Nathanael R. Fillmore
Topics / Retrospective Cohort Study
Topic

Retrospective Cohort Study

Fillmore has extensively utilized retrospective cohort studies to identify prognostic biomarkers and evaluate real-world treatment outcomes across oncology, neurology, and infectious disease. His work has established the independent impact of frailty and multimorbidity on survival in patients with hematologic and lung cancers, while also identifying associations between systemic inflammation and dementia risk. Additionally, he has employed large-scale veteran datasets to quantify racial and socioeconomic disparities in cancer care and to assess the effectiveness of vaccinations and therapeutics during the COVID-19 pandemic.

U.S. Veterans and VA Data 57 Real World Evidence 26 Overall Survival 24 Electronic Health Records 23 Patient Outcomes 23 Cox Proportional Hazards Model 21 Survival Analysis 19 Risk Factors 15 Cancer Patients 15 COVID-19 14 Frailty 12 Race and Ethnicity 11

Publications (61)

2026

A retrospective cohort study using the Veterans Affairs Cancer Registry database: Increased hazard of Parkinson's disease in United States Veterans with melanoma.

Linden B. Huhmann†, Jonathan C. Hwang†, David Perez, Daniel Y. Kim, Kaelyn Nannini, Nhan V. Do, John M. Gaziano, Mary T. Brophy, Lee E. Wheless, Nathanael R. Fillmore‡, Rebecca I. Hartman‡† Equal first authorship · ‡ Equal senior authorship

Journal of the American Academy of Dermatology
Cutaneous Melanoma Parkinson's Disease Retrospective Cohort Study U.S. Veterans and VA Data VA Cancer Registry
2026

Association of Frailty With Transfusions, Hospitalizations, and Survival in Patients With Myelodysplastic Syndrome Initiating Hypomethylating Agents.

Anahid Hamparsumian†, Jennifer La†, Mayuri Dharne, Gary Gilbert, Mary T. Brophy, Nhan V. Do, Dae Hyun Kim, Jane A. Driver, Nathanael R. Fillmore‡, Clark DuMontier‡† Equal first authorship · ‡ Equal senior authorship

EJHaem7(4), e70352
U.S. Veterans and VA Data Retrospective Cohort Study Frailty Overall Survival Hospitalization Metrics
2026

Frailty and survival outcomes in veterans with invasive cutaneous melanoma: A Veterans Affairs Cancer Registry retrospective cohort study.

Linden B. Huhmann†, Jonathan C. Hwang†, Daniel Y. Kim, Kaelyn Nannini, Nhan V. Do, John M. Gaziano, Lee E. Wheless, Nathanael R. Fillmore‡, Rebecca I. Hartman‡† Equal first authorship · ‡ Equal senior authorship

Journal of the American Academy of Dermatology95(1), 240-243
U.S. Veterans and VA Data Retrospective Cohort Study Cancer-Associated Thrombosis Cutaneous Melanoma Overall Survival
2026

Parkinson's disease and risk of melanoma in United States veterans: A Veterans Affairs Cancer Registry retrospective cohort study.

Jonathan C. Hwang†, Linden B. Huhmann†, David Perez, Daniel Y. Kim, Kaelyn Nannini, Nhan V. Do, John M. Gaziano, Mary T. Brophy, Lee E. Wheless, Nathanael R. Fillmore‡, Rebecca I. Hartman‡† Equal first authorship · ‡ Equal senior authorship

Journal of the American Academy of Dermatology94(6), 1811-1814
U.S. Veterans and VA Data Retrospective Cohort Study VA Cancer Registry Parkinson's Disease Cutaneous Melanoma
2026

Sodium-Glucose Cotransporter 2 Inhibitors and Dementia Risk in Patients With Psychiatric Disorders.

David T. Liebers†, Tianshe He†, Rebecca A. Betensky, Chunlei Zheng, Kaitlin N. Swinnerton, Sean Jacobson, Linden Huhmann, Mary T. Brophy, Nhan V. Do, Paola Gilsanz, Ricardo S. Osorio, Nunzio Pomara, Antonio Convit, Donald C. Goff, Dan V. Iosifescu, Nathanael R. Fillmore, Jaime Ramos-Cejudo† Equal first authorship

JAMA Network Open9(6), e2619985
U.S. Veterans and VA Data Retrospective Cohort Study Electronic Health Records Alzheimer Disease and Dementia SGLT2 Inhibitors
2026

Risk factors for the development of acral melanoma: A multi-institutional, retrospective cohort study.

Charles Lu†, Olivia Burke†, Christopher J. Thang, Sara Khattab, Nga Nguyen, Emma Beagles, Crystal Chang, Suzanne Xu, Jonathan C. Hwang, Linden Huhmann, Nicholas Starink, Martin A. Weinstock, Maryam M. Asgari, Marc S. Hurlbert, John M. Gaziano, Nathanael R. Fillmore, Theodore C. Feldman, Rebecca I. Hartman, Yevgeniy R. Semenov† Equal first authorship

JAAD international28, 38-46
Acral Melanoma Race and Ethnicity Risk Factors Retrospective Cohort Study Logistic Regression
2026

Neutrophil inflammation metrics are associated with the risk of future dementia in large data from NYU Langone Hospitals and the Veterans Health Administration.

Tianshe He, Rebecca A. Betensky, Ricardo S. Osorio, Kaitlin Swinnerton, Chunlei Zheng, Tovia Jacobs, Alok Vedvyas, Karyn Marsh, Joshua Chodosh, Ula Y. Hwang, Natalia Sifnugel, Omonigho M. Bubu, Thomas Wisniewski, Mary Brophy, Nhan V. Do, Nathanael R. Fillmore‡, Jaime Ramos-Cejudo‡‡ Equal senior authorship

Alzheimer's & Dementia22(4), e71335
U.S. Veterans and VA Data Retrospective Cohort Study Electronic Health Records Alzheimer Disease and Dementia Risk Factors
2026

Docetaxel Rechallenge vs Cabazitaxel in Patients With Metastatic Castration-Resistant Prostate Cancer.

Pedro C. Barata†, June K. Corrigan†, Jennifer La, John M. Culnan, Elliot Akama-Garren, Karlynn N. Dulberger, Clark Dumontier, Jason Hansen, John R. Bihn, Rhonda L. Bitting, Mary T. Brophy, Heather H. Cheng, Matthew R. Cooperberg, Nhan V. Do, Tanya Dorff, Antonio Tito Fojo, J. Michael Gaziano, Sergey D. Goryachev, Susan Halabi, Richard L. Hauger, David M. Nanus, Timothy R. Rebbeck, Chong-Xian Pan, Martin W. Schoen, Kaitlin N. Swinnerton, Kenute Myrie, Rachel B. Ramoni, Nathanael R. Fillmore, Channing J. Paller‡, Matthew B. Rettig‡† Equal first authorship · ‡ Equal senior authorship

JAMA Network Open9(1), e2551231
U.S. Veterans and VA Data Retrospective Cohort Study Metastatic Castration-Resistant Prostate Cancer Prostate Cancer Comparative Effectiveness
2026

Magnetic Resonance Imaging or Confirmatory Biopsy for Patients With Prostate Cancer Receiving Active Surveillance.

Matthew R. Cooperberg†, John R. Bihn†, John M. Culnan, Jennifer La, Sergey D. Goryachev, Daniel C. R. Chen, Oleg Soloviev, Grace Lee, June K. Corrigan, Kaitlin N. Swinnerton, Nicholas G. Nickols, Karlynn N. Dulberger, Pedro Barata, Rhonda L. Bitting, Mary T. Brophy, Heather H. Cheng, Hoedt Amanda De, Nhan V. Do, Stephen J. Freedland, Isla P. Garraway, J. Michael Gaziano, Susan Halabi, Richard L. Hauger, Stacy Loeb, David M. Nanus, Timothy R. Rebbeck, Matthew B. Rettig, Chong-Xian Pan, Kenute Myrie, Rachel B. Ramoni, Nathanael R. Fillmore‡, Channing J. Paller‡† Equal first authorship · ‡ Equal senior authorship

JAMA Oncology12(1), 111-113
U.S. Veterans and VA Data Retrospective Cohort Study Electronic Health Records Prostate Cancer Active Surveillance
2025

Potentially Inappropriate Medications, Frailty, and Outcomes in Patients With Cancer Managed in a National Health Care System.

Jennifer La, Tammy Hshieh, Anahid Hamparsumian, Robert Zwolinski, Jameson Wood, Mayuri Dharne, J. Michael Gaziano, Mary T. Brophy, Nhan V. Do, Nikhil C. Munshi, Jane A. Driver, Gregory A. Abel, Nathanael R. Fillmore‡, Clark DuMontier‡‡ Equal senior authorship

Journal of the National Comprehensive Cancer Network23(9), 363-370
U.S. Veterans and VA Data Retrospective Cohort Study Electronic Health Records Frailty Overall Survival
2025

Multimorbidity and Its Impact in Older U.S. Veterans Newly Treated for Advanced Non-Small Cell Lung Cancer.

Joseph R. Larsen†, Chunlei Zheng†, Jennifer La, Julie Tsu-Yu Wu, Michael Kelley, J. Michael Gaziano, Mary Brophy, Nhan V. Do, Dae H. Kim, Jane A. Driver, Clark DuMontier‡, Nathanael R. Fillmore‡† Equal first authorship · ‡ Equal senior authorship

Annals of the American Thoracic Society22(4), 598-608
U.S. Veterans and VA Data Retrospective Cohort Study Lung Cancer Overall Survival Geriatric Oncology
2025

Leveraging near-real-time patient and population data to incorporate fluctuating risk of severe COVID-19: development and prospective validation of a personalised risk prediction tool.

Kaitlin Swinnerton†, Nathanael R. Fillmore†, Austin Vo, Jennifer La, Danne Elbers, Mary Brophy, Nhan V. Do, Paul A. Monach‡, Westyn Branch-Elliman‡† Equal first authorship · ‡ Equal senior authorship

eClinicalMedicine81, 103114
U.S. Veterans and VA Data Retrospective Cohort Study COVID-19 Severe COVID-19 Predictive Modeling
2025

External validation of a novel cancer-associated venous thromboembolism risk assessment score in a safety-net hospital.

Karlynn N. Dulberger†, Jennifer La†, Ang Li†, Saran Lotfollahzadeh, Asha Jose, Nhan V. Do, Mary T. Brophy, J. Michael Gaziano, Katya Ravid, Vipul C. Chitalia, Nathanael R. Fillmore† Equal first authorship

Research and Practice in Thrombosis and Haemostasis9(1), 102650
Cancer-Associated Thrombosis External Validation Electronic Health Records Retrospective Cohort Study Cancer Patients
2024

Thrombosis risk prediction in lymphoma patients: A multi-institutional, retrospective model development and validation study.

Shengling Ma†, Jennifer La†, Kaitlin N. Swinnerton, Danielle Guffey, Raka Bandyo, Las Pozas Giordana De, Katy Hanzelka, Xiangjun Xiao, Cristhiam M. Rojas-Hernandez, Christopher I. Amos, Vipul Chitalia, Katya Ravid, Kelly W. Merriman, Christopher R. Flowers, Nathanael Fillmore‡, Ang Li‡† Equal first authorship · ‡ Equal senior authorship

American Journal of Hematology99(7), 1230-1239
U.S. Veterans and VA Data Retrospective Cohort Study Cancer-Associated Thrombosis Lymphoma Predictive Modeling
2024

Antidepressant exposure and long-term dementia risk in a nationwide retrospective study on US veterans with midlife major depressive disorder.

Jaime Ramos-Cejudo†, June K. Corrigan†, Chunlei Zheng, Kaitlin N. Swinnerton, Sean R. Jacobson, Jennifer La, Rebecca A. Betensky, Ricardo S. Osorio, Sharon Madanes, Nunzio Pomara, Dan Iosifescu, Mary Brophy, Nhan V. Do‡, Nathanael R. Fillmore‡† Equal first authorship · ‡ Equal senior authorship

Alzheimer's & Dementia20(6), 4106-4114
U.S. Veterans and VA Data Retrospective Cohort Study Alzheimer Disease and Dementia Major Depressive Disorder Antidepressant Therapy
2024

Real-world effectiveness of immune checkpoint inhibitors and BRAF/MEK inhibitors among veteran patients with cutaneous melanoma.

Daniel Y. Kim, Susan M. Swetter, Linden Huhmann, Matthew P. Dizon, Jacqueline M. Ferguson, Thomas F. Osborne, Allyson C. Spence, Amina Ziad, Nathanael Fillmore‡, Rebecca I. Hartman‡‡ Equal senior authorship

Journal of the American Academy of Dermatology90(3), 620-623
U.S. Veterans and VA Data Retrospective Cohort Study Cutaneous Melanoma Immune Checkpoint Inhibitors BRAF/MEK Inhibitors
2023

Prostate cancer patient stratification by molecular signatures in the Veterans Precision Oncology Data Commons.

Kyle M. Hernandez†, Aarti Venkat†, Danne C. Elbers†, John R. Bihn, Mary T. Brophy, Nhan V. Do, Jennifer La, Qiong Liu, Andrew Prokhorenkov, Noah Metoki-Shlubsky, Feng-Chi Sung, Channing J. Paller‡, Nathanael R. Fillmore‡, Robert L. Grossman‡† Equal first authorship · ‡ Equal senior authorship

Cold Spring Harbor Molecular Case Studies9(4)
U.S. Veterans and VA Data Retrospective Cohort Study Prostate Cancer Metastatic Castration-Resistant Prostate Cancer Precision Oncology
2023

More intensive therapy as more effective treatment for frail patients with multiple myeloma [corrected].

Clark DuMontier†, Jennifer La†, John Bihn, June Corrigan, Cenk Yildirim, Mayuri Dharne, Hamza Hassan, Sarvari Yellapragada, Gregory A. Abel, J. Michael Gaziano, Nhan V. Do, Mary Brophy, Dae H. Kim, Nikhil C. Munshi, Nathanael R. Fillmore‡, Jane A. Driver‡† Equal first authorship · ‡ Equal senior authorship

Blood Advances7(20), 6275-6284
U.S. Veterans and VA Data Retrospective Cohort Study Multiple Myeloma Frailty Overall Survival
2023

Prevalence of Central Venous Stenosis among Black and White ESKD Patients with Dysfunctional Dialysis Access.

Nkiruka Arinze, Jonathan D. Ravid, Kristina Yamkovoy, Najia Idrees, Mathew Diamond, Rohit Pillai, Tyler Ryan, Saran Lotfollahzadeh, Janice Weinberg, Nathanael R. Fillmore, Alik Farber, Rajendran Vilvendhan, Jean Francis, Vipul Chitalia

Journal of Health Disparities Research and Practice16(3), 71-89
Retrospective Cohort Study End-Stage Kidney Disease Central Venous Stenosis Fistulography Race and Ethnicity
2023

Derivation and Validation of a Clinical Risk Assessment Model for Cancer-Associated Thrombosis in Two Unique US Health Care Systems.

Ang Li†, Jennifer La†, Sarah B. May, Danielle Guffey, Costa Wilson L. da, Christopher I. Amos, Raka Bandyo, Emily M. Milner, Karen M. Kurian, Daniel C. R. Chen, Nhan V. Do, Carolina Granada, Nimrah Riaz, Mary T. Brophy, Vipul Chitalia, J. Michael Gaziano, David A. Garcia, Marc Carrier, Christopher R. Flowers, Neil A. Zakai‡, Nathanael R. Fillmore‡† Equal first authorship · ‡ Equal senior authorship

Journal of Clinical Oncology41(16), 2926-2938
Cancer-Associated Thrombosis Predictive Modeling Retrospective Cohort Study External Validation U.S. Veterans and VA Data
2023

Epidemiology of Cancer-Associated Venous Thromboembolism in Patients With Solid and Hematologic Neoplasms in the Veterans Affairs Health Care System.

Kylee L. Martens†, Ang Li†, Jennifer La, Sarah B. May, Kaitlin N. Swinnerton, Hannah Tosi, Danne C. Elbers, Nhan V. Do, Mary T. Brophy, J. Michael Gaziano, Saran Lotfollahzadeh, Vipul Chitalia, Katya Ravid, Nathanael R. Fillmore† Equal first authorship

JAMA Network Open6(6), e2317945
U.S. Veterans and VA Data Retrospective Cohort Study Electronic Health Records Cancer-Associated Thrombosis Health Disparities
2023

Allostatic load and cardiovascular outcomes in males with prostate cancer.

Nickolas Stabellini, Jennifer Cullen, Marcio S. Bittencourt, Justin X. Moore, Lifen Cao, Neal L. Weintraub, Ryan A. Harris, Xiaoling Wang, Biplab Datta, Steven S. Coughlin, Jorge Garcia, John Shanahan, Nelson Hamerschlak, Kristin Waite, Nathanael R. Fillmore, Martha Terris, Alberto J. Montero, Jill S. Barnholtz-Sloan‡, Avirup Guha‡‡ Equal senior authorship

JNCI Cancer Spectrum7(2)
Allostatic Load Cardiovascular Disease Major Adverse Cardiovascular Events Prostate Cancer Fine-Gray Models
2023

Coronavirus disease 2019 (COVID-19) hospitalization metrics that do not account for disease severity underestimate protection provided by severe acute respiratory coronavirus virus 2 (SARS-CoV-2) vaccination and boosting: A retrospective cohort study.

June K. Corrigan†, Jennifer La†, Nathanael R. Fillmore, Nhan V. Do, Mary Brophy, Shira Doron, Paul A. Monach‡, Westyn Branch-Elliman‡† Equal first authorship · ‡ Equal senior authorship

Infection Control and Hospital Epidemiology44(1), 149-151
U.S. Veterans and VA Data Retrospective Cohort Study Electronic Health Records COVID-19 Vaccine Effectiveness
2022

The COVID-19 hospitalization metric in the pre- and postvaccination eras as a measure of pandemic severity: A retrospective, nationwide cohort study.

Nathanael R. Fillmore†, Jennifer La†, Chunlei Zheng, Shira Doron, Nhan V. Do, Paul A. Monach‡, Westyn Branch-Elliman‡† Equal first authorship · ‡ Equal senior authorship

Infection Control and Hospital Epidemiology43(12), 1767-1772
U.S. Veterans and VA Data Retrospective Cohort Study COVID-19 Vaccine Effectiveness Hospitalization Metrics
2022

Potential long-term effect of tumor necrosis factor inhibitors on dementia risk: A propensity score matched retrospective cohort study in US veterans.

Chunlei Zheng†, Nathanael R. Fillmore†, Jaime Ramos-Cejudo, Mary Brophy, Ricardo Osorio, Mark E. Gurney, Wei Qiao Qiu, Rhoda Au, George Perry, Maureen Dubreuil, Shu G. Chen, Xin Qi, Pamela B. Davis, Nhan Do, Rong Xu† Equal first authorship

Alzheimer's & Dementia18(6), 1248-1259
U.S. Veterans and VA Data Retrospective Cohort Study TNF Inhibitors Alzheimer Disease and Dementia Propensity Score Matching
2022

Association of COVID-19 Vaccination With SARS-CoV-2 Infection in Patients With Cancer: A US Nationwide Veterans Affairs Study.

Julie Tsu-Yu Wu†, Jennifer La†, Westyn Branch-Elliman, Linden B. Huhmann, Summer S. Han, Giovanni Parmigiani, David P. Tuck, Mary T. Brophy, Nhan V. Do, Albert Y. Lin‡, Nikhil C. Munshi‡, Nathanael R. Fillmore‡† Equal first authorship · ‡ Equal senior authorship

JAMA Oncology8(2), 281-286
U.S. Veterans and VA Data Retrospective Cohort Study COVID-19 Vaccine Effectiveness Cancer Patients
2021

Defining Multimorbidity and Its Impact in Older United States Veterans Newly Treated for Multiple Myeloma.

Nathanael R. Fillmore†, Clark DuMontier†, Cenk Yildirim, Jennifer La, Mara M. Epstein, David Cheng, Diana Cirstea, Sarvari Yellapragada, Gregory A. Abel, J. Michael Gaziano, Nhan Do, Mary Brophy, Dae H. Kim, Nikhil C. Munshi, Jane A. Driver† Equal first authorship

Journal of the National Cancer Institute113(8), 1084-1093
U.S. Veterans and VA Data Retrospective Cohort Study Multiple Myeloma Overall Survival Geriatric Oncology
2021

Contemporary Analysis of Electronic Frailty Measurement in Older Adults with Multiple Myeloma Treated in the National US Veterans Affairs Healthcare System.

Clark DuMontier†, Nathanael R. Fillmore†, Cenk Yildirim, David Cheng, Jennifer La, Ariela R. Orkaby, Brian Charest, Diana Cirstea, Sarvari Yellapragada, John Michael Gaziano, Nhan Do, Mary T. Brophy, Dae H. Kim, Nikhil C. Munshi, Jane A. Driver† Equal first authorship

Cancers13(12)
U.S. Veterans and VA Data Retrospective Cohort Study Electronic Health Records Multiple Myeloma Frailty
2021

Updating and Validating the U.S. Veterans Affairs Frailty Index: Transitioning From ICD-9 to ICD-10.

David Cheng†, Clark DuMontier†, Cenk Yildirim, Brian Charest, Chelsea E. Hawley, Min Zhuo, Julie M. Paik, Enzo Yaksic, J. Michael Gaziano, Nhan Do, Mary Brophy, Kelly Cho, Dae H. Kim, Jane A. Driver, Nathanael R. Fillmore‡, Ariela R. Orkaby‡† Equal first authorship · ‡ Equal senior authorship

Journals of Gerontology: Series A76(7), 1318-1325
U.S. Veterans and VA Data Electronic Health Records Frailty Electronic Frailty Index ICD-10 Coding