Association of napping with incident cardiovascular events in a prospective cohort study

Abstract

<jats:sec><jats:title>Objective</jats:title><jats:p>There is controversy regarding the effect of napping on cardiovascular disease (CVD), with most studies failing to consider napping frequency. We aimed to assess the relationship of napping frequency and average nap duration with fatal and non-fatal CVD events.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>3462 subjects of a Swiss population based cohort with no previous history of CVD reported their nap frequency and daily nap duration over a week, and were followed over 5.3 years. Fatal and non-fatal CVD events were adjudicated. Cox regressions were performed to obtain HRs adjusted for major cardiovascular risk factors and excessive daytime sleepiness or obstructive sleep apnoea.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>155 fatal and non-fatal events occurred. We observed a significantly lower risk for subjects napping 1–2 times weekly for developing a CVD event (HR 0.52, 95% CI 0.28 to 0.95) compared with non-napping subjects, in unadjusted as well as adjusted models. The increased HR (1.67, 95% CI 1.10 to 2.55) for subjects napping 6–7 times weekly disappeared in adjusted models (HR 0.89, 95% CI 0.58 to 1.38). Neither obstructive sleep apnoea nor excessive daytime sleepiness modified this lower risk. No association was found between nap duration and CVD events.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>Subjects who nap once or twice per week have a lower risk of incident CVD events, while no association was found for more frequent napping or napping duration. Nap frequency may help explain the discrepant findings regarding the association between napping and CVD events.</jats:p></jats:sec>

Sleep health composites are associated with the risk of heart disease across sex and race

“… Dimension Self-report sleep health composite Actigraphy/self-report sleep health composite Variable Assessment / Item Range M ( SD ) Variable Assessment / Item Range M ( SD ) Regularity 8 , 37 Sleep Debt Difference between workday sleep duration and non-workday sleep duration − 13 to 12 min 0.58 (1.12) Irregularity of Sleep Midpoint Standard deviation (SD) of sleep midpoint 0 to 9.97 SDs 0.84 (0.83) Satisfaction 8 , 25 , 44 Trouble Falling Asleep Have trouble falling asleep 1: Sometimes, Often, or Almost Always; 0: Rarely or Never Variables Summed: 0–4 1.84 (1.45) Pittsburgh Sleep Quality Index (PSQI) During the past month, how would you rate your sleep quality overall? 0 (Very Good) to 3 (Very Bad) 1.01 (0.68) Nocturnal Awakenings Wake up during the night and have difficulty going back to sleep Early Awakenings Wake up too early in the morning and be unable to get back to sleep Unrested Upon Waking Feel unrested during the day, no matter how many hours of sleep you had Alertness 38 Nap Frequency During a usual week, how many times do you nap for 5 min or more? 0 to 13 times 2.01 (2.52) Alertness (Diary) ...…”

Risk of Developing Metabolic Syndrome Is Affected by Length of Daily Siesta: Results from a Prospective Cohort Study

“…It is often perceived as a cultural practice of Mediterranean and Asian nations, but any review of the evidence reveals that it is far more widespread. Large studies estimate that more than 28% of the British populace take afternoon naps [1]-a figure which climbs above 40% in Switzerland, the Nordic countries, and the United States of America [2][3][4][5][6]. In this light, the siesta can be reconsidered a modern phenomenon, coinciding with the global reduction in night-time sleep hours and increased use of electronic devices, as well as the dominant neoliberal emphasis on economic productivity and trends that encourage working from home.…”

“How does Austria sleep?” self-reported sleep habits and complaints in an online survey

“…Generally, a sleep duration between 7 and 9 h has been recommended for adults [19], while short (< 6 h) and long (> 9 h) sleep has been associated with increased mortality and morbidity [20,21]. Although it is still unclear whether there might be a causal relationship between long sleep duration and mortality, it seems more likely that people who sleep unusually long suffer from chronic diseases or disorders such as sleep apnea resulting in non-restorative sleep [22][23][24].…”