Meredith L Wallace, PhD

Meredith L Wallace, PhD
Associate Professor of Psychiatry, Statistics and Biostatistics
University of Pittsburgh, Department of Psychiatry

I direct the Statistics for Sleep and Psychiatry research group.  Sleep plays a key role in many parts of our lives, including our daily functioning, mood, cognition, risk for substance use, and physical health.   This group is devoted to advancing statistics for psychiatry research – with a central focus on the role of sleep.   The two main goals for this group are: (1) to develop and apply cutting edge methods relevant for sleep research, especially with respect to how sleep predicts physical and mental health outcomes; and (2) to provide superior statistical support to investigators involved with research related to sleep and psychiatry.

Additional Links:

Center for Sleep and Circadian Science

Center for Adolescent Rhythms and Reward (CARRS)

Research

I am a biostatistician with a research emphasis on the development of statistical methods for studying sleep as a multidimensional construct.  Currently, I have a competing renewal focused on developing large, harmonized databases from multiple sleep cohorts of older adults. With these data, I apply state-of-the art machine learning and clustering to study the association between multivariable sleep health and health outcomes (mortality, cognition, depression) in older adults.  Separately, I have also been integral in demonstrating and applying statistical methods for optimal combined moderators that utilize machine learning to characterize subgroups of individuals for whom one treatment or experimental condition may have a desirable or undesirable effect relative to the other.  Finally, I am also an avid statistical collaborator with several ongoing projects across a wide range of areas of applications (e.g., sleep, substance use, health disparities) and data types (e.g., intensively measured data including ecological momentary assessment, actigraphy, and polysomnography).

Recent Selected Publications

  1. Wallace ML, Coleman TS, Mentch LK, et al. Physiological sleep measures predict time to 15-year mortality in community adults: Application of a novel machine learning framework. Journal of Sleep Research. 2021 May:e13386. doi: 10.1111/jsr.13386.
  2. Hasler BH, Soehner AS, Wallace ML, Logan RW, Ngari W, Forbes EE, Buysse DJ, Clark DB. Experimentally imposed circadian misalignment alters the neural response to monetary rewards and response inhibition in healthy adolescents. Psychol Med. 2021 Mar 17:1-9. doi: 10.1017/S0033291721000787.
  3. Price RB, Gillan C, Hanlon C, Ferrarelli F, Kim T, Karim HT, Renard MP, Kaskie R, Degutis M, Wears A, Vienneau EP, Peterchev AV, Brown V, Siegle GJ, Wallace ML, Ahmari SE. Experimental Manipulation of the Orbitofrontal Cortex Impacts Short-Term Markers of Human Compulsive Behavior: A Theta Burst Stimulation Study. The American Journal of Psychiatry. 2021 178:5, 459-468. https://doi.org/10.1176/appi.ajp.2020.20060821
  4. Wallace ML, Yu L, Buysse DJ, Stone K, Redline S, Smagula SF, Stefanick ML, Kritz-Silverstein D, Hall MH Multidimensional Sleep Health Domains in Older Men and Women: An Actigraphy Factor Analysis. SLEEP 2021 Sep 12;zsaa181. doi: 10.1093/sleep/zsaa181.
  5. Banihashemi L, Peng C, Verstynen T, Wallace ML, Lamont D, Alkhars H, Yeh F, Beeney J, Aizenstein H, Germain A. Opposing Relationships of Childhood Threat and Deprivation with Stria Terminalis White Matter. Human Brain Mapping 2021 1:42, 2445-2460. doi: 10.1002/hbm.25378.
  6. Mendez DD, Sanders SA, Lai Y-H, Wallace ML, Rathbun SL, Gary-Webb TL, Davis EM. Ecological Momentary Assessment of Stress, Racism and Other Forms of Discrimination During Pregnancy Using Smartphone Technology. Paediatr Perinat Epidemiol. 2020 Jan 13. doi: 10.1111/ppe.12619. [Epub Ahead of Print]
  7. Wallace ML, Lee S, Hall MH, Stoke K, Langsetmo L, Redline S, Schousboe JT, Ensrud K, LeBlanc ES, Buysse DJ for the MrOS and SOF Research Groups. Heightened Sleep Propensity: A Novel and High-Risk Sleep Health Phenotype in Older Adults. Sleep Health. 2019 Dec;5(6):630-638. doi: 10.1016/j.sleh.2019.08.001.
  8. Wallace ML, Buysse DJ, Redline S, Stone K, Ensrud K, Leng Y, Ancoli-Israel S, Hall MH. Multidimensional sleep and mortality in older adults: A machine-learning comparison with other risk factors. J Gerontol A Biol Sci Med Sci. 2019 Nov 13;74(12):1903-1909. doi: 10.1093/gerona/glz044. PubMed PMID: 30778527.
  9. Wallace ML, Banihashemi L, O’Donnell C, Nimgaonkar VL, Kodavali C, McNamee R, Germain A. Using optimal combined moderators to define heterogeneity in neural responses to randomized conditions: Application to the effect of sleep loss on fear learning. NeuroImage 2018 Nov 1;181:718-727. doi:1016/j.neuroimage.2018.07.051 PubMed PMID: 29480752.
  10. Wallace ML, Buysse DJ, Germain A, Hall MH, Iyengar S. Variable selection for skewed model-based clustering: Application to the identification of novel sleep phenotypes. J Am Stat Assoc. 2018; 113(521): 95-110.  doi: 10.1080/01621459.2017.1330202
  11. Wallace ML, Stone K, Smagula SF, Hall MH Simsek B, Kado D, Redline S, Vo Tien, Buysse DJ, Osteoporotic Fractures in Men (MrOS) Study Research Group. Which sleep health characteristics predict all-cause mortality in older men? An application of flexible multivariable methods. SLEEP. 2018 Jan 1; 41(1). doi: 10.1093/sleep/zsx189. PubMed PMID:


R01 Collaborators

I am grateful for my many amazing collaborators whose data and expertise make my work possible.

Students and Post-Doctoral Associates

Amanda Tapia, PhD

Bradley Wheeler, BS

University of Pittsburgh Investigators

Meryl Butters, MD, Department of Psychiatry, University of Pittsburgh, PA

Daniel Buysse, MD, Department of Psychiatry, University of Pittsburgh, PA

Martica Hall, PhD, Department of Psychiatry, University of Pittsburgh, PA

Lan Yu, Department of Medicine, University of Pittsburgh, PA

Lucas Mentch, Department of Statistics, University of Pittsburgh, PA

External Investigators

Lisa Barnes, PhD, Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL

Andrew Lim, MD, Department of Medicine, Sunnybrook Health Sciences Centre, Toronto

Yue Leng, PhD, Department of Psychiatry, University of California, San Francisco

Annemarie Luik, PhD, Department of Epidemiology, Erasmus Medical Center, Rotterdam Netherlands

Susan Redline, PhD, MD, Departments of Medicine, Brigham and Women’s Hospital and Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA

Katie L Stone, California Pacific Medical Center, San Francisco CA

Kristine Yaffe, MD, Departments of Psychiatry, Neurology and Epidemiology at University of California, San Francisco

Cohorts

Osteoporotic Fractures in Men Sleep Study (MrOS)

Study of Osteoporotic Fractures (SOF)

Sleep Heart Health Study (SHHS)

Memory and Aging Project (MAP)

Minority Aging Research Study (MARS)

Multi-Ethnic Study of Atherosclerosis (MESA)

Rotterdam Study (RT)

Wisconsin Sleep Cohort Study (WSCS)

Visit the National Sleep Research Resource at www.sleepdata.org  to learn more about these and available cohorts for sleep research.