Melatonin improves sleep quality

The title will hardly come as a surprise to many. The real novelty is that a dosage of only 2.5 mg of melatonin daily - can overcome the side effects of blood pressure medication which reduce the quality of sleep.

The blood pressure medication in question are the so-called beta blockers, that work by blocking certain cell receptors, which among other things means that the blood pressure and the heart rate decreases. This type of medicine is widespread. In the United States alone about 22 million Americans take beta blockers alone or with other medicine against various cardiovascular diseases. However, beta-blockers also blocks nerve signals to the pineal gland, whereby the nocturnal production of the hormone melatonin is reduced.

As there is also evidence that supplements of melatonin may improve sleep in older people with insomnia and with a low production of melatonin in the body, a group of researchers wanted to investigate whether supplements of melatonin could improve sleep quality in patients on continuous treatment with beta-blockers.

15 participants with hypertension as their only health issue completed the double-blind randomized controlled trial. To begin with they had their sleep quality measured in a sleep laboratory using polysomnography which is a comprehensive registration of the bio-physiological changes that occur during sleep. The participants received 2.5 mg melatonin or placebo in the form of 2.5 mg microcrystalline cellulose together with their beta blockers one hour before bedtime every night for three weeks. To assess the sleep quality in the home researchers used a simpler method called actigraphi, where the movements of the arms and legs are recorded during sleep by means of a bracelet. At the end of the test period, participants again had their sleep quality measured in the laboratory.

Improvements

The study showed that people taking beta-blockers easily can improve their sleep quality significantly with supplements of melatonin. Compared to the placebo group the melatonin group improved their total sleep time by an average of 36 minutes. The proportion of effective sleep was improved by 7.6%. The time it took to reach sleep stage 2 was reduced by 14 minutes. Melatonin increased sleep stage 2 with entire 41 minutes. In fact these improvements lasted some time after cessation of melatonin.

Conclusion

Although only 15 persons attended, the study was of high quality. The researchers conclude their research paper with an academic understatement, as they write that their research may help to develop countermeasures for sleep disorders related to beta-blocker therapy. It is an understatement, because the alternative to melatonin is conventional sleeping pills which becomes less effective with continual use and also increases dependence and tendency to abuse.

Ref.

Scheer FAJL, et al. Repeated Melatonin Supplementation Improves Sleep in Hypertensive Patients Treated with Beta-Blockers: A Randomized Controlled Trial. SLEEP 2012;35(10):1395-1402.