3.1 Characteristics of the Study Sample
The mean age of the 250 Emirati women was 53.4 (SD ±11.3), and the median age was 52 years; the range was 59 (27 was the minimum and 86 the maximum). The mean time elapsed since diagnosis was 4.44 (SD ±4.3), with a minimum of 0 (year 2021) and a maximum of 25 years (year 1996) (Table 1).
Out of the 250 participants, 99 (39.6%) were diagnosed in 2020, while 45 (18%) were diagnosed more than 5 years ago.
The majority of women (70%) were from Dubai Hospital, while 30% were from Tawam Hospital. More than half of the participants (56.8%) were from Dubai, 19.6% were from Abu-Dhabi, 12% were from Sharjah, and 11.6% were from the other emirates (Ajman, Rass al Khaimah, Um Al Quwain, and Fujairah).
The majority of women (95.2%) never smoked, and 87.6% of them had children, with a mean number of 4 (SD ±3) children (a maximum number of 10 children). Approximately 39% of the participants exercised on a daily basis, and approximately 4% lived alone. In total, 44% of them had had a miscarriage, with a mean number of 1 (SD ±1.3) miscarriages (a maximum number of 6 miscarriages). More than a quarter (25.6%) of the participants had a family history of BC, and 11.6% had the cancer spread to other parts of their body.
3.2 Quality-of-life scale scores
The global health/QoL mean score of the 250 participants was 74.73 (SD ±18.25), with a minimum of 16.67%, indicating a good level of wellbeing (Table 2).
On the QLQ-C30 scales, the mean scores for the five functional scales ranged from 68.43 to 82.33, showing mostly a good level of functional health status. While social functioning scored the highest (82.33 ±28.38) among the functional scales, emotional functioning scored the lowest (68.43 ±30.02).
On the symptom scales, the most worrying symptom was sleep disturbance (47.87±38.46), followed by fatigue (38.18±30.31) and pain (29.13±28.01). Financial impact scored the lowest, indicating that most women did not have financial issues related to their cancer. Out of the 250 participants, 5.6% to 12.4% had problematic functioning on the functional scales but worse functioning on the symptom scales, as 6.8% to 45.6% had problems with symptoms.
On the QLQ-BR23 scales, the range of the mean scores for the functional scales was 50.80 to 80.30, showing mostly above average to good levels of functional health status. While sexual functioning scored the highest (86.07±22.61) among the functional scales, future perspective scored the lowest (50.80±37.92).
On the symptom scales, the most worrying symptom was upset by hair loss (61.01±37.35), followed by arm symptoms (33.73±28.08). Notably, all symptom scales means had 0 as the minimum score and 100 as the maximum score, with the exception of systemic side effects, for which the maximum was 95.42. Out of the 250 participants, 2% to 24% had problematic functioning on the functional scales but worse functioning on the symptom scales, as 12% to 40% had problems.
3.3 Factors Associated with Quality-of-life Scale Scores
3.3.1 Global Health, Functional, and Emotional Scales on the QLQ-C30
Table 3 shows that there were significant differences in the global health/QoL means across categories of monthly income (P =0.018), physical activity (P =0.0004), history of metastases (P=0.001), and type of treatment (P= 0.045 for chemotherapy). Post hoc analysis showed that participants who had regular physical activity, had high income, had no history of metastases, and were not treated with chemotherapy seemed to have better global health-related QoL.
Furthermore, significant differences in the physical functioning means were observed across categories of monthly income (P =0.007), physical activity (P <0.0001), history of metastases (P=0.027), and disease stage (P =0.025). Post hoc analysis showed that participants who had regular physical activity, had high income, had no history of metastases, and were in early pathological staging had better functioning on the physical functioning scale
Differences in the emotional functioning means were observed across categories of age, educational level, menopausal status, lymph node dissection (P <0.0001 each), time since diagnosis (P =0.002), history of metastases (P =0.001), employment status (P=0.014), and monthly income (P=0.018. Post hoc analysis showed that participants who were aged above 50, were long-term survivors, were not employed, went through normal menopause, and had no history of lymph node dissection had better emotional functioning (Table 3).
3.3.2 Symptom Scales on the QLQ-C30
With the exception of appetite loss and constipation, there were significant differences in all symptom scales across age categories. Women aged below 50 had worse symptoms on the symptom scales than those aged above 50. Moreover, there were significant differences in the mean pain scores by time since diagnosis (P=0.026), pathological staging (P=0.007), menopausal status (P = 0.010), education level (P=0.012), monthly income (P=0.005) and metastasis categories (P = 0.035). Post hoc analysis revealed that those who were older, were long-term survivors, were postmenopausal, and had a minimum education level (primary) experienced more pain.
Furthermore, there were significant differences in financial impact across age, menopausal status, monthly income, lymph node dissection, and chemotherapy. Post hoc analysis revealed that those who were older, postmenopausal, had an average salary, and had undergone lymph node dissection or chemotherapy experienced more financial impact.
3.3.3 Functional and Symptom Scales on the QLQ-BR 23
As shown in Table 4, differences in the means of body images were significant among the categories of all independent variables with the exception of a history of metastases, radiology, and lumpectomy. Post hoc analysis showed that those who were younger, were employed, were premenopausal, were single, had low income, had undergone chemotherapy or dissection and were highly educated seemed to have poorer body image.
Better sexual functioning was observed for women who were aged above 50 (P<0.0001), were long-term survivors (P = 0.001), were not working (P<0.0001) and had gone through natural menopause (P<0.0001). Furthermore, post hoc analysis showed that women aged above 50 and those who had radiology as treatment tend to have better sexual enjoyment functioning.
More intense upset by hair loss was noted among women who were aged above 50 (P = 0.047).
Additionally, women aged above 50 had worse systemic side effects (P <0.0001) and breast (P <0.001) and arm (P = 0.001) symptoms.
Women who had surgical menopause complained of more severe systemic side effects (P = 0.017) and breast (P = 0.006) and arm (P = 0.019) symptoms than women who had menopause naturally.
Women who were recently diagnosed complained of more severe arm symptoms (P = 0.001), and women in advanced pathological staging complained of more severe systemic side effects.
3.3.4 Predictors of Quality of Life
Table 5 below summarizes the adjusted regression models for the QLQ-C30.
As shown in Table 5, the predictors explained 14% of the variation in global health, 23.8% of the variation in emotional functioning, 19.2% of the variation in cognitive functioning, and 21.7% of the variation in social functioning. Monthly income was the only predictor that had a significant effect on global health/QoL given the other predictors in the model (P = 0.002). While age was significant only in emotional functioning (P= 0.004), education was a significant predictor in the emotional and social functioning models (P = 0.008 and 0.019, respectively). Metastases and mastectomy were significant only in the cognitive functioning model (P = 0.008 and 0.019, respectively). Lymph node dissection was significant in the emotional, cognitive, and social functioning models (P = 0.029, 0.017, and 0.027, respectively).
The important results of the regression analysis of the QLQ-C30 symptoms scales are that predictors explained 17.5% of fatigue, 16.3% of pain, and 23.4% of insomnia. Additionally, radiology was the only significant predictor in explaining fatigue, education was more important in explaining pain (P=0.035), and advanced staging was important in explaining insomnia (Table of all results can be found in the Appendix).
From the linear regression model with parameter estimates for the QLQ-BR23 functional and symptom scales (Appendix), the predictors explained between 16.2% and 46.5% of variation in all scales of the QLQ-BR23 with the exception of the upset by hair loss symptom. Late survivor was the only predictor that had a significant effect on breast symptoms given the other predictors in the model (P = 0.009), while radiology was the only predictor that had a significant effect on arm symptoms (P= 0.006).
Age and employment were significant predictors of sexual functioning (P= <0.0001 and 0.018, respectively). High income and mastectomy were significant predictors in the sexual enjoyment model (P = 0.020 and 0.044, respectively).