Concurrent and separate effects of body mass index and waist-to-hip ratio on 24-year mortality in the Population Study of Women in Gothenburg: Evidence of age-dependency
- 119 Downloads
Obesity is generally assumed to be an important risk factor for death and morbidity. However, the association between excess body weight and all-cause mortality among younger and older women and the impact of body mass index (BMI) and waist-to-hip ratio (WHR) concurrently is not fully understood. In 1968–1969 we initiated a prospective study comprising a population sample of 1,462 women from Gothenburg, Sweden. During a 24 year period, until 1992–1993, 265 women had died. A multivariable Cox Proportional Hazards Regression model was used to estimate the relative risk of death in relation to BMI and WHR, with age and other covariates of age-specific interest as smoking, physical activity at work and leisure time and serum triglyceride concentration, at start of the study. BMI and WHR were analyzed as independent variables. Younger women (38 and 46 years at baseline) presented a statistically significant non-linear (U-shaped) relation between BMI and mortality. Among older women (50, 54 and 60 years at baseline), a significant negative linear relationship with decreasing mortality in relation to increasing BMI values was seen. For all women a higher WHR was related to an increased risk of death. The lowest risk of death among younger women corresponded to a low WHR and a BMI within the middle range. For older women the highest survival was observed for those with lowest WHR and highest BMI. Thus, in older women a high BMI seems not to be an increased risk as long as adiposity is not centrally located.
KeywordsAge Body mass index Mortality Waist-to-hip ratio Women
Body mass index
Unable to display preview. Download preview PDF.
The study was supported by the Swedish Medical Council (27X-04578-27C), the Swedish Council for Planning and Coordination of Research (0950:5 A19-5/67), the Swedish Research Council (345-2001-6652, 27X-04578, 2002-3724), the Bank of Sweden Tercentary Foundation, and the Medical Faculty, the Sahlgrenska Academy at Göteborg University.
- 2.Bengtsson C, Björkelund C, Lapidus L, Lissner L (1993) Associations of serum lipid concentrations and obesity with mortality in women: 20 year follow up of participants in prospective population study in Gothenburg, Sweden. Br Med J 307: 1385–1388Google Scholar
- 6.Bengtsson C (1973) Ischaemic heart disease in women. A study based on a randomized population sample of women and women with myocardial infarction in Göteborg, Sweden. Thesis. Acta Med Scand 549(Suppl): 1–128Google Scholar
- 7.Bengtsson C, Ahlqvist M, Andersson K, Björkelund C, Lissner L, Söderström M (1997) The prospective Population Study of Women in Gothenburg, Sweden, 1968–69 to 1992–93. A 24 year follow up with respect to participation, representativeness and mortality. Scand J Prim Health Care 15: 214–219PubMedGoogle Scholar
- 8.SAS Institute Inc. (1999) SAS/STAT® User’s Guide, Version 8, SAS Institute Inc, Cary, NCGoogle Scholar
- 28.Obesity (1979) Preventing and managing the global epidemic. Report of WHO Consulting on Obesity, Geneva, 3–5 June 1997, WHO/NUT/NCD/98; 3–5 JuneGoogle Scholar