Self-reported sleep duration and daytime napping are associated with renal hyperfiltration and microalbuminuria in an apparently healthy Chinese population

Association between triglyceride to high-density lipoprotein cholesterol ratio and microalbuminuria in the Chinese population

The evidence for the association between the triglyceride (TG) to high-density lipoprotein cholesterol (HDL-c) ratio and the risk of developing microalbuminuria is still limited in the Chinese population. Therefore, our research will endeavor to explore the relationship between the two. The cross-sectional survey enrolled 32,877 general population from eight regional centers in China. If the urinary albumin-creatinine ratio (UACR) ≥ 30 mg/g, it was considered microalbuminuria. The dependent variable in the study was microalbuminuria, while the independent variable was the TG/HDL-c ratio. A binary logistic regression model was utilized to examine the independent association between the likelihood of microalbuminuria and the TG/HDL-c ratio. A generalized additive model (GAM) and spline smoothing were employed to investigate non-linear relationships between these two variables. To confirm the findings and pinpoint important turning points, subgroup and threshold effect tests were performed. The average age of the study participants was 57.67 ± 9.29 years, with 22,052 (67%) females and 10,825 (33%) males. The ratio of TG/HDL-c had a median value of 1.06, while the UACR had a median value of 9.92 mg/g. The prevalence of microalbuminuria was 14.4%. Following covariate adjustment, the prevalence of microalbuminuria and the TG/HDL-c ratio showed a significant positive connection (OR = 1.17,95% CI 1.13-1.21). Interestingly, we discovered a non-linear relationship between the occurrence of microalbuminuria and the TG/HDL-c ratio. At a TG/HDL-c ratio of 0.911, we detected an inflection point, with ORs of 1.12 (95% CI: 1.08, 1.17) on the right side of the point and 1.89 (95% CI: 1.51, 2.36) on the left. Subgroup analyses further validated the results. Our research revealed a positive and non-linear connection between the TG/HDL-c ratio and the prevalence of microalbumin in Chinese individuals. The connection was especially robust when the TG/HDL-c ratio was below 0.911. Reducing TG or raising HDL-c levels in order to lower the TG/HDL-c ratio may significantly mitigate the risk of microalbuminuria.

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.

Association between daytime napping and incident arrhythmias: A prospective cohort study and mendelian randomization analysis

BACKGROUND

Emerging evidence has linked daytime napping with the risk of cardiovascular events. Cardiac arrhythmias are considered an early clinical stage for cardiovascular diseases. However, whether napping frequency is associated with incident arrhythmias remains unknown.

OBJECTIVE

This study aimed to prospectively investigate the association between napping frequency and cardiac arrhythmias.

METHODS

Daytime napping frequency was self-reported in response to touchscreen questionnaires. The primary outcomes were incident arrhythmias including atrial fibrillation/flutter (AF/Af), ventricular arrhythmia, and bradyarrhythmia. Cox regression analysis was conducted on the basis of 491,117 participants free of cardiac arrhythmias from the UK Biobank. The 2-sample mendelian randomization (MR) and 1-sample MR were used to ensure a causal effect of genetically predicted daytime napping on the risk of arrhythmias.

RESULTS

During a median follow-up of 11.91 years, 28,801 incident AF/Af cases, 4132 incident ventricular arrhythmias, and 11,616 incident bradyarrhythmias were documented. Compared with never/rarely napping, usually napping was significantly associated with higher risks of AF/Af (hazard ratio, 1.141; 95% CI, 1.083-1.203) and bradyarrhythmia (hazard ratio, 1.138; 95% CI, 1.049-1.235) but not ventricular arrhythmia after adjustment for various covariates. The 2-sample MR and 1-sample MR analysis showed that increased daytime napping frequency was likely to be a potential causal risk factor for AF/Af in FinnGen (odds ratio, 1.626; 95% CI, 1.061-2.943) and bradyarrhythmia in the UK Biobank (odds ratio, 1.005; 95% CI, 1.002-1.008).

CONCLUSION

The results of this study add to the burgeoning evidence of an association between daytime napping frequency and an increased risk of cardiac arrhythmias including AF/Af, ventricular arrhythmia, and bradyarrhythmia.

Association between napping and type 2 diabetes mellitus

As the incidence of type 2 diabetes mellitus (T2DM) is increasing rapidly and its consequences are severe, effective intervention and prevention, including sleep-related interventions, are urgently needed. As a component of sleep architecture, naps, alone or in combination with nocturnal sleep, may influence the onset and progression of T2DM. Overall, napping is associated with an increased risk of T2DM in women, especially in postmenopausal White women. Our study showed that napping >30 minutes (min) increased the risk of T2DM by 8-21%. In addition, non-optimal nighttime sleep increases T2DM risk, and this effect combines with the effect of napping. For nondiabetic patients, napping >30 min could increase the risks of high HbA1c levels and impaired fasting glucose (IFG), which would increase the risk of developing T2DM later on. For diabetic patients, prolonged napping may further impair glycemic control and increase the risk of developing diabetic complications (e.g., diabetic nephropathy) in the distant future. The following three mechanisms are suggested as interpretations for the association between napping and T2DM. First, napping >30 min increases the levels of important inflammatory factors, including interleukin 6 and C-reactive protein, elevating the risks of inflammation, associated adiposity and T2DM. Second, the interaction between postmenopausal hormonal changes and napping further increases insulin resistance. Third, prolonged napping may also affect melatonin secretion by interfering with nighttime sleep, leading to circadian rhythm disruption and further increasing the risk of T2DM. This review summarizes the existing evidence on the effect of napping on T2DM and provides detailed information for future T2DM intervention and prevention strategies that address napping.

Association of daytime napping with incidence of chronic kidney disease and end-stage kidney disease: A prospective observational study

BACKGROUND AND AIMS

Few studies have examined the relationship between daytime napping and risk of kidney diseases. We aimed to investigate the association of daytime napping with the incidence of chronic kidney disease (CKD) and end-stage kidney disease (ESKD). We also examined whether sleep duration modified the association of nap with CKD or ESKD.

METHODS

We recruited 460,571 European middle- to older-aged adults without prior CKD or ESKD between March 13, 2006, and October 1, 2010, in the UK Biobank. Sleep behavior data were obtained through questionnaires administered during recruitment. The analysis of the relationship between napping and the occurrence of CKD and ESKD utilized Cox proportional hazards regression models. The modification role of sleep duration on the effect of nap on CKD and ESKD was also examined.

RESULTS

After a mean follow-up of 11.1 (standard deviation 2.2) years, we observed 28,330 incident CKD cases and 927 ESKD cases. The daytime napping was associated with incident CKD (P for trend = .004). After fully adjusted, when compared with participants who did not take nap, those in sometimes and usually nap groups had higher risk of CKD. Nevertheless, the available evidence did not support a link between daytime napping and ESKD (P for trend = .06). Simultaneously, there was insufficient evidence suggesting that sleeping duration modified the association of daytime napping with incident CKD or ESKD.

CONCLUSION

Daytime napping was associated with an increased risk of CKD. However, the absence of conclusive evidence did not indicate a connection between daytime napping and ESKD.

Sleep Duration and Kidney Function - Does Weekend Sleep Matter?

Objective

Weekend sleep duration is linked to health issues, including mortality. However, how weekend sleep duration can impact chronic kidney disease (CKD) still needs to be understood. Therefore, we aimed to analyze how weekend sleep duration is associated with kidney function.

Methods

This is a cross-sectional study. Data were obtained from the 2017-2018 National Health and Nutrition Examination Survey. We included 5362 study participants and categorized them into nine subgroups by sleep duration (short: ≤6 hours, normal: 6-9 hours, and long: ≥9 hours) on weekdays and weekends and analyzed for the respective association with renal function using stratified multivariable linear regression.

Results

Weekend sleep duration for 9 hours or more was associated with decreasing estimated glomerular filtration rate (eGFR) levels by 2.8 to 6.4 mL/min/1.73 m2 among people with long to short weekday sleep duration compared with short weekday and weekend sleep durations (control group) after adjusting for demographic characteristics, body measurement, sleep quality, smoking, and comorbidities. The study population with short weekday sleep duration (sWK) and long weekend sleep duration (lWD) had the most significant decline in eGFR. For the study population with sWK, eGFR level significantly decreased by 1.1 mL/min/1.73 m2 as sleep duration on weekends increased by one hour.

Conclusion

The underlying mediators of lWD and CKD could be the dysregulation of human behaviors, metabolism, or biological functions. Longer weekend sleep duration was linked to a decrease in eGFR levels. It warrants further study to clarify the mediators.

Relationship between daytime napping with the occurrence and development of diabetes: a systematic review and meta-analysis

OBJECTIVE

To determine the relationship of napping with incident diabetes risk and glycaemic control in people with diabetes.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

MEDLINE (PubMed), EMBASE, Web of Science and the Cochrane Library were searched for studies published from database inception to 9 May 2023.

ELIGIBILITY CRITERIA

Observational studies reporting the relationship of napping with diabetes or glycaemic control in patients with diabetes in adult populations were included.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently screened the literature, extracted data and assessed the quality of the included studies. The results were reported as ORs and 95% CIs, which were pooled by using fixed and random effects models, and subgroup analyses were performed. The Grading of Recommendations Assessment, Development and Evaluation method was used to assess the quality of the evidence.

RESULTS

Forty studies were included in our review. Habitual napping was associated with an increased diabetes risk (OR 1.20, 95% CI 1.14 to 1.27) and poor glycaemic control in patients with diabetes (OR 2.05, 95% CI 1.55 to 2.73). Nap durations less than 30 min were unrelated to diabetes (OR 1.05, 95% CI 0.97 to 1.14). Nap durations of 30-60 min were associated with diabetes risk (OR 1.09, 95% CI 1.02 to 1.17), but there were differences in the subgroup analysis results. Nap durations of more than 60 min significantly increased the risk of diabetes (OR 1.31, 95% CI 1.20 to 1.44).

CONCLUSIONS

Napping is associated with increased diabetes risk and poor glycaemic control, and future research will need to confirm whether there are sex and regional differences. Nap durations of more than 60 min significantly increases the risk of diabetes, and the relationship between nap duration and glycaemic control in patients with diabetes needs to be further explored in the future.

PROSPERO REGISTRATION NUMBER

CRD42021292103.

Association between sleep parameters and chronic kidney disease: findings from iranian ravansar cohort study

INTRODUCTION

The relationship between sleep duration and chronic kidney disease (CKD) has received relatively little attention in the Kurdish community. Considering the ethnic diversity of Iran and the importance of the Kurdish community, the present study investigated the association between sleep parameters and CKD among a large sample of Iranian-Kurds.

METHODS

This cross-sectional study was conducted among 9,766 participants (Mage: 47.33, SD = 8.27, 51% female) from the Ravansar Non Communicable Disease (RaNCD) cohort study database. Logistic regression analyses were applied to examine the association between sleep parameters and CKD.

RESULTS

Results showed that prevalence of CKD was detected in 1,058 (10.83%) individuals. Time to fall asleep (p = 0.012) and dozing off during the day (p = 0.041) were significantly higher in the non-CKD group compared to the CKD group. Daytime napping and dozing off during the day in females with CKD were significantly more than males with CKD. A long sleep duration (> 8 h/day) was associated with 28% (95% CI: 1.05, 1.57) higher odds of CKD compared to normal sleep duration (7 h/d), after adjusting for confounding factors. Participants who experienced leg restlessness had a 32% higher probability of developing CKD than those who did not experience leg restlessness (95% CI: 1.03, 1.69).

CONCLUSION

Results suggest that sleep duration and leg restlessness may be associated with an increased likelihood of CKD. Consequently, regulating sleep parameters may play a role in improving sleep and preventing CKD.

Association between napping and 24-hour blood pressure variability among university students: A pilot study

Background

Blood pressure variability (BPV) has been reported to be a predictor of cardiovascular and some cognitive diseases. However, the association between napping and BPV remains unknown. This study aimed to explore the association between napping and BPV.

Materials and methods

A cross-sectional study including 105 university students was conducted. Participants' 24 h ambulatory blood pressure monitoring (24 h ABPM) were measured, and napping behaviors were investigated. BPV were measured by the 24 h ABPM, included standard deviation (SD), coefficient of variation (CV), and average real variability (ARV).

Results

Among the participants, 61.9% reported daytime napping. We found that nap duration was significantly associated with daytime CV of diastolic blood pressure (DBP) (r = 0.250, P = 0.010), nighttime CV of systolic blood pressure (SBP) (r = 0.217, P = 0.026), 24 h WCV of DBP (r = 0.238, P = 0.014), 24 h ARV of SBP (r = 0.246, P = 0.011) and 24 h ARV of DBP (r = 0.291, P = 0.003). Compared with the no napping group, 24 h WCV of DBP, daytime CV of DBP, and daytime SD of DBP were significantly higher in participants with napping duration >60 min. With multiple regression analysis we found that nap duration was an independent predictor for 24 h ARV of SBP (β = 0.859, 95% CI, 0.101-1.616, P = 0.027) and 24 h ARV of DBP (β = 0.674, 95% CI, 0.173-1.175, P = 0.009).

Conclusions

Napping durations are associated with BPV among university students. Especially those with napping durations >60 min had a significantly higher BPV than those non-nappers.

Association Between Sleep Duration and Albuminuria in Patients with Type 2 Diabetes: A Cross-Sectional Study in Ningbo, China

PURPOSE

Type 2 diabetes mellitus (T2DM) can lead to microvascular complications including diabetic kidney disease. Albuminuria is an important marker to diagnose kidney injury in T2DM patients and healthy sleep duration is important for maintaining good health in patients with T2DM. However, the association between sleep duration and albuminuria in T2DM patients is unclear. Thus, this study aimed to investigate the association between sleep duration and albuminuria in patients with T2DM in Ningbo, China.

METHODS

A cross-sectional study was conducted at National Metabolic Management Centre (MMC) - Ningbo First Hospital from March 2018 to February 2021. Adult patients with T2DM were included in the study. The sleep duration (daytime and nocturnal) was self-reported. Albuminuria was defined as the presence of urinary albumin-creatinine ratio ≥30 mg/g. Logistic regression analyses were performed to identify the association.

RESULTS

There were 2688 T2DM patients in the study. In the unadjusted model (1), the odds of albuminuria increased with the daytime sleep duration (31-60 minutes: OR 1.36, 95% CI 1.09-1.71; ≥61 minutes: 1.73, 1.33-2.24). Similarly, after adjusting for age and sex (model 2), the odds of albuminuria increased with the daytime sleep duration (31-60 minutes: 1.34, 1.07-1.68; ≥61 minutes: 1.69, 1.30-2.20). After adjusting for age, sex, physical activity, smoking, alcohol drinking, overweight/obesity, hypertension, hyperuricaemia, duration of T2DM, glycated haemoglobin, angiotensin-converting enzyme inhibitors/angiotensin receptor blocker usage and nocturnal sleep duration (model 3), the odds of albuminuria increased with the daytime sleep duration (31-60 minutes: 1.33, 1.04-1.71; ≥61 minutes: 1.71, 1.29-2.26). However, no relationship was found between nocturnal sleep duration and albuminuria.

CONCLUSION

Longer daytime sleep is found to be associated with albuminuria in patients with T2DM in Ningbo, China but no association is found between nocturnal sleep duration and albuminuria. The findings are exploratory, and there is a need for longitudinal studies on this topic.

Association between social capital and sleep duration among rural older adults in China

OBJECTIVE

Sleep disturbances are great challenges to older adults' health promotion. The study tested gender differences in the association between different dimensions of social capital and self-reported sleep duration of Chinese rural older adults.

DESIGN

The data of rural older adults were extracted from a national cross-sectional survey of the Chinese Longitudinal Healthy Longevity Survey (CLHLS) and analyzed in this study.

SETTING

CLHLS covered 23 provinces in China.

PARTICIPANTS

The 6552 rural respondents aged ≥65 years old were involved.

MAIN OUTCOME MEASURES

Generalized trust, informal social participation, formal social participation and social support were used to assess social capital. Self-reported sleep duration was measured as health outcome.

RESULTS

Low level of generalized trust had harmful effect on insufficient sleep (AOR 1.110, 95% CI 1.018-1.324), and having no formal or informal social participation was significantly positively associated with long sleep (AOR_formal 1.424, 95% CI 1.007-2.013; AOR_informal 1.241, 95% CI 1.016-1.516). Rural older female adults with no emotional social support had higher odds of insufficient sleep (AOR 1.502, 95% CI 1.258-1.978). Meanwhile, both informal and formal social participation showed inverse association with long sleep for females.

CONCLUSIONS

This study found the relationship between social capital, sleep duration and the gender differences in Chinese rural older adults. More targeted sleep disturbance interventions could be taken in social capital of rural older adults, and gender differences should be considered when making social capital-embedded health promotion policies and interventions.

Burnout, daytime sleepiness and sleep quality among technical-level Nursing students

Objective:

to evaluate the association of the burnout syndrome with daytime sleepiness and sleep quality among technical-level Nursing students.

Method:

a cross-sectional, analytical and quantitative study, conducted with 213 students from four technical Nursing courses in a city of Paraná, Brazil. Data collection was carried out using an instrument containing characterization information, the Maslach Burnout Inventory - Student Survey, the Epworth Sleepiness Scale and the Pittsburgh Sleep Quality Index. The data were analyzed using descriptive statistics and logistic regression.

Results:

the prevalence values of the burnout syndrome, excessive daytime sleepiness and poor sleep quality were 4.7%, 34.7% and 58.7%, respectively. Excessive daytime sleepiness significantly increased the chances of high emotional exhaustion (OR^adj: 5.714; p<0.001) and high depersonalization (OR^adj: 4.259; p<0.001). Poor sleep quality, especially sleep disorders, was associated with all dimensions of the syndrome (p<0.05).

Conclusion:

high levels of the burnout syndrome dimensions were associated with excessive daytime sleepiness and poor sleep quality. Educational institutions should include sleep hygiene and psychosocial support in their student health promotion programs.

Male renal functions are associated with serum short- and medium-chain chlorinated paraffins in residents from Jinan, China

BACKGROUND

Chlorinated paraffins (CPs) are contaminants ubiquitously detected in environmental samples, and reports addressing CPs in human samples are expanding. While CP exposure was suggested to impair kidney function by in vivo/in vitro experiments, epidemiological evidence is lacking.

OBJECTIVE

To examine the associations between serum total short-chain CP and medium-chain CP concentrations (∑SCCPs and ∑MCCPs) with human kidney function.

METHODS

The study samples were obtained from 387 participants living in Jinan, North China. We quantified ∑SCCPs and ∑MCCPs in serum samples and evaluated the kidney function of included subjects by estimated glomerular filtration rate (eGFR). The associations between serum ∑SCCPs, ∑MCCPs and eGFR were estimated using multivariable linear regression and logistic regression. The possible gender-dependent effects were studied by stratified analysis.

RESULTS

After adjusting for age, education, smoking status, drinking status, body mass index (BMI), family history of chronic kidney disease (CKD), fasting serum glucose, systolic blood pressure and diastolic blood pressure, higher concentrations of serum ∑SCCPs and ∑MCCPs were associated with higher male eGFR (β = 3.13 mL/min/1.73 m² per one ln-unit increase of serum ∑SCCPs, 95%CI: 1.72, 4.54, p = 0.016; β = 3.52 mL/min/1.73 m² per one ln-unit increase of serum ∑MCCPs, 95%CI: 1.89, 5.17, p = 0.011). Associations between serum ∑SCCPs, ∑MCCPs and female eGFR were null. Comparing higher (above the median serum CP levels) vs. lower exposure groups, serum ∑SCCPs and ∑MCCPs were associated with an elevated risk of glomerular hyperfiltration (GH, eGFR ≥ 135 mL/min/1.73 m²), which was associated with glomerular damage and represented as an early stage of chronic kidney disease (OR = 2.98; 95% CI: 1.24, 4.71 for SCCPs; OR = 3.25; 95% CI: 1.20, 5.29 for MCCPs).

CONCLUSIONS

Our study suggests that male serum ∑SCCPs and ∑MCCPs are associated with an increased risk of GH, indicating early-stage kidney impairment.

Poor sleep efficiency and daytime napping are risk factors of depersonalization disorder in female university students

Objectives

Depersonalization is characterized by feelings of detachment from reality and has been associated with anxiety and depression, both of which have a bi-directional relationship with sleep. To date, few studies have directly examined the potential relationship between sleep and depersonalization, which was the primary objective of our study.

Design/methods

A cross-sectional study of female, Emirati, university students (n = 100) was conducted. Participants completed the Pittsburgh Sleep Quality Index (PSQI), the Cambridge Depersonalization Scale (CDS) and the Hospital Anxiety and Depression Scale (HADS). Additionally, 36 of the 100 participants wore wrist actigraphy for two consecutive weekdays. Average sleep duration, and average sleep efficiency (SE; %) across the two nocturnal sleep episodes were calculated. Total number of sleep episodes were obtained from wrist actigraphy and sleep logs.

Results

A significant, positive relationship was observed between PSQI global score and CDS total score (r = 0.21, p = 0.04). Actigraphy-estimated average nocturnal sleep duration was not significantly associated with the CDS. Compared to nocturnal sleepers only, those who undertook daytime naps had almost three times the risk of meeting the criteria for depersonalization disorder (OR = 2.95, 95% CI: 1.04–8.41), after adjustment. For each 1% increase in SE a 23% decreased risk of depersonalization was observed (OR = 0.77, 95% CI: 0.61–0.96), after adjustment.

Conclusions

Sleep screening in young adults may help to ensure better detection and management of psychological health outcomes. Our findings need to be confirmed prospectively in larger samples and amongst different populations but reiterate the importance of sleep habits pertaining to mental health.

•

We show a novel relationship between depersonalization and sleep in a non-clinical sample.

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Actigraphy determined poor sleep efficiency was significantly associated with subjective reports of depersonalization.

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Daytime nappers were ~3 times more likely to report depersonalization symptoms and meet the diagnositic criteria.

Dimethylarginines in acute myocardial infarction: Association with lifestyle, sociodemographic, and somatometric factors

BACKGROUND

Recent findings associate asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) with the prognosis of acute myocardial infarction (AMI). The purpose of the current study was to associate patients' lifestyle, sociodemographic, and somatometric characteristics with the time course of ADMA and SDMA concentrations in the serum of AMI patients.

PATIENTS AND METHODS

In the serum of 66 AMI patients, ADMA, SDMA, troponin T, and C-reactive protein (CRP) were measured upon hospital admission (<24 h) and on the 3rd day following. Lifestyle, sociodemographic, and somatometric characteristics were obtained through a questionnaire, filled on patient discharge.

RESULTS

ADMA concentrations on the 1st day positively correlated with daily reported hours of sleep (+0.497, P < 0.001) and delivery or eating out frequency (+0.285, P = 0.02), whereas it negatively correlated with reported physical condition (-0.304, P = 0.013). A personal history of hypertension indicated higher 1st-day ADMA concentration (1.818 vs 1.568, P = 0.042). Age positively correlated with 1st-day SDMA (+0.320, P = 0.009). All of the biomarker concentrations were reduced on the 3rd day measurements (P < 0.001). Self-reported lifetime minimum BMI positively correlated with either absolute (r = +0.366, P = 0.009) or percentage (r = +0.262, P = 0.045) ADMA reduction. A daily sleep in 5-8-h range was inversely correlated with percentage (-0.410, P = 0.001) or absolute (r = -0.369, P = 0.002) SDMA reduction.

CONCLUSIONS

Modifiable factors such as BMI, eating habits, physical condition, and sleep seem to affect the baseline levels or time course of ADMA and SDMA in AMI patients. Changes in these factors may affect AMI prognosis by altering dimethylarginine levels.

Up in the Air: Evidence of Dehydration Risk and Long-Haul Flight on Athletic Performance

The microclimate of an airline cabin consists of dry, recirculated, and cool air, which is maintained at lower pressure than that found at sea level. Being exposed to this distinctive, encapsulated environment for prolonged durations, together with the short-term chair-rest immobilization that occurs during long-haul flights, can trigger distinct and detrimental reactions to the human body. There is evidence that long-haul flights promote fluid shifts to the lower extremity and induce changes in blood viscosity which may accelerate dehydration, possibly compromising an athlete’s potential for success upon arrival at their destination. Surprisingly, and despite several recent systematic reviews investigating the effects of jet lag and transmeridian travel on human physiology, there has been no systematic effort to address to what extent hypohydration is a (health, performance) risk to travelers embarking on long journeys. This narrative review summarizes the rationale and evidence for why the combination of fluid balance and long-haul flight remains a critically overlooked issue for traveling persons, be it for health, leisure, business, or in a sporting context. Upon review, there are few studies which have been conducted on actual traveling athletes, and those that have provide no real evidence of how the incidence rate, magnitude, or duration of acute dehydration may affect the general health or performance of elite athletes.