High Charlson comorbidity index value is not associated with muscle strength in unselected cancer patients

Cancer patients usually lose muscle mass and strength during progression of tumor or treatment. One of the simplest, easiest, and cheapest methods to assess muscle strength is by handgrip strength (HGS), which has been widely used during clinical practice. However, it is not established whether the presence of comorbidities, when assessed by the Charlson Comorbidities Index (CCI), is associated with lower HGS in cancer patients. Thus, this study sought to verify if low HGS is associated with highest CCI in cancer patients.

Cross-sectional study enrolled 167 cancer patients of both sexes diagnosed with cancer. The sample was divided into two groups, CCI <5: low comorbidity or CCI ≥5: high comorbidity number. Muscle strength was assessed by digital dynamometer. Student t and Chi-square tests were performed to analyze the differences between groups and logistic regression was used to verify the association between CCI and HGS, in the crude (model 1) and adjusted for confounding variables (model 2).

Patients from the CCI ≥5 group were older (65.0 ± 11.3 vs. 55.3 ± 13.1; p < 0.05), hospitalized (p < 0.05), and the gastrointestinal and accessory organs of digestion tumors were more prevalent when compared to the CCI <5 group. The logistic regression in the crude model showed a negative association between CCI and HGS (OR: 0.94 [95%CI: 0.90-0.98], p = 0.006), however, after adjusting for confounders variables this association was lost (OR: 0.98 [95%CI: 0.94-1.03], p = 0.58).

In patients with cancer, there is no independent association between HGS and CCI.