%0 Journal Article %T Body mass index and mortality in elderly men and women: the Tromso and HUNT studies %A Kvamme, J-M %A Holmen, J. %A Wilsgaard, T. %A Florholmen, J. %A Midthjell, K. %A Jacobsen, B. K. %J Journal of Epidemiology and Community Health %D 2012 %V 66 %N 7 %@ 0143-005X %G English %F Kvamme_etal2012 %O PMID:21321065; PMC3368492 %O exported from refbase (http://vev.medisin.ntnu.no/refbase/show.php?record=1537), last updated on Mon, 10 Mar 2014 14:36:27 +0100 %X BACKGROUND: The impact of body mass index (BMI; kg/m(2)) 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 Tromso Study (1994-1995) or the North-Trondelag 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/m(2) 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. %K Aged %K 80 and over %K *Body Mass Index %K Female %K Humans %K Male %K Mortality/*trends %K Norway/epidemiology %K Proportional Hazards Models %K Questionnaires %K Registries %R 10.1136/jech.2010.123232 %U http://www.ncbi.nlm.nih.gov/pubmed/21321065 %U https://doi.org/10.1136/jech.2010.123232 %P 611-617