Association of Sleep Duration With Atrial Fibrillation and Heart Failure: A Mendelian Randomization Analysis

Non-traditional risk factors for atrial fibrillation: epidemiology, mechanisms, and strategies

Atrial fibrillation (AF) has become the pre-dominant arrhythmia worldwide and is associated with high morbidity and mortality. Its pathogenesis is intricately linked to the deleterious impact of cardiovascular risk factors, emphasizing the pivotal imperative for early detection and mitigation strategies targeting these factors for the prevention of primary AF. While traditional risk factors are well recognized, an increasing number of novel risk factors have been identified in recent decades. This review explores the emerging non-traditional risk factors for the primary prevention of AF, including unhealthy lifestyle factors in current society (sleep, night shift work, and diet), biomarkers (gut microbiota, hyperuricaemia, and homocysteine), adverse conditions or diseases (depression, epilepsy, clonal haematopoiesis of indeterminate potential, infections, and asthma), and environmental factors (acoustic pollution and other environmental factors). Unlike traditional risk factors, individuals have limited control over many of these non-traditional risk factors, posing challenges to conventional prevention strategies. The purpose of this review is to outline the current evidence on the associations of non-traditional risk factors with new-onset AF and the potential mechanisms related to these risk factors. Furthermore, this review aims to explore potential interventions targeting these risk factors at both the individual and societal levels to mitigate the growing burden of AF, suggesting guideline updates for primary AF prevention.

The link between sleep duration and stroke risk

In this review paper, we explore the complex relationship between sleep duration and stroke risk, outlining the association of both insufficient sleep and excessive sleep with an increased risk of cerebrovascular diseases. We explore a U-shaped relationship between sleep duration and cardiovascular outcomes, including stroke. Our review explores findings from cohort studies, meta-analyses, and Mendelian randomization studies, highlighting the nuanced findings and identifying gaps in the current literature. We discussed the direct and indirect effects of sleep duration on stroke risk, considering factors such as atherosclerosis, atrial fibrillation, hypertension, and hyperlipidemia. We also discuss the methodological challenges inherent in current studies, such as the reliance on self-reported sleep measures and the need for more objective and comprehensive assessments. The paper emphasizes the importance of recognizing individual variations in optimal sleep duration and the potential confounding effects of sleep quality and other sleep-related disorders on stroke risk. Furthermore, we explore the potential mechanisms by which sleep duration may influence endothelial function, oxidative stress, and vascular compliance, suggesting areas for future investigation. The paper makes a compelling case for the inclusion of sleep duration as a key factor in stroke prevention strategies, recommending that healthcare professionals proactively assess and manage sleep patterns to mitigate stroke risk.

Sleep Deficiency and Cardiometabolic Disease

Epidemiologic studies have demonstrated that short sleep duration is associated with an increased risk of cardio-metabolic health outcomes including cardiovascular disease mortality, coronary heart disease, type 2 diabetes mellitus, hypertension, and metabolic syndrome. Experimental sleep restriction studies have sought to explain these findings. This review describes the main evidence of these associations and possible mechanisms explaining them. Whether sleep extension reverses these now widely acknowledged adverse health effects and the feasibility of implementing such strategies on a public health level is discussed.

Associations of accelerometer-measured sleep duration with incident cardiovascular disease and cardiovascular mortality

STUDY OBJECTIVES

This study aimed to determine the associations between accelerometer-measured sleep durations and the risks of incident cardiovascular disease (CVD) and CVD-related mortality.

METHODS

A total of 92 261 participants (mean age: 62.4 ± 7.8 years, 56.4% female) were included in UK Biobank between 2013 and 2015. Average daily sleep durations were measured using wrist-worn accelerometers over a 7-day period. Sleep durations were categorized as <7 hours/day, 7-9 hours/day (reference), and >9 hours/day. The incidence of CVD and CVD-related mortality were ascertained by hospital records and death registries.

RESULTS

During a median follow-up period of 7.0 years, a total of 13 167 participants developed CVD, and 1079 participants died of CVD. Compared with a sleep duration 7-9 hours/day, an accelerometer-measured sleep duration <7 hours/day but not >9 hours/day was associated with higher risks of incident CVD (HR 1.06, 95% CI: 1.02 to 1.10), CVD-related mortality (HR 1.29, 95% CI: 1.14 to 1.47), coronary heart disease (HR 1.11, 95% CI: 1.03 to 1.19), myocardial infarction (HR 1.14, 95% CI: 1.03 to 1.27), heart failure (HR 1.20, 95% CI: 1.08 to 1.34), and atrial fibrillation (HR 1.15, 95% CI: 1.07 to 1.24). A curvilinear dose‒response pattern was observed between accelerometer-measured sleep durations and incident CVD (poverall < .001), with L-shaped associations found for incident CVD and CVD-related mortality.

CONCLUSIONS

An accelerometer-measured sleep duration of <7 hours/day but not >9 hours/day was associated with elevated risks of incident CVD and CVD-related mortality. Maintaining adequate sleep may help promote cardiovascular health.

Cardiovascular Implications of Sleep Disorders Beyond Sleep Apnea

Purpose of Review

Sleep is crucial for human health and life. There is still limited attention to the association between sleep disorders beyond sleep apnea and cardiovascular (CV) health. We investigated the current evidence between non-respiratory sleep disorders and CV health.

Recent Findings

Current evidence suggests an important association between sleep duration, circadian rhythm, insomnia, disorders of hypersomnolence and CV health. Sleep-related movement disorders exhibit a moderate association with CV health. Further research is needed to explore the effects of each sleep disorder on CV health.

Summary

Given the close association between non-respiratory sleep disorders and CV health, it is crucial to recognize and address sleep disorders in patients with a high CV risk.

Analyzing the impact of sleep duration on atrial fibrillation risk: a comprehensive systematic review and meta-analysis

BACKGROUND

Recent studies have suggested an association between sleep duration and cardiovascular diseases; however, the link to AF is inconclusive. This study aimed to explore the relationship between sleep duration and AF by conducting a systematic review and meta-analysis of primary studies to provide evidence of the link between insufficient sleep and AF.

METHODS

A review of the existing literature was conducted to identify the primary studies that examined the association between AF and sleep duration. The inquiry spanned databases, including PubMed, Embase, MEDLINE, and Google Scholar, from their inception through October 2023.

RESULTS

Meta-analysis revealed a statistically significant association (p < 0.01) between shorter sleep duration and the incidence of AF (hazard ratio (HR), 1.18; 95% CI, 1.03-1.34; I2 = 89%). Conversely, longer sleep duration did not exhibit a statistically significant association with the incidence of AF (HR, 1.03; 95% CI, 0.92-1.14; I2 = 66%, p = 0.02). The sensitivity analysis demonstrated reduced heterogeneity after excluding specific studies.

CONCLUSION

Insufficient sleep duration was associated with an increased risk of AF, whereas a longer sleep duration did not show a significant correlation. Standardized methods for sleep assessment and AF diagnosis as well as adjustments for confounding factors are suggested for future studies to improve the clarity and understanding of these associations.

Association Between Sleep Duration and Atrial Fibrillation: A Narrative Review

Sleep duration is a substantial risk factor for several cardiovascular diseases, including atrial fibrillation (AF). Despite much research, the precise nature of the relationship between the amount of sleep and AF remains unclear. This narrative review explores the relationship between AF and sleep duration, looking at genetic, mechanistic, and epidemiological data to explain this association. A U-shaped association (nonlinear relationship or curvilinear association) between sleep duration and AF has been seen, where longer and shorter sleep duration, more or less than seven to eight hours, have been associated with increased AF risk. Multiple mechanisms such as autonomic dysfunction, inflammation, and structural atrial remodeling have been proposed linking sleep disturbances to AF. Moreover, confounding factors such as individual lifestyle, comorbidities, and sleep quality could affect this association. Additionally, the interpretation of study results is further impacted by methodological limitations, including self-reported sleep duration and observational study designs. It is imperative to comprehend the complex relationship between sleep duration and AF to develop effective preventive and therapeutic methods. The main goals of future research should focus on prospective cohort studies with objective sleep metrics, exploring the mechanistic pathways, and comprehensive confounder adjustments that link sleep disturbances to AF. In summary, addressing sleep disturbances may represent one of the novel approaches to AF prevention and management, with potential implications for improving cardiovascular health and reducing AF-related morbidity and mortality.

Increased susceptibility to new-onset atrial fibrillation in diabetic women with poor sleep behaviour traits: findings from the prospective cohort study in the UK Biobank

BACKGROUND

Diabetic individuals often encounter various sleep-related challenges. Although the association between sleep duration and atrial fibrillation (AF) have been explored, the association of other sleep traits with the incidence of AF remains unclear. A comprehensive understanding of these traits is essential for a more accurate assessment of sleep conditions in patients with diabetes and the development of novel AF prevention strategies.

METHODS

This study involved 23,785 patients with diabetes without any pre-existing cardiovascular disease, drawn from the UK Biobank. Sleep behaviour traits examined encompassed sleep duration, chronotype, insomnia, snoring and daytime sleepiness. Sleep duration was categorised into three groups: low (≤ 5 h), proper (6-8 h) and long (≥ 9 h). We assessed associations using multivariate Cox proportional risk regression models. Furthermore, four poor sleep behaviours were constructed to evaluate their impact on the risk of new-onset AF.

RESULTS

Over a mean follow-up period of 166 months, 2221 (9.3%) new cases of AF were identified. Short (hazard ratio (HR), 1.28; 95% confidence interval (CI) 1.10-1.50) and long sleep durations (HR 1.16; 95% CI 1.03-1.32) consistently exhibited an elevated risk of AF compared to optimal sleep duration. Early chronotype, infrequent insomnia and daytime sleepiness were associated with 11% (HR 0.89; 95% CI 0.82-0.97), 15% (HR 0.85; 95% CI 0.77-0.95) and 12% (HR 0.88; 95% CI 0.81-0.96) reduced risk of new-onset AF, respectively. However, no significant association was found between snoring and the incidence of AF (HR 0.99; 95% CI 0.91-1.07).

CONCLUSIONS

In diabetic populations, sleep duration, chronotype, insomnia and daytime sleepiness are strongly associated with AF incidence. An optimal sleep duration of 6-8 h presents the lowest AF risk compared to short or long sleep duration. Additionally, poor sleep patterns present a greater risk of new-onset AF in women than in men.

Sleep Deficiency and Cardiometabolic Disease

Epidemiologic studies have demonstrated that short sleep duration is associated with an increased risk of cardio-metabolic health outcomes including cardiovascular disease mortality, coronary heart disease, type 2 diabetes mellitus, hypertension, and metabolic syndrome. Experimental sleep restriction studies have sought to explain these findings. This review describes the main evidence of these associations and possible mechanisms explaining them. Whether sleep extension reverses these now widely acknowledged adverse health effects and the feasibility of implementing such strategies on a public health level is discussed.

Self-reported daytime napping, daytime sleepiness, and other sleep phenotypes in the development of cardiometabolic diseases: a Mendelian randomization study

AIMS

Sleep disorders are associated with an increased risk of cardiometabolic diseases in observational studies, but the causality remains unclear. In this study, we leveraged two-sample Mendelian randomization (MR) analyses to assess the causal associations of self-reported daytime napping, daytime sleepiness, and other sleep phenotypes with cardiometabolic diseases including ischaemic stroke (IS), coronary artery disease (CAD), heart failure (HF), and Type 2 diabetes mellitus (T2DM).

METHODS AND RESULTS

We selected genetic variants as instrumental variables for self-reported daytime napping, daytime sleepiness, morning person, insomnia, short sleep duration, and long sleep duration from European-descent genome-wide association studies (GWASs). Summary statistics for cardiometabolic diseases originated from four different GWASs with a total of 2 500 086 participants. We used the inverse-variance weighted method to explore the role of self-reported sleep phenotypes on the aetiology of cardiometabolic diseases in the main analyses, followed by several sensitivity analyses for robustness validation. Genetically predicted self-reported daytime napping [T2DM: OR, 1.56 (95% confidence interval, 1.21-2.02)], insomnia [IS: OR, 1.07 (1.04-1.11)]; CAD: OR, 1.13 (1.08-1.17); HF: OR, 1.10 (1.07-1.14); T2DM: OR, 1.16 (1.11-1.22); and short sleep duration [CAD: OR, 1.37 (1.21-1.55)] were causally associated with an elevated risk of cardiometabolic diseases. Moreover, genetically determined self-reported daytime sleepiness [CAD: OR, 2.05 (1.18-3.57); HF: OR, 1.82 (1.15-2.87)] and morning person [HF: 1.06 OR, (1.01-1.11)] had potential detrimental effect on cardiometabolic risks.

CONCLUSION

Self-reported daytime napping, insomnia, and short sleep duration had causal roles in the development of cardiometabolic diseases, while self-reported daytime sleepiness and morning person was the potential risk factor for cardiometabolic diseases.

Associations between sleep duration and cardiovascular diseases: A meta-review and meta-analysis of observational and Mendelian randomization studies

The associations between sleep duration and cardiovascular diseases (CVDs) have been explored in many observational studies. However, the causality of sleep duration and many CVDs, such as coronary artery disease (CAD), heart failure (HF), and stroke, remains unclear. In this study, we conducted a systematic meta-review and meta-analysis of the results of observational and Mendelian randomization (MR) studies to examine how sleep duration impacts the risk of CVDs. We searched articles published in English and before 10 September 2021 in PubMed, Web of Science, and Embase. The articles were screened independently by two reviewers to minimize potential bias. We combined the meta-analyses of observational studies and 11 MR studies and summarized evidence of the effect of sleep duration on the risk of CAD, HF, stroke, and cardiovascular and all-cause mortality. Results showed that (a) evidence is accumulating that short sleep duration is a causal risk factor for CAD and HF; (b) abundant evidence from observational studies supports that long sleep duration is associated with the risk of CAD, stroke, and mortality, and long sleep duration has no causal associations with stroke and CAD in the MR studies; the causation of long sleep duration and other CVDs should be further studied; and (c) emerging evidence indicates that an increase in hours of sleep is associated with a decreased risk of CAD. Finally, we discussed the underlying pathophysiological mechanisms underlying short sleep duration and CVDs and suggested that increasing sleep duration benefits cardiovascular health.

Sleep Deficiency and Cardiometabolic Disease

Epidemiologic studies have demonstrated that short sleep duration is associated with an increased risk of cardio-metabolic health outcomes including cardiovascular disease mortality, coronary heart disease, type 2 diabetes mellitus, hypertension, and metabolic syndrome. Experimental sleep restriction studies have sought to explain these findings. This review describes the main evidence of these associations and possible mechanisms explaining them. Whether sleep extension reverses these now widely acknowledged adverse health effects and the feasibility of implementing such strategies on a public health level is discussed.

Association of Sleep Duration, Midday Napping with Atrial Fibrillation in Patients with Hypertension

Objective

This study aimed to assess the associations of sleep duration, midday napping and the risk of atrial fibrillation (AF) in patients with hypertension.

Methods

We conducted a cross-sectional study enrolling 11,524 hypertensive participates from the Chinese Hypertension Registry Study. Information on sleep duration and midday napping were obtained by a self-administered questionnaire. Multivariate logistic regression analyses were performed to estimate odds ratio (OR) and 95% confidence intervals (CIs) for the risk of AF.

Results

Compared with sleeping 6 to ≤8 hours/night, those reporting shorter sleep duration (≤5 hours/night) had a greater risk of AF (OR 1.95; 95% CI 1.28–2.95) in the fully adjusted model, while longer sleep (≥9 hours/night) was not significantly associated with the risk of AF. Compared with nonhabitual nappers, nappers had a higher risk of AF (OR 1.28; 95% CI 1.03–1.60) in the fully adjusted model. Moreover, we observed significant joint effects of sleeping ≤5 hours/night and nap (OR 2.13; 95% CI 1.09–4.14) on the risk of AF after adjusting for confounding factors.

Conclusion

Short sleep duration and midday napping were independently and jointly associated with higher risks of AF in patients with hypertension.

Sleep duration and atrial fibrillation risk in the context of predictive, preventive, and personalized medicine: the Suita Study and meta-analysis of prospective cohort studies

Background

Short and long sleep durations are common behaviors that could predict several cardiovascular diseases. However, the association between sleep duration and atrial fibrillation (AF) risk is not well-established. AF is preventable, and risk prevention approaches could reduce its occurrence. Investigating whether sleep duration could predict AF incidence for possible preventive interventions and determining the impact of various lifestyle and clinical characteristics on this association to personalize such interventions are essential. Herein, we investigated the association between sleep duration and AF risk using a prospective cohort study and a meta-analysis of epidemiological evidence.

Methods

Data of 6898 people, aged 30-84 years, from the Suita Study, were analyzed. AF was diagnosed during the follow-up by ECG, medical records, checkups, and death certificates, while a baseline questionnaire was used to assess sleep duration. The Cox regression was used to compute the hazard ratios (HRs) and 95% confidence intervals (CIs) of AF risk for daily sleep ≤ 6 (short sleep), ≥ 8 (long sleep), and irregular sleep, including night-shift work compared with 7 h (moderate sleep). Then, we combined our results with those from other eligible prospective cohort studies in two meta-analyses for the short and long sleep.

Results

In the Suita Study, within a median follow-up period of 14.5 years, short and irregular sleep, but not long sleep, were associated with the increased risk of AF in the age- and sex-adjusted models: HRs (95% CIs) = 1.36 (1.03, 1.80) and 1.62 (1.16, 2.26) and the multivariable-adjusted models: HRs (95% CIs) = 1.34 (1.01, 1.77) and 1.63 (1.16, 2.30), respectively. The significant associations between short and irregular sleep and AF risk remained consistent across different ages, sex, smoking, and drinking groups. However, they were attenuated among overweight and hypertensive participants. In the meta-analyses, short and long sleep durations were associated with AF risk: pooled HRs (95% CIs) = 1.21 (1.02, 1.42) and 1.18 (1.03, 1.35). No signs of significant heterogeneity across studies or publication bias were detected.

Conclusion

Short, long, and irregular sleep could be associated with increased AF risk. In the context of predictive, preventive, and personalized medicine, sleep duration should be considered in future AF risk scores to stratify the general population for potential personalized lifestyle modification interventions. Sleep management services should be considered for AF risk prevention, and these services should be individualized according to clinical characteristics and lifestyle factors.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-022-00275-4.