For a long time now I’ve been a fan of sleep. Not just because of its relatively immediate impact on energy levels and sense of wellbeing, but also because of the research which links adequate sleep with improved health in the long term. Short sleep times have, for instance, been linked with an increased risk of heart disease. One such study as published this week in the Archives of Internal Medicine. The population being studied comprised more than 1200 Japanese men and women with an average age of 70. The group was followed for an average of just over 4 years.
All the members of this group were suffers of hypertension (high blood pressure). The individuals were assessed to see how their blood pressure at night compared with levels during the day. Generally, blood pressure falls at night. However, in some of the group blood pressure rose slightly (referred to in the study as a ‘riser pattern’).
Overall, individuals sleeping for less than 7.5 hours a night, compared to those sleeping longer, were found to be at a 68 per cent increased risk of cardiovascular disease (heart attack and stroke), death from cardiovascular disease, or what is known as sudden cardiac death. The greatest risk appeared to be for those who in addition to sleeping less than 7.5 hours, also exhibited the ‘riser pattern’ in terms of their blood pressure. Compared to those without this pattern who also slept for long, this subgroup were about four and half times more likely to suffer from one of the endpoints monitored in the study.
It is not possible from epidemiological studies to know if lower sleep times increases risk of cardiovascular disease and death, or these things are just associated with each other. However, there is at least some reason to think there is a causal link. Lack of sleep has been noted to increase activity in part of the nervous system known as the sympathetic nervous system. In turn, this can increase blood pressure. Suboptimal sleep has also been shown to induce changes which predispose towards insulin resistance (a precursor of type 2 diabetes and a risk factor for cardiovascular disease). And finally, lack of sleep has also been shown to cause a rise in the level of the inflammatory marker C reactive protein that is also associated with an increased risk of cardiovascular disease.
What this mean is that is at least some evidence which explains how a lack of sleep might increase the risk of cardiovascular disease. And all-in-all, there is good reason to believe not scrimping of sleep may add years to our life as well as life to our years.
Eguchi K, et al. Short Sleep Duration as an Independent Predictor of Cardiovascular Events in Japanese Patients With Hypertension. Arch Intern Med. 2008;168(20):2225-2231
I wonder whether there is an element of causality in the other direction. I certainly find that the more unhealthy my lifestyle, the better I sleep. Drinking alcohol, eating bad food and not exercising enough seem to make my body sluggish and sleeping for longer becomes easier. When I am fit and healthy, I have real problems with waking up early and often get fewer than 7 hours per night for prolonged periods….
I suppose you could also conclude that Japanese men with hypertension are at a greater risk of sleep disorders… which comes first?
Sleep! Somebody tell me how to get it. I used to sleep like a log, now I’ve got older, the sleep hormone has abandoned me and all this guff about older people needing less sleep because of less exercise is wrong, I do a lot of exercise, go to bed tired and then find myself lying there.
Jean I seem to remember reading that older people sleep exactly as you describe. It’s not that they need less sleep it’s that they don’t get enough deep sleep. Which is why they tend to nod off during the day. All I can suggest is that one tries to accept this and work around it. I’m wonder if you could tell yourself that you need a nap or two during the day then life might be more bearable?
Like Jean above, just how do i get 7.5 hours these days???? I too always slept like the proverbial log, but since hitting 58 and the menopause I spend half the night awake and worrying about not getting enough sleep and consequently whethet this lack of sleep is going to kill me!! I too have a pretty physical life eat well bla bla bla, but if only could actually sleep a bit more..
I do so agree with the non sleepers! This has been my problem for years and years – in fact since my younger son chose the wrong GCSE subjects and would not listen to reason and I am now 73. What to do – I wake up at 2am and by 3 am I feel so depressed and desperate. Have tried homeopathy with some success but that only works well on an isolated occasion, not every night. I think emotional freedom technique (tapping acupressure points) is helpful and might work better if I could organise myself around how often and when to do it. Yes my blood pressure is a little higher than it should be but has been responding to daily vigorous walks for 20-30 mins or so and that seems to help the sleeping sometimes too. Does anyone have any better ideas!?