Individuals with sarcopenia have an increased risk of frailty. Among the critically ill population, about 40% have sarcopenia and up to 30% have frailty.² Both sarcopenia and frailty are associated with an age-related decline in multiple biological systems. For example, they are reported to worsen the clinical outcomes for major cardiac diseases including heart failure and coronary artery disease.^3,4 Like sarcopenia, frailty is associated with increased mortality and morbidity, including a greater risk of falls and fractures, impaired mobility, loss of independence, and decreased quality of life.^5,6 

Frailty is a multi-dimensional syndrome where the individual has a greater vulnerability to everyday stressors, making them more likely to become dependent on a caretaker and/or experience adverse health outcomes.^5,7 Frailty can manifest physically, psychosocially, or as a combination of both, and is a dynamic state that can either improve or deteriorate over time.⁸ According to the Fried Frailty Index, physical manifestations of frailty include three or more of the following five outcomes: low grip strength, slow walking (gait) speed, self-reported exhaustion, decreased physical activity and/or unintentional weight loss (>4.5 kg in a year).^2,5,9 Psychosocial effects of frailty include a decreased desire to socialize or engage in physical activity, increased risk of depression, increased risk of delirium, and reduced self-reported life satisfaction.^2,10

Sarcopenia and frailty are compounded with extended hospital stay. A review of six studies including over 100,000 patients determined that frailty was a significant predictor of fractures among elders in community homes.¹¹ Many of these individuals are bedridden, which creates a negative feedback loop where limited mobility decreases their muscle mass, gradually making them weaker and making it more challenging for them to regain muscle. Additionally, regardless of age, people in the intensive care unit (ICU) lose muscle mass within the first week of their admission, and these effects can last up to five years after being discharged.^2,12 As there are no pharmaceutical interventions to reverse muscle loss or maintain muscle, the only approaches to combat the decrease in muscle function are exercise and nutrition.² However, the amount of exercise needed to maintain muscle tone and physical function may be more than what an ICU or critical care patient can sustain. Another challenge is meeting the necessary protein and nutrient requirements to grow muscle, which may not always be feasible with hospital meals alone.

The relationship between sarcopenia and frailty cannot be overstated, as they are critical in shaping health outcomes. Most studies on frailty and sarcopenia are described in the context of elderly individuals, but the importance of maintaining muscle mass and function while in the hospital setting holds true for people of all ages. No one is immune to muscle loss during long-term bed rest, and there is no gold standard for the treatment of sarcopenia and frailty.⁷ Therefore, clinical developments to mitigate muscle loss and improve muscle function are necessary to combat frailty and promote a healthy lifespan.