Poor sleep linked to years of poor cardiovascular health

Poor sleep could lead to between two and seven years worth of heightened heart disease risk and even premature death, according to a new study led by researchers at the University of Sydney in collaboration with Southern Denmark University.

The study analysed data from over 300,000 middle-aged adults from the UK Biobank and found that different disturbances to sleep are associated with different durations of compromised  cardiovascular health later in life compared to healthy sleepers.

In particular, men with clinical sleep-related breathing disorders lost nearly seven years of cardiovascular disease-free life compared to those without these conditions, and women lost over seven years. Importantly, even general poor sleep, such as insufficient sleep, insomnia complaints, snoring, going to bed late, and daytime sleepiness is associated with a loss of around two years of normal heart health in men and women.

“Anyone who’s had a few rough nights of sleep knows how it can lead to bad mood and not feeling one’s best. Our research shows that, over time, regular poor sleep can lead to significantly compromised cardiovascular health in middle and old age, said Professor Emmanuel Stamatakis from the Charles Perkins Centre and Faculty of Medicine and Health, senior author of the paper in BMC Medicine.

“Sleep apnoea is well known to increase the risk of cardiovascular disease and other chronic conditions, but these findings are a wake-up call that poor sleep in general can pose significant risk to heart health.”

The team used an established composite sleep score comprising self-reported sleep duration, insomnia complaints, snoring, daytime sleepiness and whether the person was a night owl or an early bird to come up with three sleep categories: poor, intermediate, and healthy at age 40, and compared this with their overall cardiovascular disease-free health expectancy.

By combining the study participants’ self-reported data with clinical data from their doctors in the two years preceding the study, the researchers were able to compare health outcomes for self-reported sleep patterns and clinically diagnosed conditions such as sleep-related breathing disorders.

Women with poor sleep were likely to experience two years more of compromised cardiovascular health compared to healthy sleepers, while men experienced more than two years. Intermediate sleepers lost almost one year of heart disease-free life among women, and men lost slightly more.

This means that snoring and trouble falling asleep or staying asleep can be a warning sign of potential health issues in the future.

“While the average life expectancy of the UK study participants is around 80 years, people with clinically diagnosed sleep-related breathing disorders like sleep apnoea lost over seven years of cardiovascular-disease free life,” said the study’s lead author Dr Bo-Huei Huang, an epidemiologist recently graduating from the Charles Perkins Centre and Faculty of Medicine and Health.

Professor Peter Cistulli, the ResMed Chair of Sleep Medicine at the Charles Perkins Centre and Royal North Shore Hospital, said that these findings are significant because they extend the findings of previous studies linking poor sleep to important health outcomes.

“Sleep is a vital biological function that has been under-appreciated in public health policy to date. It’s gratifying that these findings shine a light on the importance of sleep, and the need for it to be recognised as a pillar of good health, alongside physical activity and nutrition. The time is right to ensure that sleep is recognised in public health policy,” said Professor Cistulli.

Declaration: This research has been conducted using the UK Biobank Resource under Application Number 25813. The authors gratefully thank all the participants and professionals contributing to the UK Biobank. In addition, the authors acknowledge the Sydney Informatics Hub and the Artemis University of Sydney’s high-performance computing cluster Artemis for providing the computing resources and support to complete the research reported in this paper.

Dr Bo-Huei Huang was a PhD student supported by the Taiwanese Ministry of Education and the University of Sydney. Emmanuel Stamatakis is funded by the Australian National Health and Medical Research Council through an Investigator Grant Level 2 (APP1180812). No conflict of interest was declared as the funding sources had no involvement in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the article for publication.

UK Biobank is a large-scale biomedical database and research resource containing anonymised genetic, lifestyle and health information from half a million UK participants. UK Biobank’s database, which includes blood samples, heart and brain scans and genetic data of the volunteer participants, is globally accessible to approved researchers who are undertaking health-related research that’s in the public interest.