Identification of frailty and sarcopenia in hospitalised older people.

BACKGROUND

People with frailty and/or sarcopenia have an increased risk of negative health outcomes. However, their diagnosis is often difficult. Considering the potential value of myostatin and follistatin as biomarkers of these conditions, we aimed to compare the association between both myokines and frailty and/or sarcopenia in post-hospitalised older people. In addition, the capability of myostatin and follistatin for identifying frailty and sarcopenia was compared with physical tests.

MATERIALS AND METHODS

Participants in this cross-sectional study consisted of 84 post-hospitalised patients immediately after discharge. Participants met the following inclusion criteria: aged ≥ 70 years, score of ≥20 on the Mini-Mental State Examination, and able to stand up and walk independently for at least 4 m. Serum myostatin and follistatin concentrations were measured by enzyme-linked immunosorbent assay. Body measures and results from 4 physical tests (hand grip, chair stand, 8-foot timed Up and Go (8TUG) and gait speed (GS)) were also recorded. Frailty was evaluated by the Fried index, and sarcopenia by the criteria of the European Working Group on Sarcopenia in Older People.

RESULTS

Myostatin concentration was lower and follistatin concentration higher in people with frailty or sarcopenia. Receiver operating characteristic curves indicated that GS and 8TUG tests had the greatest capability for identifying frailty. Myostatin was the only variable capable of identifying sarcopenia.

CONCLUSION

Myostatin may be a useful biomarker for sarcopenia in post-hospitalised older adults. However, it has a lower capability for identifying frailty than physical tests. Further studies using larger samples and these myokines together with other biomarkers are warranted.