Prevalence and influencing factors of sleep disorders in patients with CRS: a protocol for systematic review and meta-analysis

Abstract

Background

Chronic rhinosinusitis (CRS) is a common chronic disease that seriously affects patients’ quality of life and imposes a heavy physical and mental burden on patients. There is growing evidence that sleep disorders are strongly associated with patients with CRS. However, there is no systematic evidence to clarify the prevalence and influencing factors of sleep disorders in patients with CRS with nasal polyps (NP) (CRSwNP) and CRS without NP (CRSsNP). For this reason, this study will systematically analyse the prevalence of sleep disorders in patients with CRSwNP and CRSsNP and explore the related influencing factors.

Methods and analysis

We will electronically search PubMed, Web of Science, Embase, Cochrane, Ovid, Scopus, the China National Knowledge Infrastructure, the Wanfang database, the China Biomedical Literature Database and the China Scientific Journals Database from the establishment of the database to September 2023 to collect the prevalence of sleep disorders in patients with CRSwNP or CRSsNP and related studies on factors affecting sleep disorders. Two researchers will independently conduct literature screening and data extraction and evaluate the quality of the included studies using the Newcastle-Ottawa Quality Scale and Agency for Healthcare Research and Quality scales. The extracted data will be meta-analysed using Review Manager 5.3 and Stata 14.0 software, and the quality of the evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation. Publication bias will be assessed using the funnel plots, Egger’s test and Begg’s test.

Ethics and dissemination

This review will not require ethical approval, as we will only use research data from the published documents. Our final findings will be published in a peer-reviewed, open-access journal for dissemination.

PROSPERO registration number

CRD42023446833.

Strengths and limitations of this study.

• This review will be conducted in accordance with recognised guidelines for reporting systematic reviews.

• Strict inclusion and exclusion criteria will be used to select studies eligible for this review.

• The Cochrane guidelines and the Grading of Recommendations Assessment, Development and Evaluation methodology will evaluate the risk of bias and the quality of the evidence for the included studies.

• The language restriction of Chinese and English is a limitation of this review.

Introduction

Chronic rhinosinusitis (CRS) is an inflammatory disease of the nasal mucosa and paranasal sinuses and is one of the most common diseases of the upper airways. It is characterised by more than 12 weeks of nasal congestion, runny nose, reduction or loss of smell and facial pain.^{1 2} Depending on the presence or absence of nasal polyps (NP), CRS can be further categorised as CRS with NP (CRSwNP) and CRS without NP (CRSsNP).² Clinical consensus diagnostic criteria based on a combination of symptomatic criteria and objective evidence suggest that the actual clinical prevalence of CRS is less than 5%, with nearly one-third of patients with CRSwNP.³ As a chronic disease, CRS seriously affects the quality of life of patients.⁴ Studies have shown that CRS disease results in at least 60 restricted workdays per patient per year as well as approximately $60 billion in socioeconomic expenditures annually, which places a heavy burden on patients, families and society.^{5 6} Patients with CRS often report the presence of poor physical and mental health, which is often thought to be caused by nasal conditions and is also associated with decreased productivity, absenteeism, poor concentration and memory loss, which directly or indirectly contribute to the development of sleep problems in patients.⁷

Sleep, as a part of health and disease, takes up a third of our daily lives, and sleep issues have been a constant source of concern.⁸ According to surveys, up to 70 million people suffer from sleep disorders each year, and the prevalence of sleep disorders in chronic diseases is generally higher than in the general population, and patients with CRS are no exception.^{9 10} Complaints about sleep problems can often be heard among patients with CRS. Surveys have shown that 60–75% of people with CRS have problems with sleep disruption.^11–14 These studies have also shown that the quality of sleep in people with CRS is even comparable to sleep-specific disorders.⁹ There is a significant association between CRS and sleep disruption. Sleep disruption, as a common concomitant manifestation in patients with CRS, seriously affects the quality of life, decreases the patient’s sense of well-being, may bring about undesirable complications such as cognitive impairment and depression and even affects the patient’s immune system.^{15 16} Therefore, it is crucial to pay close attention to the prevention, evaluation and management of sleep disruption in patients with CRS. Inflammation, the severity of the disease, such as nasal congestion and olfactory disturbances, the duration of the disease, tobacco use, age, gender and education are generally considered to be factors of interest as they are associated with sleep disorders in patients with CRS.^{11 17 18}

In recent years, there have been an increasing number of clinical studies on sleep disorders in patients with CRS, but there is a lack of systematic knowledge on their prevalence, especially the prevalence of different disease types and their respective influencing factors. Studies have found that nasal congestion due to NP is an independent risk factor for sleep disturbances in patients with CRS and that the severity of CRS disease has a serious negative impact on sleep function.¹² However, it has also been shown that NP does not worsen sleep problems in patients with CRS and the prevalence of sleep disturbances, and it has been found that patients with CRSwNP have a lower incidence of sleep disorders than patients with CRSsNP, despite displaying more severe nasal symptoms.^{13 19} In order to clarify the prevalence and influencing factors of sleep disorders in patients with CRSwNP and CRSsNP for more effective management, this study synthesised existing evidence, aiming to comprehensively understand the prevalence and influencing factors of sleep disorders in patients with CRSwNP and CRSsNP through systematic review and meta-analysis and provide the best evidence for research in this field.

Materials and methods

Study design

This systematic review and meta-analysis protocol will be conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P) guidelines²⁰ (see checklist in online supplemental additional file 1). The protocol has been registered with PROSPERO (CRD42023446833).

Eligibility criteria and exclusion criteria

Types of studies

Inclusion

We will include all major observational studies, including cohort, case-control or cross-sectional studies.

Exclusion

Reviews, commentaries and animal studies are excluded; literature for which full text is not available and duplicate data.

Types of participants

Inclusion

(1) Patients with a definitive clinical diagnosis of CRSwNP or CRSsNP based on the European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS2020)²; (2) report diagnostic criteria for sleep disorders in patients with CRSwNP or CRSsNP.

Exclusion

The article will be excluded if the study population includes patients with non-CRS patients who can not be separated.

Influencing factors

Age, gender, education, tobacco, duration of CRS, family income, treatment (medication, surgery), environmental factors, psychological factors, disease factors and inflammatory factors.

Types of outcomes measures

Report the prevalence of or factors influencing sleep disorders in patients with CRSwNP or CRSsNP.

Search strategy

Electronic searches will be performed on PubMed, Web of Science, Embase, Cochrane, Ovid, Scopus, the Chinese National Knowledge Infrastructure, the Wanfang Database, the Chinese Biomedical Literature Database and the Chinese Scientific Journal Database. The relevant literature on the prevalence and influencing factors of sleep disorders in patients with CRS will be collected from the establishment to September 2023. We will search using combinations of subject terms and free words, including combinations of rhinosinusitis, chronic rhinosinusitis, CRSwNP, CRSsNP, prevalence, sleep disorders, dyssomnias, sleep deprivation, poor quality sleep, Epworth score, sleep study, sleep apnoea, sleep hypopnoea, insomnia, sleepiness, somnolence, rapid eye movement (REM) sleep, non-REM sleep, epidemiology, incidence, influencing factor and risk factor*. The document search will be limited to relevant studies published in English and Chinese. In addition, we will also search the reference list of relevant studies and the grey literature to achieve the purpose of a comprehensive search. The search strategy is shown in online supplemental additional file 2.

Study selection

Retrieved records will be imported into EndNote X9 software for management and duplicates will be removed. Two reviewers will independently screen titles and abstracts to exclude irrelevant studies. Subsequently, the remaining literature will be then rigorously screened against the inclusion criteria to include eligible studies. Any disagreements will be resolved by discussion or consultation with a third researcher. The PRISMA flow diagram shows the retrieval and screening processes (figure 1).

Figure 1.

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis flow diagram.

Data extraction

Data will be extracted independently by two authors with strict reference to a pre-made datasheet, with the following extracts: study characteristics (authors, year of publication, study design, country and study setting (urban and rural)), demographic characteristics (disease type, sample size, age, sex, duration of disease, education and employment status), diagnostic criteria of sleep disorders and prevalence of sleep disorders and factors influencing them in patients with CRSwNP or CRSsNP. If any data is missing, contact the author to complete it. Disagreements should be resolved through discussion and negotiation with a third reviewer.

Risk of bias assessment

Two evaluators will assess the cross-sectional study using an 11-item instrument recommended by the Agency for Healthcare Research and Quality.²¹ Each item will be identified by a ‘yes’, ‘no’ and ‘unclear’, respectively. If the answer was ‘yes’, the score was ‘1’. If the answer was ‘no’ or ‘unclear’, the score was ‘0’. The quality of the included studies was ultimately categorised as ‘low’ (0–3 points), ‘moderate’ (4–7 points) or ‘high’ (8–11 points) quality.

The quality of research in cohort studies and case-control will be assessed using the NOS,²² which contains eight items divided into three modules (the selection of the study groups, intergroup comparability and exposure or outcome), with a maximum score of 1 for each of the items, except for the maximum score of 2 for intergroup comparability. The total score was 0–9, of which 0–4 are categorised as low-quality studies and 5–9 as high-quality studies.

Data synthesis

The RevMan 5.3 software and Stata 14.0 software will be used for data analysis. I² and Cochrane (Q) tests will be used to test the heterogeneity of the combined results. The I² values of 25%, 50% and 75% represented low, moderate and high heterogeneity among the studies, respectively.²³ When there is no significant heterogeneity among studies, pooled prevalence and 95% CI of sleep disorders in patients with CRS are analysed using a fixed-effects model; otherwise, a random fixed-effects model is used. The inverse variance method, or Mantel-Haenszel, is used to calculate the OR or mean difference of influencing factors for sleep disorders in patients with CRS. Funnel plots, Egger’s test and Begg’s test will be used to assess the publication bias of the included studies.

Subgroup analysis

If the data permit, we will conduct subgroup analyses to explore the prevalence of sleep disorders in patients with CRSwNP or CRSsNP by gender, age, country and setting (urban and rural).

Quality of evidence

The two authors will evaluate the quality of the evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE),²⁴ which will assess the following five domains: the risk of bias, inconsistency, indirectness, imprecision and publication bias. Evidence results will be categorised as ‘high’, ‘medium’, ‘low’ or ‘very low’.

Patient and public involvement

This study involves no patients or members of the public in its conception, execution or reporting.

Ethics and dissemination

This review will not require ethical approval, as we will only use research data from the published documents. Our final findings will be published in a peer-reviewed, open-access journal for dissemination.

Discussion

Available evidence suggests that patients with CRS exhibit poorer disease specificity and a poorer quality of life, which may be related to sleep dysfunction. A variety of factors, including inflammatory factors, disease factors, environmental factors, psychological factors, tobacco use and age, also affect sleep quality in patients with CRS with different disease types. Generally, sleep deprivation is associated with a range of adverse complications, resulting in memory impairment, cognitive impairment and anxiety and depression in patients. Considering the increase in the number of patients with sleep disorders in patients with CRS with different disease types, it is necessary to systematically analyse their prevalence and the factors affecting them. The aim of this study was to conduct a meta-analysis of the prevalence and influencing factors of sleep disorders in patients with CRSwNP and CRSsNP in order to provide more information on the current status and potential influencing factors of sleep disorders in patients with CRSwNP and CRSsNP. In order to prevent further aggravation of sleep disorders, medical personnel should pay timely attention to the health status of different types of patients with CRS and guide patients with CRSwNP and CRSsNP to reduce the influencing factors so as to reduce the incidence of sleep disorders in patients.

Ethics statements

Patient consent for publication

Not applicable.