Considered to be a privilege in current times, midday naps are said to be beneficial for health as they not only normalise blood pressure levels, they may probably also decrease the number of required antihypertensive medications.
These are the findings of a study presented at ESC Congress in Athens, Greece. Dr Manolis Kallistratos, a cardiologist at Asklepieion Voula General Hospital in Athens, Greece, who presented the study, set out to find answer to the question of whether the habit of taking an afternoon nap is just customary or is it also beneficial.
Citing examples of two influential UK Prime Ministers, Dr Kallistratos said that both Winston Churchill and Margaret Thatcher were proponents of midday naps and rightly because their study has revealed that such naps seem to lower blood pressure levels.
The main aim of the study was to assess the effect of midday sleep on blood pressure (BP) levels in hypertensive patients. For the study, researchers included 386 middle aged patients (200 men and 186 women, average age 61.4 years) with arterial hypertension.
Researchers measured midday sleep time (in minutes), blood pressure in office, 24 hour ambulatory BP, pulse wave velocity, lifestyle habits, body mass index (BMI) and a complete echocardiographic evaluation including left atrial size. BP measurements were reported as diastolic and systolic BP.
Post these measurements, researcher adjusted for factors that could influence BP such as age, gender, BMI, smoking status, salt, alcohol, exercise and coffee. Analysis revealed that midday sleepers had 5 per cent lower average 24 hour ambulatory systolic BP (6 mmHg) compared to patients who did not sleep at all midday. Their average systolic BP readings were 4 per cent lower when they were awake (5 mmHg) and 6 per cent lower while they slept at night (7 mmHg) than non-midday sleepers.
Dr Kallistratos said: “Although the mean BP decrease seems low, it has to be mentioned that reductions as small as 2 mmHg in systolic blood pressure can reduce the risk of cardiovascular events by up to 10 per cent.”
Further, researchers also found that those who took a midday nap had 11 per cent lower pulse wave velocity levels and left atrium diameter was 5 per cent smaller.
“These findings suggest that midday sleepers have less damage from high blood pressure in their arteries and heart,” said Dr Kallistratos.
The duration of midday sleep was associated with the burden of arterial hypertension. Patients who slept for 60 minutes midday had 4 mmHg lower average 24 hour systolic BP readings and a 2 per cent higher dipping status5 compared to patients who did not sleep midday. Dippers had an average of 17 minutes more midday sleep than non-dippers.
Dr Kallistratos said: “Our study shows that not only is midday sleep associated with lower blood pressure, but longer sleeps are even more beneficial. Midday sleepers had greater dips in blood pressure while sleeping at night which is associated with better health outcomes. We also found that hypertensive patients who slept at noon were under fewer antihypertensive medications compared to those who didn’t sleep midday.”
He concluded: “We found that midday sleep is associated with lower 24 hour blood pressure, an enhanced fall of BP in night, and less damage to the arteries and the heart. The longer the midday sleep, the lower the systolic BP levels and probably fewer drugs needed to lower BP.”