Rod Walker, MS

Walker_Rod_L_205x293.jpg

“I feel fortunate to have the opportunity to provide biostatistical support across a wide range of KPWHRI collaborations that contribute to public health knowledge and improve health care for patients.”

Rod Walker, MS

Principal Collaborative Biostatistician, Kaiser Permanente Washington Health Research Institute

Rod.L.Walker@kp.org
206-287-2895

Biography

Rod Walker, MS, has developed a diverse research portfolio during his 15+ years as a biostatistician at KPWHRI. He has supported research collaborations across a wide range of topic areas including women's health, cancer, aging and geriatrics, physical activity and sedentary behavior, pharmacoepidemiology, opioids, traumatic brain injury, COVID-19, and mental health. Activities during his tenure have included serving as an analyst for the Statistical Coordinating Center for the National Cancer Institute's Breast Cancer Surveillance Consortium; evaluating health system initiatives aimed at reducing risks associated with chronic opioid therapy prescribing; and examining associations between various medication classes and outcomes such as pneumonia, fall-related injury, and dementia. He has also partnered with researchers in the Mental Health Research Network  to leverage electronic health record data for predicting risk of suicide attempt and suicide death. These efforts have expanded his knowledge in machine learning, risk prediction, health informatics, and the practical challenges of implementing predictive tools into clinical workflows.

Mr. Walker’s longest-running collaboration is with the Adult Changes in Thought (ACT) study, an ongoing longitudinal cohort study seeking to bolster knowledge of risk factors related to dementia, Alzheimer's disease, and healthy aging. As the ACT study and its related projects have grown, he has contributed to analyses examining how medication use, biomarkers, and other exposures relate to cognitive outcomes in older adults — and has extended this work to investigate associations with neuropathology among participants who provided brain donations. His tenure with ACT has afforded him the opportunity to participate in varied activities such as processing and analyzing physical activity and sedentary behavior data from actigraphy devices worn by study participants; supporting development of prediction models to identify unrecognized dementia by leveraging the unique data available through ACT; and exploring relationships between eye diseases and dementia in collaboration with the Eye ACT ancillary study. Mr. Walker currently serves as co-lead of the ACT Data Science and Informatics Core, helping guide data infrastructure development and coordinate data sharing activities. Continued collaboration with ACT investigators remains a highlight of his research career at KPWHRI, as the study provides rich opportunities to advance public health knowledge relevant to aging populations.

Research interests and experience

  • Biostatistics

    Survival and longitudinal data analysis; epidemiology; machine learning; two-phase sampling

  • Aging & Geriatrics

    Biostatistics; cognitive health and dementia; neuropathologic correlates of dementia; factors associated with healthy aging

  • Mental Health

    Biostatistics; suicide risk prediction; interventions for risk reduction; machine learning and health informatics

  • Medication Use & Patient Safety

    Biostatistics; pharmacoepidemiology; medication safety in older adults; opioids and chronic pain

  • Health Informatics

  • Women's Health

Recent publications

Walker RL, Shortreed SM, Ziebell RA, Johnson E, Boggs JM, Lynch FL, Daida YG, Ahmedani BK, Rossom R, Coleman KJ, Simon GE Evaluation of Electronic Health Record-Based Suicide Risk Prediction Models on Contemporary Data 2021 Aug;12(4):778-787. doi: 10.1055/s-0041-1733908. Epub 2021-08-18. PubMed

Dublin S, Walker RL, Floyd JS, Shortreed SM, Fuller S, Albertson-Junkans L, Harrington LB, Greenwood-Hickman MA, Green BB, Psaty BM Response to "ACE-2 downregulation and incidence of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection" 2021 Apr 20;34(4):427. doi: 10.1093/ajh/hpaa212. PubMed

Dublin S, Walker RL, Floyd JS, Shortreed SM, Fuller S, Albertson-Junkans L, Harrington LB, Greenwood-Hickman MA, Green BB, Psaty BM Renin-angiotensin-aldosterone system inhibitors and COVID-19 infection or hospitalization: a cohort study 2021 Apr 20;34(4):339-347. doi: 10.1093/ajh/hpaa168. PubMed

Walker RL, Greenwood-Hickman MA, Bellettiere J, LaCroix AZ, Wing D, Higgins M, Richmire K, Larson EB, Crane PK, Rosenberg DE Associations between physical function and device-based measures of physical activity and sedentary behavior patterns in older adults: moving beyond moderate-to-vigorous intensity physical activity 2021 Mar 31;21(1):216. doi: 10.1186/s12877-021-02163-4. Epub 2021-03-31. PubMed

Postupna N, Rose SE, Gibbons LE, Coleman NM, Hellstern LL, Ritchie K, Wilson AM, Cudaback E, Li X, Melief EJ, Beller AE, Miller JA, Nolan AL, Marshall DA, Walker R, Montine TJ, Larson EB, Crane PK, Ellenbogen RG, Lein ES, Dams-O'Connor K, Keene CD The Delayed Neuropathological Consequences of Traumatic Brain Injury in a Community-Based Sample 2021 Mar 16;12:624696. doi: 10.3389/fneur.2021.624696. Epub 2021-03-16. PubMed

 

Research

COVID-and-estrogen_op3_1col.jpg

COVID risks not meaningfully greater with estrogen-containing medications

Oral contraceptives, hormone therapy not linked to more severe COVID outcomes.

Research

Brain_atrophyartwork_keene_june_1col.jpg

Traumatic brain injury raises risk of brain atrophy

Study suggests pathology of brain cell loss after traumatic head injury is distinct from Alzheimer’s disease.

New findings

Suicide-risk-modeling-story_1col.jpg

Simpler models to identify suicide risk perform similarly to more complex ones

Models that are easier to explain, use could have better uptake in health care settings.