Melatonin is a hormone naturally produced by the body. It regulates the sleep-wake cycle. The substance is sold as a supplement, where it’s used for treating insomnia (although the evidence for its effectiveness isn’t strong). However, melatonin may have potential in treating various aspects of chronic kidney disease (CKD).
Melatonin and sleep disturbances in CKD patients
Melatonin has been the subject of numerous studies on CKD patients. For instance, patients with kidney disease, particularly those undergoing dialysis, often suffer from sleep disturbances. A 2012 paper described how the hormone could play a role in restoring the circadian rhythms of people with CKD.
According to the study, these individuals frequently have trouble sleeping.
“Between 30% and 80% of individuals with end stage renal disease report disturbed sleep. A population study of daytime hemodialysis patients showed that 60% of these patients experienced subjective sleep problems. Patients on daytime hemodialysis and patients with CKD both have reduced total sleep time and reduced sleep efficiency in comparison with healthy subjects,” wrote the researchers.
Many factors are responsible for the poor quality of sleep in CKD patients. Anxiety and depression due to their disease and comorbidities play a part. More importantly, these patients have problems related to their dialysis treatment. Dialysis can interfere with the body’s melatonin production and disturb sleep in other ways.
To study the possible long-term applications of melatonin in kidney disease, researchers gave the drug to 67 CKD patients who were receiving daily hemodialysis. They observed a “beneficial effect on sleep onset latency” (the time it takes to fall asleep) for the first three months of melatonin administration, but then the effects began to wane. It’s not known what was responsible for the diminishing effects.
Cardiovascular benefits of melatonin in CKD patients
In the same paper, the researchers hypothesized that melatonin may improve blood pressure levels in patients with kidney disease. Cardiovascular disease is the most common cause of death among CKD patients, and while the reasons for this are unclear, the researchers propose that reduced melatonin levels may play a role.
Even in healthy individuals, blood pressure drops in the evening and rises in the morning. This is normal, but CKD patients often have an excessive blood pressure spike in the morning hours, and their levels tend to be higher during the day. Even after receiving a kidney transplant, patients still show higher blood pressure levels. It’s thought that some impairment in melatonin production may be the cause, and therefore, melatonin supplements may be part of the solution.
Other studies have shown a similar benefit. A 2019 paper stated that “long-term treatment with melatonin” was associated with vasoprotection and decreased oxidative stress and inflammation in mice. However, it’s not known if the same effects have been established in humans.
Although research on melatonin in kidney disease is still in its early stages, the hormone shows promise in treating multiple facets of the condition. One day, it may be a part of conventional kidney disease treatment.
Written by Natan Rosenfeld