Osteosarcopenia and frailty: a review

Abstract

Coexistence of osteoporosis and sarcopenia, known as osteosarcopenia, is well documented in frailty development in elderly people. Osteosarcopenia is associated with poor outcomes in terms of morbidity and mortality. This study aims to review the epidemiology and interactions of osteosarcopenia with frailty among older adults. Exercise seems to produce promising results in osteosarcopenic elderly people. Multidisciplinary assessment and management is the gold standard of care. Department of Rehabilitation and Extended Care, Wong Tai Sin Hospital, Hong Kong Correspondence to: Dr Ka Ying Doris Miu, Department of Rehabilitation and Extended Care, Wong Tai Sin Hospital, 124 Shatin Pass Road, Hong Kong. Email: miuky@ha.org.hk adjusted skeletal muscle mass of <7.26 kg/m2 in men and 5.45 kg/m2 in women as measured by DXA or <8.5 kg/m2 in men and 5.75 kg/m2 in women measured by BIA. A hand grip strength of <30 kg in men and <20 kg in women is considered at risk of sarcopenia. As body build differs between ethnic groups, the Asian Working Group for Sarcopenia (AWGS) defines sarcopenia as a height adjusted skeletal muscle mass of <7 kg/m2 in men and <5.4 kg/m2 in women measured by DXA and <7 kg/m2 in men and <5.7 kg/m2 in women measured by BIA, with a gait speed <0.8 m/s and a cut-off value of hand grip strength of <26 kg in men and <18 kg in women.8 In addition, there is a subgroup of elderly people who have both conditions with a higher risk of falls and fracture than those with osteoporosis or sarcopenia alone.9 This is known as sarco-osteopenia and later as osteosarcopenia. Studies have reported the association between osteosarcopenia and poor outcomes.10-12 Frailty is a major geriatric syndrome and is associated with greater prevalence of adverse health outcomes, including mortality, institutionalisation, falls, and recurrent hospitalisation.13-15 Frailty consists of multidimensional syndromes of loss of energy, physical activity, cognition, and health. There are many definitions of frailty.13,16,17 Fried et al16 defined frailty as the presence of three or more of the following syndromes: unintentional weight loss, INTRODUCTION With the growth of the ageing population, osteoporosis and sarcopenia are emerging.1,2 Osteoporosis is defined as low bone mass and micro-architectural deterioration of bone tissue.3 According to the World Health Organization (WHO) criteria, a t-score of bone mineral density of <–2.5 is considered as osteoporotic.4 In clinical settings, osteoporosis is defined by the WHO bone mineral density criteria or the occurrence of a fragility fracture. Osteoporosis leads to increased bone fragility and fracture risk. In Asian countries, the age-standardised annual incidence of hip fractures is higher than that in the USA and some European countries.5 Osteoporotic fractures in elderly people can result in hospitalisation, institutional care, impaired quality of life, disability, and even death.6 Sarcopenia is defined as decreased muscle mass and physical performance and varies between countries (Table). The European Working Group on Sarcopenia in Older People (EWGSOP) defines sarcopenia as a syndrome characterised by progressive and generalised loss of skeletal muscle mass and strength with a risk of adverse outcomes such as physical disability, poor quality of life, and high mortality.7 Diagnosis can be made by either dual-energy X-ray absorptiometry (DXA) or bioelectrical impedance analysis (BIA) and/or low muscle function/strength. The EWGSOP defines sarcopenia as a gait speed of <0.8 m/s with a height