[Body mass index and measures of adiposity among elderly adults]

To evaluate the nutritional status of elderly persons and to compare the correlation between the body mass index (BMI=kg/m2) with measures of adiposity and fat distribution among elderly and middle-aged adults.

Elderly persons (N=699; 60 years or older) and middle-aged adults (N=1,306; 40-59.9 years) participating in a population-based survey conducted in 1996 in the municipality of Rio de Janeiro were evaluated as to body mass index, arm, waist, and hip circumferences, skinfolds, and arm fat and muscle areas using standardized procedures. The cutoff points proposed by the World Health Organization for waist circumference, waist-to-hip ratio, and body mass index were used. Analyses were performed using the Spearman correlation coefficient and linear regression adjusted for age.

About 50% of elderly subjects were classified as overweight and more than 50% of women in all age groups had waist circumference and waist-to-hip ratio outside the normal range. Among men, these percentages were about 40% for waist circumference and 20% for waist-to-hip ratio. Among elderly subjects, the partial correlation (adjusted for age) between body mass index and measures of adiposity (waist circumference, skinfolds, and arm fat area) ranged from 0.45 to 0.85 for men and 0.55 to 0.86 for women. Weight and waist circumference were the variables more strongly correlated with body mass index among both elderly persons and adults.

The prevalence of overweight among elderly persons was high for both men and women. Body mass index shows a similar relationship with adiposity regardless of ageing.