Assessment of the impact of comorbidity on the survival of cancer patients treated by palliative care teams.

Abstract

The usefulness of the age-adjusted Charlson Comorbidity Index (ACCI) as a gauge of the impact of comorbidity on survival is known in the geriatric population. In palliative care, there is little research studying the correlation between comorbidity and survival in the advanced stages of oncological disease. The aim of our study was to explore the impact of comorbidity, measured with the ACCI, on survival in our patients. Our hypothesis was that higher ACCI scores would be associated with lower survival rates after the first visit. We conducted a prospective observational study over one year. Patients were attended by palliative home care teams. The main variables were: survival from metastatic disease after the first visit and ACCI score on the first visit. We also employed a descriptive analysis and a Kaplan-Meier survival analysis, including different ranges of ACCI scores. The final sample included 66 subjects. The standard patient was a 76-year-old man with lung cancer who had received chemotherapy. The overall average ACCI score was 10.45. Significant differences were found between the different locations of metastatic disease (greater survivals in breast, ovary, and prostate; p = 0.005) and some treatments (hormone and radiotherapy; p = 0.001 for each), but not from the first visit. We found lower survival rates among lung cancer patients with higher comorbidity (ACCI ≥ 11, p = 0.047), with no differences on other primary locations or overall values. The data show that comorbidity measured by the ACCI may be an interesting prognostic factor during the late stages of disease, as we have found in lung cancer. More research is certainly needed.