Ângulo de fase, domínio físico de qualidade de vida e funcionalidade em pacientes com câncer submetidos a quimioterapia.

Abstract

Introduction: Nutritional impairment, especially malnutrition, is frequent in cancer patients, which is associated with changes in body composition, such as reduced muscle mass and consequent reduction in functional capacity, lower quality of life, and shorter survival of these patients. Non-invasive methods such as bioelectrical impedance have been widely used in clinical practice for body assessment. Phase angle is obtained from the electrical bioimpedance, a measure that is related to cellular integrity and that is affected by the nutritional status of the patient in diseases such as cancer. The phase angle has been shown to be a prognostic indicator and may be related to the quality of life and functionality in these patients. Objective: to compare the variation of PA before and after chemotherapy treatment and to evaluate the correlation of PA, as an indicator of muscle mass, with the physical domain of quality of life and with functionality in a sample of patients with cancer. Methods: longitudinal study conducted with cancer patients undergoing chemotherapy for the first time. All patients aged 18 years or older, newly diagnosed and undergoing chemotherapy for the first time were included. To analyze the difference in the PA means according to the different classification variables, the t-test – or ANOVA – was used. The variation of the final and initial PA was evaluated through the linear regression test. The correlation between phase angle and physical domain and general health of the WHOQOL-bref, functionality and total score of the Patient-Generated Subjective Global Assessment (PG-SGA) were evaluated before the first cycle of chemotherapy and from the last assessment obtained from the patient through the Sperman correlation. Results: A total of 175 patients were analyzed, of which 66.3% were female. The mean PA of the initial assessment was significantly higher when compared to the final assessment of the patients’ PA (p=0.018). In both the initial and final assessments, the phase angle was correlated with the physical domain (r=0.29; p<0.001 and r=0.19; p=0.021) and with the functionality score (r=-0.32; p<0.001 and r=-0.30; p<0.001) and total PG-SGA (r=-0.31; p<0.001e r=-0.23; p=0.006). Conclusion: The phase angle can be considered a predictor of physical quality of life and functionality in cancer patients.