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Dive into the research topics where Adriana Valderrama is active.

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Featured researches published by Adriana Valderrama.


Hepatology | 2017

Identifying barriers to hepatocellular carcinoma surveillance in a national sample of patients with cirrhosis

David S. Goldberg; Tamar H. Taddei; Marina Serper; Rajni Mehta; Eric Dieperink; Ayse Aytaman; Michelle Baytarian; Rena K. Fox; Kristel K. Hunt; Marcos Pedrosa; Christine Pocha; Adriana Valderrama; David E. Kaplan

Hepatocellular carcinoma (HCC) is a leading cause of morbidity and mortality in cirrhosis patients. This provides an opportunity to target the highest‐risk population, yet surveillance rates in the United States and Europe range from 10% to 40%. The goal of this study was to identify barriers to HCC surveillance, using data from the Veterans Health Administration, the largest provider of liver‐related health care in the United States. We included all patients 75 years of age or younger who were diagnosed with cirrhosis from January 1, 2008, until December 31, 2010. The primary outcome was a continuous measure of the percentage of time up‐to‐date with HCC surveillance (PTUDS) based on abdominal ultrasound (secondary outcomes included computed tomography and magnetic resonance imaging). Among 26,577 patients with cirrhosis (median follow‐up = 4.7 years), the mean PTUDS was 17.8 ± 21.5% (ultrasounds) and 23.3 ± 24.1% when any liver imaging modality was included. The strongest predictor of increased PTUDS was the number of visits to a specialist (gastroenterologist/hepatologist and/or infectious diseases) in the first year after cirrhosis diagnosis; the association between visits to a primary care physician and increasing surveillance was very small. Increasing distance to the closest Veterans Administration center was associated with decreased PTUDS. There was an inverse association between ultrasound lead time (difference between the date an ultrasound was ordered and requested exam date) and the odds of it being performed: odds ratio = 0.77, 95% confidence interval 0.72‐0.82 when ordered > 180 days ahead of time; odds ratio = 0.90, 95% confidence interval 0.85‐0.94 if lead time 91‐180 days. Conclusions: The responsibility for suboptimal surveillance rests with patients, providers, and the overall health care system; several measures can be implemented to potentially increase HCC surveillance, including increasing patient–specialist visits and minimizing appointment lead time. (Hepatology 2017;65:864‐874).


Clinical Gastroenterology and Hepatology | 2015

Development and Performance of an Algorithm to Estimate the Child-Turcotte-Pugh Score From a National Electronic Healthcare Database.

David E. Kaplan; Feng Dai; Ayse Aytaman; Michelle Baytarian; Rena K. Fox; Kristel K. Hunt; Astrid Knott; Marcos Pedrosa; Christine Pocha; Rajni Mehta; Mona Duggal; Melissa Skanderson; Adriana Valderrama; Tamar H. Taddei

BACKGROUND & METHODS The Child-Turcotte-Pugh (CTP) score is a widely used and validated predictor of long-term survival in cirrhosis. The CTP score is a composite of 5 subscores, 3 based on objective clinical laboratory values and 2 subjective variables quantifying the severity of ascites and hepatic encephalopathy. To date, no system to quantify CTP score from administrative databases has been validated. The Veterans Outcomes and Costs Associated with Liver Disease study is a multicenter collaborative study to evaluate the outcomes and costs of hepatocellular carcinoma in the U.S. Veterans Health Administration. We developed and validated an algorithm to calculate electronic CTP (eCTP) scores by using data from the Veterans Health Administration Corporate Data Warehouse. METHODS Multiple algorithms for determining each CTP subscore from International Classification of Diseases version 9, Common Procedural Terminology, pharmacy, and laboratory data were devised and tested in 2 patient cohorts. For each cohort, 6 site investigators (Boston, Bronx, Brooklyn, Philadelphia, Minneapolis, and West Haven VA Medical Centers) were provided cases from which to determine validity of diagnosis, laboratory data, and clinical assessment of ascites and encephalopathy. The optimal algorithm (designated eCTP) was then applied to 30,840 cirrhotic patients alive in the first quarter of 2008 for whom 5-year overall and transplant-free survival data were available. The ability of the eCTP score and other disease severity scores (Charlson-Deyo index, Veterans Aging Cohort Study index, Model for End-Stage Liver Disease score, and Cirrhosis Comorbidity) to predict survival was then assessed by Cox proportional hazards regression. RESULTS Spearman correlations for administrative and investigator validated laboratory data in the HCC and cirrhotic cohorts, respectively, were 0.85 and 0.92 for bilirubin, 0.92 and 0.87 for albumin, and 0.84 and 0.86 for international normalized ratio. In the HCC cohort, the overall eCTP score matched 96% of patients to within 1 point of the chart-validated CTP score (Spearman correlation, 0.81). In the cirrhosis cohort, 98% were matched to within 1 point of their actual CTP score (Spearman, 0.85). When applied to a cohort of 30,840 patients with cirrhosis, each unit change in eCTP was associated with 39% increase in the relative risk of death or transplantation. The Harrell C statistic for the eCTP (0.678) was numerically higher than those for other disease severity indices for predicting 5-year transplant-free survival. Adding other predictive models to the eCTP resulted in minimal differences in its predictive performance. CONCLUSION We developed and validated an algorithm to extrapolate an eCTP score from data in a large administrative database with excellent correlation to actual CTP score on chart review. When applied to an administrative database, this algorithm is a highly useful predictor of survival when compared with multiple other published liver disease severity indices.


Journal of Clinical Gastroenterology | 2016

Hepatocellular Carcinoma Surveillance Among Cirrhotic Patients With Commercial Health Insurance.

David S. Goldberg; Adriana Valderrama; Rajesh Kamalakar; Sujit S. Sansgiry; Svetlana Babajanyan; James D. Lewis

Goals: To evaluate hepatocellular carcinoma (HCC) surveillance rates among commercially insured patients, and evaluate factors associated with compliance with surveillance recommendations. Background: Most HCC occurs in patients with cirrhosis. American Association for the Study of Liver Diseases and European Association for the Study of the Liver guidelines each recommend biannual HCC surveillance for cirrhotic patients to diagnose HCC at an early, curable stage. However, compliance with these guidelines in commercially insured patients is unknown. Study: We used the Truven Health Analytics databases from 2006 to 2010, using January 1, 2006 as the anchor date for evaluating outcomes. The primary outcome was continuous surveillance measure, defined as the proportion of time “up-to-date” with surveillance (PTUDS), with the 6-month interval immediately following each ultrasound categorized as “up-to-date.” Results: During a median follow-up of 22.9 (interquartile range, 16.3 to 33.9) months among 8916 cirrhotic patients, the mean PTUDS was 0.34 (SD, 0.29), and the median was 0.31 (interquartile range, 0.03 to 0.52). These values increased only modestly with inclusion of serum alpha-fetoprotein testing, contrast-enhanced abdominal computed tomographic scans or magnetic resonance imagings, and/or extension of up-to-date time to 12 months. Being diagnosed by a nongastroenterology provider and increasing age were significantly associated with decreased HCC surveillance (P<0.05), whereas a history of a hepatic decompensation event, presence of any component of the metabolic syndrome, and diagnosis of hepatitis B or hepatitis C were significantly associated with increased surveillance (P<0.05). However, even among patients with the most favorable characteristics, surveillance rates remained low. Conclusions: HCC surveillance rates in commercially insured at-risk patients remain poor despite formalized guidelines, highlighting the need to develop interventions to improve surveillance rates.


Journal of Viral Hepatitis | 2015

Hepatocellular carcinoma surveillance rates in commercially insured patients with noncirrhotic chronic hepatitis B

David S. Goldberg; Adriana Valderrama; Rajesh Kamalakar; Sujit S. Sansgiry; Svetlana Babajanyan; James D. Lewis

American association for the study of liver diseases (AASLD) and European Association for the Study of the Liver (EASL) guidelines recommend biannual hepatocellular carcinoma (HCC) screening for noncirrhotic patients with chronic hepatitis B infection (HBV), yet there are no data estimating surveillance rates or factors associated with surveillance. We performed a retrospective cohort study of US patients using the Truven Health Analytics databases from 2006 to 2010 and identified patients with noncirrhotic chronic HBV. Surveillance patterns were characterized using categorical and continuous outcomes, with the continuous measure of the proportion of time ‘up to date’ with surveillance (PUTDS), with the 6‐month interval following each ultrasound categorized as ‘up to date’. During a median follow‐up of 26.0 (IQR: 16.2–40.0) months among 4576 noncirrhotic patients with chronic HBV (median age: 44 years, IQR: 36–52), only 306 (6.7%) had complete surveillance (one ultrasound every 6‐month interval), 2727 (59.6%) incomplete (≥1 ultrasound) and 1543 (33.7%) none. The mean PUTDS was 0.34 ± 0.29, and the median was 0.32 (IQR: 0.03–0.52). In multinomial logistic regression models, patients diagnosed by a nongastroenterologist were significantly less likely to have complete surveillance (P < 0.001), as were those coinfected with HBV/HIV (P < 0.001). In linear regression models, nongastroenterologist provider, health insurance subtype, HBV/HIV coinfection, rural status and metabolic syndrome were independently associated with decreased surveillance. Patients with HIV had an absolute decrease in the PUTDS of 0.24, while patients in less populated rural areas had an absolute decrease of 0.10. HCC surveillance rates in noncirrhotic patients with chronic HBV in the United States are poor and lower than reported rates of HCC surveillance in cirrhotic patients.


Current Medical Research and Opinion | 2012

Modelling survival in hepatocellular carcinoma

Noemi Muszbek; Noémi Kreif; Adriana Valderrama; Agnes Benedict; Jack Ishak; Paul Ross

Abstract Objectives: To identify the pattern of the risk of death over long-term in unresectable hepatocellular carcinoma by determining the appropriate distribution to extrapolate overall survival and to assess the role of the Weibull distribution as the standard survival model in oncology. Research design and methods: To select the appropriate distribution, three types of data sources have been analysed. Patient level data from two randomized controlled trials and published Kaplan–Meier curves from a systematic literature review provided short term follow-up data. They were supplemented with patient level data, with long-term follow-up from the Cancer Institute New South Wales, Australia. Published Kaplan–Meier curves were read in and a time-to-event dataset was created. Distributions were fitted to the data from the different sources separately. Their fit was assessed visually and compared using statistical criteria based on log-likelihood, the Akaike information criterion (AIC), and the Bayesian information criterion (BIC). Results: Based on both published and patient-level, and both short- and long-term follow-up data, the Weibull distribution, used very often in cost-effectiveness models in oncology, does not seem to offer a good fit in hepatocellular carcinoma among the different survival models. The best fitting distribution appears to be the lognormal, with loglogistic as the second-best fitting function. Results were consistent between the different sources of data. Conclusions: In unresectable hepatocellular carcinoma, the Weibull model, which is often treated at the gold standard, does not appear to be appropriate based on different sources of data (two clinical trials, a retrospective database and published Kaplan–Meier curves). Lognormal distribution seems to be the most appropriate distribution for extrapolating overall survival.


Clinical Gastroenterology and Hepatology | 2018

Healthcare Costs Related to Treatment of Hepatocellular Carcinoma Among Veterans With Cirrhosis in the United States

David E. Kaplan; Michael K. Chapko; Rajni Mehta; Feng Dai; Melissa Skanderson; Ayse Aytaman; Michelle Baytarian; Kathryn D’Addeo; Rena K. Fox; Kristel K. Hunt; Christine Pocha; Adriana Valderrama; Tamar H. Taddei

BACKGROUND & AIMS: It is important to quantify medical costs associated with hepatocellular carcinoma (HCC), the incidence of which is rapidly increasing in the United States, for development of rational healthcare policies related to liver cancer surveillance and treatment of chronic liver disease. We aimed to comprehensively quantify healthcare costs for HCC among patients with cirrhosis in an integrated health system and develop a model for predicting costs that is based on clinically relevant variables. METHODS: Three years subsequent to liver cancer diagnosis, costs accrued by patients included in the Veterans Outcome and Cost Associated with Liver disease cohort were compiled by using the Department of Veterans Affairs Corporate Data Warehouse. The cohort includes all patients with HCC diagnosed in 2008–2010 within the VA with 100% chart confirmation as well as chart abstraction of tumor and clinical characteristics. Cancer cases were matched 1:4 with non‐cancer cirrhosis controls on the basis of severity of liver disease, age, and comorbidities to estimate background cirrhosis‐related costs. Univariable and multivariable generalized linear models were developed and used to predict cancer‐related overall cost. RESULTS: Our analysis included 3188 cases of HCC and 12,722 controls. The mean 3‐year total cost of care in HCC patients was


JCO Clinical Cancer Informatics | 2018

An Approach to Identify Delivery of Palliative Radiation Therapy Using Health Care Claims Data: A Proof-of-Concept Application of a Visual Analytics Tool

Eberechukwu Onukwugha; Jinani Jayasekera; James F. Gardner; Sana Malik; C. Daniel Mullins; Arif Hussain; Jay P. Ciezki; C.A. Reddy; B. Seal; Adriana Valderrama; Young Kwok

154,688 (standard error,


Value in Health | 2017

Economic Evaluation of Treating Skeletal-Related Events among Prostate Cancer Patients

Yue Zhong; Adriana Valderrama; Jianying Yao; P. Donga; Pinar Bilir; Peter J. Neumann

150,953–


Leukemia & Lymphoma | 2016

Indirect costs and workplace productivity loss associated with non-Hodgkin lymphoma

Justin Yu; Ryan N. Hansen; Adriana Valderrama; Josh J. Carlson

158,422) compared with


Clinical Therapeutics | 2016

Opioid Use Among Metastatic Prostate Cancer Patients With Skeletal-related Events

Avin Yaldo; L. Wen; Augustina Ogbonnaya; Adriana Valderrama; Jonathan K Kish; Michael Eaddy; Charles Kreilick; Krishna Tangirala; Katarzyna Shields

69,010 (standard error,

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David E. Kaplan

University of Pennsylvania

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Ayse Aytaman

United States Department of Veterans Affairs

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B. Seal

Bayer HealthCare Pharmaceuticals

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Kristel K. Hunt

Icahn School of Medicine at Mount Sinai

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Rena K. Fox

University of California

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Christine Pocha

University of South Dakota

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L. Wen

Bayer HealthCare Pharmaceuticals

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Marcos Pedrosa

VA Boston Healthcare System

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