Factors Associated with Postoperative Skeletal Muscle Loss during Hospitalization in Patients with Non-Small Cell...

Postoperative skeletal muscle mass tends to decrease early, potentially affecting long-term prognosis and physical function. This study aimed to assess the extent of and factors associated with postoperative skeletal muscle loss (PSML) occurring during hospitalization in patients with non-small cell lung cancer (NSCLC) who were undergoing lobectomy.

This retrospective cohort study included patients who underwent lobectomy for NSCLC. The extent of PSML during hospitalization-defined as the skeletal muscle mass index (SMI) loss rate [(preoperative SMI - SMI before discharge) / preoperative SMI × 100]-was evaluated along with associated factors, including patient background, rehabilitation assessments, surgical parameters, and postoperative course variables.

The cohort comprised 185 patients with a median age of 71.0 years (66.0-76.0), and 103 patients (55.7%) were male. The median SMI loss rate was 4.2%. Factors significantly associated with the SMI loss rate included female sex (B = 2.48; 95% confidence interval [CI]: 0.41-4.54; p = 0.018), body mass index (BMI) (B = 0.23; 95% CI: 0.07-0.38; p = 0.005), preoperative extracellular water-to-total body water ratio (ECW/TBW) (B = 223.80; 95% CI: 112.02-335.58; p < 0.001), difficulty completing three full meals per day by the fourth postoperative day (B = 1.69; 95% CI: 0.26-3.11; p = 0.020), and postoperative length of stay (B = 0.29; 95% CI: 0.06-0.52; p = 0.013).

Patients with NSCLC who underwent lobectomy experienced a median PSML of 4.2% during hospitalization. PSML was more likely to occur in female patients and in patients with higher BMI, higher preoperative ECW/TBW, difficulty completing full meals by the fourth postoperative day, and longer postoperative length of stay. Preventive strategies against PSML in patients with NSCLC should emphasize perioperative management and rehabilitation tailored to individual patient characteristics.