In a small study of nearly 100 residents of a facility for the elderly, Russian researchers found that low doses of melatonin every night for two weeks reduced participants’ blood pressure levels and rendered circadian rhythms “less irregular.” While the study, albeit modest in size, has both strengths and weaknesses (for example, it utilized a control group but did not appear to “blind” the researchers to treatment/nontreatment conditions), the findings reflect patterns that have been well established by researchers over the years concerning melatonin and circadian rhythms. We’re concerned that the release doesn’t point out the serious complications that can arise when taking melatonin with other drugs, particularly since the elderly are the most likely to be on multiple medications, including drugs for high blood pressure.
Among the frustrations of aging is increased difficulty sleeping, driven in part by fluctuations in blood pressure levels. This small, brief study does not establish whether melatonin is of value in treating either insomnia or fluctuating blood pressure. It is unclear whether the physiologic changes observed in this short study will translate to any patient-level outcomes that matter.
The release doesn’t mention cost. Melatonin is widely available over-the-counter and a range of costs should be reported. According to GoodRX, a bottle of 100 1mg melatonin tablets cost around $7.
(We acknowledge that the study was conducted in a country that has a different health system including different price supports. But since the news release is aimed at a U.S. audience, the cost criteria — as well as availability and alternatives that apply in the US but not elsewhere — are fair game.)
We rate this a Satisfactory because the release provides the absolute decrease in BP that was achieved in 63 participants. However, the way the benefit was quantified may not be useful to readers. The statement: “Nighttime and morning BP decreased more profoundly on average -8/3.5 mm Hg for SDP/DBP, respectively” may be too technical for most readers.
There is clearly a downside to any supplement use, particularly in older people who may already be on multiple interacting medications.
Although melatonin is probably safe for many adults, according to the University of Maryland Medical Center, a physician should be consulted before taking melatonin if you’re already taking medications for high blood pressure, antidepressants and blood thinners, among others.
A Web MD article states that melatonin can worsen symptoms in those suffering from bleeding disorders, diabetes, and seizures, and, perversely, may increase blood pressure levels in individuals taking medication to control those levels. Given the availability of melatonin supplements, ignoring the downsides for individuals with these common health problems is significant.
Although the news release offers some details about the study design, including the length of the study and the dose of melatonin used, it offers no information about the limitations of the study. Fewer than 100 individuals were involved, and these seniors all resided in the same facility in Russia. Three weeks is a relatively short time period, making longer term predictions difficult. And it appears that the researchers knew who was getting melatonin and who was not (in the case of the control group) and, among those receiving the supplement, when they received it and when they did not. These are limiting factors that detract from the evidence.
The news release is correct to note that circadian rhythms in the elderly get disrupted and can make getting a good night’s sleep more challenging. But should we regard this process as an illness requiring treatment? Those with hypertension should certainly care, but it is not clear that waking up more often during a night qualifies as a medical problem for many older individuals.
We found this quote a bit troubling: “The older we get, the more likely our circadian rhythms are disrupted. For example, blood pressure (BP), not only tends to increase but as well become more irregular. Luckily, as we show in our research, melatonin helps to ameliorate both trends.” This ‘process’ of blood pressure variability may in fact be normal physiology and is not necessarily the culprit for poor sleep.
The release is written as if the lead researchers wrote it themselves since the text contains no citations to sources but does offer the occasional second-person pronoun (“we”). The text contains no references to funding sources or possible conflicts of interest.
The only mention of alternatives occurs in the last sentence, which mentions “basic medication” for hypertension sufferers and offers up circadian pacemakers as “a new strategy in the treatment of hypertension.”
There are established treatments for people with hypertension and for those with insomnia. The former may range from changes in diet and the addition of exercise to a variety of medications to manage blood pressure. When insomnia becomes a regular occurrence, some people get help from behavioral changes (including diet, exercise and stress reduction) or a variety of prescription or over-the-counter sleep aids that are available.
Melatonin supplements are available almost everywhere.
The news release doesn’t make a claim to novelty, but then it shouldn’t as this study doesn’t appear to offer anything new. Melatonin’s main job in the body is to regulate night and day cycles or sleep-wake cycles. Many researchers have explored the effects of melatonin supplements, and one 2010 review noted that its use was well established “especially” for sleep disorders, including those related to aging. Much research has also determined that melatonin reduces night-time blood pressure levels in those with hypertension.
The news release concludes with cheerleading on behalf of melatonin use. The claim that “melatonin can be of great value” for older folks with hypertension is more than a stretch based on the limited evidence.