Relation between adipose tissue and the musculoskeletal unit in a group of postmenopausal women

Introduction
Involutional changes observed during aging increase rapidly in the postmenopausal period. These changes include body composition by affecting bone, muscle and fat tissue. A number of studies have investigated the mutual interaction between bone and muscle tissue, whereas adipose tissue had not been studied thoroughly. The aim of the present study was to assess the relation between fat tissue parameters and the musculoskeletal unit.

Material and methods
The study was conducted in a group of 120 postmenopausal women with an average age of 69 years (59–81; SD 5.3). All women had been asked to complete a questionnaire (medical history) and underwent a total body composition analysis [bone mineral density (BMD)] testing (spine and/or neck) followed by a handgrip test.

Results
The study revealed strong correlations between appendicular skeletal muscle mass index – appen.lean/height2, visceral adipose tissue area (VAT) and fat/mass/height2 index (r = 0.589 and 0.658 respectively; p < 0.001). The results were not supported by muscle strength (handgrip). The authors identified correlations between the bone parameters and adipose tissue but these were identified as weak or moderate (p < 0.05). Special emphasis should be placed on the relation between the trabecular bone score (TBS) and VAT area (r = –0.385, p < 0.001).

Conclusions
There is a strong dependence between muscle and adipose tissues. Despite the fact that the increase in fat is correlated with the growth of muscle tissue, it is not accompanied by better quality of the muscle (handgrip). Bone microarchitecture is more related to VAT area than neck/spine BMD.