV-adjusted rVEs were 14% (7–20%) against hospitalizations for CVD and 15% (5–25%) against respiratory hospitalizations. Net cost savings per HD recipient were $138 ($66–$200) for CVD related hospitalizations and $62 ($10–$107) for respiratory disease related hospitalizations. ConclusionsIn the US VHA population, the reduction in hospitalizations for CVD over five respiratory seasons contributed twice the cost savings (per HD recipient) of the reduction in hospitalizations for respiratory disease.

SUN-263 COMPARISON OF MORTALITY AND END-STAGE RENAL DISEASE (ESRD) AMONG RACIAL/ETHNIC GROUPS IN THE U.S. VETERAN INCIDENT CKD POPULATION

Using an incident, rather than prevalent, chronic kidney disease (CKD) population is essential when the research purpose is to understand the difference in CKD progression and associated risk factors among racial/ethnic groups. We recently constructed a national incident CKD cohort from the United States (US) veteran population. Here, we report mortality and progression to ESRD among racial/ethnic groups. The incident CKD cohort includes all subjects who had two estimated glomerular filtration rates (eGFRs) <60 mL/min/1.73 m2 with at least 90 days apart between 1/1/2002 and 5/01/2011 in the US Veteran Affairs database. eGFRs were calculated using the CKD Epidemiology Collaboration (CKD-EPI) estimating equation. The first date of laboratory occurrences serves as the index date. Subjects were excluded if they had been in the database for <2 years prior to the index date, did not have any eGFR values of >60 during the prior two years, or had prior ESRD (transplantation or dialysis). These exclusion criteria ensure that the index date was close to the true CKD onset. All subjects were followed for a fixed length of 5 years for outcomes including pre-ESRD death, ESRD event, or death after ESRD. Percentages of events within 5 years of index date and hazard ratios were examined. Of the 498,439 subjects included, 413,963 were White, 59,082 Black, 16,946 Hispanic, 2177 American Indian or Alaska Native (AI), 1894 Asian, and 4377 Native Hawaiian or Pacific Islander (NH). These groups had similar mean eGFR levels at entry (range 52-53 ml/min/1.73m2) and gender distributions (96-97% male). Findings: 1) At CKD onset Blacks were the youngest (mean age 51.7) while Whites and Asians were the oldest (both at 53). 2) In all age groups, Asians had substantially lower percentages of pre-ESRD deaths than other race groups which had relatively similar percentages (Table). Blacks and Hispanics had greater percentages of ESRD events while Whites had substantially lower percentages of ESRD. 3) As for competing risks, all races were more likely to die than to develop ESRD, except for ages under 50 years where Asians and Blacks were more likely to develop ESRD. 4) In the pre-ESRD and ESRD periods combined, Asians had the lowest percentage of total deaths in all age groups, Hispanics had the greatest percentage of total deaths in ages under 50, and Blacks had the greatest percentage of total deaths in ages above 50. 5) The hazard ratios for other races vs. Whites were little changed with adjustment for age, baseline eGFR, and gender. TablePercentages of events within 5 years of index date by race/ethnicity and ageAge groupRace/ethnicity% pre-ESRD death% ESRD event% total deaths in both pre-ESRD and ESRD18 - 50White15.55.117.0Black14.315.117.8Hispanic16.313.220.2American Indian (AI)16.812.617.9Asian9.912.316.0Native Hawaiian or Pacific Islander (NH)16.110.317.451 - 70White18.91.819.5Black19.56.421.3Hispanic18.35.820.2AI19.34.520.5Asian9.23.29.9NH15.52.716.171 - 100White30.20.630.5Black34.41.335.1Hispanic30.01.030.4AI27.11.327.8Asian25.70.225.9NH28.80.929.2 Open table in a new tab In this incident cohort of US veterans with new onset CKD, the risks of death and developing ESRD differ by racial/ethnic groups. Research to assess biological and non-biological determinants for these differences will lead to more tailored treatment that may improve outcomes for all patients with CKD.

Economic assessment of a high-dose versus a standard-dose influenza vaccine in the US Veteran population: Estimating the impact on hospitalization cost for cardio-respiratory disease

ObjectiveTo compare the economic impact of high-dose trivalent (HD) versus standard-dose trivalent (SD) influenza vaccination on direct medical costs for cardio-respiratory hospitalizations in adults aged 65 years or older enrolled in the United States (US) Veteran’s Health Administration (VHA). MethodsLeveraging a relative vaccine effectiveness study of HD versus SD over five respiratory seasons (2010/11 through 2014/15), we collected cost data for healthcare provided to the same study population both at VHA and through Medicare services. Our economic assessment compared the costs of vaccination and hospital care for patients experiencing acute cardio-vascular or respiratory illness. ResultsWe analyzed 3.5 million SD and 158,636 HD person-seasons. The average cost of HD and SD vaccination was $23.48 (95% CI: $21.29 - $25.85) and $12.21 (95% CI: $11.49 - $13.00) per recipient, respectively, while the hospitalization rates for cardio-respiratory disease in HD and SD recipients were 0.114 (95% CI: 0.108–0.121) and 0.132 (95% CI: 0.132–0.133) per person-season, respectively. Attributing the average cost per hospitalization of $11,796 (95% CI: $11,685 - $11,907) to the difference in hospitalization rates, we estimated savings attributable to HD to be $202 (95% CI: $115 – $280) per vaccinated recipient. ConclusionsFor the five-season period of 2010/11 through 2014/15, HD influenza vaccination was associated with net cost savings due to fewer hospitalizations, and therefore lower direct medical costs, for cardio-respiratory disease as compared to SD influenza vaccination in the senior US VHA population.

Heritability and individuality of the plasma sodium concentration: a twin study in the United States veteran population.

Little is known about the population genetics of water balance. A recent meta-genome-wide association study on plasma sodium concentration identified novel loci of high biological plausibility, yet heritability of the phenotype has never been convincingly shown in European ancestry. The present study linked the Vietnam Era Twin Registry with the Department of Veterans Affairs VistA patient care clinical database. Participants (n = 2,370, 59.6% monozygotic twins and 40.4% dizygotic twins) had a median of seven (interquartile range: 3-14) plasma sodium determinations between October 1999 and March 2017. Heritability of the mean plasma sodium concentration among all twins was 0.41 (95% confidence interval: 0.35-0.46) and 0.49 (95% confidence interval: 0.43-0.54) after exclusion of 514 twins with only a single plasma sodium determination. Heritability among Caucasian (n = 1,958) and African-American (n = 268) twins was 0.41 (95% confidence interval: 0.34-0.47) and 0.36 (95% confidence interval: 0.17-0.52), respectively. Exclusion of data from twins who had been prescribed medications known to impact systemic water balance had no effect. The ability of the present study to newly detect substantial heritability across multiple racial groups was potentially a function of the cohort size and relatedness, exclusion of sodium determinations confounded by elevated plasma glucose and/or reduced glomerular filtration rate, transformation of plasma sodium for the independent osmotic effect of plasma glucose, and use of multiple laboratory determinations per individual over a period of years. Individual-level plasma sodium concentration exhibited longitudinal stability (i.e., individuality); the degree to which individual-level means differed from the population mean was substantial, irrespective of the number of determinations. In aggregate, these data establish the heritability of plasma sodium concentration in European ancestry and corroborate its individuality.

Emerging treatment patterns and checkpoint inhibitor (CPI) use among newly diagnosed Merkel cell carcinoma (MCC) patients in the United States veteran population.

139 Background: MCC is a rare and aggressive skin cancer with annual incidence of 2,500 in the U.S. Checkpoint inhibitors (CPIs) demonstrated durable disease response historically not seen with chemotherapy among MCC patients in clinical trials. Avelumab, a PD-L1 antibody, became the first and only approved treatment for metastatic MCC by the U.S. FDA in March 2017. This study evaluated emerging treatment patterns among MCC patients using the US Veterans Health Administration (VHA) database. Methods: This retrospective study identified newly-diagnosed MCC patients who initiated ≥1 systemic therapy from Oct. 2013 to Jan. 2018 and had continuous enrollment from ≥6 months pre-initial MCC diagnosis date until ≥2 months post-index date with follow-up until the earliest of death, disenrollment, or study end. The index date was defined as the start date of first-line (1L) systemic therapy. A subsequent line of therapy (2L) was defined by the earliest of new therapy addition, regimen switch, or a new/existing regimen after a &gt;60-day gap from the prior cycle end. Duration of 1L therapy was evaluated among patients treated with CPIs, National Cancer Comprehensive Network (NCCN)-recommended chemotherapy (recCTs), and other chemotherapy (oCTs). The median duration of therapy was estimated using the Kaplan Meier method. Results: Of the 120 MCC patients (72% pre-2017) with 1L systemic therapy, 17%, 45%, and 38% were treated with CPIs, recCTs and oCTs, respectively. More than 75% were white men aged ≥65 years with mean baseline Charlson comorbidity index scores ≥5. Carboplatin-etoposide (56%) and cisplatin-etoposide (26%) were the most commonly-used recCTs. The median duration of 1L therapy in patients treated with CPI, recCTs and oCTs was 300, 91, and 21 days, respectively. 2L therapy was initiated in 33% of all 1L patients. Conclusions: Among 1L MCC patients, CPIs treated patients appear to be on treatment longer than both recCTs and oCTs patients. These descriptive findings provide important insights into the emerging real-world treatment patterns amongst MCC patients in the VHA population.

No significant difference in clinically relevant findings between Pillcam® SB3 and Pillcam® SB2 capsules in a United States veteran population.

BACKGROUNDCapsule endoscopy (CE) allows for a non-invasive small bowel evaluation for a wide range of gastrointestinal (GI) symptoms and diseases. Capsule technology has been rapidly advancing over recent years, often improving image frequency and quality. The Pillcam® SB3 (SB3) capsule is one such technology that offers an adaptive frame rate advantage over the previous versions of the capsule the Pillcam® SB2 (SB2). Some have proposed that this improvement in capsule technology may lead to increased diagnostic yields; however, real world clinical data is currently lacking.AIMTo evaluate the clinically relevant findings of SB3 and SB2 capsules in a population of United States veterans.METHODSA retrospective analysis of 260 consecutive CE studies was performed including 130 SB3 and 130 SB2 capsule studies. Recorded variables included: age, gender, type of capsule, body mass index, exam completion, inpatient status, opioid use, diabetes, quality of preparation, gastric transit time, small bowel transit time, indication, finding, and if the exam resulted in a change in clinical management. The primary outcome measured was the detection of clinically relevant findings between SB3 and SB2 capsules.RESULTSMean age of the study population was 67.1 ± 10.4 years and 94.2% of patients were male. Of these 28.1% were on opioid users. The most common indications for capsule procedure were occult GI bleeding (74.6%) and overt GI bleeding (14.6%). Rates of incomplete exam were similar between SB3 and SB2 groups (16.9% vs 9.2%, P = 0.066). The overall rate of clinically relevant finding was 48.9% in our study. No significant difference was observed in SB3 vs SB2 capsules for clinically relevant findings (46.2% vs 51.5%, P = 0.385) or change in clinical management (40.8% vs 50.0%, P = 0.135).CONCLUSIONOur study found no significant difference in clinically relevant findings between SB3 and SB2 capsules.

Abstract WP221: Relation Between Blood Pressure and Stroke Mortality in the United States Veteran Population

Introduction: Improved control of hypertension is largely credited for declines in stroke incidence and mortality. Previous studies have reported worse outcomes after ischemic stroke with lower blood pressures prior to the stroke. We investigated the relationship between pre-stroke systolic blood pressure (SBP) and mortality after ischemic stroke among U.S. Veterans. Methods: This longitudinal analysis assessed mortality risk after incident stroke in a national sample of Veterans Health Administration hospitalizations between 2002 and 2007. We included patients who had admission ICD-9 codes for ischemic stroke (433.x1, 434, and 436, excluding 434.x0) and ≥1 outpatient blood pressure measurements 1 to 18 months prior to stroke. We defined 6 categories of average baseline SBP: &lt;120, 120-129, 130-139, 140-149, 150-159, and ≥160 mm Hg. Multivariable Cox analyses were used to relate baseline SBP to all-cause and vascular mortality determined using the National Death Index. Results: There were 29,458 hospitalizations (mean age 67±12 years, 98% male) for incident stroke. During 4.1±3.3 years mean follow-up, there were 15,489 deaths (54%). There were 6,629 vascular deaths (23%). In a fully adjusted model, with high normal pre-stroke SBP (130-139) as the reference, risk of all-cause mortality was increased for patients with very low-to-normal SBP (&lt;120), normal SBP (120-129), and very high SBP (≥160) (Table 1A). The risk of vascular mortality increased with very low (&lt;120) and very high (≥160) SBP levels, but was not increased with normal SBP (120-129) (Table 1B). Conclusions: In U.S. Veterans hospitalized with first-ever stroke, very low and very high pre-stroke systolic blood pressure levels increased risk of all-cause and vascular mortality. Optimal SBP targets after stroke, particularly in patients with low pre-stroke SBP, merit further investigation.

Diagnostic Yields of Pillcam® SB3 versus Pillcam® SB2 Capsules in a United States Veteran Population

Introduction: Capsule endoscopy offers a non-invasive form of small bowel evaluation for a variety of gastrointestinal symptoms and diseases. Capsule technology has been rapidly advancing over recent years, often improving image frequency and quality. The Pillcam® SB3 capsule is one such technology that offers an adaptive frame rate advantage over previous capsule versions. Some have proposed that this improvement in capsule technology may lead to increased diagnostic yields; however, real world clinical data is currently lacking. Methods: Retrospective analysis of 260 consecutive (130 Pillcam® SB3 and 130 Pillcam® SB2) capsule endoscopy studies at our Veterans Affairs Medical Center was performed. Recorded variables included: Age, gender, type of capsule, body mass index (BMI), exam completion, inpatient status, quality of prep, gastric transit time (GTT), small bowel transit time (SBTT), indication, finding, and if the exam resulted in a change in clinical management. Significance (p<0.05) was assessed using t-test for normally distributed continuous variables and chi-square or Fisher's exact test as appropriate for categorical variables. Results: Group characteristics for Pillcam® SB3 and Pillcam® SB2 capsules are presented in Table 1 and included: Age (68.3 ± 11.1 vs 65.9 ± 9.5, p=0.061), male gender (93.8% vs 94.6%, p=0.790), BMI (30.1 ± 6.1 vs 30.5 ± 6.4 p=0.618), incomplete exam (16.9% vs 9.2% p=0.066), inpatient status (14.6% vs 10% p=0.257), GTT (37.7 ± 40.4 mins vs 41.4 ± 53.4 mins, p= 0.539), SBTT (223.1 ± 81.4 mins vs 208.8 ± 87.3 mins, p=0.033), and inadequate preparation (11.5% vs 13.8%, p=0.576). Procedure indications included: Occult GIB (70.8% vs 78.5%, p=0.154), overt GIB (18.5% vs 10.8% p=0.079), tumor/polyp evaluation (3.2% vs 3.8%, p=0.999), IBD (1.5% vs 3.8%, p=0.447), other (6.2% vs 3.1%, p=0.237). Capsule findings are presented in Table 2. No significant difference was observed in Pillcam® SB3 vs Pillcam® SB2 capsules for clinically relevant findings (46.2% vs 51.5%, p=0.385) or for changes in clinical management (40.8% vs 50.0%, p=0.135). Conclusion: Our study found no significant difference in clinically relevant findings between Pillcam® SB3 and Pillcam® SB2 capsules. Additionally, no significant change in clinical management was observed. Further prospective research is needed to determine if this capsule improvement enhances clinical findings or impacts clinical management.1156_A Figure 1. Baseline Demographics1156_B Figure 2. Indications and Findings of Pillcam® SB3 vs Pillcam® SB2 Capsule Studies

Tu1500 - Risk of Hepatocellular Cancer Recurrence in HCV Patients Treated with Direct-Acting Antiviral Agents in a United States Veteran Population

Tu1500 - Risk of Hepatocellular Cancer Recurrence in HCV Patients Treated with Direct-Acting Antiviral Agents in a United States Veteran Population

The epidemiology of hospital-acquired urinary tract-related bloodstream infection in veterans

Hospital-acquired urinary tract-related bloodstream infections are rare but often lethal. Recent epidemiology of this condition among the United States veteran population is poorly described. We conducted a retrospective review of hospital-acquired urinary tract-related bloodstream infections of adult inpatients admitted to 4 Veterans Affairs hospitals over 15 years. Electronic medical records were used to obtain clinical, demographic, and microbiologic information. Descriptive statistical analyses were conducted using chi-square tests of association. Test for trend was performed by genus of organism and for case fatality rate over time. While the most commonly isolated organisms were Staphylococcus spp. (36.5%), the incidence of infections caused by Escherichia and Klebsiella increased over time (P = .02 and P = .03, respectively). The overall in-hospital case fatality rate was 24.2% in 499 patients. The case fatality rate was 25.8% for patients with Staphylococcus infections and 20.7% for patients with enterococcal infections. Hospital-acquired urinary tract-related bloodstream infection is commonly due to Staphylococcus spp. and is related to the high fatality among United States veterans. Focused infection control efforts could decrease the incidence of this fatal infection.

Benzodiazepine Use in Older Adults in the United States, Ontario, and Australia from 2010 to 2016.

To detail annual trends in benzodiazepine incidence and prevalence in older adults between 2010 and 2016 in three countries. Observational multicountry cohort study with harmonized study protocol. The United States (veteran population); Ontario, Canada; and Australia. All people aged 65 and older (8,270,000 people). Annual incidence and prevalence of benzodiazepine use stratified according to age group (65-74, 75-84, ≥85) and sex. We performed multiple regression analyses to assess whether rates of incident and prevalent use changed significantly over time. Over the study period, we observed a significant decrease in incident benzodiazepine use in the United States (2.6% to 1.7%) and Ontario (6.0% to 4.4%) but not Australia (7.0% to 6.7%). We found significant declines in prevalent use in all countries (United States: 9.2% to 7.3%; Ontario: 18.2% to 13.4%; Australia: 20.2% to 16.8%). Although incidence and prevalence increased with age in Ontario and Australia, they decreased with age in the United States. Incidence and prevalence were higher in women in all countries. Consistent with other international studies, there have been small but significant reductions in the incidence and prevalence of benzodiazepine use in older adults in all three countries, with the exception of incidence in Australia, although use remains inappropriately high-particularly in those aged 85 and older-which warrants further attention from clinicians and policy-makers.