Article Text

Download PDFPDF

Body mass index and mortality in elderly men and women: the Tromsø and HUNT studies
  1. Jan-Magnus Kvamme1,2,
  2. Jostein Holmen3,
  3. Tom Wilsgaard1,
  4. Jon Florholmen2,4,
  5. Kristian Midthjell4,
  6. Bjarne K Jacobsen1
  1. 1Department of Community Medicine, University of Tromsø, Tromsø, Norway
  2. 2Department of Gastroenterology, University Hospital of North Norway, Tromsø, Norway
  3. 3HUNT Research Centre, Department of Public Health and General Practice, Norwegian University of Science and Technology, Levanger, Norway
  4. 4Laboratory of Gastroenterology and Nutrition, Institute of Clinical Medicine, University of Tromsø, Tromsø, Norway
  1. Correspondence to Jan-Magnus Kvamme, Department of Community Medicine, Faculty of Health Sciences, University of Tromsø, N-9037 Tromsø, Norway; jan-magnus.kvamme{at}uit.no

Abstract

Background The impact of body mass index (BMI; kg/m2) and waist circumference (WC) on mortality in elderly individuals is controversial and previous research has largely focused on obesity.

Methods With special attention to the lower BMI categories, associations between BMI and both total and cause-specific mortality were explored in 7604 men and 9107 women aged ≥65 years who participated in the Tromsø Study (1994–1995) or the North-Trøndelag Health Study (1995–1997). A Cox proportional hazards model adjusted for age, marital status, education and smoking was used to estimate HRs for mortality in different BMI categories using the BMI range of 25–27.5 as a reference. The impact of each 2.5 kg/m2 difference in BMI on mortality in individuals with BMI<25.0 and BMI≥25.0 was also explored. Furthermore, the relations between WC and mortality were assessed.

Results We identified 7474 deaths during a mean follow-up of 9.3 years. The lowest mortality was found in the BMI range 25–29.9 and 25–32.4 in men and women, respectively. Mortality was increased in all BMI categories below 25 and was moderately increased in obese individuals. U-shaped relationships were also found between WC and total mortality. About 40% of the excess mortality in the lower BMI range in men was explained by mortality from respiratory diseases.

Conclusions BMI below 25 in elderly men and women was associated with increased mortality. A modest increase in mortality was found with increasing BMI among obese men and women. Overweight individuals (BMI 25–29.9) had the lowest mortality.

  • Body mass index
  • waist circumference
  • aged
  • chronic disease
  • mortality, elderly
  • mortality si
  • nutrition
  • smoking rb

This is an open-access article distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited, the use is non commercial and is otherwise in compliance with the license. See: http://creativecommons.org/licenses/by-nc/2.0/ and http://creativecommons.org/licenses/by-nc/2.0/legalcode.

View Full Text

Statistics from Altmetric.com

Footnotes

  • Funding Centre for Research in the Elderly, The Northern Regional Health Authority, Helse Nord RHF, 8038 Bodø, Norway.

  • Competing interests None.

  • Ethics approval This study was conducted with the approval of the Regional Committees for Ethics in Medical Research, Tromsø and Trondheim, Norway, and by the Norwegian Data Inspectorate.

  • Provenance and peer review Not commissioned; externally peer reviewed.

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.