title: Association between obesity and vulnerability and serologic response to influenza vaccination in older adults.
abstract: BACKGROUND
  Serologic response to influenza vaccination declines with age. Few other host factors are known to be associated with serologic response. Our objective was to determine whether obesity and vulnerability independently predicted serologic response to influenza vaccination.
  
  
  METHODS
  Adults ≥ 50 years were recruited during the 2008-2009 influenza season. Subjects provided pre- and post-vaccination sera for measuring antibody titers to 2008-2009 vaccine components. Body mass index (BMI) was calculated as weight (kg)/height (m(2)). Data were collected on vulnerability using the vulnerable elders survey (VES13). Logistic regression evaluated the associations between obesity and vulnerability and the serologic response to vaccination (both seroprotection and seroconversion), adjusting for gender, age, comorbidities, pre-vaccination titer, and site.
  
  
  RESULTS
  Mean (± standard deviation) age of 415 study subjects was 65 ± 10 years; 40% were obese. Mean BMI was 29 ± 5.6 kg/m(2); mean VES13 was 1.6 ± 1.8. The proportions of subjects who seroconverted and had seroprotective titers were 40% and 49%, respectively, for A/Brisbane/59 (H1N1); 73% and 80% for A/Brisbane/10 (H3N2); and 34% and 94% for B/Florida. Modified VES-13 (score 0-10, with 10 being most vulnerable) was not associated with seroprotection against H1N1 or H3N2, and VES-13 was directly associated with seroconversion to H1N1 but not H3N2 or B. Obesity (BMI ≥ 30 kg/m(2) vs. BMI 18.5-30 kg/m(2)) was not associated with seroprotection for H1N1 or H3N2; obesity was directly associated with seroconversion to H3N2 but not H1N1 or B. Age was inversely associated with seroprotection and seroconversion against H1N1 and with seroconversion to influenza B.
  
  
  CONCLUSIONS
  Based on this sample of older healthy subjects, there were no consistent relationships between VES 13 or obesity and either seroprotection or seroconversion to three influenza vaccine antigens.
authors.affiliation: Vanderbilt University, Nashville, TN.
authors.forename: H K
authors.initials: HK
authors.lastname: Talbot
authors.affiliation: Marshfield Clinic Research Foundation, Marshfield, WI.
authors.forename: L A
authors.initials: LA
authors.lastname: Coleman
authors.affiliation: Vanderbilt University, Nashville, TN.
authors.forename: K
authors.initials: K
authors.lastname: Crimin
authors.affiliation: Vanderbilt University, Nashville, TN.
authors.forename: Y
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Vanderbilt University, Nashville, TN.
authors.forename: M T
authors.initials: MT
authors.lastname: Rock
authors.affiliation: Marshfield Clinic Research Foundation, Marshfield, WI.
authors.forename: J
authors.initials: J
authors.lastname: Meece
authors.affiliation: U.S. Centers for Disease Control and Prevention, Atlanta, GA.
authors.forename: D K
authors.initials: DK
authors.lastname: Shay
authors.affiliation: Marshfield Clinic Research Foundation, Marshfield, WI.
authors.forename: E A
authors.initials: EA
authors.lastname: Belongia
authors.affiliation: Vanderbilt University, Nashville, TN.
authors.forename: M R
authors.initials: MR
authors.lastname: Griffin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood; D015992:Body Mass Index; D005260:Female; D005431:Florida; D006801:Humans; D007252:Influenza Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000276:immunology*; D011795:Surveys and Questionnaires; D014611:Vaccination / Q000379:methods*; D035862:Vulnerable Populations
chemical_list: D000914:Antibodies, Viral; D007252:Influenza Vaccines