|Year : 2014 | Volume
| Issue : 4 | Page : 550-556
Predictors of quality of life in patients with colorectal cancer in Iran
Maryam Momeni1, Atefeh Ghanbari2, Farahnaz Jokar3, Abbas Rahimi4, Ehsan Kazemnezhad Leyli5
1 MSc, Nursing Education, Qazvin University of Medical Sciences, Qazvin Nursing and Midwifery College, Rasht, Iran
2 PhD, Nursing Education, Social Determinants of Health Research Center, Guilan University of Medical Sciences, Rasht, Iran
3 MSc, Nursing Education, Gastrointestinal and Liver Diseases Research Center, Rasht, Iran
4 MD, Department of Radiation Oncology, Razi Hospital, Guilan University of Medical Sciences, Rasht, Iran
5 PhD in Biostatistics, Guilan Road Trauma Research Center, Guilan University of Medical Sciences, Rasht, Iran
|Date of Web Publication||1-Feb-2016|
PhD, Nursing Education, Social Determinants of Health Research Center, Guilan University of Medical Sciences, Rasht
Source of Support: None, Conflict of Interest: None
Background: Colorectal cancer (CRC) is one of the most common invasive cancers and is responsible for physical and psychosocial morbidity. Quality of life (QOL) is an important outcome for these patients. The aim of this study was to determine the predictive factors of QOL in patients with CRC. Materials And Methods: A cross-sectional design was used to assess 110 patients with CRC who referred to Oncology Department of Razi Hospital, Guilan. Data were collected by structured interview with patients and review of medical records. Generic and specific QOL were evaluated by short form-36 and functional assessment of cancer therapy-colorectal, respectively. Generalized linear models identified variables significantly associated with QOL. Results: Out of 110 patients with CRC, 58.2% were men. Mean age of patients was 58.33 ± 12.39 years. Mean of Generic and specific QOL were 70.92 ± 15.56 and 95.72 ± 19.18, respectively. In regression analysis, age, sex, living condition, health insurance, hospitalization frequency, Karnofsky performance status, and co-morbidity were predictors of generic QOL and age, sex, living condition, health insurance, monthly income, family history of CRC, Karnofsky performance status, and co-morbidity were predictors of specific QOL in patients. Conclusion: There are nine socio-demographic and clinical factors that are significant predictors of QOL in patients with CRC which should be considered in treatment and care of patients. The findings of this study should be the target of future research, emphasizing the need for interventional studies that minimize the adverse impact of the disease symptoms on the QOL in patients with CRC.
Keywords: Colorectal, neoplasm, quality of life
|How to cite this article:|
Momeni M, Ghanbari A, Jokar F, Rahimi A, Leyli EK. Predictors of quality of life in patients with colorectal cancer in Iran. Indian J Cancer 2014;51:550-6
| » Introduction|| |
Colorectal cancer (CRC) is one of the most common cancers worldwide with over one million new cases annually. Some evidence show a growing rate of CRC particularly in youth (<40 years) in Iran. CRC is known as an almost common (5000 new cases per year in Iran) and fatal condition, which is responsible for a remarkable rate of physical and psychosocial morbidity. About 5000 Iranian people (7 per 100,000 populations) deal with CRC annually. Yet, mortality result from CRC has been declined due to early diagnosis and advances in treatment resulting in survival of 60% over 5 years , and quality of life (QOL) is a main consequence in these patients within past two decades.,,
The magnitude of evaluating the outcomes of cancer in terms of patient's survival and QOL during and following the treatment phase has been confirmed.,, QOL assessment in oncology indicates the unmet emotional, social, and spiritual concerns in patients beside being beneficial in evaluation of the impacts of disease on survivors. Patients with stoma and without stoma have frequent or irregular bowel movements, diarrhea, flatulence, and fatigue and often have to observe dietary limitations. Determining the QOL of patients with CRC seems necessary to evaluate the manner that this disease affects individuals, their families, and environment. In spite of the burden and prevalence of CRC, there is not much information related to QOL of survivors after the first year post-treatment.
The findings demonstrate several factors influencing an individual's evaluation of their QOL and the fact that they must be considered in management and treatment of cancerous patients. Comprehending the characteristics or conditions which predict further QOL can aid the clinicians to recognition those who are at risk of poorer QOL. Moreover, if a characteristic or condition needs to be altered, an intervention should be implemented to create improved QOL. The information may be as a way to identify the complications of these patients and could be considered to support them so that they could be a useful person for their family and society despite of disease burden and its complications. Variety in ethnicity, culture, and socio-economic status can make the different factors related to QOL among CRC survivors. Many of aforementioned studies consider western populations.,,,,, Also, little is known about the QOL in CRC survivors in Iran where prevalence of CRC is increasing. In our country, in spite of the importance of QOL concept in patients with CRC, no organized study is published in this area. Regarding limited information on QOL in CRC survivors in our country (Iran), we conducted a cross-sectional study to determine the QOL predictors in these survivors; regarding this issue and that the Oncology Department is the only referral center of these patients in Guilan province, North of Iran, the researchers decided to evaluate the generic and specific QOL in CRC survivors and predictive factors which may enhance their QOL.
| » Materials and Methods|| |
A convenient sample (N = 110) of patients with CRC between 20 and 80 years at the time of diagnosis was enrolled in this cross-sectional Study. Patients referred to Oncology Department of Razi Hospital in Guilan (North of Iran) from April 2010 to March 2011. They were eligible if they had survived at least 1 year from diagnosis; they provided written informed consent form prior to inclusion, show no overt psychotic illness, and talk or write Persian language easily and correctly. Only patients were operated with a curative aim and who were free of recurrence throughout the surgery period were included. Patients suffered from another cancer were excluded.
Participants answered a three-part questionnaire including socio-demographic and clinical characteristics; generic QOL instrument based on short form (SF)-36 questionnaire; and disease-specific instrument for CRC patients. Socio-demographic characteristics included age, sex, marital status, employment, education, living condition, place of residence, monthly income and health insurance and clinical characteristics were time since diagnosis, Karnofsky performance status, hospitalization frequency, chemotherapy and radiotherapy frequency, site of cancer, stage of cancer, colostomy, family history of CRC, and co-morbidity.
The SF-36 evaluates generic QOL which includes eight multi-item scales. The subscales have a possible range of 0-100, with higher scores indicating better functioning and/or well-being. The acceptable internal consistency and test–retest reliability have also been confirmed in general Iranian population.,
The functional assessment of cancer therapy-colorectal (FACT-C; Version 4) is a 36-item specific QOL questionnaire with five subscales. Patients were asked to rate how they have felt over the past 7 days, on a scale of 0 (not at all) to 4 (very much). The overall QOL score can range from 0 to 144, with higher scores indicating better QOL. Each subscale has a maximum score of 28, except for the emotional well-being subscale, which has a maximum score of 24. The questionnaire has confirmed reliability and validity. The FACT-C version 4 was translated into the Persian language. Forward translations were performed by one oncologist and an Iranian professor of English literature performed the reconciliation of two forward translations. Then, a native bilingual English speaker translated it back into English. To examine the validity of FACT-C questionnaire, we used content validity. Pilot study was performed on 20 patients with CRC. Cronbach's α coefficient was 0.89 for all dimensions of FACT-C indicated acceptable internal consistency.
The Charlson–Deyo co-morbidity index is a weighted 19-item index, and the overall score is the sum of the weights of each co-morbid condition reported by the patient. In this study, a single researcher carefully assessed every co-morbid condition requiring medical care by reviewing charts and other medical records and by interviewing patients. Co-morbidities which were existence before hospital admission were considered. The Karnofsky performance status scale (KPSS) is the most widely used method of quantifying the functional status of cancerous patients. KPSS ranges from 0 to 100, in 10-point increments, to define 11 various performance status levels from dead (0) to quite normal functioning (100).
We called patients with inclusion criteria who had referred to Oncology Department of Razi Hospital, Guilan. Data were collected by one researcher through structured interview. Each interview took almost an average of 25-30 min. The stage of cancer was indexed using the tumor node metastasis (TNM) classification system with data taken from medical records and pathology reports. Written informed consent was obtained from all patients prior to their participation in the study. The Ethical Committee of Oncology Department of Razi Hospital, Guilan approved this study.
Categorical and continuous variables were presented as mean (standard deviation) and frequency (percentages), respectively. Univariate comparisons (one-way analysis of variance, two-tailed t-tests, and Pearson's correlations) were first conducted in order to assess relationships between all independent variables and all dimensions of generic and specific QOL. Factors significant at P < 0.1 on univariate analysis were analyzed using multiple regression analysis to determine independent predictors of QOL. We used hierarchical generalized linear models to identify variables significantly associated with generic and specific QOL. This multiple relationships evaluated as stepwise; that is, in each phase of analysis, non-significant variables (P > 0.05) with highest P value excluded from model. In multiple regression analysis, for categorical variables, category with higher mean of QOL scores in univariate analysis considered reference group. All the statistical analyses were performed using SPSS 16. P <0.05 was considered statistically significant.
| » Results|| |
The socio-demographic characteristics of the participants are summarized in [Table 1]. Their mean age was 58.33 ± 12.39 years. Majority of patients (58.2%) were men.
|Table 1: Socio-demographic characteristics of patients with colorectal cancer (N=110)|
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The clinical characteristics of the study population are shown in [Table 2]. The mean time after the first diagnosis was 38.23 ± 21.02 months. Co-morbidity mean scores and Karnofsky performance status were 1.89 ± 1.31, 87.64 ± 9.27, respectively.
|Table 2: clinical characteristics of patients with colorectal cancer (N=110)|
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The scores of generic QOL in terms of SF-36 are summarized in [Table 3]. In all, mean scores of SF-36 were 70.92 ± 15.56. Mean scores of vitality dimension were lower than other dimensions of SF-36 (62.8 ± 23.32).
|Table 3: Mean and standard deviation of short-form-36 domains scores for colorectal cancer patients|
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Mean (SD) of the scores of FACT-C dimensions are presented in [Table 4]. The mean of overall scores of FACT-C was 95.72 ± 19.18. Mean score of emotional well-being dimension was lower than other dimensions of FACT-C (16.26 ± 5.05).
|Table 4: Mean and standard deviation of functional assessment of cancer therapy-colorectal domains scores for colorectal cancer patients|
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[Table 5] and [Table 6] show the regression coefficients of predictive factors for generic and specific QOL. Results suggested that age, sex, living condition, health insurance, co-morbidity, and Karnofsky performance status were predictors of generic and specific QOL, whereas hospitalization frequency was predictor of generic QOL and monthly income. Moreover, family history of CRC was predictor of specific QOL.
|Table 5: Hierarchical generalized linear model for generic quality of life (short form-36)|
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|Table 6: Hierarchical generalized linear model for specific quality of life (functional assessment of cancer therapy-colorectal)|
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Older patients had higher generic and specific QOL scores than those who were younger (P < 0.04, P < 0.033, respectively). Women had lower generic and specific QOL scores than men (P < 0.001, P < 0.023, respectively). Patients who lived with parents reported higher generic and specific QOL scores than those living with spouse and children (P < 0.024, P < 0.001, respectively). Patients without health insurance had lower generic and specific QOL scores compared to those with health insurance (P < 0.023, P < 0.039, respectively).
Low monthly income status was significantly correlated with decreased specific QOL, as patients with income < 2,500,000 Rial (250.00$) reported lower specific QOL scores compared with those with income between 2,500,000 and 5,000,000 Rial (250.00-500.00$). Individuals with family history of CRC reported lower specific QOL scores than those without such history (P < 0.013).
Those with higher Karnofsky performance status were reported with higher generic and specific QOL scores (P < 0.001, P < 0.033, respectively). Furthermore, patient with co-morbidity had lower scores of generic and specific QOL than those without co-morbidity (P < 0.026, P < 0.003, respectively). Patients with higher number of hospitalization had lower generic QOL scores (P < 0.021).
| » Discussion|| |
A better understanding of the issues related to QOL in patients with CRC improves the current ability to understand the burden of disease on survivors and society and to design suitable interventions. Little is found about changes in QOL of these survivors overtime as studies evaluating QOL in CRC patients after 1 year post-surgery are scarce. The impact of socio-demographic and clinical variables on the reporting of generic and specific QOL in CRC survivors was discovered in this study.
In general, the survey population reported a relatively high level of generic and specific QOL. It has also been reported that QOL improves for survivors of CRC as they lived for longer periods. This has been explained by a reduction in illness-related demands and by patient's compatibility to the disease. Also, technical innovations such as staplers have declined the rate of definitive colostomies and a greater number of patients may undergo sphincter-saving procedure.
Lowest generic QOL scores were reported in the vitality dimension. This finding was also consistent with the study that Krouse et al. performed in America on 491 patients with rectal cancer. The findings, however, do not support the work of Anthony et al. in which 158 patients with CRC reported the lowest scores in the physical role. In this study, patients with disease recurrence were not excluded. Physical and functional status of patients with recurrence may be poorer compared with those without recurrence. This issue results in role performance disorder.
Lowest specific QOL scores were reported in the emotional well-being dimension. This result is also consistent with the study that Peddle et al. conducted on 413 patients with CRC. Whereas, Yoo et al. showed that mean score of CRC-specific concerns dimension was at lowest level. This finding was related to pre-operative period. Improvement sign and symptoms of disease after surgery increased mean scores of this dimension.
The related factors to QOL of western CRC survivors are summarized in [Table 7]. In our study, the women had higher scores of generic and specific QOL compared to men. This finding was in line with the previous study., Whereas, Schultz et al. reported in a study on 344 rural cancer patients by functional assessment of cancer therapies-General scale that mean of QOL in females compared with males was significantly higher. In this study, all patients were rural, whereas most of participants in our study were urban. We believe that female patients are playing principle role in family. Cancer and its treatments may reduce their ability for role performance and implementation of their responsibilities. In this study, the gender differences in disease symptoms were not considered. Future research should focus on the gender-associated differences of specific signs and symptoms in patients suffering from CRC and the various reasons for such differences.
|Table 7: Summary of studies describing related factors with generic and specific quality of life in patients with colorectal cancer|
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Patients who were single had the lowest scores of generic and specific QOL. A previous study has showed that unmarried patients showed significantly higher levels of distress than married patients. Marriage is probably considered the most important type of "social support" associated with a variety of physiological mechanisms affecting health. In addition to emotional support and access to social networks, the spouse can also play a major role in forming the health-related behaviors. CRC and its treatment can have an detrimental effect on social functioning including work and productive life, relationships with friends, relatives, and partners, and other social activities and interests. Culture is found to be a main element when comparing the results of this study with Western studies. In this study, family appeared as the most important support system. Also, living with parents has made higher scores of generic and specific QOL. Those who are living with parents compared with those living with spouse and children have fewer responsibilities for family; thereby, they may have lower economic problems. These results are in consistent with Iranian culture on satisfaction, social standing, self-suppression, and bonds of relationship.
Patients without health insurance had lower mean scores of generic and specific QOL compared with patients with health insurance. This finding is generally consistent with previous investigations.,, Insurance status is not a one-dimensional nature and mainly depends on personal and system attributes. Based on governmental data, more than 90% of Iranians are under the coverage of at least one type of health insurance. Health system network in Iran includes a referral system, starting at primary care centers in the periphery going through secondary-level hospitals in the provincial capital and tertiary hospitals in major cities. It consists of public and private parts. The public part provides primary, secondary, and tertiary health services. In this part, medical services such as prenatal care and vaccination are offered either free of charge or at very low cost. The private part has an important role in health care preparation in Iran. The private part commonly focuses on secondary and tertiary health care in urban regions. There are many non-governmental organizations (NGOs) active in health issues in Iran. NGOs are mainly active in special fields such as cancer and its treatment. Medical services in this part are not offered free of charge. Therefore, patients need health insurance to receive such services. Prior studies have also highlighted health-insurance status as a crucial factor in cancer prevention and screening services, as well as access to timely diagnostic care and required treatments. Patients without insurance or with Medicaid insurance (a US government program for low-income or medically needy individuals) usually use screening less frequently ,, and have more advanced cancer compared with patients who are privately insured., Even in individuals with higher income, lack of health insurance is related to a lower use of cancer screening tests. We claim that patients with cancer suffered many financial and economic problems. Health insurance, as a support system can be helpful in decreasing the therapeutic costs and financial concerns of patients.
Low monthly income status was significantly correlated with worse specific QOL. In a study on QOL, similar to ours, Ramsy et al. reported only low-income status associated with worse outcomes for various dimensions of QOL based on the FACT-C and Health Utilities Index. Patients with lower income have inadequate and poorer access to health care services.
There were several limitations in this study. First, there was a sampling bias because the results were obtained from only one institution, which was a university hospital. Other limitations include small sample size and convenience sampling method. Therefore, our results cannot be generalized to the general population with CRC. The strength of our study is the application of a well-established instrument to assess QOL. Also, we used a questionnaire specific to CRC.
The findings of this study should be noted in future research focusing on the need for interventional studies which decreases the adverse impact of the disease symptoms on the QOL in patients with CRC. Longitudinal research should assess the effect of other factors (life style, health behaviors, psychological factors, etc.) on QOL. The increasing number of cancer survivors has long-term needs for nursing care which note multi-dimensional aspects of QOL. This study demonstrates the strength of the relationship between socio-demographic and clinical factors and generic and specific QOL in patients with CRC. There are nine socio-demographic and clinical factors that are significant predictors of QOL in patients with CRC which should be considered in treatment and care of patients.
| » Acknowledgments|| |
We wish to thank Social Determinants of Health Research Center and Gastrointestinal and Liver Diseases Research Center in Guilan for their advice and support of this project. Also, we offer our special thanks to Ms. Fatemeh Javadi for proofreading the manuscript.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7]