Association between Insomnia Symptoms and Risk of Heart Failure: A Meta-analysis of Prospective Cohort Studies

Background Insomnia, as one of the most prevalent sleep disorders, is frequently linked to Heart failure (HF). However, the precise relationship and potential risk of HF events associated with insomnia and subtypes of symptoms necessitate further investigation. Objective This updated meta-analysis aimed to evaluate the associations between HF and various insomnia symptoms, including difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), early-morning awakening (EMA) and non-restorative sleep (NRS). Methods A comprehensive literature search was conducted in PubMed, Web of Science, Embase, and the Cochrane Library to identify prospective cohort studies from inception to October 2023. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated to assess the correlation between insomnia and the risk of HF. Funnel plots and Egger’s tests were employed to assess publication bias. Results A total of 177,008 patients from seven eligible prospective cohort studies were included. The pooled minimally adjusted HR for HF was 1.26 (95% CI:1.09-1.45; P =0.001), indicating that insomnia was associated with increased risk of HF. Among the individual insomnia symptoms, only DIS showed a positive association with risk of HF (HR:1.14, 95% CI:1.04-1.25; P =0.005). DMS and NRS had no significant effect on the risk of HF ( P >0.05). In the subgroup analysis including age, sex and BMI, there were no significant differences between each group. Conclusion This meta-analysis confirms the link between insomnia and an increased risk of HF, particularly highlighting the importance of DIS as a potential predictor for HF. Clinical Perspective What is new? Insomnia is ubiquitous and seriously affects people’s normal work, life, and health. At present, prospective cohort studies have suggested that insomnia can increase the risk of heart failure (HF). However, in our meta-analysis, we firstly found that only Difficulty Initiating Sleep (DIS) was directly associated with an increased HF incidence, rather than other insomnia subtypes. This is a very interesting which suggests that DIS has a greater impact on the incident of HF. In addition, this points us that in the subsequent treatment of insomnia, maybe we should pay more attention to the treatment of DIS. What are the clinical implications? As insomnia symptoms can be assessed and identified early and are relatively manageable, the study of the relationship between insomnia and HF has potential important clinical significance. If further research confirms that the improvement of insomnia symptoms, especially DIS symptoms, contributes to the prevention of HF or the prognosis of HF patients, it will provide another new “track” for the prevention and treatment of HF. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial The systematic review was previously registered in PROSPERO (International Prospective Register of Systematic Reviews; Study Unique Identifier: 359352) ### Funding Statement Dr Ren is supported by the National High Level Hospital Clinical Research Funding (NO.2022-NHLHCRF-LX-02-0102?NO.2022-NHLHCRF-YXHZ-01?NO.2023-NHLHCRF-YYPPLC-ZR-05), Beijing Nova Program (NO.20220484171) and Beijing Demonstration Research Ward (NO.2022-YJXBF-03-03), Dr Gao is supported by the National Natural Science Foundation of China (82300439). ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Ethics approval and consent to participate Not applicable. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data in the manuscript is available * CI : confidence interval DIS : difficulty initiating sleeping DMS : difficulty maintaining sleeping EMA : early-morning awakening HF : heart failure HR : hazard ratio MeSH : medical subject heading NOS : Newcastle-Ottawa Scale NRS : non-restorative sleep PRISMA : Preferred Reporting Items for Systematic Reviews and Meta-analyses