If you are just tuning in, you can catch the first four articles in this series here:
- Sleep & Pain ... or is it Pain & Sleep
- Sleep and Weekend Recovery: Can You Catch Up?
- Sleep and Exercise: A Reciprocal Relationship
- Sleep and Mental Health: A Deep Connection
Emerging research highlights sleep as a powerful determinant of cardiovascular health. Insufficient or poor-quality sleep has been linked to hypertension, atherosclerosis, heart failure, and stroke. A 2019 statement from the American Heart Association emphasised the inclusion of sleep duration and quality as part of cardiovascular risk assessments (St-Onge MP et al. Circulation. 2016;134(18):e367–e386).
Short sleep duration (i.e., < 6 hours) has been associated with elevated blood pressure, increased sympathetic nervous system activity, and impaired endothelial function. When we sleep, our blood pressure drops, giving our heart and associated plumbing some downtime and time for necessary repairs. A prospective study by Wang et al. found that individuals with chronic sleep deprivation had a 45% higher risk of developing cardiovascular disease (Wang Y et al. J Am Coll Cardiol. 2019;73(2):134–144). Long sleep (i.e., > 9 hours) also appears to increase risk, especially when combined with poor sleep quality or fragmented sleep. So just like Goldilocks, the aim is to get it 'just right'.
Obstructive sleep apnea (OSA), a condition marked by intermittent breathing pauses during sleep, is a major contributor to cardiovascular morbidity. Effective treatment of OSA with CPAP has been shown to reduce blood pressure and lower the risk of cardiovascular events (Marin JM et al. Lancet. 2005;365(9464):1046–1053). Around 30% of patients with OSA can experience improvements in symptoms through sleep posture training, with the goal of reducing the amount of time spent in a supine position.
Additionally, irregular sleep patterns, such as shifting bedtimes and wake times, may contribute to circadian misalignment and metabolic dysregulation. A 2020 study report in Sleep found that greater sleep variability was associated with increased arterial stiffness and elevated resting heart rate (Huang T et al. Sleep. 2020;43(7):zsz309).
In conclusion, sleep is not merely a mental and physical restorative process but a regulator of cardiovascular function. Maintaining regular sleep patterns, addressing sleep disorders such as OSA, and aiming for 7–9 hours of quality sleep per night does play a crucial role in protecting our heart health.