Older hypertensive people may benefit from melatonin

Many older people sleep poorly and tend to have elevated blood pressure. Luckily, supplementation with melatonin seems to correct both problems. Melatonin can even improve sleep in people who take beta-blockers for high blood pressure. So what is melatonin, and why is this substance particularly useful for older people?

Melatonin is considered a hormone as well as a signaling substance. It plays a key role in controlling our 24-hour clock (circadian rhythm), and it controls a number of other vital processes in the body. Melatonin is produced by a small gland called the pineal gland that is localized at the center of the brain. Blood levels of melatonin normally rise in response to nightfall, and levels peak between 2 and 4 A.M.
The pineal gland shrinks in size with increasing age due to calcification. This causes the melatonin production to decrease. The melatonin production in a person in his sixties is down to around half of what it was in his twenties. Not only does this affect quality of sleep, it also affects, to a greater or smaller extent, blood pressure and other functions where melatonin is involved.

Melatonin significantly lowers blood pressure

In a study that is described in News Medical Life Sciences, researchers looked at 63 seniors with an average age of 80 years. The first week was spent collecting data on blood pressure. For the two following weeks, each participant got a 1.5 mg melatonin supplement every evening at 10.30 P.M.
After that, another week was spent collecting blood pressure data. It turned out that the melatonin supplements lowered blood pressure levels significantly. Apparently, this had something to do with the time of day where the participants took their supplement. As it turned out, melatonin’s ability to lower blood pressure peaked between 3 and 8 A.M., which is the time period
that involves the greatest risk of suffering a heart attack or stroke, according to the scientists.
Systolic blood pressure dropped by 8 mmHg, while diastolic blood pressure dropped by 3.5 mmHg.
In addition, the participants’ average blood pressure dropped more during the second week of supplementation, suggesting that melatonin has a gradually increasing impact on blood pressure levels.

Melatonin as part of preventing and treating hypertension

Based on the above-mentioned study, melatonin supplements may help normalize several processes that are affected negatively by circadian rhythm disturbances and poor sleep, such as elevated blood pressure, irregular heart rhythm, and body temperature. The scientists did not observe any of these improvements among 34 placebo-treated seniors who served as controls.
The researchers concluded that melatonin supplementation may be highly useful for elderly people suffering from hypertension. It is also possible to combine melatonin and anti-hypertensive medicine for controlling blood pressure under the guidance of a physician. As the scientists see it, we are looking at a whole new way of preventing and treating hypertension in older people.

Circadian rhythm disturbances and insomnia among the elderly

The older we are, the greater our risk of sleep disturbances. As mentioned earlier, insomnia may be a result of the declining melatonin production. Around half of all people aged 65 years and older report sleeping problems. Many older people often feel tired earlier in the evening and wake up earlier in the morning.
They also find that they have a decreased amount of deep sleep, and the deep sleep may vanish entirely in people, who are very old. The superficial sleep explains why so many people wake up several times during the night. In fact, lack of deep sleep has a number of physiological and psychological consequences that can affect blood pressure and speed up the ageing process.
Nonetheless, melatonin supplements can compensate for the age-related drop in melatonin production, thereby improving sleep quality and correcting various physiological processes that depend on melatonin.

Improves sleep quality in people who take beta-blockers

Millions of people take beta-blockers for elevated blood pressure, heart rhythm disturbances, and angina attacks (chest pain), but this class of drugs is associated with several side effects. This is because they block nerve signals to the pineal gland, leading to decreased melatonin production and impaired sleep quality.
Melatonin supplements, however, may improve the quality and duration of sleep in patients who take beta-blockers for hypertension. This was shown in a double-blind placebo-controlled study of 15 patients, where half the participants got 2.5 mg of melatonin, while the other half got matching placebo. Every night for three weeks one hour before bedtime, both groups took their pills together with their beta-blockers. The participants in the group that took melatonin fell asleep faster compared with the participants in the placebo group. Moreover, the accumulated sleep duration in the melatonin group increased by 36 minutes on average, while the amount of deep sleep increased by 7.6 percent. These improvements persisted for some time after they discontinued their melatonin supplementation. The study is published in the science journal SLEEP.

References:

Bentham Science Publishers. Melatonin can be of great value for elderly people suffering from hypertension. News Medical Life Science. 2016
http://www.news-medical.net/news/20160518/Melatonin-can-be-of-great-value-for-elderly-people-suffering-from-hypertension.aspx

Nanna Witting. Søvnløshed blandt ældre. Sundhed.dk 2011

Pierpaoli Walter, Regelson William. The Melatonin Miracle. Simon and Schuster 1996