CT-Defined Low Skeletal Muscle Mass Predicts Early Swallowing and Quality-of-Life Recovery After Head-and-Neck...

Background and objectives: Early recovery after major head-and-neck reconstruction is shaped by nutritional vulnerability and functional decline. We evaluated whether preoperative CT-defined low skeletal muscle mass-considered here as an imaging-derived muscle-depletion phenotype rather than the full consensus syndrome of sarcopenia-predicts swallowing milestones, weight trajectory, and patient-reported outcomes at 12 weeks. Methods: In a prospective longitudinal cohort of 74 adults undergoing oncologic resection with reconstruction, low skeletal muscle mass was derived from preoperative cervical CT-based skeletal muscle measurements and nutritional risk was screened with NRS-2002. Outcomes included FOIS, PEG dependence, percent weight loss, MDADI, and European Organisation for Research and Treatment of Cancer QLQ-C30/QLQ-H&N35 at 12 weeks. A multivariable logistic regression explored a composite poor-recovery endpoint (PEG at 12 weeks and/or FOIS ≤ 3 and/or MDADI < 55). Results: Low skeletal muscle mass (32/74, 43.2%) was associated with longer length of stay (13.4 ± 4.1 vs. 10.3 ± 3.3 days; p < 0.001) and more major complications (31.2% vs. 11.9%; p = 0.04). At 12 weeks, affected patients had greater weight loss (10.9 ± 3.4% vs. 8.6 ± 2.6%; p = 0.003), lower FOIS (3.9 ± 1.1 vs. 4.6 ± 1.1; p = 0.01), lower MDADI (57.1 ± 10.9 vs. 66.6 ± 11.9; p = 0.001), and higher PEG dependence (31.2% vs. 9.5%; p = 0.018). Low skeletal muscle mass remained associated with poor recovery after adjustment (aOR 5.4; 95% CI 1.4-24.0; p = 0.016); adjuvant radiotherapy was also associated (aOR 4.3; p = 0.049). Model discrimination was good (AUC 0.81). Conclusions: Preoperative CT-defined low skeletal muscle mass was associated with impaired early recovery after major head-and-neck reconstruction, particularly when adjuvant radiotherapy was anticipated; however, these findings should be interpreted as exploratory and hypothesis-generating.