title: Obesity and risk of non-Hodgkin lymphoma (United States).
abstract: OBJECTIVE
  Few studies have explored the potential association between body mass index (BMI) and non-Hodgkin lymphoma (NHL) according to histologic subtypes, or have evaluated BMI at different periods in the subject's life, and the results of these studies have been inconsistent.
  
  
  METHODS
  A population-based, case-control study of 387 patients with NHL and 535 controls conducted in Nebraska between 1999 and 2002.
  
  
  METHODS
  Information on usual adult weight, weight at the ages 20-29, 40-49, and 60-69 years, height, physical activity, and other lifestyle factors was collected by telephone interview. A self-administered semi-quantitative food frequency questionnaire was used to collect dietary intake. Risk was estimated by odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for age, total energy intake, physical activity, and other confounding factors.
  
  
  RESULTS
  Higher adult BMI was associated with risk of NHL (OR=1.4; 95% CI=0.9-2.0) comparing the obese group (BMI >or= 30.0 kg/m(2)) with the normal weight group (BMI=18.5-24.9 kg/m(2)). The risk was higher for those who were class 2 obese (BMI >or= 35.0 kg/m(2), OR=1.7; 95% CI=1.0-2.9). The positive association was similar among men and women. An excess risk of NHL was associated with high BMI at ages 40-49 years (OR=1.6; 95% CI=1.0-2.5), and to a lesser extent, at ages 20-29 years (OR=1.4; 95% CI=0.8-2.5). Obesity at ages 40-49 years was also associated with a higher risk of small lymphocytic lymphoma (OR=4.5; 95% CI=1.5-13.3), diffuse large B-cell NHL (OR=1.8; 95% CI=0.9-3.9) and follicular NHL (OR=1.8; 95% CI=0.9-3.5).
  
  
  CONCLUSIONS
  Obesity is associated with risk of NHL overall. Obesity at ages 40-49 years is also associated with a higher risk of NHL overall, and particularly small lymphocytic, follicular, and diffuse large B-cell NHL.
authors.affiliation: Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, 680 North Lake Shore Drive, Suite 1102, Chicago, IL 60611-4402, USA. bchiu@northwestern.edu
authors.forename: Brian C-H
authors.initials: BC
authors.lastname: Chiu
authors.forename: Lori
authors.initials: L
authors.lastname: Soni
authors.forename: Susan M
authors.initials: SM
authors.lastname: Gapstur
authors.forename: Angela J
authors.initials: AJ
authors.lastname: Fought
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Evens
authors.forename: Dennis D
authors.initials: DD
authors.lastname: Weisenburger
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D016022:Case-Control Studies; D016001:Confidence Intervals; D015930:Diet Records; D005260:Female; D006801:Humans; D007407:Interviews as Topic; D008228:Lymphoma, Non-Hodgkin / Q000453:epidemiology / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D009329:Nebraska / Q000453:epidemiology; D009765:Obesity / Q000150:complications* / Q000453:epidemiology; D016017:Odds Ratio; D012307:Risk Factors