Analysis of sleep quality, disease uncertainty, and psychological tolerance in patients undergoing chemotherapy for digestive tract malignancies

Abstract

BACKGROUND

Colorectal cancer is the second leading cause of cancer-related deaths among digestive tract malignancies, following gastric cancer. Sleep is of great significance for maintaining human health. The incidence of sleep disorders in patients with cancer is approximately twice that observed in the general population. Lack of sleep can prolong hospital stays, increase the likelihood of infection, and increase mortality rates. Therefore, studying the factors related to sleep quality is significant for improving the quality of life of patients with malignant tumors of the digestive tract.

AIM

To investigate the relationships among sleep quality, disease uncertainty, and psychological resilience in patients undergoing chemotherapy for digestive tract malignancies.

METHODS

A total of 131 patients with malignant digestive tract tumors who were treated at Hefei BOE Hospital between April 2021 and September 2022 were selected as research participants. Based on their Pittsburgh Sleep Quality Index (PSQI) scores, participants were divided into either the sleep disorder group (PSQI score > 7) or the normal sleep group (PSQI score ≤ 7). The clinical data—together with the Mishel Uncertainty in Illness Scale for Adults (MUIS-A) and Connor-Davidson Resilience Scale (CD-RISC) scores—were compared.

RESULTS

In this study, 78 (59.54%) patients with digestive tract malignancies developed sleep disorders after chemotherapy. Sleep disorder incidence was higher in patients with colorectal cancer than in those with gastric and esophageal cancers (P < 0.05). The total MUIS-A score and those for each item in the sleep disorder group were higher than those in the normal sleep group. The total CD-RISC score and those for each item in the sleep disorder group were lower than those in the normal sleep group (P < 0.05). The PSQI scores of patients with malignant digestive tract tumors were positively correlated with the scores for lack of disease information, disease uncertainty, and unpredictability in the MUIS-A and negatively correlated with the scores for tenacity, self-improvement, and optimism in the CD-RISC (P < 0.05).

CONCLUSION

Patients undergoing chemotherapy for digestive tract malignancies are prone to sleep problems related to disease uncertainty and psychological resilience. Therefore, interventions can be implemented to improve their sleep quality.

Key Words: Malignant digestive tract tumor, Chemotherapy, Sleep quality, Disease uncertainty, Psychological resilience

Core Tip: The aim of this study was to investigate the relationships between sleep quality, disease uncertainty, and psychological resilience in patients undergoing chemotherapy for digestive tract malignancies. Overall, 78 (59.54%) of these patients developed sleep disorders after chemotherapy. Sleep disorder incidence was higher in patients with colorectal cancer than in those with gastric and esophageal cancers. These data suggest that patients undergoing chemotherapy for digestive tract malignancies are prone to sleep problems. Therefore, intervention measures should be implemented to improve their sleep quality.

INTRODUCTION

In recent years, the cancer incidence rate has been increasing annually and is expected to grow by 70% over the next 20 years. Cancer is the main cause of death worldwide, accounting for 13% of global mortality. Colorectal cancer is the second leading cause of cancer-related deaths among digestive tract malignancies, following gastric cancer[1]. According to Global Cancer Observatory 2018 data, the mortality rates of colorectal and gastric cancers have reached 9.2% and 8.2%, respectively. Currently, the quality of life of patients with advanced gastrointestinal malignant tumors remains low, and improving their quality of life is of great significance. Sleep is important for maintaining human health, especially for promoting early recovery and improving patients’ quality of life[2]. The incidence of sleep disorders in patients with cancer is approximately twice that observed in the general population. Lack of sleep can prolong hospital stays, increase the likelihood of infection, and increase mortality rates. Therefore, studying the sleep quality factors is significant for improving the quality of life of patients with malignant tumors of the digestive tract[3].

Disease uncertainty refers to an individual's lack of judgment in the face of stressful disease-related events, whereas psychological resilience is a new concept derived from international psychology. It refers to the individual's adaptation process in the face of threats, tragedy, trauma, adversity, or other major pressures; that is, the ability to adapt and rebound from difficult experiences and the protection mechanisms that develop after encountering stress[4]. Previous studies[5] have found that patients with breast cancer undergoing post-operative chemotherapy experienced a high degree of psychological distress, which is closely related to disease uncertainty. However, few reports exist on the relationship between sleep quality, psychological resilience, and disease uncertainty in patients undergoing chemotherapy for gastrointestinal cancer more specifically. Therefore, this study analyzed the relationship between sleep quality, disease uncertainty, and psychological resilience in patients with malignant tumors of the digestive tract undergoing chemotherapy.

MATERIALS AND METHODS

Participants

A total of 131 patients with gastrointestinal malignant tumors who were treated with chemotherapy at Hefei BOE Hospital from April 2021 to September 2022 were selected as study participants. The inclusion criteria were as follows: (1) Patients diagnosed with malignant tumors of the digestive tract through pathological tissue examination combined with clinical symptom examination; (2) having clear consciousness and good cognitive status and having received chemotherapy for gastrointestinal malignant tumors (chemotherapy frequency ≤ 6 times in 120 patients and > 6 times in 11 patients); and (3) possessing certain language communication skills and signing a mandatory informed consent form along with their family members. The exclusion criteria are as follows: (1) Individuals with concomitant mental disorders and cognitive impairment; (2) inability to eat orally or simultaneously receive radiation therapy due to other reasons; (3) having an expected survival time of < 3 months or with two or more types of tumor lesions; and (4) recently experiencing significant traumatic events. Among the selected participants, 100 were male and 31 were female with ages ranging from 47 to 93 years old. Regarding disease type, 22 patients had rectal cancer, 13 had colon cancer, 33 had gastric cancer, and 63 had esophageal cancer. Regarding educational level, 61 patients had a junior high school education and below, and 70 had a high school education and above. Regarding place of residence, 81 patients lived in urban areas and 50 lived in rural areas.

Methods

To assess participants’ sleep quality, the Pittsburgh Sleep Quality Index (PSQI)[6] was used. The PSQI scale comprises 18 items scored on seven dimensions (sleep quality, time to fall asleep, sleep time, sleep efficiency, sleep disorders, hypnotic drugs, and daytime dysfunction), with each item ranging from 0 to 3 points. The cumulative PSQI total score is the sum of these seven components, yielding a total score of 0–21 points. Higher scores indicate poorer sleep quality. The Cronbach's coefficient of the scale is 0.831. In this study, a total score of PSQI > 7 was set as a reference value for sleep quality issues in hospitalized patients with digestive tract malignant tumors undergoing chemotherapy. A score of ≤ 6 indicates satisfactory sleep quality, while a higher score indicates poorer sleep quality during hospitalization. Specifically, a score of 7–10 indicates mild sleep disorder; 11–15, moderate sleep disorder; and 16–21, severe sleep disorder.

To evaluate disease uncertainty, the Chinese version of the Mishel's Uncertainty in Illness Scale Adult (MUIS-A)[7] was used to assess the degree of disease uncertainty. The MUIS-A includes four dimensions—namely, lack of disease information, disease uncertainty, complexity, and unpredictability—totaling 33 items, scored on a 5-point Likert scale, ranging from "very dissatisfied" (1) to "very satisfied" (5). The cumulative score range is 32–160 points, with higher scores indicating greater disease uncertainty. Specifically, disease uncertainty can be divided into high (117.5–160 points), medium (74.8–117.4 points), and low levels (32–74.7 points). The Cronbach's coefficient of the MUIS-A scale (Chinese version) is 0.795.

To evaluate psychological resilience, the Connor Davisson Resilience Scale (CD-RISC)[8] was used. The scale includes the following three dimensions: resilience (13 items), self-improvement (8 items), and optimism (4 items), totaling 25 items, scored on a 5-point scale ranging from 0–4 points, with a total score of 0–100 points. Higher scores indicate better psychological resilience. The CD-RISC has acceptable internal consistency, with a Cronbach's coefficient of 0.914.

Based on the PSQI results and set reference value, a sleep disorder group (PSQI score > 7 points) and normal sleep group (PSQI score ≤ 7 points) were formed. Clinical data from the two groups were collected, including sex, age, educational level, place of residence, chemotherapy regimen, chemotherapy frequency, pain level (pain visual analogue score; 0–3 points = mild, 4–6 points = moderate, and 7–10 points = severe), self-rating anxiety scale (SAS) score, self-rating depression scale (SDS) score, and presence or absence of noise in the ward. Further, SAS and SDS both comprise 20 items, with scores ranging from 0 to 100 points and cutoff values of 50 for both. The index score is 53 points; the higher the score, the more severe the anxiety and depression. The standard for judging the noise level in the ward was whether the noise intensity, as monitored by a sound level meter, was greater than 50 dB in the daytime, or greater than 35 dB at night.

Observation indicators

Patient data were analyzed as follows: (1) Clinical data between the sleep disorder and normal sleep groups were compared; (2) Disease uncertainty and psychological resilience between the sleep disorder and normal sleep groups were compared; (3) The correlations among PSQI, MUIS-A, and CD-RISC scores were analyzed; and (4) The risk factors for sleep disorders in patients with gastrointestinal malignant tumors undergoing chemotherapy were analyzed.

Statistical methods

The data were processed using SPSS 20.0, and the count data were presented in the form of n (%), χ², Fisher's exact probability method, econometric data presented in the form of (mean ± SD), a t-test between independent samples, a one-way analysis of variance, and an LSD-t-test. Pearson correlation was used for correlation analysis, and logistic regression analysis was used to identify the risk factors for sleep disorders in patients with gastrointestinal malignancies undergoing chemotherapy. P < 0.05 was set as the statistically significant difference.

RESULTS

Sleep quality survey results

Overall, 78 patients (59.54%, 78/131) undergoing chemotherapy for gastrointestinal malignant tumors had sleep disorders. Among the disorders, 41 cases were mild, 26 were moderate, and 11 were severe. The specific results are presented in Table 1. Differences in PSQI scores among the patients were observed, with patients with gastric and esophageal cancer having higher PSQI scores than those with colorectal cancer. The incidence of sleep disorders in patients with colorectal cancer was significantly higher (P < 0.05) than that observed in patients with gastric or esophageal cancer (Table 1).

Table 1 Sleep quality survey results of gastrointestinal malignant tumor chemotherapy patients.

Cancer types	n	PSQI score (points)	Number of sleep disorders				Incidence of sleep disorders (%)
			Mild	Moderate	Severe	Total
Gastrointestinal malignant tumor	131	10.52 ± 1.07	41	26	11	78	59.54
Rectal cancer	22	9.31 ± 0.96	9	7	3	19	86.36
Colon cancer	13	9.19 ± 0.94	6	4	1	11	84.62
Gastric cancer	33	11.18 ± 1.46a,b	8	5	3	16	48.48a,b
Esophageal cancer	63	10.87 ± 1.72a,b	18	10	4	32	50.79a,b
F/χ2		11.621				13.639
P value		< 0.001				0.003

^aP < 0.05, compared with rectal cancer; ^bP < 0.05, compared with colon cancer. PSQI: Pittsburgh Sleep Quality Index.

Comparison of data between sleep groups

No statistically significant differences in sex, educational level, place of residence, and chemotherapy regimen were observed between the sleep disorder and normal sleep groups (P > 0.05). By contrast, the age, SAS score, SDS score, and proportion of noise in the ward were higher in the sleep disorder group compared to the normal sleep group. Moreover, the frequency of chemotherapy and pain were higher compared to the normal sleep group (P < 0.05; Table 2).

Table 2 Comparison of data between the sleep disorder group and the normal sleep group.

Variables	Group	Sleep disorders group (n = 78)	Normal sleep group (n = 53)	χ2/t	P value
Sex	Male	62 (79.49)	38 (71.70)	1.060	0.303
	Female	16 (20.51)	15 (28.30)
Age	-	68.74 ± 6.95	64.82 ± 6.56	3.241	< 0.001
Educational level	Junior high school and below	36 (46.15)	25 (47.17)	0.013	0.909
	High school and above	42 (53.85)	28 (52.83)
Residence	Town	48 (61.54)	33 (62.26)	0.007	0.933
	Rural	30 (38.46)	20 (37.74)
Chemotherapy regimen	FOLFOXIRI	45 (57.69)	32 (60.38)	0.094	0.759
	FOLFOX	33 (42.31)	21 (39.62)
Chemotherapy frequency	≤ 6	68 (87.18)	52 (98.11)	4.905	0.027
	> 6	10 (12.82)	1 (1.89)
Pain level	Mild	68 (85.90)	52 (98.11)	-	0.0361
	Moderate	9 (12.82)	1 (1.89)
	Severe	1 (1.28)	0 (0)
SAS score	-	57.43 ± 5.86	46.62 ± 4.58	11.286	< 0.001
SDS score	-	58.17 ± 5.69	44.23 ± 4.75	14.689	< 0.001
Ward noise	Yes	30 (38.46)	10 (18.87)	5.712	0.017
	No	48 (61.54)	43 (81.13)

¹Indicates using Fisher's exact probability method. SAS: Self-rating anxiety scale; SDS: Self-rating depression scale.

Comparison of MUIS-A scores between sleep groups

The lack of disease information, uncertainty, complexity, unpredictability, and overall score for MUIS-A were higher in the sleep disorder group compared to the normal sleep group (P < 0.05; Table 3).

Table 3 Comparison of Mishel Uncertainty in Illness Scale for Adults scores between sleep disorder group and normal sleep group (mean ± SD).

Group	Lack of disease information	Disease uncertainty	Complexity	Unpredictability	Total score
Sleep disorders group (n = 78)	16.57 ± 1.68	46.25 ± 4.72	24.75 ± 2.54	10.13 ± 1.16	97.76 ± 9.82
Normal sleep group (n = 53)	13.26 ± 1.57	30.57 ± 3.26	16.54 ± 1.79	8.15 ± 0.83	68.53 ± 6.90
t	11.362	21.007	20.338	10.699	18.743
P value	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001

Comparison of CD-RISC scores between sleep groups

The dimensions of resilience, self-improvement, optimism, and total score of the sleep disorder group's CD-RISC were all lower compared to the normal sleep group (P < 0.05; Table 4).

Table 4 Comparison of Connor-Davidson Resilience Scale scores between sleep disorder group and normal sleep group (mean ± SD).

Group	Resilience	Self-improvement	Optimistic	Total score
Sleep disorders group (n = 78)	25.48 ± 2.63	17.15 ± 1.78	5.71 ± 0.61	48.32 ± 4.96
Normal sleep group (n = 53)	28.63 ± 2.97	18.96 ± 1.93	6.34 ± 0.65	53.93 ± 5.46
t	6.383	5.520	5.650	6.099
P value	< 0.001	< 0.001	< 0.001	< 0.001

The correlation analysis between PSQI score and MUIS-A and CD-RISC scores in the study patients revealed that their PSQI scores were positively correlated with disease information deficiency, disease uncertainty, and unpredictability score in MUIS-A; however, the PSQI score was not significantly correlated with complexity (P > 0.05). Additionally, the PSQI score was negatively correlated with the resilience, self-improvement, and optimism dimensions of CD-RISC (P < 0.05; Table 5).

Table 5 Correlation between Pittsburgh Sleep Quality Index score and Mishel Uncertainty in Illness Scale for Adults and Connor-Davidson Resilience Scale scores in chemotherapy patients with gastrointestinal malignant tumors.

Variables		PSQI
		r	P value
MUIS-A score	Lack of disease information	0.583	< 0.001
	Disease uncertainty	0.422	0.008
	Complexity	0.169	0.114
	Unpredictability	0.426	0.006
CD-RISC score	Resilience	-0.579	< 0.001
	Self-improvement	-0.613	< 0.001
	Optimistic	-0.281	0.021

PSQI: Pittsburgh Sleep Quality Index; MUIS-A: Mishel Uncertainty in Illness Scale for Adults; CD-RISC: Connor-Davidson Resilience Scale.

An analysis of the factors influencing sleep disorders in patients undergoing chemotherapy for gastrointestinal malignant tumors using multivariate logistic regression analysis revealed that the SAS and SDS scores, ward noise, and MUIS-A score were independent risk factors for sleep disorders in these patients, while the CD-RISC score was a protective factor (P < 0.05; Table 6).

Table 6 Analysis of Factors Influencing Sleep Disorders in Chemotherapy Patients with Gastrointestinal Malignant Tumors.

Factors	β	SE	Wald χ2	OR	P value	95%CI
Age	0.353	0.276	1.636	1.423	0.202	0.829-2.445
Chemotherapy frequency	0.255	0.184	1.921	1.290	0.167	0.900-1.851
Pain level	0.457	0.273	2.802	1.579	0.095	0.925-2.697
SAS score	0.291	0.115	6.403	1.338	0.012	1.068-1.676
SDS score	0.284	0.118	5.793	1.328	0.017	1.054-1.674
Ward noise	0.365	0.176	4.301	1.441	0.039	1.020-2.034
MUIS-A score	0.357	0.148	5.819	1.429	0.016	1.069-1.910
CD-RISC score	-0.426	0.106	16.151	0.653	< 0.001	0.531-0.804

MUIS-A: Mishel Uncertainty in Illness Scale for Adults; CD-RISC: Connor-Davidson Resilience Scale; SAS: Self-rating anxiety scale; SDS: Self-rating depression scale.

DISCUSSION

Gastrointestinal malignancies include gastric and rectal cancers, and for patients with these malignancies, chemotherapy is the main treatment; however, it can cause serious adverse gastrointestinal reactions[9]. Most patients undergoing chemotherapy have sleep disorders, but the patients themselves do not attach sufficient importance to this problem. Moreover, various discomforts caused by chemotherapy drugs can lead to physical and mental exhaustion, resulting in cancer patients not being proactive about dealing with their sleep disorders, and potentially even exacerbating them[10]. A high level of psychological resilience can fully tap into patients’ inherent potential, enabling them to actively and optimistically face the adverse effects of their illness, actively cooperate with the treatment and nursing support, actively seek help, and guide them toward a positive coping style[11]. However, the uncertainty of the disease can cause confusion about the future and reduce confidence in treatment, thus affecting the treatment’s effectiveness. Therefore, exploring whether disease uncertainty and psychological resilience negatively impact the sleep quality of patients undergoing chemotherapy for malignant gastrointestinal tumors is necessary.

Kang et al[12] reported that the sleep disorder rate of hospitalized patients with digestive tract malignant tumors undergoing chemotherapy was 58.3%, with a total PSQI score of (11.73 ± 3.98) points for affected patients. In this study, the incidence of sleep disorders was 59.54%, which was slightly higher than in the previous study, indicating a higher overall incidence rate, especially for patients with colorectal cancer, whose incidence of sleep disorders was higher than those with gastric and esophageal cancer. Patients experience persistent and subjective fatigue; this results in a lack of endurance in activities, low concentration, weakness, and decreased interest, which precipitates severe psychological stress and even affects normal sleep, thus decreasing their quality of life. Moreover, poor sleep quality can affect patients' physical recovery and reduce their enthusiasm to participate in daily life. It may also affect the establishment of new synaptic connections between brain cells, which reduces memory and attention, thus forming a vicious cycle in the long term. Therefore, closely monitoring patients’ sleep status, providing relevant interventions and guidance, and promoting patient prognosis after chemotherapy are all necessary[13].

In this study, the total score and sub-scores of the MUIS-A in the sleep disorder group were higher than those in the normal sleep group, while the total score and sub-scores of the CD-RISC in the sleep disorder group were lower than those in the normal sleep group. This indicates that patients with sleep quality problems in this study have high disease uncertainty and low psychological resilience. Disease uncertainty refers to an individual’s inability to determine things related to the disease, which belongs to the cognitive category and accompanies symptoms, diagnosis, treatment, and prognosis. Uncertainty exists when the patient’s disease status is unpredictable. Disease uncertainty not only affects the patient's ability to seek disease-related information and make appropriate medical decisions but may also cause anxiety, affect the patient's psychological adaptation ability, and impact their quality of life. A decrease in hope and disease response ability, as well as in sleep quality, accelerates disease progression[14]. Psychological resilience refers to the adaptability of patients to major biochemical pressures, such as difficulties, adversity, trauma, threats, and potential disease treatment problems. Coping successfully with stress is a positive psychological quality and forms a positive force for such individuals. Patients with high psychological resilience have lower stress response ability and can better adapt to and manage life difficulties. Potential problems that patients with low psychological resilience may face regarding treatment following disease diagnosis include higher stress response, difficulty in actively adapting to high-risk environments, and difficulty in adopting a positive attitude to face difficulties and setbacks, which may decrease sleep quality[15].

This study found that the PSQI scores of patients with malignant gastrointestinal tumors were positively correlated with a lack of disease information, disease uncertainty, and unpredictability scores in the MUIS-A, whereas the PSQI score was negatively correlated with the resilience, self-improvement, and optimism dimensions of CD-RISC. This indicates that sleep quality in these patients is associated with high disease uncertainty and low psychological resilience. Patients receiving chemotherapy after admission may experience a sense of unfamiliarity with their medical environment. When facing a life-threatening diagnosis of cancer, their lack of medical knowledge, the difficulty and complexity of the disease itself and its treatment methods, the unpredictability of the development process and prognosis, and the patient's lack of ability to determine and relate to things about the future may all precipitate a sense of disease uncertainty. Additionally, patients undergoing chemotherapy may experience adverse physical and psychological reactions, and the appearance of symptoms can negatively impact psychological resilience. These patients often experience problems such as pain, numbness, decreased appetite, and nausea. As their physical and mental problems increase, their sense of disease uncertainty also increases. This is not conducive to physical and mental adaptation and development, lowering levels of psychological resilience and worsening sleep quality[16].

Previously, Wang et al[17] reported that the psychological resilience of patients with gastrointestinal cancer before chemotherapy was negatively correlated with disease uncertainty (r = -0.40) and the coping style of yielding (r = -0.44) and positively correlated with the coping style of facing (r = 0.41). Disease uncertainty can affect disease progression, psychological adjustment, sleep quality, and quality of life. For example, Liu et al[18] found a negative correlation between psychological/emotional burden, care burden, treatment burden, and total burden with psychological resilience in patients undergoing chemotherapy for lung cancer (β = -0.13–1.09). Hence, the combined effects of disease uncertainty and psychological resilience may influence sleep quality in patients undergoing chemotherapy for gastrointestinal malignancies. Multivariate logistic regression analysis conducted by Kang et al[12] revealed that pain level, anxiety, concern, and ward noise were independent risk factors for sleep disorders in patients with gastrointestinal malignancies undergoing chemotherapy. By performing multivariate logistic regression analysis, this study found that the SAS and SDS scores, ward noise, and MUIS-A score were independent risk factors for sleep disorders among these patients, whereas the CD-RISC score was a protective factor, indicating similar and divergent findings. Anxiety and concern may cause sleep disorders in such patients, and they may experience negative emotions because of concerns regarding their disease and its economic burden, which can adversely affect disease treatment.

Thus, medical workers should actively strengthen communication and interaction with patients so that they can face the disease rationally and actively cooperate with treatment. Psychological professionals may also assist in improving sleep disorders during chemotherapy if necessary[19,20]. Disease uncertainty can affect a patient's coping ability. Patients with low levels of disease uncertainty have better psychological adjustment ability, higher psychological resilience, lower stress, and are more willing to adopt positive coping methods, thereby achieving positive results and improving sleep quality and quality of life[21,22]. Patients with high disease uncertainty owing to a lack of professional knowledge have unpredictable disease and treatment outcomes. They can only choose to accept their fate and passively respond to the threat of disease uncertainty, resulting in poor adaptability, negative outcomes, and poor sleep quality[23]. Therefore, the uncertainty of disease and psychological resilience significantly impact the sleep quality of patients with malignant digestive tract tumors undergoing chemotherapy. In medical care, helping patients understand the purpose and significance of treatment and nursing, communicating effectively with them and their families in a timely manner regarding treatment and examination results, and providing detailed and accurate explanations for their questions are all necessary. When patients encounter problems, they should be promptly and fully resolved, and follow-up should be performed after discharge[24].

This study has some limitations. Owing to the relatively small sample size and the sample being from a single location, representative only of patients in that hospital, the generalizability of the findings and extrapolation of conclusions is limited.

CONCLUSION

In summary, the sleep quality of patients with malignant gastrointestinal tumors undergoing chemotherapy is low and closely correlated with disease uncertainty and psychological resilience. Corresponding intervention measures can be implemented to improve these patients’ sleep quality.