Associations of pre‐existing co‐morbidities with skeletal muscle mass and radiodensity in patients with non‐metastatic colorectal cancer

Abstract

Background and aimCo‐morbidities and computerized tomography‐measured muscle abnormalities are both common in cancer patients and independently adversely influence clinical outcomes. Muscle abnormalities are also evident in other diseases, such as diabetes and obesity. This study examined for the first time the association between co‐morbidities and muscle abnormalities in patients diagnosed with colorectal cancer (CRC).MethodsThis cross‐sectional study included 3051 non‐metastatic patients with Stages I–III CRC. Muscle abnormalities, measured at diagnosis, were defined as low skeletal muscle mass index (SMI) or low skeletal muscle radiodensity (SMD) quantified using computerized tomography images using optimal stratification. Co‐morbidities included in the Charlson index were ascertained. χ2 tests were used to compare the prevalence of co‐morbidities by the presence or absence of each muscle abnormality. Logistic regressions were performed to evaluate which co‐morbidities predicted muscle abnormalities adjusting for age, sex, body mass index, weight change, cancer stage, cancer site, race/ethnicity, and smoking.ResultsMean age was 63 years; 50% of patients were male. The prevalence of low SMI and low SMD were 43.1% and 30.2%, respectively. Co‐morbidities examined were more prevalent in patients with low SMD than in those with normal SMD, and most remained independent predictors of low SMD after adjustment for covariates. Co‐morbidities associated with higher odds of low SMD included myocardial infarction [odds ratio (OR) = 1.77, P = 0.023], congestive heart failure (OR = 3.27, P < 0.001), peripheral vascular disease (OR = 2.15, P = 0.002), diabetes with or without complications (OR = 1.61, P = 0.008; OR = 1.46, P = 0.003, respectively), and renal disease (OR = 2.21, P < 0.001). By contrast, only diabetes with complications was associated with lower odds of low SMI (OR = 0.64, P = 0.007).ConclusionsPrevalence of muscle abnormalities was high in patients with non‐metastatic CRC. Pre‐existing co‐morbidities were associated with low SMD, suggestive of a potential shared mechanism between fat infiltration into muscle and each of these co‐morbidities.

The relationship between computed tomography‐derived body composition, systemic inflammatory response, and survival in patients undergoing surgery for colorectal cancer

“…Indeed, it was of interest that in the present study, ASA was significantly associated with SMD and not SMI. A similar relationship has recently been reported between SMD but not SMI and the Charleston co‐morbidity index . This confirms the clinical utility of SMD as there is increasing recognition that an increase in muscle mass is not necessarily associated with an increase in function .…”

“…A similar relationship has recently been reported between SMD but not SMI and the Charleston co-morbidity index. 26 This confirms the clinical utility of SMD as there is increasing recognition that an increase in muscle mass is not necessarily associated with an increase in function. 34,35 It may be that an improvement in muscle quality rather than mass will result in an improvement in physical function.…”

“…29 6 In contrast, Xiao et al in 3051 nonmetastatic stage I-III CRC defined myosteatosis according to sex as <35.5 HU in men and <32.5 HU in women. 26 In the present study, SMD (Dolan) thresholds were derived using receiver operating characteristic curve analysis to determine thresholds associated with overall survival in this population. This was also conducted using validated online biomarker cut-off optimization software.…”

“…Myosteatosis was also defined by Xiao et al . as <35.5 HU in men and <32.5 HU in women . Subcutaneous fat index was defined as ≥50.0 cm 2 /m 2 in men and ≥42.0 cm 2 /m 2 in women ( Table ).…”

“…Visceral obesity was defined as VFA > 160 cm 2 for male patients and >80 cm 2 for female patients. 25 26 Subcutaneous fat index was defined as ≥50.0 cm 2 /m 2 in men and ≥42.0 cm 2 /m 2 in women 27 (Table 1).…”