Obesity and excess in fat versus lean mass is well known to enhance the risk of mortality and morbidity. Several recent works have pointed the importance of analysing more precisely body composition for the assessment of prognosis of patients in terms of cardiovascular outcomes and mortality. The body mass index (BMI), commonly used for defining obese patients, does not give sufficient indication on the body composition and distribution of fat mass. In the elderly population, relative excess in fat mass associated with a decrease in lean mass is frequently observed. In such situations of sarcopenic obesity, the relative weight stability can be misleading. Sarcopenic obesity is an emerging public health problem in the geriatric population. It appears to be the situation with the worst prognosis for cardiovascular risk. In addition, recent works have highlighted the major impact of visceral fat, clearly linked with cardiovascular events. Body composition has also an impact on other pathologic conditions such as dementia, sleep apnoea or cancer. The links between body composition and morbidity in the elderly population are presented in this review, with emphasis on adipokines and their interactions with other organs such as the heart, liver, skeletal muscle or bones. More precise measurements of body composition, rather than BMI alone, should be developed in the elderly population.
Keywords: body composition; body mass index; comorbidity; obesity; sarcopenia.