Sarcopenia, Frailty and Clinical Practice in Older People

The mission of the MRC Lifecourse Epidemiology Unit is to provide a centre of excellence which uses epidemiological methods to promote human health by delineating the environmental and occupational causes throughout the lifecourse of: (1) chronic musculoskeletal disorders (osteoporosis, osteoarthritis and sarcopenia); and (2) metabolic disorders (diabetes mellitus, obesity and cardiovascular disease). Through understanding these causes, we aim to develop population-based and high risk preventive strategies against these disorders. This programme will explore the mechanisms which underlie the ageing of human muscle, and lead to physical frailty in later life.

We will establish an ageing research programme that builds on our progress to date in the fields of sarcopenia and cognition, and capitalises on our expertise in these areas to investigate their links with frailty and wellbeing. Our aim is to carry out high quality interdisciplinary ageing research that informs clinical practice and translates into the improved health of older people. We will focus on mechanisms, lifecourse influences, clinical consequences and interventions. In a group of HCS participants, we will examine the contribution of altered muscle fibre composition, reduction in muscle fibre number and size, and reduced capillary density to the link between small size at birth and sarcopenia. Understanding the cellular mechanisms underlying the association between birthweight and sarcopenia has the potential to inform clinical practice in older people with regard to both prediction and prevention. As part of the HALCyon research programme, we will use data from nine UK cohorts to investigate influences over the lifecourse on cognitive and physical capability and psychological wellbeing in later life. We will also examine the longitudinal relation between sarcopenia and physical frailty and subsequent wellbeing and cognitive function. Study of the inter-relationships between cognition, wellbeing, sarcopenia and frailty across the lifecourse will enable causal associations to be identified and inform the timing of interventions to maximise capability and wellbeing in later life. We will carry out two studies to elucidate the consequences of sarcopenia, frailty and chronic disease for receipt of hospital care. Firstly, by linkage of the existing HCS data to routine Hospital Episode Statistics data, we will investigate the association between sarcopenia, frailty and chronic disease and incidence of hospital admission. Secondly, in patients aged over 80 admitted to the Acute Medical Unit in Southampton, we will examine how these conditions influence length of stay and adverse clinical outcomes. The findings from these studies have the potential to inform both clinical practice and health policy. Finally, we plan to develop two clinical interventions for sarcopenia and frailty. In the first study, of community dwelling older people participating in the Hertfordshire Physical Activity Trial, we will assess the short- and long-term effects of exercise training on sarcopenia, physical performance, frailty and wellbeing. In the second study, of hospitalised older people, we will investigate whether the use of volunteers to provide mealtime assistance can improve dietary intake and clinical outcome through an effect on these conditions. This programme will permit investigation of the mechanisms underlying the developmental origins of sarcopenia, identify inter-relationships between sarcopenia, cognition, frailty and wellbeing across the lifecourse, and determine the effect of these on the receipt of hospital care. The findings will provide evidence for the development of clinical interventions to reduce sarcopenia and frailty and improve the health and quality of life of older people.