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.
Survival and longitudinal data analysis; epidemiology; machine learning; two-phase sampling
Biostatistics; cognitive health and dementia; neuropathologic correlates of dementia; factors associated with healthy aging
Biostatistics; suicide risk prediction; interventions for risk reduction; machine learning and health informatics
Biostatistics; pharmacoepidemiology; medication safety in older adults; opioids and chronic pain
Bellettiere J, Tuz-Zahra F, Carlson JA, Ridgers ND, Liles S, Greenwood-Hickman MA, Walker RL, LaCroix AZ, Jankowska MM, Rosenberg DE, Natarajan L Agreement of sedentary behaviour metrics derived from hip-worn and thigh-worn accelerometers among older adults: with implications for studying physical and cognitive health 2021 Mar;4(1):79-88. doi: 10.1123/jmpb.2020-0036. Epub 2021-02-16. PubMed
Kumar RG, Jayasinghe N, Walker RL, Gibbons LE, Power MC, Larson EB, Crane PK, Dams-O'Connor K Association of remote traumatic brain injury and military employment with late-life trajectories of depressive symptom severity 2021 Feb 15;281:376-383. doi: 10.1016/j.jad.2020.12.003. Epub 2020-12-05. PubMed
Zhou J, Walker RL, Gray SL, Marcum ZA, Barthold D, Bowen JD, McCormick W, McCurry SM, Larson EB, Crane PK Glucose-Dementia Association is Consistent Over Blood Pressure/Antihypertensive Groups 2021 Jan;80(1):79-90. doi: 10.3233/JAD-201138. PubMed
Rosenberg D, Walker R, Greenwood-Hickman MA, Bellettiere J, Xiang Y, Richmire K, Higgins M, Wing D, Larson EB, Crane PK, LaCroix AZ Device-assessed physical activity and sedentary behavior in a community-based cohort of older adults 2020 Aug 18;20(1):1256. doi: 10.1186/s12889-020-09330-z. Epub 2020-08-18. PubMed
Dublin S, Walker RL, Floyd JS, Shortreed SM, Fuller S, Albertson-Junkans LH, Harrington LB, Greenwood-Hickman MA, Green BB, Psaty BM Renin-angiotensin-aldosterone system inhibitors and COVID-19 infection or hospitalization: a cohort study 2020 Jul 7 doi: 10.1101/2020.07.06.20120386. PubMed
Oral contraceptives, hormone therapy not linked to more severe COVID outcomes.
Study suggests pathology of brain cell loss after traumatic head injury is distinct from Alzheimer’s disease.
Models that are easier to explain, use could have better uptake in health care settings.