Objective: Osteoporosis is prevalent in patients with chronic kidney disease (CKD), with risk increasing as CKD progresses, subsequently elevating fracture risk. While previous studies have shown a link between low skeletal muscle mass and osteoporosis in the general population, there is limited research exploring this relationship in patients with advanced CKD (stages 3-5D). This study aimed to evaluate whether skeletal muscle area (SMA), as measured by abdominal CT, is correlated with bone mineral density (BMD) in advanced CKD patients beginning hemodialysis. Methods: This single-center, retrospective cohort study included patients who started maintenance hemodialysis at Daejeon St. Mary’s Hospital from January 2018 to September 2021. Patients who underwent abdominal CT and BMD assessments within three months of dialysis initiation were enrolled, resulting in a sample of 87 individuals. Baseline characteristics were analyzed, with patients stratified by sex and SMA quartiles. Pearson’s correlation and multivariate regression analyses were conducted to the relationship between SMA and BMD T-scores. Results: The study cohort had an average age of 65.4 years, with 52.9% of participants being male. Male patients exhibited significantly higher SMA and BMD T-scores in both the lumbar spine and femur compared to female patients. SMA showed the strongest positive correlation with BMD at both sites (lumbar spine, r = 0.424; femur, r = 0.514; p < 0.001). Multivariate analysis identified SMA as an independent positive predictor of BMD, while alkaline phosphatase (ALP) was independently associated with lower femur BMD. In the SMA-based subgroup analysis, patients with lower SMA had significantly lower BMD T-scores and a higher risk of osteoporosis. Logistic regression indicated that patients in the lowest SMA quartile had substantially increased odds of osteoporosis compared to those in the highest quartile, with an adjusted odds ratio of 30.59 (p = 0.008). Conclusions: Lower skeletal muscle mass is significantly associated with lower bone density and a higher risk of osteoporosis in advanced CKD patients initiating hemodialysis. SMA, as measured by abdominal CT, may serve as a useful marker for identifying patients at elevated osteoporosis risk in this population.

Pure red cell aplasia (PRCA) is a rare blood disorder characterized by the selective absence of erythroblasts in an otherwise normal bone marrow, leading t

Renal lipotoxicity and oxidative stress are major contributors to diabetic kidney disease (DKD), but the role of proprotein convertase subtilisin/kexin type 9 (PCSK9) and its relationship with AMP-activated protein kinase (AMPK) signaling remain unclear. We investigated the effects of PCSK9 inhibition on renal lipotoxicity and oxidative stress in db/db mice and high-glucose (HG)-treated HK-2 cells using a selective PCSK9 inhibitor (PCSK9i) with or without AMPKα1/α2 small interfering RNA (siRNA). PCSK9i significantly reduced albuminuria, renal injury, histopathological changes, and intrarenal lipid accumulation without altering glycemic control. These effects were accompanied by increased low-density lipoprotein receptor (LDLR) expression, reduced cluster of differentiation 36 (CD36) expression, enhanced AMPK phosphorylation and peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) expression, reduced sterol regulatory element-binding protein-1c (SREBP-1c) expression, restored carnitine palmitoyltransferase 1 (CPT1) expression, modulated protein kinase B (Akt)/forkhead box O (FoxO) signaling, and reduced oxidative stress and apoptosis. Similar findings were observed in HG-treated HK-2 cells. Importantly, AMPK knockdown attenuated the protective effects of PCSK9i on lipid metabolism, oxidative stress, and apoptosis in HK-2 cells. PCSK9 inhibition attenuates renal lipotoxicity and oxidative stress in DKD, providing a preclinical rationale for further investigation of the renal metabolic effects of PCSK9-directed therapies and their association with AMPK activation.