title: Obesity and the Transformation of Monoclonal Gammopathy of Undetermined Significance to Multiple Myeloma: A Population-Based Cohort Study.
abstract: Multiple myeloma (MM) is one of the most common hematologic malignancies in the United States and is consistently preceded by monoclonal gammopathy of undetermined significance (MGUS). This study investigates the role of obesity in the progression of MGUS to MM.
  
  
  
  A retrospective identified cohort of patients in the US Veterans Health Administration database diagnosed with MGUS between October 1, 1999, and December 31, 2009, was followed through August 6, 2013. Patient-level clinical data were reviewed to verify MM diagnosis, if any. Survival analyses utilizing interval-censored data were used to investigate the risk of progression of MGUS to MM. Statistical tests were two-sided.
  
  
  
  The analytic cohort consisted of 7878 MGUS patients with a median follow-up of 68 months. Within the cohort, 39.8% were overweight and 33.8% were obese; 64.1% were of white race. During follow-up, 329 MGUS patients (4.2%) progressed to MM: 72 (3.5%) normal-weight patients (median follow-up = 61.9 months), 144 (4.6%) overweight patients (median follow-up = 69.1 months), and 113 (4.3%) obese patients (median follow-up = 70.6 months). In the multivariable analysis, overweight (hazard ratio [HR] = 1.55, 95% confidence interval [CI] = 1.16 to 2.06) and obesity (HR = 1.98, 95% CI = 1.47 to 2.68) were associated with an increased risk of transformation of MGUS to MM. Moreover, black race was associated with a higher risk of MM (HR = 1.98, 95% CI = 1.55 to 2.54).
  
  
  
  Obesity and black race are risk factors for transformation of MGUS to MM. Future clinical trials should examine whether weight loss is a way to prevent the progression to MM in MGUS patients.
authors.affiliation: Affiliations of authors: Research Service, St. Louis Veterans Affairs Medical Center, St. Louis, MO (SHC, SL, TST, KKO, KRC); Division of Public Health Sciences, Department of Surgery (SHC, GAC, NPC, KRC), and Division of Oncology, Department of Internal Medicine (SL, KKO, KRC), Washington University School of Medicine, St. Louis, MO.
authors.forename: Su-Hsin
authors.initials: SH
authors.lastname: Chang
authors.affiliation: Affiliations of authors: Research Service, St. Louis Veterans Affairs Medical Center, St. Louis, MO (SHC, SL, TST, KKO, KRC); Division of Public Health Sciences, Department of Surgery (SHC, GAC, NPC, KRC), and Division of Oncology, Department of Internal Medicine (SL, KKO, KRC), Washington University School of Medicine, St. Louis, MO.
authors.forename: Suhong
authors.initials: S
authors.lastname: Luo
authors.affiliation: Affiliations of authors: Research Service, St. Louis Veterans Affairs Medical Center, St. Louis, MO (SHC, SL, TST, KKO, KRC); Division of Public Health Sciences, Department of Surgery (SHC, GAC, NPC, KRC), and Division of Oncology, Department of Internal Medicine (SL, KKO, KRC), Washington University School of Medicine, St. Louis, MO.
authors.forename: Theodore S
authors.initials: TS
authors.lastname: Thomas
authors.affiliation: Affiliations of authors: Research Service, St. Louis Veterans Affairs Medical Center, St. Louis, MO (SHC, SL, TST, KKO, KRC); Division of Public Health Sciences, Department of Surgery (SHC, GAC, NPC, KRC), and Division of Oncology, Department of Internal Medicine (SL, KKO, KRC), Washington University School of Medicine, St. Louis, MO.
authors.forename: Katiuscia K
authors.initials: KK
authors.lastname: O'Brian
authors.affiliation: Affiliations of authors: Research Service, St. Louis Veterans Affairs Medical Center, St. Louis, MO (SHC, SL, TST, KKO, KRC); Division of Public Health Sciences, Department of Surgery (SHC, GAC, NPC, KRC), and Division of Oncology, Department of Internal Medicine (SL, KKO, KRC), Washington University School of Medicine, St. Louis, MO.
authors.forename: Graham A
authors.initials: GA
authors.lastname: Colditz
authors.affiliation: Affiliations of authors: Research Service, St. Louis Veterans Affairs Medical Center, St. Louis, MO (SHC, SL, TST, KKO, KRC); Division of Public Health Sciences, Department of Surgery (SHC, GAC, NPC, KRC), and Division of Oncology, Department of Internal Medicine (SL, KKO, KRC), Washington University School of Medicine, St. Louis, MO.
authors.forename: Nils P
authors.initials: NP
authors.lastname: Carlsson
authors.affiliation: Affiliations of authors: Research Service, St. Louis Veterans Affairs Medical Center, St. Louis, MO (SHC, SL, TST, KKO, KRC); Division of Public Health Sciences, Department of Surgery (SHC, GAC, NPC, KRC), and Division of Oncology, Department of Internal Medicine (SL, KKO, KRC), Washington University School of Medicine, St. Louis, MO.
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Carson
mesh_terms: D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D015897:Comorbidity; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D056865:Ideal Body Weight; D008297:Male; D008875:Middle Aged; D008998:Monoclonal Gammopathy of Undetermined Significance / Q000453:epidemiology*; D009101:Multiple Myeloma / Q000453:epidemiology* / Q000208:ethnology; D009765:Obesity / Q000453:epidemiology*; D050177:Overweight / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D014481:United States / Q000453:epidemiology; D044465:White People / Q000706:statistics & numerical data