An adequate threshold for body mass index to detect underweight condition in elderly persons: the Italian Longitudinal Study on Aging (ILSA).

Background: The present study aims at defining a body mass index (BMI) threshold for risk of being underweight in elderly persons on the basis of the BMI distribution in a large Italian population-based sample and on its ability to predict short-term mortality.

Methods: At baseline (1992), BMI was obtained for 3110 (1663 males and 1447 females) persons aged 65-84 participating in the Italian Longitudinal Study on Aging (ILSA). BMI and risk factors (age, sex, education, smoking status, disability, and disease status) have been considered for their potential association with 4-year all-cause mortality.

Influence of fat-free mass and functional status on resting energy expenditure in underweight elders.

Background: In underweight elders, resting energy expenditure (REE) and its relationship with fat-free mass (FFM) could be modified by sarcopenia, physical activity, and functional limitation. The aims of this study were to investigate REE and its relationship with quantity and metabolic activity of FFM and to evaluate the influence of functional status on REE in underweight elderly subjects.

Methods: Forty-eight underweight elders (BMI < 20) and 54 normal weight elderly subjects (BMI 20-30) as a control group were selected.

Anthropometric measurements in the elderly: age and gender differences.

In clinical practice and epidemiological surveys, anthropometric measurements represent an important component of nutritional assessment in the elderly. The anthropometric standards derived from adult populations may not be appropriate for the elderly because of body composition changes occurring during ageing. Specific anthropometric reference data for the elderly are necessary.