ISRA May 2022

Sarcopenia as an Indicator of Negative Outcomes in Kidney Transplant Patients

Hila Yashar 1 Ido Druckmann 1 Roie Tzadok 2 Ayelet Grupper 2
1Radiology Department, Tel Aviv Sourasky Medical Center, Israel
2Nephrology Department, Tel Aviv Sourasky Medical Center, Israel

Purpose: Preoperative risk assessment for kidney transplantation is largely subjective. Better measures of kidney transplant risk stratification are needed. Sarcopenia (muscle loss) has been explored as an objective measure for patient frailty in high morbidity procedures such as liver transplantation. Our study investigated the impact of sarcopenia on patients undergoing kidney transplantation. The goal was to explore whether differences in muscle loss groups can predict different outcomes post-transplantation.

Methods: A retrospective analysis was performed. Our study population included 97 kidney transplant recipients with preoperative non-contrast CT scan. Sarcopenia was assessed by measuring total psoas muscle area (TPA) and Hounsfield unit (HU) average at the L3 vertebral level. The measurement was performed manually by the same radiologist using the PACS area drawing tool, measuring both right and left psoas muscles.

Results: The median age at transplantation was 56.6 years (range 22.1-77.8), and most patients were male (64, 66%). The lowest TPA quartile (sarcopenia) was significantly related to older age (OR=1.2 (IQR 1.01-1.44), p=0.03) and male gender (1.9 (1.3-2.9) p=0.03), while negatively associated with BMI (0.63 (0.39-0.99) p=0.03).

The lowest HU quartile (sarcopenia) was significantly associated with older age (1.34 (1.06-1.67) p=0.02), and pre-transplantation diabetes (1.98 (1.2-3.1) p=0.04).

Lowest TPA and HU quartiles were associated with an increased risk of death following transplantation (p=0.05, 0.03 respectively). Lowest HU quartile was significantly associated with inferior kidney graft function as measured by serum creatinine, compared with other quartiles (2.3±1.9 vs 1.4 ±1.0 mg/dl, p=0.043, respectively).

Conclusion: Our study showed that total psoas area (TPA) and Hounsfield Units (HU) average are significant parameters of sarcopenia that can help identify patients at risk before kidney transplantation. Identifying objective measures of preoperative risk is important for improving the care of kidney transplant patients. These findings can aid in predicting post-transplant outcomes and assist in clinical decision making.