SARCOPENIA, SARCOPENIC OBESITY AND FRAILTY; LINKS TO COGNITIVE PERFORMANCE IN ELDERS: Session 412

Abstract

Background: According to 2011 CDC data, more than 2.6 million adults aged 60 and older with cognitive impairment reported difficulty performing one or more ADLs. There are studies that link cognitive decline and physical impairment in terms of low-level chronic inflammation, oxidative stress, and depression. Skeletal muscle can produce IL-1, IL-6 and other important myokines that have been implicated in cognitive and physical functional degenerative processes. Oxidative stressors have been linked to physical frailty and sarcopenia as well as neurodegenerative processes further worsening cognitive impairment. What are Sarcopenia and Sarcopenic Obesity and its impacts on elders? Sarcopenia is a primary disease of the elderly population, characterized by loss of skeletal muscle mass and function. Sarcopenia is correlated with physical disability, poor quality of life, frailty, cognitive impairment, and death. Age, gender, and level of physical activity are the risk factors for the Sarcopenia. In addition to aging, malignancy and rheumatoid arthritis causes loss of lean body mass and even increase in body fat mass. The loss of muscle mass associated with increased body fat mass i.e. sarcopenic obesity causes weakness in aging. Sarcopenia, with or without obesity, results in impairment of IADL (Instrumental Activity of Daily Living) and eventually ADLs (Activities of Daily Living) among elders and results in need for long-term care and increased cost of health care. What is the link between Sarcopenia and Cognitive Impairment? Sarcopenia has not only has a greater effect on survival but also on cognitive impairment. Sarcopenia has been linked to global cognitive impairment and dysfunction in specific cognitive skills including memory, speed, and executive functions. While obesity may impair the executive functions of aging, the exact mechanism linking obesity to cognitive dysfunction is not clear. Improvement in muscular function of obese older adults has been linked to improvement of executive functions. Obesity and Sarcopenia were associated with the lower executive function such as working memory, mental flexibility, self-control and orientation when assessed independently and even more so when they occurred together. Sarcopenia is highly correlated with frailty and risk of falls in elders; it also represents an important risk factor for disability and mortality. Frailty is an independent predictor of dementia. How do you assess for the Sarcopenia? Sarcopenia with or without obesity can be used in clinical practice to assess the potential risk of cognitive impairment in elders. There are several ways to measure Sarcopenia – DEXA (Dual-Energy X-ray Absorptiometry), biometric impedance analysis (BIA), CT (Computed Tomography) scan and MRI (Magnetic Resonance Imaging). However, assessing BMI and testing grip strength by dynamometry can be easily administered during annual wellness visits to assess the risk of sarcopenic related cognitive impairments. Sarcopenia can be assessed using parameters such as 1) Measure walking speed in elderly (>65 years). If the walking speed is below 0.8 m/s at the 4-m walking test, measure the muscle mass. 2) Hand- grip strength if this value is lower than 20kg in women and 30kg in man then muscle mass must be analyzed. 3) Defining Fat mass and lean body mass using BIA 4) Muscle Mass assessment by DEXA or CT. What is the significance of assessing the Sarcopenia? It is important to identify the risk of cognitive impairment by assessing for the onset of this condition. Preventing or delaying onset will likely enhance survival and reduce the demand for long-term care. Increasing resistance physical training will help to improve physical deconditioning, strengthen skeletal muscle hypertrophy, overcome the pain syndrome and enhance overall mental well-being. Interventions such as resistance exercise and nutritional therapy need to be developed specifically to delay the onset of Sarcopenia. What is the need in the future? Team-based approach including multidisciplinary model involving primary care physicians, geriatric psychiatrists, pain management physicians and physical therapists is required to combat the complex interlinked Sarcopenia associated cognitive impairment. Screening programs that include identification of cognitive and functional impairment in the office setting will serve as the starting point for specific interventions. The training regimen that includes supervision and correct equipment with resistance exercise will be necessary to get proper training and delay the muscle loss in elderly.