To the best of our knowledge, this is the first study to evaluate the relationship between the combination of PMI and PMD and mortality in patients undergoing hemodialysis.įull size table Agreements for the PMA and PMD measurements We also examined whether the combination of PMI and PMD could improve prediction of mortality in this population. Thus, this study aimed to investigate the associations between CT-measured PMI and PMD and all-cause mortality in patients undergoing hemodialysis. We hypothesized that myosteatosis could be a novel predictor in this population and that the combination of PMI and PMD, which may reflect muscle quantity and muscle quality, respectively, may improve the accuracy of mortality prediction in this population. The association between muscle quality and mortality has never been investigated in patients undergoing hemodialysis. CT-measured psoas muscle density (PMD), which measures the average Hounsfield Unit (HU) attenuation of the bilateral psoas muscles, is a promising predictor of mortality in patients with various cancers, type 2 diabetes mellitus, and trauma 16, 17, 18, 19. Regarding muscle quality, the CT attenuation value of the abdominal skeletal or psoas muscles is used as a surrogate marker of myosteatosis, defined as increased fat infiltration in the skeletal muscle 11. In patients undergoing hemodialysis, PMI may reflect the whole-body skeletal muscle mass and predict mortality 14, 15. The former include abdominal skeletal muscle index and psoas muscle index (PMI), in which the area of each muscle is adjusted by the square of the height at the level of the third lumbar vertebra (元). Regarding muscle quantity, CT-measured sarcopenic indices are widely used to diagnose sarcopenia or muscle wasting, and to predict mortality in patients with various cancers or chronic liver disease 11. The importance of evaluating both muscle quantity and quality using CT was recently proposed 11, 12, 13. We have previously reported that the CT-measured psoas muscle thickness normalized by height, an easily available surrogate marker of muscle mass volume, may be an indicator of PEW and a promising predictor of mortality in patients undergoing hemodialysis 6. However, the use of CT for evaluating body composition is now limited because of its high cost and the radiation exposure associated with this procedure. Thus, computed tomography (CT), which is not affected by hydration status, is the gold standard method to estimate muscle mass in patients undergoing hemodialysis 10. Although dual-energy X-ray absorptiometry and bioelectrical impedance analysis are clinically available to estimate muscle mass hydration status affects the accuracy of these methods 8, 9. In patients undergoing hemodialysis, muscle function, muscle strength, and physical performance that are core elements for a sarcopenia diagnosis are usually low therefore, the precise measurement of muscle mass is important 7. Thus, muscle wasting may partially explain PEW. Protein energy wasting (PEW), a malnutrition state characterized by loss of muscle and fat mass due to chronic inflammation, is also highly prevalent among patients undergoing hemodialysis and is associated with an increased risk of mortality 3, 4, 5, 6. It may be caused by protein imbalance secondary to inflammation, increased protein catabolism, and insufficient calorie and protein intakes 2. Muscle wasting commonly occurs in patients with end-stage renal disease undergoing hemodialysis and is associated with significant morbidity and mortality 1, 2. The combination of PMI and PMD may improve mortality prediction in patients undergoing hemodialysis. The addition of PMI and PMD to the risk model significantly improved C-index from 0.775 to 0.893 (p < 0.00001). Lower PMI and lower PMD were independently associated with an increased risk of all-cause mortality. During follow-up (median 3.5 years), 69 patients died. The optimal cut-off values of PMI and PMD for men and women were 3.39 cm 2/m 2 and 41.6 HU, and 2.13 cm 2/m 2 and 37.5 HU, respectively. We found that PMI and PMD were independently associated with the geriatric nutritional risk index and log C-reactive protein, respectively. PMI and PMD were measured at the third lumbar vertebral level. We included 188 hemodialysis patients who underwent abdominal CT. This study aimed to investigate the associations of computed tomography (CT)-measured psoas muscle index (PMI: psoas muscle area normalized by height) and psoas muscle density (PMD: average of bilateral psoas muscle CT values ) with mortality in patients undergoing hemodialysis.
0 Comments
Leave a Reply. |