Predictors of quality of life in patients with breast cancer
Correspondence Address: Source of Support: None, Conflict of Interest: None DOI: 10.4103/IJPC.IJPC_119_18
Source of Support: None, Conflict of Interest: None
Introduction: Breast cancer is one of the most common cancers among women and is responsible for physical and sociomental problems. Evaluation of life quality is considered as an important issue in studying chronic diseases, especially cancer. Cancer affects the life quality of the patients in different degrees. Therefore, the effect of disease on life quality of these patients is an important consequence. Therefore, this study was conducted to determine the predictors of quality of life in patients with breasts cancer. Methods: This descriptive-analytical cross-sectional study was conducted in 2017 on 166 female under treatment for breast cancer who referred to Ghazi, Alzahra, Valiasr, and Shams hospitals in Tabriz city, Iran. Samples were selected through convenience method. Sociodemographic and quality of life questionnaires-Cancer 30 in breast cancer patients were completed through interview. Data analysis was performed using Pearson's correlation, independent t, analysis of variance, and linear multivariate regression tests. Results: The mean ± standard deviation of total quality of life score was 59.1 ± 17.4 from the achievable range of 0 to 100. The highest mean score was obtained for cognitive performance subscale (74.9 ± 23.8), and the lowest mean score was achieved for emotional performance subscale (51.4 ± 21.1). According to the results obtained from the linear multivariate regression, variables of time of disease diagnosis, lifestyle, caregiver person, caregiver health status, and matrimonial satisfaction were among the predictors of total quality of life score. Conclusion: The results showed that quality of life in patients under treatment for breast cancer was moderate; therefore, special attention must be paid by caregivers to improve the quality of life in these patients considering its sociodemographic predictors.
Keywords: Breast cancer, quality of life, Iran
By decreasing contagious diseases and increasing life expectancy globally, the problems of patients with cancer have increased in low-income countries and following heart diseases, the second reason for death all over the world is cancer whose global prevalence has been doubled in the past 30 years. Cancer is a serious problem in Iran and all over the world. Today, breast cancer is one of the most serious concerns in women's health and is the second reason for death due to cancer after lung cancer among women. Breast cancer is a major challenge in public health globally and is the most common cancer in women in Iran and the world.,, Afro-Americans suffer a disproportionate share of cancer and death. In the United States, the chance of breast cancer is about 1 out of every 37 women (2.7%). As a developing country, Iran is in a medical transition period from contagious to noncontagious diseases. According to the reports of the World Health Organization (WHO), the percentage of women with breast cancer in Iran is 27% which comprises the highest share compared to other cancers. Breast cancer is the fifth reason for death due to cancer in Iran. In our country, 1 out of every 10–15 women may get breast cancer; but the age of getting breast cancer in developing country including Iran is one decade earlier than developed countries.
Fortunately, factors such as early diagnosis, successful treatment, and correction of risk factors have increased the life expectancy of patients with breast cancer in recent years. On the other hand, treatment of breast cancer and its side effects after the first treatment may be followed by negative effects on quality of life in these patients. Side effects of treatment in women under treatment for breast cancer can directly affect the quality of life at home and workplace.
Quality of life is an important consequence in breast cancer since it is effective in the prognosis of the disease and it can be applied to control patients, medical decisions, symptoms, and signs as well as planning for supportive healthcare interventions. According to the definition of the WHO, quality of life is the perception of an individual of his position in a systematic framework of culture and values in which he\she lives and it is also associated with the hops, expectations, standards, and concerns of that individual. Today, quality of life is being considered as a consequence of treatment of diseases and is evaluated as a determining indicator. Quality of life is a multidimensional structure including different emotional, physical, sexual, and social performance matrices. Physical domain is related to the mental evaluation of health and body performance status (e.g., pain, fatigue, incontinency) and emotional domain includes mental performance including positive and negative indicators of moods (e.g., stress, depression symptoms). Furthermore, emotional problems in the life of the individual can restrict his\her perception of health and performance status of the body. Social domains generally include the effect of disease on sociopersonal role and perception of social support in the individual.
Patients with breast cancer need complete and comprehensive physical, mental, and social care so that they can enjoy life with proper quality. Taking proper measures for controlling the consequences and treatment of the disease as well as improving their quality of life seems to be essential such that improving and enhancing the quality of life should be one of the primary goals in cancer treatment. Variations in the quality of life have to be closely considered throughout the treatment period in breast cancer, and treatment consequences and mental concerns such as fear should be addressed. Predictors of quality of life can help clinical experts identify patients in the risk of low quality of life. When those properties or situations can be balanced, an intervention to change them can result in improvements in the quality of life in the patients.
Due to the prevalence of breast cancer and the importance of its effects on all dimensions of the patients' life and low attention of our society to the concept of quality of life and related factors, we decided to conduct research with the aim of determining predictors of quality of life in patients with breast cancer. Identification of these factors helps the health-care staff of the society to organize their activities to improve health level and quality of life in the patients.
Study design and participants
This was a descriptive-analytical cross-sectional study which was conducted on 166 women with breast cancer who referred to Ghazi, Alzahra, Valiasr and Shams hospitals in Tabriz city, Iran. Inclusion criteria for the study were as follows: having Stage I, II, III and in situ breast cancer and its registration in the medical file, willingness to participate in the study, and being literate to read and write. Exclusion criteria were as follows: taking of psychological drugs, having significant background diseases such as physical and mental diseases, other cancers, occurrence of stressful events in the last month, Stage IV and end stage.
According to Monfared et al. on quality of life, sample size was calculated based on the highest standard deviation (SD) in subdomains of quality of life (SD = 12.45), α = 0.05 with precision (d) = 0.05 around the mean value (M = 53.86) to be 166 people.
Samples were selected through convenience method. After the approving the research by the ethical committee of Tabriz University of Medical Science (Ethics code: IR.TBZMED.REC.1395.10), sampling was started. The researcher referred to the hospital and introduced herself, described her aims of the research, ensured the confidentiality of the obtained information, and evaluated the patients regarding eligibility criteria. When patients had eligibility criteria and had the willingness to participate in the study, their informed consent was obtained and sociodemographic, and quality of life questionnaires were completed through interviews with patients. Before the interview and filling out the questionnaires, all participants were informed that all their information would be confidential and they will be able to withdraw from the study when they wanted.
Data collection tools
Sociodemographic and quality of life questionnaires-Cancer 30 (QLQ-C30) questionnaires were used for data collection.
QLQ-C30 were consisted of 30 questions which were used for the evaluation of the quality of life. In this questionnaire, the quality of life was measured from 0 to 100 in five functional domains (physical, role play, emotional, cognitive, and social), nine symptom domains (fatigue, pain, nausea and vomiting, shortness of breath, diarrhea, constipation, insomnia, anorexia, and economic problems due to disease) and one overall domain. In functional domains, higher scores indicate a better status while in symptom domains, higher scores indicate more serious symptoms and problems. Validity and reliability of the questionnaire for evaluating the quality of life in patients with breast cancer in Iran was performed by Safaee et al. and all domains had good validity and reliability.
In this study, for determining the validity of the sociodemographic questionnaire, content and face validity was used. Furthermore, by conducting test and re-test on 30 people with a 2-week interval, the reliability of the quality of life questionnaire was investigated regarding Cronbach's alpha coefficient and Intra-class Correlation Coefficient (ICC). Cronbach's alpha coefficient for the quality of life, social functioning, physical functioning, financial problems, role play, all domains and symptoms of quality of life except vomiting, and vomiting were determined to be 0.98, 0.93, 0.98, 0.89, 0.99, 1, and 0.80, respectively. Furthermore, ICC for the quality of life, social functioning, physical functioning, financial problems, role play, all domains and symptoms of quality of life except vomiting, and vomiting were determined to be 0.98, 0.93, 0.98, 0.89, 0.99, 1, and 0.80, respectively.
Data were analyzed using SPSS 21 (IBM, Armonk, NY, United States of America). For describing sociodemographic characteristics and quality of life, descriptive statistics including frequency, percentage, mean, and SD were used. To determine the relationship between some sociodemographic characteristics and quality of life, first one-way analysis of variance and independent t-tests were performed. Then, for adjusting the confounding variables and determining variance coefficients, independent variables (socio-personal characteristics) which were related to the dependent variable (quality of life) with P < 0.2 were simultaneously entered into multivariate linear regression model with backward strategy.
About half of the women (41%) were in the age group of above 50 years. Mean (SD) of the age of women was 50.0 (11.4) years. About 41% of the women were under treatment. About one-fifth of women (21.1%) and men (22.9%) had university education. Most of the patients (80%) lived in the cities. More than half of the patients (60.8%) stated that their disease period was 1 year. About three-fourths of the patients (72.3%) were housewives. About half of the women (47.6%) had 1–2 children. More than half of the patients (54.2%) stated that their monthly income was not enough to afford their expenses. About half of the women (49.4%) were under treatment for Stage II disease. More than three-fourths of the patients (79.5%) were married. More than one-fourth (27.1%) of the spouses of the patients were self-employed. More than three-fourths (86.7%) of the patients lived with their family. About half of the patients (47.6%) had average marital satisfaction. The majority of the patients (89.2%) did not express cancer history in their first-degree family members. Among 18 patients who had expressed disease history in their family, 9 expressed disease history in their mothers and 9 in their sisters. The majority of the patients (92.2%) were under combinational treatment. In about one-third of the patients (34.9%), spouses were the caregivers. The majority of the caregivers (94.6%) had good general health status [Table 1].
The mean (SD) of an overall score of quality of life was 59.1 (17.4) from the achievable range of 0 to 100. The highest and lowest mean (SD) scores were obtained for cognitive functioning (74.9 [23.8]) and emotional functioning (51.4 [21.1]), respectively. In the domains of symptoms and signs, the highest and lowest mean scores were obtained for diarrhea (92.4 [19.3]) and pain (22.9 [4.6]), respectively [Table 2].
Variables of time of disease diagnosis, children number, disease stage, lifestyle, marital satisfaction, treatment type, caregiver, and general health status of caregiver had a relationship with quality of life with P < 0.2 and were entered into multivariate regression model with backward strategy. Finally, variables of time of disease diagnosis, lifestyle, caregiver person, health of caregiver, and marital satisfaction were remained in the model and were assumed as the predictors of an overall score of quality of life [Table 3].
The mean total score of quality of life in patients under treatment for breast cancer was at a moderate level. Patients with breast cancer obtained the highest score in cognitive functioning and lowest score in emotional functioning. Regarding symptom domains, diarrhea was the most commonly observed symptom in the patients and pain was the least common in patients under treatment for breast cancer. Prospective and comparative study of Rohani et al. with the aim of determining changes in quality of life and the feeling of dependence in women with breast cancer was conducted in Tehran-Iran using QLQ-C30 Version 3 questionnaires before and 6 months after breast cancer diagnosis. Compared to control group, women with breast cancer did not have good status in physical functioning, role play and financial problems domains during 6 months follow-up. The difference between our results and those obtained by Rohani et al. may be because the stage of the disease in the patients studied by Rohani et al. were higher and high costs had been imposed to patients during 6 months follow-up for surgery and treatment and they did not have much time to take care of themselves and fulfill their responsibilities in their families. The descriptive-analytical study of Monfared et al. (2013) was also conducted with the aim of investigating quality of life and related factors on 170 women with breast cancer who had undergone surgery and finished chemotherapy and radiotherapy treatments and at least 2 years had passed the end of their treatment period and had referred to the clinic of Razi educational center and oncological center of Gilan-Iran for follow-up. The findings showed that the emotional functioning domain had the lowest mean score and time of disease diagnosis for the majority of patients were in the 1st year. The findings of the mentioned study are consistent with the present study. This showed that in both studies not much time had passed the diagnosis of the disease and chemotherapy, surgery, and combinations treatments in these patients and still some patients suffer from destructive mental and emotional effects due to the diagnosis and treatment of their disease. Quality of life is considered as an effective structure in the lives of patients with breast cancer, and early diagnosis of breast cancer have significant positive effects on the quality of life and may increase the survival rate of these patients.
The obtained results showed that the variables of time of disease diagnosis, lifestyle, caregiver, the health status of caregiver, and matrimonial satisfaction were identified as the predictors of quality of life in these patients.
In this research, women whose disease had been diagnosed 2 or more years before, had lower quality of life compared to those with 1 year of disease diagnosis. The results obtained by Holzner et al. in Australia regarding the relationship between time of disease diagnosis and quality of life showed that the duration of disease decreased the quality of life in patients with cancer which is consistent with our findings. This can be due to mental and psychological problems during disease diagnosis period and the shock induced by being informed of the disease.
In this study, patients who lived apart from their families had a lower quality of life compared to those living with their families. In the study of Monfared et al. also a statistically significant relationship was found between living conditions in the family of the patient and the quality of life such that patients living with their families enjoyed a higher quality of life which is in line with our findings.
According to our findings, patients whose caregivers were their mother, sister, or others had a lower quality of life compared to those whose caregivers were their spouses. The results obtained by Parker et al. showed that the presence of family and their support, especially their spouses, were among the predictors of quality of life in the cancer patients such that increasing the support of spouses increased the quality of life in patients which are in line with our findings. Furthermore, in line with our findings, the results obtained by Julkunen et al., in Finland was performed with the aim of determining the association between quality of life and support of spouse in cancer patients showed that spouse as caregiver played an important role in the quality of life in patients with cancer and the support of spouse as caregiver was related to the quality of life in patients.
In this research, women whose caregivers were not in good health status had a lower quality of life compared to those whose caregivers were in better health status. It seemed that the health of the caregiver could affect the procedure of patient support during caregiving and with different supportive approaches they can increase their quality of life.
According to our results, women with moderate matrimonial satisfaction had a higher quality of life compared those with lower matrimonial satisfaction. The results obtained from Zeygami and Gaffari study showed a significant association between matrimonial satisfaction and quality of life in the patients such that in better sexual function and higher matrimonial satisfaction of the patients, their quality of life was also higher and this was in line with our findings.
Among the limits of this research was that, due to the cross-sectional nature of this research, the observed relationships were not necessarily indicative of a causative relation. It is suggested that more qualitative and quantitative research be conducted on the effective factors on the quality of life in patients with breast cancer whose results can help provide effective strategies in this regard.
Our results showed that the quality of life in patients with breast cancer was moderate; therefore, special attention has to be paid by caregivers to improve quality of life in patients with breast cancer considering their sociodemographic determinants. Today, survival alone is not considered, and patients demand a higher quality of life. By having positive relations and using psychological techniques and sociopersonal support (personal consulting, supportive groups, calming, adaptive skills, etc.), and most importantly creating relations with mutual understanding and respecting the patient, caregivers can play critical roles in controlling and treating the disease and therefore improving quality of life in clinical situations.
This research was a part of a Master degree dissertation in Tabriz Medical Sciences University (moral code number: IR.TBZMED.REC.1395.10). Herein, we want to acknowledge the research deputy of Tabriz Medical Sciences University, Alzahra, Ghazi, Shams, and Valiasr Hospitals in Tabriz city, and all participants in this research.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
[Table 1], [Table 2], [Table 3]