Measuring quality of life (QoL) is critical in oncology, as both cancer and its treatment can exert a negative impact of the perception of this construct. A diagnosis of cancer is accompanied by substantial changes in one’s way of living as well as physical and emotional changes. Cancer is also accompanied by stigmas and a feeling of finitude in the face of a disease that many still consider to be uncurable (20).
In the present investigation, overall QoL was considered relatively good among the participants, but those under palliative care had a poorer perception of the construct. In this group, substantial impacts were found on the physical wellbeing, psychological wellbeing and symptoms domains compared to the other groups.
The progression of the disease and symptoms contribute to a poorer QoL, as described in a randomized study involving 733 patients with advanced or metastatic lung cancer submitted to different medicinal treatments (21). More than half of all oncology patients have five common symptoms that can affect one’s perception of QoL, namely, fatigue, weakness, pain, weight loss and anorexia, demonstrating the close relationship between health and quality of life (12). Indeed, a study found that QoL was lower among patients with lung cancer compared to that of the general population, as this construct is affected by disease severity and the number of symptoms; moreover, fatigue and respiratory problems exerted a negative impact on the psychological dimension of QoL (22). Another study involving 158 patients with advanced cancer found that high levels of hopelessness, a compromised body image and emotional suffering were the main factors associated with psychological stress (23).
Total functioning scores were good in the present study, but the median was significantly lower in the group of patients under palliative care, demonstrating that this group had worse functioning and a poorer prognosis. This group also had a lower proportion of patients in the stable stage.
A study conducted in the northeast of Brazil with 100 patients under palliative care found that 62% of the patients had PPS scores between 80 and 90 (24), differing from the findings of the present investigation. A study conducted in Canada with 7882 oncology patients found that PPS scores dropped in the last six months of life, with an initial mean score of 68.4 diminishing to 54.7 and 41.3 in the month and week prior to death, respectively, indicating compromised functioning, autonomy and performance on activities of daily living in the final weeks of life (24). A multicentric study involving 1739 patients with advanced cancer undergoing palliative care at 30 healthcare centers in 12 countries found a significant reduction in quality of life and functioning prior to death in comparison to the preceding three to five months (25).
In the present study, multiple linear regression analysis of the QoL scores, PPS scores and explanatory variables revealed statistically significant positive associations between QoL and age, being under palliative care, male sex, income and pain control. These results are in agreement with data reported in a previous study conducted in Brazil involving 96 patients under palliative care, in which male participants had a better perception of QoL. In a study developed in Sweden based on the analysis of records from the last week of life of 26,976 adults who died of cancer in 2011–2012, an advanced age was a risk indicator for poor end-of-life care quality (26).
Another finding of the present investigation was the fact that patients without pain control had a better quality of life. This finding is likely due to the fact that these participants did not have the symptom.
In the present study, income was associated with QoL. A previous study conducted with 327 survivors of cervical and breast cancer also found that income was a determinant factor of QoL.
Diminished functioning was associated with age, the palliative care group, income and pain control. These factors also exerted an influence on QoL, demonstrating that the degree of functioning alters one’s perception of quality of life.
However, this investigation also showed that QoL is unique to each individual, as it is linked to personal values and often changes with the progression of the disease. Moreover, the perceptions of individuals regarding their QoL can evolve and change over time (27).
The present study has limitations that should be considered. The interviews were held at a single moment in time, which may not be sufficient to detect the magnitude of changes experienced by the individuals in the different groups. Moreover, the study was conducted at a single center with local particularities and a heterogeneous group of participants in terms of the type of cancer and clinical condition.