Age-related changes of body composition and abdominal adipose tissue assessed by bio-electrical impedance analysis and computed tomography

Abstract

Only scarce information is available on body composition changes with age measured simultaneously by electrical impedance and computed tomography. AimWe aimed to describe the age-related changes of the body composition and adipose tissue distribution in Bulgarians. Material and methodsThis cross-sectional study included 130 participants (mean age 53±9.8 years, range 35–65), divided according to their body mass index (BMI): BMI<25.0kg/m2 (18 women, 12 men); BMI 25.0–34.9kg/m2 (50 women, 50 men). Body composition was assessed by bioelectrical impedance on a Tanita TBF-215 analyzer (Tanita Corp., Tokyo, Japan). The abdominal fat was measured by computed tomography on a CT/L scanner (GE Medical Systems, USA). ResultsIncreasing age was associated with a mean decrease in body weight by 268g per year in the normal weight subjects and by 390g in the overweight ones as well as with a fat-free mass decrease of 321g and of 291g per year respectively (p<0.001). One year of increasing age was associated with a mean increase of visceral adipose tissue by 2.43cm2 in the overweight group and by 2.68cm2 in the normal weight subjects and with a decrease of the subcutaneous adipose tissue by 2.30cm2 per year in the latter group (p<0.001). The association of fat mass and fat-free mass with age in men and women was best described by quadratic equations (both increased until the age of 45–50 and decreased thereafter). ConclusionsOur data showed a significant association between age and decreasing fat-free mass, increasing fat mass and abdominal fat accumulation.