BMI and obesity in US blood donors: a potential public health role for the blood centre.
OBJECTIVE
According to the 2007-2008 National Health and Nutrition Examination Survey, the prevalence of obesity in the US population was 33·8 %; 34·3 % and 38·2 %, respectively, in middle-aged men and women. We asked whether available blood donor data could be used for obesity surveillance.


METHODS
Cross-sectional study of BMI and obesity, defined as BMI ≥ 30·0 kg/m2. Adjusted odds ratios (aOR) were calculated with logistic regression.


METHODS
A network of six US blood centres.


METHODS
Existing data on self-reported height and weight from blood donors, excluding persons deferred for very low body weight.


RESULTS
Among 1 042 817 donors between January 2007 and December 2008, the prevalence of obesity was 25·1 %; 25·7 % in men and 24·4 % in women. Obesity was associated with middle age (age 50-59 years v. <20 years: aOR = 1·92 for men and 1·81 for women), black (aOR = 1·57 for men and 2·35 for women) and Hispanic (aOR = 1·47 for men and 1·49 for women) race/ethnicity compared with white race/ethnicity, and inversely associated with higher educational attainment (college degree v. high school or lower: aOR = 0·56 for men and 0·48 for women) and double red cell donation and platelet donation.


CONCLUSIONS
Obesity is common among US blood donors, although of modestly lower prevalence than in the general population, and is associated with recognized demographic factors. Blood donors with higher BMI are specifically recruited for certain blood collection procedures. Blood centres can play a public health role in obesity surveillance and interventions.
Laboratory Medicine and Epidemiology/Biostatistics, University of California San Francisco, San Francisco, CA, USA. murphy@ucsf.edu
Edward L
EL
Murphy
Karen
K
Schlumpf
David J
DJ
Wright
Ritchard
R
Cable
John
J
Roback
Ronald
R
Sacher
Michael P
MP
Busch
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001782:Blood Donors; D001792:Blood Platelets; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D004522:Educational Status; D004912:Erythrocytes; D005260:Female; D006630:Hispanic or Latino; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009749:Nutrition Surveys; D009765:Obesity / Q000453:epidemiology*; D015995:Prevalence; D014481:United States / Q000453:epidemiology; D044465:White People; D055815:Young Adult