Sarcopenic obesity by the ESPEN/EASO criteria for predicting mortality in advanced non-small cell lung cancer

The European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity (EASO) recently released the first international consensus on the diagnostic criteria for sarcopenic obesity (SO), which recommended skeletal muscle mass adjusted for body weight (SMM/W) to determine low muscle mass. SMM adjusted for body mass index (SMM/BMI) appeared to be better associated with physical performance than SMM/W. Thus, we modified the ESPEN/EASO criteria by using SMM/BMI. We aimed (1) to evaluate the agreement of the ESPEN/EASO-defined SO (SO_ESPEN) and the modified ESPEN/EASO-defined SO (SO_ESPEN-M) with other commonly used SO definitions, and (2) to compare different SO definitions for predicting mortality in a prospective cohort with advanced non-small cell lung cancer (NSCLC).

This prospective study included patients with advanced NSCLC. We defined SO according to five different diagnostic criteria: SO_ESPEN, SO_ESPEN-M, Asian Working Group for Sarcopenia (AWGS)-determined sarcopenia with BMI-determined obesity (SO_AWGS), computed tomography-derived sarcopenia with BMI-determined obesity (SO_CT), and fat mass to fat-free mass ratio >0.8 (SO_FM). The outcome was all-cause mortality.

Of the 639 participants (mean age 58.6 years, 229 women) we studied, 488 (76.4%) died during the median follow-up period of 25 months. SMM/BMI was significantly lower in the death group than in the survivor group (men: p = 0.001, women: p < 0.001), but SMM/W was not. Only 3 (0.47%) participants met all five SO diagnostic criteria. SO_ESPEN showed an excellent agreement with SO_ESPEN-M (Cohen's kappa = 0.896), a moderate agreement with SO_AWGS (Cohen's kappa = 0.415), but poor agreements with SO_CT and SO_FM (Cohen's kappa = 0.078 and 0.092, respectively). After full adjustment for potential confounders, SO_ESPEN (HR 1.54, 95% CI 1.26-1.89), SO_ESPEN-M (HR 1.56, 95% CI 1.26-1.92), and SO_AWGS (HR 1.43, 95% CI 1.14-1.78) were significantly associated with mortality. However, SO_CT (HR 1.17, 95% CI 0.87-1.58) and SO_FM (HR 1.15, 95% CI 0.90-1.46) showed no significant association with mortality.

SO_ESPEN showed an excellent agreement with SO_ESPEN-M, a moderate agreement with SO_AWGS, but poor agreements with SO_CT and SO_FM. SO_ESPEN, SO_ESPEN-M, and SO_AWGS were independent prognostic factors for mortality in our study population, but SO_CT and SO_FM were not. Although SMM/BMI was better associated with survival than SMM/W, SO_ESPEN-M did not show an advantage in predicting survival over SO_ESPEN.