BMI and all-cause mortality in older adults: a meta-analysis

Am J Clin Nutr. 2014 Apr;99(4):875-90. doi: 10.3945/ajcn.113.068122. Epub 2014 Jan 22.


Background: Whether the association between body mass index (BMI) and all-cause mortality for older adults is the same as for younger adults is unclear.

Objective: The objective was to determine the association between BMI and all-cause mortality risk in adults ≥65 y of age.

Design: A 2-stage random-effects meta-analysis was performed of studies published from 1990 to 2013 that reported the RRs of all-cause mortality for community-based adults aged ≥65 y.

Results: Thirty-two studies met the inclusion criteria; these studies included 197,940 individuals with an average follow-up of 12 y. With the use of a BMI (in kg/m2) of 23.0-23.9 as the reference, there was a 12% greater risk of mortality for a BMI range of 21.0-21.9 and a 19% greater risk for a range of 20.0-20.9 [BMI of 21.0-21.9; HR (95% CI): 1.12 (1.10, 1.13); BMI of 20.0-20.9; HR (95% CI): 1.19 (1.17, 1.22)]. Mortality risk began to increase for BMI >33.0 [BMI of 33.0-33.9; HR (95% CI): 1.08 (1.00, 1.15)]. Self-reported anthropometric measurements, adjustment for intermediary factors, and exclusion of early deaths or preexisting disease did not markedly alter the associations, although there was a slight attenuation of the association in never-smokers.

Conclusions: For older populations, being overweight was not found to be associated with an increased risk of mortality; however, there was an increased risk for those at the lower end of the recommended BMI range for adults. Because the risk of mortality increased in older people with a BMI <23.0, it would seem appropriate to monitor weight status in this group to address any modifiable causes of weight loss promptly with due consideration of individual comorbidities.

Publication types

  • Meta-Analysis

MeSH terms

  • Aged
  • Aged, 80 and over
  • Aging*
  • Body Mass Index
  • Humans
  • Longitudinal Studies
  • Mortality
  • Obesity / physiopathology
  • Overweight / physiopathology*
  • Thinness / physiopathology*
  • Weight Loss