OBJECTIVE: To investigate how categorizing body mass index (BMI) into weight classes can impact the assessment of the relationship between BMI and in-hospital mortality after coronary artery bypass graft (CABG) surgery. STUDY DESIGN AND SETTING: BMI-mortality (in-hospital) relationship was assessed in 5,762 patients who underwent isolated CABG at Baylor University Medical Center (Dallas, TX) from January 1, 1997 to November 30, 2003. Different ways of modeling BMI were used to investigate this association in a propensity-adjusted model, controlling for risk factors identified by the Society of Thoracic Surgeons (STS) and other clinical/nonclinical details. RESULTS: A highly significant (P=0.003) association between BMI (modeled with a restricted cubic spline) and mortality was found. Reduced risk of in-hospital mortality was observed for subjects with BMI in the low-30s as compared with patients with BMI in the mid-20s or over 40 kg/m(2). Results were strongly affected by the way BMI was specified in the multivariable model. Only five of the 10 BMI categorizations considered produced significant results, and these results did not fully determine the effect of BMI on mortality. CONCLUSIONS: BMI categorization critically impacts study results. Conceivably, findings of other studies investigating BMI and adverse outcomes after CABG may be similarly affected. Investigators should consider smoothing techniques to avoid categorization.
OBJECTIVE: To investigate how categorizing body mass index (BMI) into weight classes can impact the assessment of the relationship between BMI and in-hospital mortality after coronary artery bypass graft (CABG) surgery. STUDY DESIGN AND SETTING: BMI-mortality (in-hospital) relationship was assessed in 5,762 patients who underwent isolated CABG at Baylor University Medical Center (Dallas, TX) from January 1, 1997 to November 30, 2003. Different ways of modeling BMI were used to investigate this association in a propensity-adjusted model, controlling for risk factors identified by the Society of Thoracic Surgeons (STS) and other clinical/nonclinical details. RESULTS: A highly significant (P=0.003) association between BMI (modeled with a restricted cubic spline) and mortality was found. Reduced risk of in-hospital mortality was observed for subjects with BMI in the low-30s as compared with patients with BMI in the mid-20s or over 40 kg/m(2). Results were strongly affected by the way BMI was specified in the multivariable model. Only five of the 10 BMI categorizations considered produced significant results, and these results did not fully determine the effect of BMI on mortality. CONCLUSIONS: BMI categorization critically impacts study results. Conceivably, findings of other studies investigating BMI and adverse outcomes after CABG may be similarly affected. Investigators should consider smoothing techniques to avoid categorization.
Authors: Castigliano M Bhamidipati; Damien J LaPar; Gaurav S Mehta; John A Kern; Gilbert R Upchurch; Irving L Kron; Gorav Ailawadi Journal: Surgery Date: 2011-10 Impact factor: 3.982
Authors: Mani Arsalan; Giovanni Filardo; Won-Keun Kim; John J Squiers; Benjamin Pollock; Christoph Liebetrau; Johannes Blumenstein; Jörg Kempfert; Arnaud Van Linden; Annika Arsalan-Werner; Christian Hamm; Michael J Mack; Helge Moellmann; Thomas Walther Journal: Clin Res Cardiol Date: 2016-08-17 Impact factor: 5.460
Authors: Marcovalerio Melis; Jill M Weber; James M McLoughlin; Erin M Siegel; Sarah Hoffe; Ravi Shridhar; Kiran K Turaga; George Dittrick; E Michelle Dean; Richard C Karl; Kenneth L Meredith Journal: Ann Surg Oncol Date: 2010-09-24 Impact factor: 5.344
Authors: Jimmy T Efird; Preeti Gudimella; Wesley T O'Neal; William F Griffin; Hope Landrine; Linda C Kindell; Stephen W Davies; Daniel F Sarpong; Jason B O'Neal; Patricia Crane; Margaret A Nelson; Thomas Bruce Ferguson; Walter Randolph Chitwood; Alan P Kypson; Ethan J Anderson Journal: Am J Cardiol Date: 2016-01-15 Impact factor: 2.778
Authors: Mani Arsalan; Ethan Ungchusri; Robert Farkas; Melissa Johnson; Rebeca J Kim; Giovanni Filardo; Benjamin D Pollock; Molly Szerlip; Michael J Mack; Elizabeth M Holper Journal: Proc (Bayl Univ Med Cent) Date: 2018-02-23
Authors: Alexander M Strasak; Stefan Lang; Thomas Kneib; Larry J Brant; Jochen Klenk; Wolfgang Hilbe; Willi Oberaigner; Elfriede Ruttmann; Lalit Kaltenbach; Hans Concin; Günter Diem; Karl P Pfeiffer; Hanno Ulmer Journal: Ann Epidemiol Date: 2008-10-04 Impact factor: 3.797