Body Mass Index, Change in Body Mass Index, and Survival in Old and Very Old Persons
Article first published online: 1 MAR 2013
© 2013, Copyright the Authors Journal compilation © 2013, The American Geriatrics Society
Journal of the American Geriatrics Society
Volume 61, Issue 4, pages 512–518, April 2013
How to Cite
J Am Geriatr Soc 61:512–518, 2013.
- Issue published online: 14 APR 2013
- Article first published online: 1 MAR 2013
- Swedish Council for Working Life and Social Research. Grant Number: 2010–0704
- Future Leaders of Aging Research in Europe postdoctoral. Grant Number: 2010–1852
- National Institutes of Health, National Institute on Aging. Grant Numbers: NIA AG08861, R03 AG028471, R21-AG033109, RC1-AG035645, R21-AG032379, RC1-AG035645, R21-AG032379, R21-AG004132
- MacArthur Foundation Research Network on Successful Aging
- Axel and Margaret Ax:son Johnson Foundation
- Swedish Foundation for Health Care Sciences and Allergy Research
- King Gustaf V and Queen Viktoria Foundation
- body mass index;
To examine how body mass index (BMI) and change in BMI are associated with mortality in old (70–79) and very old (≥80) individuals.
Pooled data from three multidisciplinary prospective population-based studies: OCTO-twin, Gender, and NONA.
Eight hundred eighty-two individuals aged 70 to 95.
BMI was calculated from measured height and weight as kg/m2. Information about survival status and time of death was obtained from the Swedish Civil Registration System.
Mortality hazard was 20% lower for the overweight group than the normal–underweight group (relative risk (RR) = 0.80, P = .011), and the mortality hazard for the obese group did not differ significantly from that of the normal–underweight group (RR = 0.93, P = .603), independent of age, education, and multimorbidity. Furthermore, mortality hazard was 65% higher for the BMI loss group than for the BMI stable group (RR = 1.65, P < .001) and 53% higher for the BMI gain group than for the BMI stable group (RR = 1.53, P = .001). Age moderated the BMI change differences. That is, the higher mortality risks associated with BMI loss and gain were less severe in very old age.
Old persons who were overweight had a lower mortality risk than old persons who were of normal weight, even after controlling for weight change and multimorbidity. Persons who increased or decreased in BMI had a greater mortality risk than those who had a stable BMI, particularly those aged 70 to 79. This study lends further support to the belief that the World Health Organization guidelines for BMI are overly restrictive in old age.