The association of nighttime sleep duration and quality with chronic kidney disease in middle-aged and older Chinese: a cohort study

Insomnia and sleep duration for kidney function: Mendelian randomization study

OBJECTIVES

Extensive researches highlight the detrimental impact of sleep disorders such as insomnia and insufficient sleep duration on kidney function. However, establishing a clear causal relationship between insomnia, sleep duration, and kidney function remains challenging. This study aims to estimate this relationship using Mendelian randomization (MR).

METHODS

Independent genetic variants strongly associated with insomnia (N = 462,341) and sleep duration (N = 460,099) were selected as instrumental variables from corresponding genome-wide association studies (GWAS). Kidney function parameters, including serum creatinine, estimated glomerular filtration rate by cystatin C (eGFRcys), acute renal failure (ARF), chronic renal failure (CRF), kidney injury molecule-1, neutrophil gelatinase associated lipocalin, microalbuminuria, cystatin C, and β2 microglobulin, were derived from GWAS databases. A two-sample MR study was conducted to assess the causal relationship between sleep disorders and kidney function, and multivariable MR was used to identify potential mediators. The inverse-variance weighted was used as the primary estimate.

RESULTS

MR analysis found robust evidence indicating that insomnia and short sleep duration were associated with an increased risk of elevated serum creatinine, regardless of adjusting for obesity. Causal links between sleep duration and eGFRcys or cystatin C were also identified. While genetically predicted insomnia and sleep duration were found to potentially impact ARF, CRF, microalbuminuria, and β2 microglobulin, the p-values in multivariable MR analysis became nonsignificant. No pleiotropy was detected.

CONCLUSIONS

This study demonstrates a causal impact of insomnia on the risk of elevated serum creatinine and a positive effect of sleep duration on serum creatinine, eGFRcys, and cystatin C. Our findings also suggest their potential indirect effects on ARF, CRF, microalbuminuria, and β2 microglobulin mediated by obesity.

Sleep duration and risk of mortality from chronic kidney disease among Japanese adults

OBJECTIVE

To explore the association between sleep duration and death from chronic kidney disease in the general Japanese population.

METHODS

We conducted an 19.3-year follow-up study of 40,272 men and 54,902 women aged 40-79years and free of renal disease, cardiovascular disease and cancer in the Japan Collaborative Cohort Study for Evaluation of Cancer Risk at baseline (between 1986 and 1990). Sleep duration was categorized into five groups: <6, 6 to <7, 7 to <8, 8 to <9, and ≥9 hours per day. Cox proportional hazard models were used to analyze the association between sleep duration and death from chronic kidney disease.

RESULTS

Compared with persons with 7 to <8 hours sleep duration, those who slept 8 to <9 hours (HR: 1.41, 95% CI: 1.05-1.88) or ≥9hours (HR: 1.82, 95% CI: 1.28-2.58) per day had a higher risk of developing chronic kidney disease mortality. This association was particularly pronounced in individuals aged younger than 65years.

CONCLUSIONS

Sleep duration of 8 or more hours per day was associated with increased risk of chronic kidney disease mortality in the general Japanese population.

Association between nighttime sleep duration and quality with low back pain in middle-aged and older Chinese adults

BACKGROUND

This study aims to investigate the association between sleep duration, sleep quality, and the risk of low back pain (LBP) among middle-aged and elderly individuals in China.

METHODS

Utilizing data from the China Health and Retirement Longitudinal Study spanning 2011 to 2020, we categorized sleep duration into long, medium, and short categories, and sleep quality into good, fair, and poor levels. LBP status was determined based on self-reported information by participants. Multivariable logistic regression analysis was employed to assess the relationship between sleep duration, sleep quality, with the risk of LBP.

RESULTS

A total of 6750 individuals were included in the longitudinal study. After 9 years of follow-up, the prevalence of LBP was 25.69 %. In the fully adjusted model, compared to individuals with medium sleep duration, those with short sleep duration had a 28 % increased risk of developing LBP (OR = 1.28, 95%CI: 1.12, 1.46). Additionally, when compared to individuals with good sleep quality, those with fair and poor sleep quality had a 35 % (OR = 1.35, 95%CI: 1.19, 1.54) and 33 % (OR = 1.33, 95%CI: 1.12, 1.58) increased risk of LBP, respectively. Joint analysis of both factors revealed that individuals with poor sleep quality and short sleep duration had the highest risk of LBP.

CONCLUSION

Among middle-aged and elderly individuals in China, short sleep duration and poor sleep quality were associated with an increased risk of LBP. Future studies should further explore the mechanisms underlying this association and validate the findings through randomized controlled trials.

Joint effects of sleep disturbance and renal function impairment on incident new-onset severe metabolic dysfunction-associated steatotic liver disease

AIM

To elucidate the effects of sleep parameters and renal function on the risk of developing new-onset severe metabolic dysfunction-associated steatotic liver disease (MASLD).

MATERIALS AND METHODS

The primary analysis involved a cohort of 305 257 participants. Multivariable Cox models were employed to calculate hazard ratios and 95% confidence intervals. Traditional mediation and two-step Mendelian randomization (MR) analyses were conducted to assess the associations and mediating roles of renal function indicators between sleep and new-onset severe MASLD.

RESULTS

Poor sleep score and renal function biomarker score (RFS) were associated with an increased risk of new-onset severe MASLD (all ptrend <0.001). Participants with poor sleep patterns and the highest RFS had a 5.45-fold higher risk of new-onset severe MASLD, compared to those with healthy sleep patterns and the lowest RFS (p < 0.001). The RFS could explain 10.08% of the correlations between poor sleep score and risk of new-onset severe MASLD. Additionally, MR analyses supported a causal link between insomnia and new-onset severe MASLD and revealed a mediating role of chronic kidney disease in the connection between insomnia and new-onset severe MASLD risk.

CONCLUSIONS

This study highlights the independent and combined associations of sleep parameters and renal function indicators with new-onset severe MASLD, underscoring the bidirectional communication of the liver-kidney axis and providing modifiable strategies for preventing MASLD.

The association of sleep duration with the risk of chronic kidney disease: a systematic review and meta-analysis

Background and hypothesis

Published literature suggests that sleep duration and quality may be affected in adults with chronic kidney disease. However, the relationship between these two entities remains a matter of debate. The objective of this systematic review and meta-analysis is to assess the effect of sleep duration and quality on chronic kidney disease.

Methods

A systematic review of the Medline/PubMed, Embase, Cochrane Library, and CINAHL databases was conducted for articles pertaining to the association between sleep duration and quality on chronic kidney disease. The main outcome was the hazard/risk ratio of chronic kidney disease in patients of varying sleep durations and quality.

Results

In total, 42 studies (2 613 971 patients) with a mean age of 43.55 ± 14.01 years were included in the meta-analysis. Compared with a reference range of 7 to 8 hours of sleep, short sleep durations of ≤4 hours (RR 1.41, 95% CI: 1.16 to 1.71, P < 0.01), ≤5 hours (RR 1.46, 95% CI: 1.22 to 1.76, P < 0.01), ≤6 hours (RR 1.18, 95% CI: 1.09 to 1.29, P < 0.01), and ≤7 hours (RR 1.19, 95% CI: 1.12 to 1.28, P < 0.01) were significantly associated with an increased risk of incident chronic kidney disease. Long sleep durations of ≥8 hours (RR 1.15, 95% CI: 1.03 to 1.28, P < 0.01) and ≥9 hours (RR 1.46, 95% CI: 1.28 to 1.68, P < 0.01) were also significantly associated with an increased risk of incident chronic kidney disease. Meta-regression did not find any significant effect of age, gender, geographical region, and BMI and an association with sleep duration and risk of incident chronic kidney disease.

Conclusion

Both short and long sleep durations were significantly associated with a higher risk of chronic kidney disease. Interventions targeted toward achieving an optimal duration of sleep may reduce the risk of incident chronic kidney disease.

Short or long sleep duration was associated with chronic kidney disease in a Chinese nationwide cohort study

OBJECTIVE

Sleep duration is an important factor influencing health outcomes. The association between sleep duration and kidney function remains elusive. This study aimed to explore the association between sleep duration and chronic kidney disease (CKD) amongst Chinese adults.

METHODS

We conducted a cross-sectional study based on the China Health and Nutrition Survey (CHNS) in the wave of 2009. Participants were divided into three groups: ≤ 6 h/day (short sleepers), 7-8 h/day (regular sleepers) and ≥ 9 h/day (long sleepers) according to self-reported sleep duration. CKD was defined as estimated glomerular filtration rate < 60 mL/min/1.73 m2.

RESULTS

A total of 8096 Chinese adults (45.9% men) with a mean age of 50.6 years were included in the study. Compared with regular sleepers, both short and long regular sleepers had a higher prevalence of CKD. A U-shaped relationship between sleep duration and CKD was displayed by restricted cubic spline curve (P-overall < 0.001, P-nonlinear < 0.001). Multivariate logistic regression models revealed that both short and long sleep duration were clinically associated with higher odds of CKD, after adjustments for covariates [adjusted odds ratio (OR) 1.25 and 1.30; 95% confidence interval (CI) 1.00-1.56 and 1.08-1.54, for short and long sleep duration, respectively]. In subgroup analyses, we found the association was still observed in participants without hypertension or diabetes mellitus.

CONCLUSION

Short or long sleep duration was associated with CKD in the general population.

Associations of sleeping patterns and isotemporal substitution of other behavior with the prevalence of CKD in Chinese adults

Studies have found a U-shaped relationship between sleep duration and chronic kidney disease (CKD) risk, but limited research evaluated the association of reallocating excessive sleep to other behavior with CKD. We included 104 538 participants from the nationwide cohort of the Risk Evaluation of Cancers in Chinese Diabetic Individuals: A Longitudinal Study, with self-reported time of daily-life behavior. Using isotemporal substitution models, we found that substituting 1 h of sleeping with sitting, walking, or moderate-to-vigorous physical activity was associated with a lower CKD prevalence. Leisure-time physical activity displacement was associated with a greater prevalence reduction than occupational physical activity in working population. In stratified analysis, a lower CKD prevalence related to substitution toward physical activity was found in long sleepers. More pronounced correlations were observed in long sleepers with diabetes than in those with prediabetes, and they benefited from other behavior substitutions toward a more active way. The U-shaped association between sleep duration and CKD prevalence implied the potential effects of insufficient and excessive sleep on the kidneys, in which the pernicious link with oversleep could be reversed by time reallocation to physical activity. The divergence in the predicted effect on CKD following time reallocation to behavior of different domains and intensities and in subpopulations with diverse metabolic statuses underlined the importance of optimizing sleeping patterns and adjusting integral behavioral composition.

Association between nighttime sleep duration and quality with knee osteoarthritis in middle-aged and older Chinese: A longitudinal cohort study

BACKGROUND

The association between nighttime sleep duration and sleep quality with the risk of knee osteoarthritis (OA) remains unclear. This study aimed to examine the longitudinal association among middle-aged and older adults in China.

METHODS

The data used in this study were obtained from the China Health and Retirement Longitudinal Study (CHARLS) surveys conducted in 2011 and 2015. Nighttime sleep duration was categorized into five groups: <6 h, 6 to <7 h, 7 to <8 h, 8 to <9 h, and ≥9 h/night. Sleep quality was assessed by restless days in the past week (<1, 1-2, 3-4, and 5-7 days/week). Multivariate logistic regression models were used to assess the association between sleep duration and quality with incident knee OA.

RESULTS

A total of 11,114 participants who did not have knee OA at baseline were enrolled in this study. After 4 years of follow-up, the overall incidence of knee OA was 8.07 %. Compared to 7 to <8 h of sleep duration, short sleep duration (<6 h/night) was associated with a significantly increased risk of incident knee OA in the fully adjusted model [odds ratio (OR) =1.73, 95 % confidence interval (CI): 1.33-2.25]. Additionally, participants with 5-7 sleep restless days/week were associated with significantly increased risk of incident knee OA (OR = 1.88, 95 % CI: 1.48-2.38).

CONCLUSIONS

Short nighttime sleep duration and poor sleep quality are associated with increased risk of incident knee OA.

Spatial associations between chronic kidney disease and socio-economic factors in Thailand

Chronic kidney disease (CKD) is a persistent, progressive condition characterized by gradual decline of kidney functions leading to a range of health issues. This research used recent data from the Ministry of Public Health in Thailand and applied spatial regression and local indicators of spatial association (LISA) to examine the spatial associations with night-time light, Internet access and the local number of health personnel per population. Univariate Moran's I scatter plot for CKD in Thailand's provinces revealed a significant positive spatial autocorrelation with a value of 0.393. High-High (HH) CKD clusters were found to be predominantly located in the North, with Low-Low (LL) ones in the South. The LISA analysis identified one HH and one LL with regard to Internet access, 15 HH and five LL clusters related to night-time light and eight HH and five LL clusters associated with the number of health personnel in the area. Spatial regression unveiled significant and meaningful connections between various factors and CKD in Thailand. Night-time light displayed a positive association with CKD in both the spatial error model (SEM) and the spatial lag model (SLM), with coefficients of 3.356 and 2.999, respectively. Conversely, Internet access exhibited corresponding negative CKD associations with a SEM coefficient of - 0.035 and a SLM one of -0.039. Similarly, the health staff/population ratio also demonstrated negative associations with SEM and SLM, with coefficients of -0.033 and -0.068, respectively. SEM emerged as the most suitable spatial regression model with 54.8% according to R2. Also, the Akaike information criterion (AIC) test indicated a better performance for this model, resulting in 697.148 and 698.198 for SEM and SLM, respectively. These findings emphasize the complex interconnection between factors contributing to the prevalence of CKD in Thailand and suggest that socioeconomic and health service factors are significant contributing factors. Addressing this issue will necessitate concentrated efforts to enhance access to health services, especially in urban areas experiencing rapid economic growth.

Circadian syndrome is associated with the development of chronic kidney disease and rapid decline in kidney function in middle-aged and elder adults: a China nationwide cohort study

PURPOSE

The correlation between circadian syndrome (CircS) and kidney outcomes is currently supported by limited empirical evidence. Thus, the objective of this study was to determine the potential relationship between CircS and the development of chronic kidney disease (CKD), as well as the rapid decline in renal function.

MATERIALS AND METHODS

We utilized data from the 2011 China Health and Retirement Longitudinal Study (CHARLS), which involved 6002 Chinese adults ≥40 years of age. Among these participants, 3670 subsequently had follow-up evaluations in the 2015 survey. The primary outcome was the development of CKD, as defined by an estimated glomerular filtration rates decrease to a level <60 ml/min/1.73 m2, while the secondary outcome was rapid decline in renal function, as defined by an estimated glomerular filtration rates decrease of >5 ml/min/1.73 m2 per year. Multivariable logistic regression analysis was utilized to determine the association between CircS and kidney outcomes.

RESULTS

Compared to participants without CircS, those with CircS had a higher risk of CKD in the cross-sectional studies conducted in 2011 (OR, 1.292; 95% CI, 1.053-1.585) and 2015 (OR, 1.860; 95% CI, 1.469-2.355). Participants with CircS in the longitudinal cohort study had a higher risk of progressing to CKD (OR, 3.050; 95% CI, 2.052-4.534) and a rapid decline in renal function (OR, 1.959; 95% CI, 1.433-2.677) after 4 years of follow-up evaluations and adjustment for covariates. Moreover, participants who had CircS with ≥6 CirS components had the highest risk of a rapid decline in renal function (OR, 1.703; 95% CI, 1.054-2.753).

CONCLUSION

CirS significantly increased the risk of CKD progression and rapid decline in renal function among middle-aged and elder individuals. Our study findings highlights the importance of recognizing and managing CirC as a preventative strategy for CKD.

A machine learning driven monogram for predicting chronic kidney disease stages 3-5

Chronic kidney disease (CKD) remains one of the most prominent global causes of mortality worldwide, necessitating accurate prediction models for early detection and prevention. In recent years, machine learning (ML) techniques have exhibited promising outcomes across various medical applications. This study introduces a novel ML-driven monogram approach for early identification of individuals at risk for developing CKD stages 3-5. This retrospective study employed a comprehensive dataset comprised of clinical and laboratory variables from a large cohort of diagnosed CKD patients. Advanced ML algorithms, including feature selection and regression models, were applied to build a predictive model. Among 467 participants, 11.56% developed CKD stages 3-5 over a 9-year follow-up. Several factors, such as age, gender, medical history, and laboratory results, independently exhibited significant associations with CKD (p < 0.05) and were utilized to create a risk function. The Linear regression (LR)-based model achieved an impressive R-score (coefficient of determination) of 0.954079, while the support vector machine (SVM) achieved a slightly lower value. An LR-based monogram was developed to facilitate the process of risk identification and management. The ML-driven nomogram demonstrated superior performance when compared to traditional prediction models, showcasing its potential as a valuable clinical tool for the early detection and prevention of CKD. Further studies should focus on refining the model and validating its performance in diverse populations.

Depressive symptoms and sleep duration in relation to chronic kidney disease: Evidence from the China health and retirement longitudinal study

OBJECTIVE

Nowadays, the joint effects of depressive symptoms and sleep duration on the risk of chronic kidney disease (CKD) are still unclear. We aimed to prospectively assess the combined effect of depressive symptoms and sleep duration on the incidence of CKD in middle-aged and elderly Chinese population.

METHODS

A total of 10,953 participants from the China Health and Retirement Longitudinal Study (CHARLS) were included. Depressive symptoms were measured using the 10-item Center for Epidemiological Studies Depression scale (CESD-10). Sleep duration was evaluated by self-reported. CKD events were based on self-reported physicians' diagnosis or personal estimate glomerular filtration rate level (eGFR <60 mL/min/1.73 m2). Cox regression models were established to analyze the correlation between depressive symptoms, sleep duration and the risk of CKD.

RESULTS

Over a mean follow-up time was 6.76 ± 0.98 years, 851 (7.8%) participants had reported CKD events during the follow-up. Elevated depressive symptoms (HR = 1.65, 95% CI = 1.43-1.90) and short sleep duration (HR = 1.48, 95% CI = 1.27-1.72) were independently associated with an increased CKD risk after adjusting for potential confounding factors. Participants with short sleep duration (< 6 h)/elevated depressive symptoms (HR = 2.24, 95% CI = 1.89-2.65) were associated with the highest risk of CKD than those with normal sleep duration/low depressive symptoms.

CONCLUSIONS

Elevated depressive symptoms and short sleep duration were independent risk factors for CKD. There was a combined effect between depressive symptoms and sleep duration in increasing the risk of CKD.

Adverse childhood experiences and depressive symptoms among middle-aged or older adults in China and the mediating role of short sleep duration

BACKGROUND

Limited research has simultaneously examined the link between adverse childhood experiences (ACEs), short sleep duration, and depressive symptoms among middle-aged or older Chinese adults. This study aims to investigate the association between ACEs and later-life depressive symptoms, and to examine the mediating role of short sleep duration (<6 h/night) in this association.

METHODS

Data of 11,452 participants aged ≥45 years were obtained from the China Health and Retirement Longitudinal Study. Information on ACEs, depressive symptoms, and sleep duration were reported via questionnaires. The mediating effect of short sleep duration in the association between ACEs and depressive symptoms was examined by Baron and Kenny's causal steps method and Karlson/Holm/Breen (KHB) method.

RESULTS

Compared to non-exposed group, exposure to ACEs was significantly associated with increased odds of depressive symptoms in a dose-response pattern. The odds ratio of depressive symptoms increased from 1.27 (95 % CI: 1.11-1.46) for one ACE to 3.38 (95 % CI: 2.92-3.90) for ≥4 ACEs. The KHB method identified significant mediating role of short sleep duration in the association between experiencing three or more ACEs and depressive symptoms, with the proportional mediation estimated at 8.96 % and 8.85 % for the groups with 3 ACEs and ≥4 ACEs, respectively. The results were consistent across genders and gender did not moderate these associations.

LIMITATIONS

The cross-sectional design limited the ability to make causal inference.

CONCLUSIONS

ACEs were positively associated with depressive symptoms, and short sleep duration partially mediated this association. Promoting optimal sleep duration among ACE-exposed individuals might improve their mental health.

Effects of sleep duration and changes in body mass index on diabetic kidney disease: a prospective cohort study

Aims

To examine the associations of sleep duration and changes in BMI with the onset of diabetic kidney disease (DKD).

Materials and methods

2,959 participants with type 2 diabetes were divided into three groups based on sleep duration: short (<7 h/day), intermediate (7-9 h/day), or long (>9 h/day). Changes in BMI during follow-up were trisected into loss, stable, or gain groups. DKD was defined as either the urinary albumin/creatinine ratio (UACR) ≥ 3.39 mg/mmol or the estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73m², or both. Cox regression models were used to assess hazard ratios (HRs) and 95% confidence intervals (CIs).

Results

During a mean follow-up of 2.3 years, DKD occurred in 613 participants (20.7%). A J-shaped curve was observed between sleep duration and DKD. Compared to intermediate sleep duration, long sleep duration was associated with higher risks of DKD (HR 1.47; 95% CI: 1.19-1.81). In the joint analyses, compared to participants with intermediate sleep duration and stable BMI, long sleep duration with BMI gain had the highest risks of DKD (HR 2.04; 95% CI: 1.48-2.83). In contrast, short or intermediate sleep duration accompanied by decrease in BMI was associated with a reduced risk of DKD, with HRs of 0.50 (95% CI: 0.31-0.82) and 0.61 (95% CI:0.47-0.80), respectively.

Conclusions

Long sleep duration is significantly associated with an increased risk of DKD, which is further amplified by obesity or BMI gain. These findings suggest that both proper sleep duration and weight control are essential to preventing DKD.

Association between social jetlag and chronic kidney disease among the Korean working population

Social jetlag refers to the discrepancy between social time and the body's internal rhythm, which can lead to unfavorable health outcomes. However, no study has directly explored the relation between social jetlag and chronic kidney disease (CKD). This study aims to investigate the relationship between social jetlag and CKD in a representative population of South Korea. This study included 8259 currently economically active Korean population in the Korea National Health and Nutrition Examination Survey. Social jetlag was calculated as the difference between the midpoint of sleep time on weekdays and free days. The estimated glomerular filtration rate (eGFR) was calculated the by using the serum creatinine value according to the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Participants with an eGFR less than 60 ml/min/1.73 m² were defined as CKD cases. The estimated glomerular filtration rate decreased as social jetlag increased. Multiple logistic regression analysis showed that the adjusted odds ratio (95% confidence interval) of CKD for 1-2 h of social jetlag was 0.926 (0.660-1.299), while the odds ratio for more than 2 h was 2.042 (1.328-3.139) when less than 1 h was used as reference. This study found that social jetlag and risk of CKD were significantly related in the Korean working population.

Factors associated with poor sleep quality in patients with pre-dialysis chronic kidney disease: A systematic review

AIMS

To determine factors associated with poor sleep quality among patients with pre-dialysis chronic kidney disease.

DESIGN

This is a systematic review study guided by Preferred Reporting Items for Systematic Reviews and Meta-Analyses statements and checklist.

DATA SOURCES

Empirical evidence was sought in major electronic databases, including Embase, MEDLINE, CINAHL and Airiti library from March to September 2022.

REVIEW METHODS

Studies investigating factors associated with poor sleep quality among adult patients with chronic kidney disease were included. Study participants who received renal replacement therapy and had sleep disorders and serious illnesses such as cancer were excluded. Of the 526 studies that resulted from the search after removing duplicate articles, 20 studies were assessed for quality by using Joanna Briggs Institute and Newcastle-Ottawa Scale by two doctorial prepared nursing scientists.

RESULTS

A total of 20 studies were included in this review. The prevalence of poor sleep quality in these studies ranged from 11% to 97.5%. Demographics (older age and female), physiological conditions (higher body mass index, higher hip circumferences, higher systolic blood pressure, poor cardiovascular function, dyspnoea, pain, cramps, itchiness or moderate to extreme pruritus, lower fasting plasma glucose, electrolyte imbalance, higher total cholesterol and gastrointestinal symptoms), depression, smoking, arousal-related and cognitive arousal behaviours were associated with poor sleep quality.

CONCLUSION

Poor sleep quality was prevalent and influenced kidney function, increased mortality as well as decreased quality of life in patients with pre-dialysis chronic kidney disease. This review synthesizes factors associated with poor sleep quality. Managing these factors can mitigate and prevent poor sleep quality.

IMPACT

Healthcare providers, especially nurses, can assess the risk factors of poor sleep quality and reinforce patients' self-management. Future research should elucidate the assessment and management of risk factors and transfer these into widespread use in the routine care of patients with chronic kidney disease.

Sleep Quality and Cognitive Function after Stroke: The Mediating Roles of Depression and Anxiety Symptoms

This study examined the association between post-stroke cognitive function and sleep status at 30 days post-stroke and evaluated the role of anxiety and depression as potential mediators of that association. The participants in this study were 530 acute ischemic stroke (IS) patients. Sleep disturbance at 30 days post-stroke was assessed by the Pittsburgh Sleep Quality Index. Basic patient information, cognitive function, depression, and anxiety status were assessed before discharge from the hospital. Stratified linear regression analysis models were fit to examine the associations between post-stroke sleep quality and the influencing factors. A structural equation model was developed to evaluate the role of anxiety and depression as potential mediators of sleep quality and cognitive function. At 30 days post-stroke, 58.7% of IS patients had sleep disturbance. Women and older IS patients were more likely to suffer poorer sleep quality (p < 0.05). A stratified linear regression analysis showed that the inclusion of cognitive function variables and indicators of depression and anxiety were statistically significant in predicting improvement in the sleep disturbance of AIS patients. Cognitive function, depression, anxiety, and sleep status were selected to construct a structural equation model. The total effect of cognitive function on sleep status was -0.274, with a direct effect of -0.097 and an indirect effect (through depression) of -0.177. The total effect of anxiety on sleep status was 0.235, with a direct effect of 0.186 and an indirect effect (through depression) of 0.049. IS patients often experience poor sleep quality. Depression in IS patients mediates two pathways: the pathway through which cognitive function affects sleep quality and the pathway through which anxiety affects sleep quality.

Association between sleep duration and quality with rapid kidney function decline and development of chronic kidney diseases in adults with normal kidney function: The China health and retirement longitudinal study

Research have shown that sleep is associated with renal function. However, the potential effects of sleep duration or quality on kidney function in middle-aged and older Chinese adults with normal kidney function has rarely been studied. Our study aimed to investigate the association of sleep and kidney function in middle-aged and older Chinese adults. Four thousand and eighty six participants with an eGFR ≥60 ml/min/1.73 m² at baseline were enrolled between 2011 and 2015 from the China Health and Retirement Longitudinal Study. Survey questionnaire data were collected from conducted interviews in the 2011. The eGFR was estimated from serum creatinine and/or cystatin C using the Chronic Kidney Disease Epidemiology Collaboration equations (CKD-EPI). The primary outcome was defined as rapid kidney function decline. Secondary outcome was defined as rapid kidney function decline with clinical eGFR of <60 ml/min/1.73 m² at the exit visit. The associations between sleep duration, sleep quality and renal function decline or chronic kidney disease (CKD) were assessed based with logistic regression model. Our results showed that 244 (6.0%) participants developed rapid decline in kidney function, while 102 (2.5%) developed CKD. In addition, participants who had 3-7 days of poor sleep quality per week had higher risks of CKD development (OR 1.86, 95% CI 1.24-2.80). However, compared with those who had 6-8 h of night-time sleep, no significantly higher risks of rapid decline in kidney function was found among those who had <6 h or >8 h of night time sleep after adjustments for demographic, clinical, or psychosocial covariates. Furthermore, daytime nap did not present significant risk in both rapid eGFR decline or CKD development. In conclusion, sleep quality was significantly associated with the development of CKD in middle-aged and older Chinese adults with normal kidney function.

Linear and non-linear Mendelian randomization analyses of sex-specific associations between sleep duration and hyperuricemia

Background

Observational studies have suggested a potential non-linear association between sleep duration and hyperuricemia. However, the causal nature and sex-specific differences are poorly understood. We aimed to determine the shape of sex-specific causal associations between sleep duration and hyperuricemia in the UK Biobank.

Methods

Logistic regression was used to investigate the observational association between self-reported sleep duration and hyperuricemia among 387,980 white British participants (mean age: 56.9 years and 46.0% males). Linear and non-linear Mendelian Randomization (MR) analyses were performed to assess the causal association between continuous sleep duration and hyperuricemia. The causal effects of genetically predicted short (<7 h) and long (>8 h) sleep durations on hyperuricemia were further estimated, respectively.

Results

Traditional observational analysis suggested U- and J-shaped associations between sleep duration and hyperuricemia in females and males, respectively. Linear MR did not support the causal effect of sleep duration on hyperuricemia. Non-linear MR demonstrated an approximately U-shaped causal association between continuous sleep duration and hyperuricemia in overall participants and females, but not in males. Genetically predicted short sleep duration was significantly associated with hyperuricemia in females (OR [95% CI]: 1.21 [1.08–1.36]; P = 0.001), but not in males (1.08 [0.98–1.18]; P = 0.137). By contrast, genetically predicted long sleep duration was not significantly associated with the risk of hyperuricemia in either females or males.

Conclusion

Genetically predicted short sleep duration is a potential causal risk factor for hyperuricemia for females but has little effect on males. Long sleep duration does not appear to be causally associated with hyperuricemia.

Association between sleep and multimorbidity in Chinese elderly: Results from the Chinese Longitudinal Healthy Longevity Survey (CLHLS)

OBJECTIVE

Abnormal sleep duration and poor sleep quality were associated with multiple diseases. However, the association between sleep behavior (including sleep duration and quality) and multimorbidity among the elderly remains unclear. Thus, our study aimed to explore this association in the Chinese elderly.

METHODS

We conducted a cross-sectional study using data from the Chinese Longitudinal Healthy Longevity Survey (2014 wave). Nineteen chronic diseases were used to measure multimorbidity. Self-reported nighttime sleep duration and sleep quality were used as exposures. Multivariate logistic regression analysis and stratification were used to explore the association between sleep behavior and multimorbidity in different groups. Restrictive cubic splines were used to examine the exposure-response relationship.

RESULTS

Compared with those with nighttime sleep duration between 7 and 9 h, participants with shorter (<7 h) and longer (>9 h) sleep duration had a higher prevalence of multimorbidity (odds ratio [OR], 95% confidence interval [CI] were 1.38, 1.18-1.61 and 1.30, 1.09-1.56 respectively). Besides, poor sleep quality (OR = 2.25, 95% CI:1.82-2.72) and moderate sleep quality (OR = 1.35, 95% CI:1.16-1.58) were positively associated with multimorbidity.

CONCLUSIONS

Although the role of sleep behavior in multimorbidity has not been fully understood, this study highlighted the importance of normal nighttime sleep duration and good sleep quality in preventing multimorbidity.