Sleep duration is an essential factor influencing cardiovascular health. An individual’s inadequate or excess sleep duration may result in several cardiovascular diseases such as hypertension, coronary heart disease, heart attack, and stroke.

The risk of CVD increases with the worsening of sleep duration. However, the underlying mechanisms of the relationship between sleep duration and CVD remain poorly elucidated. This article aims to provide insights into the correlation between sleep duration and the risk of cardiovascular diseases.

The recommended sleep duration per age group

The National Sleep Foundation recommends adequate sleep duration per day based on an individual’s age group. The following table summarizes the recommended sleep duration for each age group:.

Age Group	Recommended Sleep Duration
0-3 months	14-17 hours
4-11 months	12-15 hours
1-2 years	11-14 hours
3-5 years	10-13 hours
6-13 years	9-11 hours
14-17 years	8-10 hours
18-25 years	7-9 hours
26-64 years	7-9 hours
65 years and above	7-8 hours

The relationship between sleep duration and cardiovascular diseases

Sleep deprivation, as well as prolonged sleep duration, is a significant risk factor for cardiovascular diseases.

Studies suggest that an individual’s inadequate sleep duration leads to hypertension, which puts the individual at risk of heart disease, heart attack, and stroke. According to a study, individuals who sleep for less than six hours a day have a 48% higher risk of developing or dying of heart disease and 15% more likely to develop or die from stroke than individuals who sleep six to eight hours daily.

Conversely, sleeping for more than eight hours a day increases the risk of cardiovascular diseases by 38%.

Another study also showed that individuals who sleep for less than six hours or more than nine hours a night had a higher risk of coronary heart disease.

Atrial fibrillation, a type of arrhythmia that increases the risk of stroke and heart failure, is more prevalent among individuals with sleep apnea, which occurs due to irregular breathing during sleep. The risk of atrial fibrillation is 2.4 times higher among individuals with insufficient sleep duration of less than six hours a day.

Mechanisms underlying the relationship between sleep duration and cardiovascular diseases

The underlying mechanisms linking sleep duration and cardiovascular diseases are still under investigation. However, some hypotheses explain the relationship between short and prolonged sleep duration and the risk of CVD:.

Hypertension

Hypertension is a significant risk factor for cardiovascular diseases. The sympathetic nervous system plays a critical role in regulating blood pressure during sleep.

Sleep disturbances, including insomnia and sleep apnea, activate the sympathetic nervous system, which leads to hypertension. Studies suggest that adequate sleep duration maintains blood pressure levels and reduces the risk of hypertension and consequently heart disease, stroke, and heart attack.

Inflammation

Inflammation is associated with cardiovascular diseases. Prolonged sleep deprivation is linked to higher levels of C-reactive protein, a molecule that triggers inflammation.

An elevated level of C-reactive protein in the body is associated with arterial damage, heart attack, and stroke, among other cardiovascular diseases. Conversely, adequate sleep duration is associated with lower levels of C-reactive protein, which reduces the risk of inflammation and thereby decreases the chance of developing cardiovascular diseases.

Metabolic dysregulation

Metabolic dysregulation is also associated with cardiovascular diseases. Studies suggest shorter sleep durations or longer durations than the recommended levels are associated with obesity and diabetes.

Insulin resistance, a condition common with diabetes, increases the risk of heart disease and stroke.

Conclusion

Cardiovascular diseases remain a significant global health issue. Studies suggest that the duration and quality of an individual’s sleep heavily influence the risk of cardiovascular diseases.

Individuals who sleep for less than six hours or more than eight hours daily have a higher risk of developing or dying from cardiovascular diseases than those who sleep six to eight hours daily. The underlying mechanisms that explain the relationship between sleep duration and CVD remain under investigation. However, hypertension, inflammation, and metabolic dysregulation are hypothesized as potential factors influencing this correlation.

Individuals should follow the recommended sleep duration per age bracket and avoid sleep deprivation and prolonged sleep duration to maintain good cardiovascular health.