Prognostic potential of neutrophil-to-lymphocyte ratio for appendicular skeletal muscle mass reduction in males aged 70 and older.

Inflammation plays a pivotal role in the age-related decline of skeletal muscle mass, leading to sarcopenia in the elderly. The prevalence of sarcopenia notably increases among males aged ≥ 70. However, it remains unclear whether inflammatory indexes are associated with the reduction in skeletal muscle mass in the elderly population. Thirty-one males aged ≥ 70, without severe diseases or dementia, were enrolled in the study. They underwent muscle mass measurements, physical measurements, and hematological tests at the onset of the study and after a one-year follow-up. Twenty-eight participants were successfully followed for one year. Appendicular skeletal muscle mass index (ASMI) decreased by 3.30 ± 2.41% in 14 participants and increased by 2.66 ± 1.61% in the other 14 participants compared to baseline levels. The baseline neutrophil-to-lymphocyte ratio (NLR) was 2.14 ± 0.56 in the ASMI-decreased group and 1.66 ± 0.62 in the ASMI-increased group. A statistically significant negative correlation was found between baseline NLR and the change in ASMI in linear regression analyses. The area under the curve (AUC) of the baseline NLR for predicting ASMI decline was 0.724, with an optimal sensitivity of 64.3% and specificity of 78.6% at a cut-off value of 1.94. NLR emerged as a potential prognostic marker for ASMI reduction in elderly males. However, further studies are necessary to assess its clinical utility.