From the Guidelines
Sarcopenic obesity is a significant and independent risk factor for increased morbidity, mortality, and reduced quality of life due to its strong association with cardiovascular disease, as evidenced by the most recent and highest quality study published in 2021 1.
Definition and Prevalence
Sarcopenic obesity refers to the state of decreased muscle mass in the setting of increased fat mass, creating a unique clinical challenge due to the difficulty in detecting muscle wasting without dedicated testing, as fat mass can mask underlying muscle loss 1. The prevalence of sarcopenic obesity in patients with cirrhosis ranges from 20% to 35%, with non-alcoholic fatty liver disease (NAFLD) being a strong risk factor for sarcopenic obesity, even after adjustment for metabolic comorbidities 1.
Pathophysiology and Cardiovascular Risks
The coexistence of low muscle mass and excess fat tissue in sarcopenic obesity leads to increased systemic inflammation, with adipose tissue releasing pro-inflammatory cytokines while reduced muscle mass diminishes anti-inflammatory myokines. This condition promotes insulin resistance, as skeletal muscle is the primary site for glucose disposal, and its reduction alongside increased adiposity creates a perfect storm for metabolic dysfunction. Patients with sarcopenic obesity typically exhibit dyslipidemia with elevated triglycerides and reduced HDL cholesterol, alongside hypertension partly driven by increased sympathetic nervous system activity and renin-angiotensin-aldosterone system activation. These factors substantially increase the risk of atherosclerosis, coronary artery disease, heart failure, and stroke.
Management Strategies
Management of sarcopenic obesity should focus on combined strategies addressing both components:
- Resistance training to build muscle mass
- Aerobic exercise
- Dietary interventions targeting weight loss while ensuring adequate protein intake (1.2-1.5g/kg/day) to preserve muscle Medications like metformin may help address insulin resistance, while statins and antihypertensives should be considered based on individual risk profiles. The importance of addressing obesity and sarcopenia is highlighted by the American Heart Association, emphasizing that weight loss and physical activity can prevent and treat obesity-related coronary heart disease risk factors and should be considered a primary therapy for obese patients with cardiovascular disease 1.
Clinical Implications
Given the rising prevalence of obesity-related liver diseases and the association between obesity and muscle loss in patients with cirrhosis, it is crucial to recognize sarcopenic obesity as a significant risk factor for cardiovascular disease. The combination of primary (aging-related) and secondary (chronic disease–related) sarcopenia, referred to as “compound sarcopenia,” occurs in older adults with cirrhosis and is associated with higher odds of death and greater resource use 1. Therefore, early detection and management of sarcopenic obesity are critical to reducing cardiovascular risks and improving outcomes in affected individuals.
From the Research
Definition and Prevalence of Sarcopenic Obesity
- Sarcopenic obesity (SO) is a condition characterized by the simultaneous presence of sarcopenia and obesity, with a increasing prevalence in adults over 65 years of age 2.
- The coexistence of excess fat mass and reduced skeletal muscle mass and strength in SO exacerbates cardiometabolic risk and adverse health outcomes beyond either condition alone 3.
Cardiovascular Risks Associated with Sarcopenic Obesity
- SO has emerged as an important cardiovascular risk factor, particularly in older adults, with growing evidence suggesting it exacerbates cardiometabolic risk and adverse health outcomes 3.
- The heterogeneity in diagnostic criteria and the observational nature of most studies prohibit the evaluation of a causal relationship between SO and cardiovascular disease 3.
Exercise Interventions for Sarcopenic Obesity
- Exercise interventions, such as resistance training, aerobic exercise, and combined exercise, have been shown to be effective in improving physical performance and reducing the risk of chronic diseases in adults with SO 4, 5, 6.
- Resistance training has been found to improve gait speed and lower leg strength in individuals with SO, while combined exercise can achieve both fat mass reduction and skeletal muscle mass and strength increase 4, 6.
Lifestyle Therapy and Management of Sarcopenic Obesity
- Lifestyle therapy, including physical activity and correct nutritional treatment, has been shown to be effective in the regression of SO and improvement of physical function 2.
- Current management of SO revolves around diet for weight loss coupled with resistance training to mitigate further muscle loss, with emerging pharmacologic therapies showing promising results 3.