Effects of Fatigue, Rumination Thinking and Sleep Quality on Hopelessness in Family Caregivers of Cancer Patients

doi:10.21203/rs.3.rs-2321950/v1

Background

The heavy care burden, long-term dependence of caring for cancer patients, and changing social roles puts family caregivers at high risk of mental disorders and hopelessness. This explored the relationship between fatigue, sleep quality, rumination, and hopelessness, and provides suggestions to maintain caregivers' mental health.

Methods

We investigated 536 family caregivers of cancer patients in three Grade-A hospitals in Liaoning Province who met the inclusion criteria on the Beck hopelessness scale (BHS), fatigue Scale-14 (FS-14), Nolen-Hoeksema ruminative responses scale (RRS), and Pittsburgh sleep quality index (PSQI). Data were analyzed with SPSS 26.0, and Amos 22.0 was used to fit the structural equation model.

Results

The family caregivers had a higher degree of hopelessness and fatigue, while sleep quality, and rumination were positively correlated with hopelessness (r = 0.483–0.906; P < 0.05). Fatigue and sleep quality can indirectly affect hopelessness through rumination thinking, while hopelessness has a direct effect on sleep.

Conclusions

There are multiple action paths between fatigue and sleep quality, rumination thinking, and hopelessness. Family caregivers‘ physical and mental health can be maintained and hopelessness avoided by improving sleep quality, alleviating fatigue, and psychological counselling.

Cancer

ruminative thinking

sleep quality

path analysis

family caregivers

Over the past decade, the incidence and mortality rates of cancers in China have both increased ^[1]. Cancers not only have a long course and poor prognosis, but also impose a heavy financial burden on general families. As such, the diagnosis and treatment of cancers will not only bring misery to the patients, but also exerts enormous physical and psychological pressure to their family caregivers^[2]. When these pressures cannot be effectively relieved, negative emotions gradually accumulate, causing individuals to lose hope in life, producing a sense of depression and hopelessness^[3]. In people, hopelessness is defined as a loss of interest in their own social environment, their own lives, and the people and things around them, resulting in a loss of confidence and a feeling of powerlessness and haplessness.

Hopelessness is a serious psychological disorder. The generation of hopelessness not only weakens the ability of family caregivers of cancer patients to care for patients, but also reduces their own quality of life. It can also result in serious adverse effects, such as auditory hallucinations, mental sensitivity, or some physical symptoms, and often continues until the patient terminates treatment or succumbs to their illness. In severe cases, hopelessness can lead to self-injury and suicide in family caregivers of patients with cancers^[4]. A sense of hopelessness also leads to a decline in individuals' ability to control their emotions. Thus, they become irritable, sensitive, and suspicious, and are more likely to engage in conflict with the people around them, which will lead to the breakdown of family relations, and sometimes conflicts with nurses or doctors^[5].

Experts and scholars have recently drawn attention to the importance of maintaining the physical and mental health of caregivers of patients with cancers. Some studies have found that such family caregivers have poor sleep quality and often feel physically and mentally fatigued^[6]. Other research has shown that caregivers of patients with cancers have high levels of ruminative thinking^[7]. Rumination refers to the process of passively indulging in negative thoughts and aggravating heavy negative emotions. Some studies have found that relatives and/or caregivers of seriously ill patients often engage in serious rumination, repeatedly falling into meaningless thinking, such as "why is my family so unfortunate", which will lead to anxiety and depression^[8]. In addition, long-term rumination thinking is closely related to the occurrence of some mental diseases^[9], and some studies have found that rumination thinking can reduce sleep quality. Many studies have shown that rumination thinking, fatigue, and the decline of sleep quality are all risk factors for hopelessness^{[10, 11]}.

To clarify the causes of hopelessness among caregivers of patients with cancers, we investigated the current situation of hopelessness and fatigue, rumination thinking, and sleep quality of family caregivers by issuing questionnaires. We subsequently studied the relationship between these factors, and explored the internal action path between them. This study aimed to provide a theoretical basis to prevent and reduce hopelessness among family caregivers of patients with cancers, maintaining their physical and mental health, and improving their quality of life.

2.1. Ethical considerations

All participants in this study signed informed consent forms and were assured that their privacy would not be compromised. We guarantee that the completed questionnaires were not lost, and that the original questionnaires were properly stored in the database after entering the data. This article does not contain any content that may disclose participants’ information.

Participants were informed of the purpose and methods of the study, the risks and benefits of participation, the confidentiality of their data, and the voluntary nature of participation. Written informed consent was obtained prior to conducting interviews for item development and refinement. The return of the completed anonymous questionnaire was taken as indicative of consent to participate in the main study. The study protocol was approved by the ethics committee of the First Affiliated Hospital of Jinzhou Medical University (KYLL202127). This study was conducted under the supervision of an ethics committee, and all methods were performed in accordance with the Declaration of Helsinki.

2.2. Study design and participants

Using the convenient sampling method, family caregivers of cancer patients were selected from the Department of Oncology of three first-class hospitals in Liaoning Province from May 2021 to May 2022. The inclusion criteria were as follows:① age ≥ 18 years old; ② Served as the main caregiver of patients pathologically diagnosed with a cancer; ③ Responsible for taking care of the patient's daily life, participating in the diagnosis and treatment activities when the patient is hospitalized, with a care time ≥ 1 month; ④ caregivers had to have a certain level of expression and reading ability, and were able to fill in the questionnaire; ⑤ signed the informed consent form for this study. The exclusion criteria were: ① caregivers experienced a major negative life events in recent years; ② nannies or nursing workers employed for salary; ③ history of mental illness; ④ the caregiver has cancer, cardiovascular and cerebrovascular disease, or other major diseases;

2.3 Sample size calculation

The number of participants included in the study was roughly estimated as 10 times the highest items of the scale. The scale with the most items in this study had 22 items and the general data questionnaire included eight items. Considering that 15% of the questionnaires would be invalid, we estimated that at least 353 caregivers needed to be investigated. In total, 537 participants were included in this study.

2.4. Measurements

2.4.1 General demographic characteristics questionnaire

A thorough literature review was conducted,We summarized the research instruments used in this relevant literature and selected some of these questionnaires for a pre-survey, after which the team designed the study questionnaire. The eight socio-demographic items investigated were age, gender, education level, marital status, occupation, family income, relationship with patients, and duration of illness (from the date of diagnosis).

2.4.2 Beck Hopelessness Scale, BHS

The BHS was compiled by the American psychologist Aaron T. Beck in 1959, and is commonly used to evaluate subjects' negative emotions or suicidal ideas about future life. The scale includes three factors: feelings about the future (7 items), loss of motivation (8 items), and expectations for the future (5 items). The total score ranges from 0 to 20, and results are divided into four levels according to the total score: 0–3, normal; 4–8, mild hopelessness; 9–14, moderate hopelessness; and 15–20, severe hopelessness^[4]. The higher the score, the higher the sense of hopelessness. In this study, this scale had a Cronbach's α value of 0.85.

2.4.3 Nolen- Hoeksema Ruminative Responses Scale, RRS

The RRS was developed by Hoeksema in 1991^[12], and was originally used to evaluate the response styles of depressed individuals. The revised scale has 22 items, and each item is scored on a four-point Likert scale. The higher the score, the higher the ruminant thinking level of an individual^[13]. This scale was translated into Chinese for the purpose of this study. After Sinicization, this ruminant thinking response scale included three dimensions and 22 items: symptomatic rumination, forced thinking, and reflective thinking. In this study, the total scale Cronbach's α value was 0.90, and the dimensions were 0.85, 0.72, and 0.68.

2.4. 4 Fatigue Scale-14, FS-14

This scale was compiled by Trudie Chalder of the Department of Psychological Medicine, Kings College Hospital, UK in 1992^[14]. This scale consists of 14 items, each of which are answered "yes" or "no", according to whether its content is consistent with the actual situation of the subjects. The scale consists of two dimensions: physical fatigue (8 items) and mental fatigue (6 items). The answer of "yes" or "no" to each question is recorded as "0" or "1", according to the positive and negative scores. The total score ranged from 0 to 14. The higher the score, the more serious the fatigue. In this study, the Cronbach’s alpha for the total scale was 0.86.

2.4.5 Pittsburgh sleep quality index, PSQI

The PSQI was originally compiled by Buysse DJ^[15], a sleep expert in the Sleep and Biological Rhythm Research Center of the Psychiatric Department of the University of Pittsburgh Medical Center in 1993, and was used to evaluate the subjective sleep quality of subjects in the last month. The reliability and validity of the scale were tested by Liu et al. in 1996^[16]. The scale is composed of 19 self-evaluations and five other evaluation items, of which 18 items form seven factors. Each factor was scored on a grade of 0–3. The total score is calculated as the cumulative score of each factor component, ranging from to 0–21. The higher the score, the worse the sleep quality. In this study, Cronbach’s α for the total scale was 0.71.

2.5 Data analysis

The original data were input into EpiData 3.1, SPSS 26.0, the measurement data were described as ± s, and the correlation between factors was analyzed using Pearson correlation. Path analysis was performed using AMOS 22.0. The inspection level was set at α = 0.05.

3.1. Baseline characteristics of family caregivers

A total of 536 caregivers were investigated, including 306 males (57.09%) and 230 females (42.91%); the age range was 24–69, with an average age of 50.30 ± 7.99 years. The time range of caring for patients was 1–5 years, with an average length of care of 3.01 ± 0.962 years; the relationship to patients were; 418 spouses (77.99%), 28 children (5.22%), 14 parents (2.61%), 32 brothers and sisters (5.97%), and 44 other relatives (8.21%). Table 1 shows the basic information of the research objects

Table 1

Basic information of study participants
Variables	Number	Rate
Gender
Male	306	57.09%
Female	230	42.91%
Occupation
Civil Servant	82	15.30%
Technician	228	42.54%
Businessman	134	25.00%
Farmer	28	5.22%
Unemployed	64	11.94%
Marital Status
In Marriage	501	93.47%
Single	5	0.93%
Divorce	22	4.10%
Widowed	8	1.49%
Educational Background
Primary School Education	35	6.53%
Junior High School Education	271	50.56%
High School / Technical Secondary School	125	23.32%
University/College Education	85	15.86%
Graduate Education Or Above	20	3.73%
Relationship With Patients
Children	28	5.22%
Parent	14	2.61%
Spouse	418	77.99%
Brothers And Sisters	44	8.21%
Other Relatives	32	5.97%
Monthly Income
< 5000	368	68.66%
5001–8000	125	23.32%
8001–10000	38	7.09%
> 10000	5	0.93%

3.2 Current situation of fatigue, rumination thinking, sleep quality and hopelessness of family caregivers

3.2.1 Fatigue status of patients with cancers

The total fatigue score of the 536 respondents was 10.20 ± 2.50, the score range was 3–14, the average score of physical fatigue dimension was 6.09 ± 0.97, and 455 (84.89%) participants answered “yes” to the question "do you feel your physical strength is not sufficient?". The average score of mental fatigue dimension was 4.11 ± 1.56. In the dimension of mental fatigue, 532 (99.25%) participants answered "yes" on the question "do you have difficulty concentrating". Overall, 504 caregivers (94.03%) had a total fatigue score of more than 7.

3.2.2 Ruminative thinking

The average total score for ruminative thinking was 43.42 ± 5.89, and the score range was 26–61 points. The average total score of the depression factor was 24.98 ± 3.66, and the score of numbness to other things was the highest, at 3.19 ± 0.54; the total score of the forced meditation factor was 9.73 ± 1.59, and the highest score was 2.88 ± 0.45. The total score of the reflection factor was 8.94 ± 1.51, among which the score of "I often think alone about why it is like this" was the highest (1.97 ± 0.27). A total of 73.69% of the caregivers (395 / 536) had a higher than average total score on ruminative thinking.

3.2.3 Sleep quality

The total sleep score was 8.35 ± 1.59, with a score range of 4–15. In total, 6.7% (36 / 536) of the caregivers had poor sleep quality; the average sleep time of 5.7% (31 / 536) of the caregivers was 19.66 ± 2.12 min, and 11.00% of the caregivers had difficulty falling asleep < 1 night/week. The total sleep quality score and each factor score are presented in Table 2.

Table 2

Fatigue, rumination, sleep status and hopelessness of caregivers of cancer patients
Variable	(x̄±s)	Score range	Variable	(x̄±s)	Score range
FS-14			PSQI
physical fatigue	6.09 ± 0.97	3–8	sleep quality	1.07 ± 0.25	0–2
mental fatigue	4.11 ± 1.56	0–6	sleep latency	1.06 ± 0.23	1–2
Total score	10.20 ± 2.50	3–14	sleep time	1.07 ± 0.28	0–3
RRS			sleep efficiency	1.08 ± 0.31	0–3
Depression	24.98 ± 3.66	15–33	sleep disturbance	1.05 ± 0.24	0–3
Forced meditation	9.73 ± 1.59	6–13	Sleeping drugs	1.98 ± 0.47	1–3
Reflection factor	8.94 ± 1.51	5–12	Daytime sleep disorders	1.05 ± 0.23	0–3
Total score	43.42 ± 5.89	26–61	Total score	8.35 ± 1.59	4–15
BHS
Feelings about the future	4.00 ± 1.61	0–7
Loss of motivation	5.18 ± 2.69	0–8
Expectations for the future	1.29 ± 1.42	0–5
Total score	10.47 ± 5.32	1–20

3.2.4 Hopelessness

The results of the Baker’s despair scale showed that 41.42% (222 / 536) of family caregivers had a total despair score above 10. The total despair and average scores for each dimension are presented in Table 2.

3.3 Correlation analysis of caregivers' fatigue, rumination thinking, sleep quality, and hopelessness in patients with cancers

Pearson correlation analysis showed a positive correlation between the total scores of the RRS, fs-14, PSQI, and BHS (r = 0.483–0.906, P < 0.01). The correlation analysis between fatigue, rumination thinking, sleep status, and hopelessness of family caregivers of cancer patients is shown in Table 3.

Table 3

Correlation Analysis of fatigue, rumination, sleep status and hopelessness of caregivers of cancer patients
	RRS	FS-14	PSQI	BHS
RRS	1
FS-14	0.906**	1
PSQI	0.619**	0.503**	1
BHS	0.903**	0.841**	0.483**	1
“”: P<0.05;“*”: P<0.01

3.4 Path analysis of caregivers' fatigue, rumination thinking, sleep quality, and hopelessness in patients with cancers

By consulting the relevant literature and data, we identified the following action pathways among caregivers' fatigue, rumination thinking, sleep quality and hopelessness of patients with cancers: ① Fatigue → rumination thinking; ② Sleep quality → rumination thinking; ③ Fatigue → Rumination thinking → Hopelessness ④ Sleep quality → Rumination thinking → Hopelessness ⑤ Hopelessness → Sleep quality. The structural equation model of caregivers' fatigue, ruminative thinking, sleep quality, and hopelessness in caregivers of patients with cancers is shown in Fig. 1, the results of each direct path effect are reported in Table 4, and the goodness-of-fit of the model is reported in Table 5.

Table 4

Direct path coefficients and significance test of fatigue, sleep quality, rumination and hopelessness of caregivers of patients with malignant tumor
Path	Estimated value	SE	Critical value	P
Fatigue→Sleep quality	0.941	0.197	4.783	0.000
Fatigue→Rumination thinking	0.865	0.049	17.492	0.000
Sleep quality→Rumination thinking	0.738	0.076	9.683	0.000
Rumination thinking→Hopelessness	0.870	0.020	44.070	0.000
Hopelessness→Sleep quality	-0.567	0.188	-3.023	0.018

Table 5

Model fitting index of fatigue, sleep quality, rumination and hopelessness of caregivers of patients with malignant tumor
Indexes	χ²/df	P	GFI	IFI	TLI	CFI	RMESEA
Fitting index	0.137	0.712	1.000	1.001	1.003	1.000	0.000
Evaluation criterion	≤ 3	>0.05	>0.90	>0.90	>0.90	>0.90	<0.10

4.1 Family caregivers have a high level of hopelessness

In this study, the Beck Hopelessness Scale score of caregivers of patients with cancer patients was 10.47 ± 5.32, which is consistent with the research results of previous studies^[4]. This score indicates that the hopelessness level of caregivers of cancer patients is high, and the scores of the F-14, RTS, and PSQI were all significantly higher than those of normal people in China^[14]. This indicates that family caregivers of patients with cancers have serious physical and mental health problems, which may be related to the physical and mental health of being caregivers. Caregivers of patients with cancers often ignore their own health problems, and other family members and medical staff of patients with cancers often only pay attention to the diagnosis and treatment of the patients themselves. It is a very common phenomenon in China that nurses ignore the physical and mental health of caregivers^[18], and there is little research on the physical and mental health of caregivers of patients with chronic diseases, resulting in a lack of relevant knowledge for maintaining the physical and mental health of such individuals. The long-term lack of sleep and excessive physical and mental load of caregivers will not only cause diseases, but can also lead to other serious consequences. Therefore, timely and effective interventions must be carried out to maintain the quality of life of caregivers to ensure their normal functioning.

4.2 Rumination thinking can lead to hopelessness

Our correlation test and model results revealed that rumination thinking can lead to hopelessness, which is a significant mental burden on a person when a relative is diagnosed with a cancer, and is regarded as a negative life event. The generation of negative life events can make caregivers more depressed, causing them to repeatedly think about the reasons for their plight, fall into sadness and depression, and aggravate rumination thinking. The trial of the Nolen Hoeksema Rumination Scale in China, published in the Chinese Journal of Clinical Psychology^[13], found that rumination thinking can directly lead to depression, and the theory of depression proposed by Abramson, Metalsky, and Alloy in 1989^[20] proposes that when negative events occur, in some people with cognitive susceptibility to depression ① attribute it to their own incompetence or defects, ② no effort can avoid disappointing results or achieve their expected effects, ③ attribute the occurrence of negative events to universal and lasting reasons. This leads directly to a sense of hopelessness.

4.3 Fatigue lead to sleep quality and rumination thinking

We found that fatigue affected sleep quality and rumination thinking. The research object of this survey was the caregivers of patients with cancers. Caregivers need to help patients complete various examinations in the hospital and cooperate with doctors and nurses to treat them. At home, they need to take care of the patient’s daily life, and observe the situation of patients at all times. In our study, 88.09% of caregivers had jobs, including as civil servants, employees of enterprises and institutions, and as self-employed persons. In addition to facing heavy work, they need to deal with their relationships with leaders, colleagues, customers, and other social relationships. When they return home, they need to assume the roles of parents, children, and spouses, and bear the corresponding responsibilities and obligations. Long term overload causes them to lose their physical and mental strength, resulting in them feeling exhausted. It has been well documented that prolonged high physical workload can cause insomnia^{[15, 16]}, and certainly our study results confirm this. However, we did not find direct evidence that high physical workload leads to rumination thinking. However, previous studies have confirmed that prolonged high workloads can directly lead to mental illness such as anxiety and depression, and rumination thinking is the most predominant symptom in depressed patients^[17].

4.4 Sleep quality can lead to rumination thinking

This survey found that all caregivers used sleeping drugs, and 99.99% of caregivers had less than 7h of effective sleep time. Sleep is an important physiological process. A regulatory mechanism for nerve cells in the cerebral cortex is to protect nerve cells and excite them to provoke normal physiological activities after continuous excitation. Some basic studies have shown that ruminative thinking is related to the excessive inhibition of thinking produced by the medial temporal lobe in two brain regions of the midline: the medial prefrontal lobe and the posterior cingulate gyrus^[19]. Lack of sleep aggravates this inhibition^[20]. A large number of empirical studies have shown that lack of sleep reduces attention and memory^[21], emotional instability^[22], and lack of patience^[23], which can directly lead to mistakes or conflicts with others in the process of daily life, work, and taking care of patients, resulting in negative life events. This vicious circle will make people feel like they have "bad luck", and can worsen rumination.

4.5 Hopelessness can affect sleep quality

Hopelessness can lead to a decline in sleep quality. The sense of hopelessness is composed of a sense of inferiority, decreased ability, and gloomy. It is a serious negative emotion, and studies have confirmed that long-term exposure to a certain negative emotions can lead to autonomic nerve dysfunction and sleep disorders characterised by rapid eye movement sleep behavior disorder^[24].

4.6 Clinical implications

This study has several clinical implications. The results of this study show that the physical and mental health status of family caregivers of cancer patients is worrying. Family caregivers often focus on caring for patients without realizing the importance of their own health. However, we must realize that if caregivers are unhealthy, they cannot bear the burden of caring for patients, nor can they effectively play other social roles. If the caregivers become sick, their family medical expenditure will increase. Hence, we should emphasize in health propaganda that caregivers should pay attention to their physical and mental health. People who take care of patients with cancers for a long time can often reduce their mental fatigue, eliminate tension, depression, and other negative emotions by listening to classical music and engaging in mindfulness meditation to allow relaxation for a period of time when necessary^[25]. In terms of improving sleep, caregivers should try to get enough sleep, adhere to a regular, healthy sleep schedule,and avoid strenuous exercise before sleep. They should also try to eat foods that help sleep, such as warm milk, bananas, oats, and almonds, but avoid forced sleep and drug abuse. If necessary, a psychiatrist should be consulted for professional help^[26].

There are multiple action paths among caregivers' fatigue, sleep quality, rumination thinking, and hopelessness which can help us to effectively identify and predict caregivers' hopelessness and further implement targeted measures to maintain their physical and mental health. Nurses can make assessments when communicating with family caregivers. If the caregiver is found to have insufficient sleep and complains that they often feel tired and cannot be effectively relieved, the nurse can suggest that they engage in jogging, yoga, Tai Chi^[27], meditation, or progressive muscle relaxation exercises to relax their muscles and minimize the use of hypnotic drugs, as well as introduce them to some food or vitamins that help sleep. In this study, we found that in caregivers who have developed a sense of despair, adequate and high-quality sleep is an effective method to prevent further aggravation of despair. Hence, caregivers with excessive mental tension and ruminating thinking should advise them to seek the help of psychologists or psychiatrists.

4.7 Limitations

Since the sampling method of this study is convenience sampling method selection bias may have been caused by convenience sampling and voluntary participation. This study aimed to provide a theoretical basis to prevent and reduce hopelessness among family caregivers of patients with cancers. Therefore the study cannot be a treatment for people who have become desperate.

Research on the physical and mental health of caregivers of patients with chronic diseases is still rare in China, and the physical and mental health of caregivers has not yet received sufficient attention. The physical and mental health of family caregivers of patients with advanced cancers should not be ignored in the context of advocating for universal health. Screening for physical and mental disorders should be encouraged to assess whether such individuals require counselling and treatment. According to the related predictive factors, medical providers should pay more attention to emotional change, somatic function, and sleep quality to reduce levels of negative emotions and physical fatigue among family caregivers, not only to effectively prevent them from feeling desperate, but also to maintain their physical and mental health, and quality of life, and to help them improve their ability to deal with death.

Acknowledgments

The authors are grateful to the family caregivers who participated in this study and to the hospital managers for their strong support in collecting samples.

We would like to thank Editage (www.editage.cn) for English language editing.

Author contributions

Z. C. was responsible for analysing and interpreting the data and drafting the manuscript.

Y. C. Provide technical suggestions for scale and data collection.

H. Z was the principal investigator for this project and made critical revisions to the article and supervised the technical suggestions.

All the authors approved the final manuscript.

Data availability statement

The data that support the findings of this study are available from the corresponding author upon request; please contact the corresponding author via email.

Additional information

No funding was obtained for this study.

Ethical approval

Participants were informed of the purpose and methods of the study, the risks and benefits of participation, the confidentiality of their data, and the voluntary nature of participation. Written informed consent was obtained before the interviews for item development and refinement. The return of the completed anonymous questionnaire was taken as consent to participate in the main study. The study protocol was approved by the Ethics Committee of the First Affiliated Hospital of Jinzhou Medical University (NO.KYLL202127).

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No competing interests reported.