Tehran University Medical Journal

Life expectancy has increased throughout the world and, as a result, the population of the elderly is also rising. From the age of 30 years old, the human body mass loses about 0.1 to 0.5% of its skeletal muscle mass annually, which is accelerated after the age of 65 years old. Aging is characterized by a decrease in the progression of musculoskeletal and physical activity known as sarcopenia. Sarcopenia has a complex molecular pathogenesis that includes age-related changes in muscles’ neuromuscular activity, muscle protein replacement, the hormone levels and the related sensitivity of human body to these mentioned factors. The pathogenic conditions and other disorders in sarcopenia are the chronic inflammatory states that include oxidative stress and changes in behavioral factors, especially in nutritional status and physical activity. By definition of the European Working Group on Sarcopenia in Older People (EWGSOP), the diagnosis of sarcopenia is determined by the presence of two main factors which are low muscle mass and low muscle function. Besides, specific sarcopenia-related biomarkers have been identified for early diagnosis and accurate identification of the main pathophysiology mechanisms involved in the development of the disease. Since sarcopenia has adverse outcomes on public health in terms of behavioral factors, frailty, hospitalization and mortality of people, it is an important necessity for the social health system to plan some therapeutic approaches to prevention. The main and more important of these therapeutic approaches have known as exercises, nutritional supplements and hormonal therapies. Also, other new therapeutic strategies are under investigation to be introduced in the future. However, currently, it has been shown that only physical exercise has a positive effect on the controlling and prevention of sarcopenia and its adverse effects on human and public health. However, the role of appropriate nutrition is also effective. Therefore, carefully designed studies in terms of better utilization of physical activity are needed to achieve useful therapeutic results for sarcopenia management. Thus, this survey aims to review the other considerable studies on the pathogenesis, appropriate evaluation of the disease and treatment options for sarcopenia.

Background: Sarcopenia is the degenerative loss of skeletal muscle mass, which is known as a poor postoperative outcome in various cancer types. Radical cystectomy (RC) is often associated with high mortality rates, and sarcopenia is hypothesized to aid in risk stratification. Hence, this study assessed the role of Sarcopenia as an indicator of postoperative outcomes and survival rates in patients undergoing RC for bladder cancer.
Methods: This cross-sectional research was carried out between January 2022 and January 2023 on 30 patients with bladder cancer who were candidates for RC and referred to the urology clinic of Imam Khomeini Hospital in Tehran. One week before surgery, the cross-sectional area of the psoas muscle was measured using MRI to estimate muscle volume, and the sarcopenia index was calculated. Muscle area evaluation was performed by calculating the cross-sectional area of the left and right psoas muscles on MRI. The psoas muscle area was calculated by excluding blood vessels, bony structures, and intermuscular fat regions based on fat signals. The calculated psoas muscle area was then normalized to the patient's height in square meters. To improve the quality of reporting on surgical complications, the patients were re-examined and the duration of patients' hospital stays was measured.
Results: The mean sarcopenic index for the patients was 1264.6 ± 591.5 mm²/m². Seven patients (24.1%) were smokers, while 22 patients (75.9%) were non-smokers. During the 10-month follow-up period, 25 patients (83.3%) remained alive, and 5 patients (16.7%) passed away. The mean value of sarcopenic index in patients with localized cancer was higher than those with advanced cancer, but this difference was not statistically significant. Data analysis revealed a significant association between higher mortality rates and the presence of locally advanced bladder tumors (P = 0.046). Additionally, a reduced sarcopenic index in this study was significantly correlated with lymphovascular invasion. In this study, no correlation was found between perioperative complications and sarcopenic index.
Conclusion: To conclude, a significant association was observed between a reduction in the sarcopenic index and lymphovascular invasion; however, no connection was identified between mortality rates and postoperative complications following RC.