Evaluating health-related quality of life in gastric cancer patients in Suzhou, China

Introduction

Gastric cancer is one of the most common cancers in the world and is a serious threat to human health. In 2018, statistics from the International Agency for Research on Cancer indicated that there were approximately one million new cases and 784,000 deaths from gastric cancer worldwide. Moreover, gastric cancer ranked fifth in incidence and third in mortality rates of all malignant tumors (1). Although the global incidence and mortality of gastric cancer appear to be decreasing, the rates in China are still at a high level. According to statistics released by the National Cancer Registry Center in 2015, the incidence and mortality of gastric cancer in China ranks second among malignant tumors (2). According to the incidence and death of malignant tumors in Suzhou citizens in 2018 officially released by the Suzhou Municipal Health Commission, there were 23,122 new cases of malignant tumors in Suzhou, among which gastric cancer ranked the third, accounting for 11.72% (only second to lung cancer, accounting for 18.25%, and colorectal cancer, accounting for 11.98%). A total of 14,461 malignant tumor deaths occurred, of which gastric cancer accounted for 15% of all malignant tumors, ranking second only to lung cancer (26%). In recent 10 years (2009 to 2018), the mortality rate of malignant tumors in Suzhou has been rising steadily (3).

With the continuing advances in medical diagnosis and treatment technologies, overall survival from gastric cancer has significantly improved, but the various psychological and social problems that arise as a consequence of treatment can affect patients’ quality of life. Health-related quality of life (HRQOL) has become an important component of the evaluation of clinical efficacy and prognosis in the treatment of gastric cancer.

HRQOL is a subjective, multidimensional concept that includes physical, functional, and mental/emotional health factors related to an individual’s health (4). Physical well-being refers to the patient’s physical state and any treatment side effects; functional health refers to whether a patient’s ability to perform daily activities and take care of themselves is affected; emotional aspect refers to whether the patient's mental state and mood are affected. Through the influence on these three aspects, the quality of life of patients will be more or less decreased.

Recently, the use of HRQOL as a clinical outcome measure for cancer treatment has been growing rapidly, reflecting differences in the health status of gastric cancer patients with different clinical conditions and socio-economic characteristics at different stages of the disease (5). Many current studies have shown that the quality of life of patients with gastric cancer is impaired and significantly lower than that of non-cancer people (6-8). There is a need for better monitoring of patients’ quality of life to support clinical and public health decision-making. In this way, we can look for factors that affect quality of life and help improve quality of life for cancer patients.

Several instruments measure HRQOL, such as the EuroQol five-dimension (EQ-5D) (9), the short-form six-dimension survey (SF-6D) (10), the health utilities index (HUI) (11) and the European Organization for the Research and Treatment of Cancer quality of life questionnaire (EORTC-QLQ-C30) (12). The EORTC-QLQ-C30 was designed for cancer patients in general and the EORTC-QLQ-STO22, developed from it, was the novelist measurement to assess the HRQOL of patients with gastric cancer specifically (13). Of these instruments, the EQ-5D is the simplest, the most widely used and has shown both satisfactory reliability and validity in general patient populations in China (14-17). The EQ-5D, a multi-dimensional evaluation scale, now has two versions: three-level EQ-5D questionnaire (EQ-5D-3L) and five-level EQ-5D questionnaire (EQ-5D-5L). The 5L is a new version for describing and evaluating HRQOL. Compared to its predecessor EQ-5D-3L, 5L expands the number of combined health states and shows a lower ceiling effect and a higher sensitivity (18-20). Extensive research has been conducted using the EQ-5D-5L questionnaire to assess HRQOL in different types of patients, including head-and-neck cancer (21), breast cancer (22), lung cancer (23), and colorectal cancer (24), but only a few studies have focused on gastric cancer patients in China (25-27). This study used the EQ-5D-5L to investigate the HRQOL of gastric cancer patients and evaluated the influencing factors on patients’ perceived quality of life.

We present the following article in accordance with the SURGE reporting checklist (available at https://dx.doi.org/10.21037/apm-21-1599).

Methods

Study participants

A cross-sectional questionnaire survey was administered to patients in the First Affiliated Hospital of Soochow University from December 2019 to December 2020. Eligibility criteria were as follows: (I) over 18 years old, (II) a pathological diagnosis of gastric cancer, (III) cognitive integrity, and (IV) adequate reading and communication skills. Patients were excluded if they could not understand the survey questions or if they failed or refused to give written consent. Subsequently, 243 patients (170 males and 73 females) were interviewed face-to-face by trained interviewers. This study has been approved by the Ethics Committee of the First Affiliated Hospital of Soochow University (No. 98, 2021) and followed the tenets of the Declaration of Helsinki (as revised in 2013). Informed consent was taken from all the patients.

Measurement of HRQOL

In this study, HRQOL was estimated by the EQ-5D-5L, which has an established Chinese version. The EQ-5D instrument has demonstrated satisfactory validity and reliability in both general and patient populations in mainland China. It consists of five dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Each dimension has five levels: 1, no problems; 2, slight problems; 3, moderate problems; 4, severe problems; and 5, extreme problems. The patients were asked to select their perceived severity level from the 1 to 5 scale for different statements. As a result, a total of 3,125 (5⁵) statements can be combined in this system. Each statement can then be converted to a health utility score using the Chinese EQ-5D-5L value set (28). The higher the utility score, the better the quality of life. When all five dimensions are at level 1, the patient is deemed to be in a state of full health (11111), and the corresponding utility score is 1, which represents the upper limit of the utility value. The lowest is −0.391, which represents the worst health status (55555).

Clinical and socioeconomic characteristics

Data on the clinical features of patients were collected through the medical records, including the stage of gastric cancer [I, II, III, IV; TNM pathological staging according to the American Joint Committee on Cancer (AJCC) 7th edition], treatment (surgery, chemotherapy, or combined surgery and chemotherapy), and complications (e.g., hypertension or diabetes). The socioeconomic characteristics of the respondents were collected from the questionnaire survey, which included gender, age, education level, marital status, and medical insurance. Other data collected concerned lifestyle habits, such as a history of smoking or drinking.

Statistical analysis

The characteristics and HRQOL of gastric patients assessed by the EQ-5D-5L are summarized using descriptive statistics. The mean and standard deviations (SDs) are used for continuous variables, whereas frequencies and percentages are used for categorical variables. As the EQ-5D-5L utility scores of respondents followed a non-normal distribution, nonparametric test analyses were performed to explore the differences in the utility scores of patients with different characteristics, including the Wilcoxon rank-sum test for comparison of two independent samples and a Kruskal-Wallis analysis for multiple independent samples. We subsequently established a Tobit regression model between the utility scores and the independent variables that were statistically significant (P<0.05) in the nonparametric test analyses.

There is a common ceiling effect in EQ-5D instruments when a large number of patients report the highest health state, leading to some utility scores being censored at 1.0 (29-31). When the utility score is used as the dependent variable for statistical modeling, some traditional statistical methods that require the dependent variable to follow a normal distribution are no longer applicable. Therefore, when it comes to censored data, the use of the Tobit regression model is advised (32-34). EpiData3.0 (http://www.epidata.dk/links.htm) was used to establish the database, and SAS (version 9.4, 2014, SAS Inc., Cary, NC, USA) was used for the statistical analysis.

Results

Problems reported in the five dimensions of EQ-5D-5L

Of the 243 patients in this research, 24.7% reported no problems in any of the five dimensions. Problems with pain and discomfort were the most frequently reported (64.2%), which included slight, moderate, severe, and extreme ratings. Problems with anxiety and depression accounted for 35.4%, and self-care problems ranked the lowest (23.9%), as shown in Table 1.

Table 1 Problems reported by respondents in the five dimensions of the EQ-5D-5L
Full table

Overall description of patient scores

On the whole, the utility scores of gastric cancer patients in this study were encouraging. Almost 25% of patients reported no problem in any EQ-5D domain, and their utility score was 1.0. The mean score was 0.810, and the median was 0.893. The distribution of the utility scores tended towards the right (higher values), as shown in Figure 1.

Figure 1 Distribution of the EQ-5D-5L utility scores of patients with gastric cancer. EQ-5D-5L, five-level EuroQol five-dimensional questionnaire.

Comparison of the utility scores in respondents with different characteristics

Table 2 presents the socioeconomic characteristics of the participants in this study. The mean age of the patients was 62.1 years, and 61.7% were over 60 years old; males accounted for 70%; the majority lived with their spouses (95.1%), and 41.6% were covered by urban residents’ health insurance. More than half of the patients reported that they had not smoked (57.2%) or drunk 68.3%) in recent months. Among the 243 patients, only a small percentage (26.3%) had a family history of cancer.

Table 2 Comparison of the health utility values of gastric cancer patients with socioeconomic characteristics
Full table

Among the clinical characteristics, we found that most gastric patients were at stage III (41.2%) and stage IV (23.5%). All patients had received medical treatment: 43.2% had received surgery, 14% had received chemotherapy alone, and 42.8% had received combined surgery and chemotherapy. There were 82 patients (33.7%) who reported that the time between this survey and their last treatment was less than 1 week, while 74 patients (30.5%) reported an interval of more than 1 month, as shown in Table 3. Many patients reported having no complications: 57.6% had neither diabetes nor hypertension.

Table 3 Comparison of the health utility values of gastric cancer patients with clinical characteristics
Full table

Results of univariate analysis

As shown in Tables 2,3, those patients who did not have health insurance, had a history of alcohol use, a family history of cancer, received surgery only, or had an interval of less than 1 week between this survey and their last treatment reported lower utility scores (P<0.05). Meanwhile, no significant differences in the utility scores were found in gender, age, marital status, education levels, complications, or tumor stage (P>0.10).

Multivariate analysis results

The Tobit regression model confirmed that health insurance, family history, and treatment were significantly associated with the EQ-5D-5L utility scores (P<0.05). However, after controlling for other factors, alcohol use and the interval between this survey and the last treatment became insignificant (Table 4).

Table 4 Results of the Tobit regression model on EQ-5D-5L index scores of patients
Full table

Discussion

With the change in medical models, the clinical treatment of gastric cancer no longer simply pursues the extension of life but also pays more attention to improvements in quality of life (35). In this cross-sectional study, we measured the HRQOL of gastric cancer patients using the Chinese version of the EQ-5D-5L scale and explored the factors that influence patients’ quality of life. To the best of our knowledge, only a few studies have assessed the HRQOL of gastric cancer patients in mainland China. HRQOL results can be used to calculate quality-adjusted life years and are essential indicators for health economic evaluations. In addition, we examined five dimensions, including physical and mental problems, which can guide medical staff in targeted intervention measures to improve the quality of life for patients. Furthermore, this study also detected relationships between utility scores and clinical and socioeconomic factors that can help clinicians and policy decision-makers allocate resources more effectively.

In this study, we found that pain/discomfort was the most frequently reported problem among patients (64.2%, all levels included) in the five health dimensions. The pain/discomfort experienced may have been due to abdominal discomfort from the cancer itself, the pain following surgery, or the side effects caused by chemotherapy drugs, such as gastrointestinal discomfort, neurovirulence, and hair loss (36,37). Our results highlight the importance of paying more attention to the patient’s pain during diagnosis and treatment. If the side effects of chemotherapeutic drugs are severe, other drugs with similar efficacy can be selected as an alternative. Additionally, anxiety/depression was another commonly reported problem (35.4%, all levels included) in the five dimensions. There is no doubt that psychological problems are significant among cancer patients (38-40). With the extension of treatment time and the increase in treatment costs, the psychological burden for patients becomes greater. Therefore, we should pay more attention to the psychological burden experienced by patients and find strategies to relieve anxiety, improve depressed mood, and help patients build up the confidence to combat the disease and cope with treatment.

Among the socioeconomic factors, we found that whether patients had insurance or not had an impact on their utility scores. The HRQOL of patients who had any health insurance was significantly higher than those who did not. The cost of cancer patients’ medical treatment is quite expensive, but with universal medical insurance coverage, patients only need to pay a part of the cost, which greatly reduces their financial burden. As for the factor of medical insurance, clinicians can help patients finish the reimbursement procedures and choose those drugs with larger reimbursement ratio as far as possible, so as to reduce the economic burden of patients. Apart from this, family history was also an important negative factor. It may be that family history interferes with the patient’s psychological state, leading them to worry about the health status of other family members. For this factor, we can calm patients' anxiety, explain the significance of family history, and suggest that the family members have regular medical examinations. However, the Tobit regression model showed that the correlations between gender, age, educational level, and lifestyle with quality of life were not statistically significant. Nevertheless, further investigations of these factors are warranted. In terms of overall scores, our results showed that the HRQOL of female patients was significantly lower than that of male patients. This result is in accord with findings from Yun et al. (41) and Michelson et al. (42). Female patients may be more pessimistic and have a lower tolerance for anxiety, depression, and other negative emotions, thus affecting treatment compliance and quality of life. Some studies have also shown that age is related to the quality of life of patients who have gastric cancer, with older patients reporting a worse quality of life (41,43).

In the Tobit regression, the treatment also showed a significant association with the utility scores of gastric cancer patients. Patients who had undergone surgery often had lower HRQOL scores, which may be due to the increased pain and discomfort arising from surgical procedures. On the contrary, patients receiving routine chemotherapy are generally stable with little disruption to their normal lives. Gastric cancer surgery is divided into traditional open surgery and laparoscopic minimally invasive surgery. For patients with gastric cancer, open surgery has great trauma and slow postoperative recovery while laparoscopic minimally invasive surgery has the advantages of minimally invasive, less bleeding and quick recovery (44). Therefore, in the surgical treatment of gastric cancer, doctors should choose laparoscopic surgery as far as possible, which is beneficial to improve the quality of life. There is also some debate about the association between quality of life and the stage of gastric cancer. Some previous studies found that tumor stage had an important influence on the quality of life in patients with gastric cancer and that the HRQOL with stage IV was the poorest (45). But in this study, tumor stage was not significant in the multivariate analysis. We can find that the scores of patients in stage I were the poorest. This may be because patients in this stage were mostly found in general surgery and the interval between the surgery and this research was not long enough to allow for complete wound healing, and their daily activities were significantly affected. However, like many other studies (46,47), most cancer patients in our study were in advanced stages when first diagnosed. Therefore, attention should be paid not only to the tertiary prevention of cancer but also the primary or secondary prevention of gastric cancer. Early screening, early detection, and early treatment of high-risk groups are effective ways to improve the quality of life of gastric cancer patients.

There were several limitations in the study that deserve mention. First, the sample size was moderate because of limited resources, increasing the risk of type II errors. Second, this study was conducted in one hospital in Suzhou, so it was not a representative sample of China. Hence, future studies based on a larger and more representative sample of Chinese gastric cancer patients are warranted. Third, as a cross-sectional survey, our study was unable to establish a causal relationship between gastric cancer and HRQOL. Last but not least, the information regarding complications and family history was gathered by self-report rather than by medical testing, which may have influenced the accuracy of the results.

Conclusions

In summary, this research measured the HRQOL of gastric cancer patients by using the EQ-5D-5L and analyzed the influencing factors. Lower scores on the EQ-5D-5L were associated with a lack of health insurance, a family history of cancer, and receiving only surgical treatment. These results may assist in choosing an appropriate individualized treatment plan and strengthening interventions for the main influencing factors, thereby improving patients’ quality of life and prolonging their survival period.

Acknowledgments

We would like to express our gratitude to the study participants for their significant contribution to the data collection.

Funding: This study was supported by General Project of Natural Science Foundation of Higher Education Institutions of Jiangsu Province. Grant/Award Number: 20KJB320027.

Footnote

Reporting Checklist: The authors have completed the SURGE reporting checklist. Available at https://dx.doi.org/10.21037/apm-21-1599

Data Sharing Statement: Available at https://dx.doi.org/10.21037/apm-21-1599

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://dx.doi.org/10.21037/apm-21-1599). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study involving human participants were in accordance with the Declaration of Helsinki (as revised in 2013). The study was approved by the Ethics Committee of the First Affiliated Hospital of Soochow University of (No. 98, 2021) and informed consent was taken from all the patients.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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(English Language Editor: D. Fitzgerald)