Osteoporosis and sarcopenia: the connections.

Osteoporosis and sarcopenia are the most frequent musculoskeletal disorders affecting older people. Osteoporosis is a widespread disorder affecting millions of individuals of all ethnic backgrounds worldwide, particularly among older women. It is characterized by reduced bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in the risk of fracture. Sarcopenia is considered to be one of the major factors responsible for functional limitations and motor dependency in elderly persons. In age-related muscle atrophy, a decrease in muscle fiber size and number, and a preferential loss of type II fibers have been reported. A decrease in the circulating levels of specific hormones (e.g., estrogen, testosterone, growth hormone, and insulin-like growth factor-1) has been shown to be associated with sarcopenia and this appears to play an important role in its pathogenesis.