title: Analytic morphomics corresponds to functional status in older patients.
abstract: BACKGROUND
  Older patients account for nearly half of the United States surgical volume, and age alone is insufficient to predict surgical fitness. Various metrics exist for risk stratification, but little work has been done to describe the association between measures. We aimed to determine whether analytic morphomics, a novel objective risk assessment tool, correlates with functional measures currently recommended in the preoperative evaluation of older patients.
  
  
  METHODS
  We retrospectively identified 184 elective general surgery patients aged >70 y with both a preoperative computed tomography scan and Vulnerable Elderly Surgical Pathways and outcomes Assessment within 90 d of surgery. We used analytic morphomics to calculate trunk muscle size (or total psoas area [TPA]) and univariate logistic regression to assess the relationship between TPA and domains of geriatric function mobility, basic and instrumental activities of daily living (ADLs), and cognitive ability.
  
  
  RESULTS
  Greater TPA was inversely correlated with impaired mobility (odds ratio [OR] = 0.46, 95% confidence interval [CI] 0.25-0.85, P = 0.013). Greater TPA was associated with decreased odds of deficit in any basic ADLs (OR = 0.36 per standard deviation unit increase in TPA, 95% CI 0.15-0.87, P <0.03) and any instrumental ADLs (OR = 0.53, 95% CI 0.34-0.81; P <0.005). Finally, patients with larger TPA were less likely to have cognitive difficulty assessed by Mini-Cog scale (OR = 0.55, 95% CI 0.35-0.86, P <0.01). Controlling for age did not change results.
  
  
  CONCLUSIONS
  Older surgical candidates with greater trunk muscle size, or greater TPA, are less likely to have physical impairment, cognitive difficulty, or decreased ability to perform daily self-care. Further research linking these assessments to clinical outcomes is needed.
authors.affiliation: Department of Surgery, University of Michigan, Ann Arbor, Michigan; Department of Medicine, Division of Geriatric and Palliative Medicine, University of Michigan, Ann Arbor, Michigan. Electronic address: ashmil@med.umich.edu.
authors.forename: Ashley L
authors.initials: AL
authors.lastname: Miller
authors.affiliation: Department of Medicine, Division of Geriatric and Palliative Medicine, University of Michigan, Ann Arbor, Michigan; VA Ann Arbor Healthcare System and the Geriatric Research Education Clinical Center (GRECC), Ann Arbor, Michigan.
authors.forename: Lillian C
authors.initials: LC
authors.lastname: Min
authors.affiliation: Department of Surgery, University of Michigan, Ann Arbor, Michigan.
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Diehl
authors.affiliation: Department of Surgery, University of Michigan, Ann Arbor, Michigan.
authors.forename: David C
authors.initials: DC
authors.lastname: Cron
authors.affiliation: Department of Medicine, Division of Geriatric and Palliative Medicine, University of Michigan, Ann Arbor, Michigan.
authors.forename: Chiao-Li
authors.initials: CL
authors.lastname: Chan
authors.affiliation: Department of Surgery, University of Michigan, Ann Arbor, Michigan.
authors.forename: Kyle H
authors.initials: KH
authors.lastname: Sheetz
authors.affiliation: Department of Surgery, University of Michigan, Ann Arbor, Michigan.
authors.forename: Michael N
authors.initials: MN
authors.lastname: Terjimanian
authors.affiliation: Department of Surgery, University of Michigan, Ann Arbor, Michigan.
authors.forename: June A
authors.initials: JA
authors.lastname: Sullivan
authors.affiliation: Department of Surgery, University of Michigan, Ann Arbor, Michigan.
authors.forename: William C
authors.initials: WC
authors.lastname: Palazzolo
authors.affiliation: Department of Surgery, University of Michigan, Ann Arbor, Michigan.
authors.forename: Stewart C
authors.initials: SC
authors.lastname: Wang
authors.affiliation: Department of Medicine, Division of Geriatric and Palliative Medicine, University of Michigan, Ann Arbor, Michigan; VA Ann Arbor Healthcare System and the Geriatric Research Education Clinical Center (GRECC), Ann Arbor, Michigan.
authors.forename: Karen E
authors.initials: KE
authors.lastname: Hall
authors.affiliation: Department of Surgery, University of Michigan, Ann Arbor, Michigan.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Englesbe
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D003071:Cognition; D003430:Cross-Sectional Studies; D017558:Elective Surgical Procedures; D005260:Female; D015577:Geriatric Assessment / Q000379:methods*; D006801:Humans; D016015:Logistic Models; D008297:Male; D009043:Motor Activity; D018579:Patient Selection; D010809:Physical Fitness; D011300:Preoperative Care / Q000379:methods*; D016658:Psoas Muscles / Q000033:anatomy & histology* / Q000502:physiology; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods
keywords: Activities of daily living; Analytic morphomics; Functional status; Geriatric assessment; Mobility; Risk assessment; Trunk muscle size