Perioperative neurocognitive and functional neuroimaging trajectories in older APOE4 carriers compared with non-carriers: secondary analysis of a prospective cohort study

Dr. Browndyke is an Associate Professor of Behavioral Health & Neurosciences in the Department of Psychiatry & Behavioral Sciences.  He has a secondary appointment as Assistant Professor of Cardiovascular & Thoracic Surgery.

Dr. Browndyke's research interests involve the use of advanced neurocognitive and neuroimaging techniques for perioperative contributions to delirium and later dementia risk, monitoring of late-life neuropathological disease progression, and intervention/treatment outcomes.  His research also involves novel telehealth methods for remote neurocognitive evaluation and implementation of non-invasive neuromodulatory techniques to assist in postoperative recovery and dementia risk reduction.

Dr. Browndyke's clinical expertise is focused upon geriatric neuropsychology with an emphasis in the assessment, diagnosis, and treatment of dementia and related disorders in adults and US veteran patient populations.

Katherine Martucci Ph.D. is a neuroscientist who specializes in human clinical research of chronic pain, reward and motivation behaviors, sensory and acute pain perception, and opioid use and addiction. Dr. Martucci serves as Director of the Human Affect and Pain Neuroscience Lab which uses a combination of neuroimaging techniques, including functional magnetic resonance imaging (fMRI) of the brain and cervical spinal cord, as well as sensory, behavioral and psychological tests to study acute and chronic pain in humans.

   As part of the Center for Translational Pain Medicine (CTPM), Dr. Martucci’s lab is part of Duke University’s Department of Anesthesiology, conducting research in collaboration with the Brain Imaging and Analysis Center (BIAC) and Duke Institute for Brain Sciences (DIBS).

   Dr. Martucci earned her Ph.D. in Neurobiology and Anatomy at Wake Forest School of Medicine and continued her training in clinical research with a postdoctoral fellowship at Stanford University. While at Stanford, Dr. Martucci obtained a prestigious NIH K99 “Pathway to Independence Award”. Since joining Duke University in 2018, Dr. Martucci has acquired funding via multiple NIH grants to continue her line of neuroimaging clinical research of the central nervous system in chronic pain.

My work uses translational neuroscience approaches, such as cerebrospinal fluid molecular assays, sleep EEG, cognitive testing, and delirium assessment to identify mechanisms of delirium. Delirium is a syndrome of disrupted attention and consciousness that occurs in ~20% of the >19 million older surgery patients and ~50% of the >5 million intensive care unit (ICU) patients in the United States every year. Delirium is also associated with increased risk for Alzheimer’s disease and related dementias (ADRD), yet there are no FDA-approved drugs to prevent it, due to a major gap in our understanding of its underlying mechanisms.  Our current work aims to discover potential mechanisms of delirium that could be targeted in future studies. We have recently found that increased blood-brain barrier dysfunction is associated with postoperative delirium, but it is unknown what inflammatory mediators actually cross the disrupted blood-brain barrier to drive delirium. Using mass spectrometry proteomics, we are examining the relationship of proteins and inflammatory markers found in the cerebrospinal fluid 24-hours following surgery with postoperative delirium. We are also interested in strategies that potentially protect the blood-brain barrier following surgery. Since sleep disruptions can cause blood-brain barrier dysfunction, we are conducting a study to determine the efficacy of suvorexant to improve postoperative sleep and reduce delirium severity in older surgical patients. Finally, we are working to extend these investigations to ICU patients, who are often more severely affected by delirium and more frequently develop long-term sequelae such as post-ICU long-term cognitive impairment (that is similar in magnitude to Alzheimer’s disease and related dementias).

Research efforts are focused primarily in the area of functional genomics. Work has centered on investigating genetic polymorphisms in the surgical intensive care population that would predispose one to the development of the sepsis syndrome. As an extension of this work, there is ongoing investigation working to identify genetically susceptible populations at risk for developing various types of perioperative organ dysfunction. Parallel studies involve identification of a panel of biomarkers that would enable early diagnosis and intervention for those patients, both surgical and non-surgical that develop the sepsis syndrome. There is also active investigation in the human pharmacology laboratory in the department of anesthesiology involving the phase 1 testing of novel pharmaceutical agents in healthy volunteers.

Dr. Whitson's research is focused on improving care options and resilience for people with multiple chronic conditions.  In particular, she has interest and expertise related to the link between age-related changes in the eye and brain (e.g., How does late-life vision loss impact the aging brain or cognitive outcomes?  Is Alzheimer's disease associated with distinctive changes in the retina, and could such changes help diagnose Alzheimer's disease early in its course?).  Dr. Whitson leads a collaborative Alzheimer's Disease initiative that brings together investigators from Duke University and the University of North Carolina (UNC) at Chapel Hill, with a bold vision to transform dementia research and care across Eastern North Carolina. Dr. Whitson is also interested in improving health services to better meet the needs of medically complex patients.  Within the Duke Aging Center, she leads research efforts aimed at promoting resilience to late-life stressors (e.g., surgery, sensory loss, infection).  She has developed a novel rehabilitation model for people with co-existing vision and cognitive deficits, and she is part of a inter-disciplinary team seeking to improve peri-operative outcomes for frail or at-risk seniors who must undergo surgery.  As a co-leader of a national resilience collaborative, she seeks to better understand the biological and psychological factors that determine how well we "bounce back" after health stressors.  

Dr. Cohen's research program includes clinical research relating to aspects of the pathways to functional decline and reilience with aging, geriatric assessment, and cancer and anemia in the elderly.

Pathways to functional decline are being explored through the NIA funded Claude Pepper Older Americans Independence Center, and includes studies of the contributions of age related physiologic change, in particular changes in inflammatory parameters, comorbid diseases and conditions, environment, genetics, and the interactionas among them. Data are derived from several current studies as well as previously collected data sets from the Established Populations for Epidemiologic Studies of the Elderly (EPESE), National Long Term Care Survey, and the Chinese Longevity Study (with Dr. Zeng Yi). Previous work has demonstrated the important contributions of age related inflammation and coagulation activation to functional status. He is Co-PI of the Pepper Center Physical Performance Across the LifeSpan (PALS) study, which is a longitudinal cohort study of community dwelling adults from age 30-90+and includes functional measures and biomarkers on inflammation and metabolism.
 
Geriatric assessment approaches have been studied in a number of randomized and controlled studies and work is now concentrating on the application of Comprehensive Geriatric Assessment tools to the evaluation and treatment of elderly patients with cancer. This is an extension and continuation of a long standing interest in geriatric oncology. Previous studies have elucidated age-related patterns of disease presentation, treatment approaches, clinical trials, survivorship, quality of life, impact of comrobidities and functional outcomes. Dr. Cohen was co-chair, and now member of the Cancer in the Older Adult Committee of the Alliance for Clinical Trials in Oncology (ALLIANCE). A number of active studies and ongoing data bases aree being utilized to address these questions.


Anemia in the older adult is being addressed through an NIA funded U01 consortium (Dr. Cohen Co-PI). the current main study is an observational study followed by a pragmatic treatment trial for anemia in older adults with CHF, in collaboration with the Cardiovascular Research Network (CVRN) of the Health services research network (HSRN)