Screening for Sarcopenia (Physical Frailty) in the COVID-19 Era

Abstract

Although the numbers of aged populations have risen considerably in the last few decades, the current coronavirus disease 2019 (COVID-19) has revealed an extensive vulnerability among these populations. Sarcopenia is an age-related disorder that increases hospitalization, dependencies, and mortality in older adults. It starts to develop in midlife or even earlier as a result of unbalanced diet/poor nutrition and low levels of physical activity, in addition to chronic disorders such as obesity and diabetes mellitus. Given that social isolation is adopted as the most protective measure against COVID-19, the level of physical activity and the intake of adequate diet have considerably declined, especially among older adults—denoting an increased possibility for developing sarcopenia. Research also shows a higher vulnerability of sarcopenic people to COVID-19 as well as the development of wasting disorders such as sarcopenia and cachexia in a considerable proportion of symptomatic and recovering COVID-19 patients. Muscular wasting in COVID-19 is associated with poor prognosis. Accordingly, early detection and proper management of sarcopenia and wasting conditions in older adults and COVID-19 patients may minimize morbidity and mortality during the current COVID-19 crisis. This review explored different aspects of screening for sarcopenia, stressing their relevance to the detection of altered muscular structure and performance in patients with COVID-19. Current guidelines recommend prior evaluation of muscle strength by simple measures such as grip strength to identify individuals with proven weakness who then would be screened for muscle mass loss. The latter is best measured by MRI and CT. However, due to the high cost and radiation risk entailed by these techniques, other simpler and cheaper techniques such as DXA and ultrasound are given preference. Muscle loss in COVID-19 patients was measured during the acute phase by CT scanning of the pectoralis muscle simultaneously during a routine check for lung fibrosis, which seems to be an efficient evaluation of sarcopenia among those patients with no additional cost. In recovering patients, muscle strength and physical performance have been evaluated by electromyography and traditional tests such as the six-minute walk test. Effective preventive and therapeutic interventions are necessary in order to prevent muscle loss and associated physical decline in COVID-19 patients.

Physical Frailty/Sarcopenia as a Key Predisposing Factor to Coronavirus Disease 2019 (COVID-19) and Its Complications in Older Adults

“…It plays a major role in core bodily processes such as breathing, bone and neuromuscular function, gait maintenance, and locomotion [33,35]. Skeletal muscle comprises multiple tissue structures including myofibers or multinucleated cells-the main contributor to muscle quantitative and qualitative properties-neurons, connective tissues, and vasculature networks [11,36]. A single human muscle may contain different proportions of fiber types [37].…”

“…Poor muscle mass and strength negatively correlate with the respiratory muscle strength, which is reflected by maximum expiratory pressure [65]. Therefore, sarcopenia may exacerbate pulmonary function in older COVID-19 patients [36,66]. Furthermore, longitudinal data denote that low skeletal mass and sarcopenic obesity are associated with an increased risk for renal injury-indicated by developing albuminuria [67].…”

“…Moreover, frailty is a key predictive factor for poor prognosis and mortality in patients with COVID-19 [28,29]. It is suggested that the use of frailty as a predictor of poor prognosis can be more informative than the use of age or comorbidities for this purpose because frailty in COVID-19 has been also noted in young individuals [31,32,36,66]. In this regard, elders with higher Frailty Index (FI) are at high risk for intensive care unit (ICU) admission [31].…”

“…Physical activity is a key factor that affects physiological processes within the entire body including those involved in maintaining the shape and structure of muscle fibers [36,106]. Evidence denotes that biological aging of human skeletal muscle is not necessarily related to chronological aging-loss of muscle mass can start as early as the second decade of life, and it is exacerbated by muscle inactivity associated with a sedentary lifestyle [2,3,15].…”

Vitamin K in COVID-19—Potential Anti-COVID-19 Properties of Fermented Milk Fortified with Bee Honey as a Natural Source of Vitamin K and Probiotics

“…Protein degradation in severe COVID-19 infections contributes to inflammation, which affects different body structures, including skeletal muscle proteins leading to weakness, muscle aches, and fatigue. The latter is the third most common symptom in symptomatic patients [25,26,31,137]. In severe cases, hypoproteinemia boosts multiple organ failure and mortality [25,26,28].…”