Dr. Ron’s Research Review – April 1, 2020

©

This week’s research review focuses on dim light melatonin onset and CFS.

Dim Light Melatonin Onset

Melatonin may be an effective treatment for patients with chronic fatigue syndrome and late dim light melatonin onset. (van Heukelom et al., 2006)
Melatonin secretion under dim light conditions (the dim light melatonin onset or DLMO) is the single most accurate marker for assessing the circadian pacemaker. In this test, melatonin is measured after one hour in dim light. (Pandi-Perumal et al., 2007)

Chronic Fatigue Syndrome

A study publishd in the European Journal of Neurology explored the effect of melatonin, a chronobiotic drug, in 29 patients with chronic fatigue syndrome (CFS) and Dim Light Melatonin onset (DLMO) later than 21.30 hours, reflective of delayed circadian rhythmicity. The Department of Neurology, Sleep-Wake Disorders and Chronobiology, Hospital De Gelderse Vallei, Ede, and Department of Medical Psychology, Radbound University Medical Centre, Nijmegen, The Netherlands conducted the study.
The patients took 5 mg of melatonin orally, 5 h before DLMO during 3 months. Their responses to the checklist individual strength (CIS), a reliable questionnaire measuring the severity of personally experienced fatigue, were assessed twice with a 6-week interval immediately before the treatment and once after 3 months treatment. In the pre-treatment period the fatigue sub-score improved significantly.
After treatment, the total CIS score and the sub-scores for fatigue, concentration, motivation and activity improved significantly. The sub-score fatigue normalized in two of the 29 patients in the pre-treatment period and in eight of 27 patients during treatment. This change was significant. In the patients with DLMO later than 22.00 hours (n=21) the total CIS score and the sub-scores for fatigue, concentration and activity improved significantly more than in the patients (n=8) with DLMO earlier than 22.00 hours.
Melatonin may be an effective treatment for patients with CFS and late DLMO, especially in those with DLMO later than 22.00 hours. (van Heukelom et al., 2006)

Dr. Ron

 


Articles

 

Dim light melatonin onset (DLMO): a tool for the analysis of circadian phase in human sleep and chronobiological disorders.
            (Pandi-Perumal et al., 2007)  Download
The circadian rhythm of melatonin in saliva or plasma, or of the melatonin metabolite 6-sulphatoxymelatonin (aMT6S) in urine, is a defining feature of suprachiasmatic nucleus (SCN) function, the endogenous oscillatory pacemaker. A substantial number of studies have shown that, within this rhythmic profile, the onset of melatonin secretion under dim light conditions (the dim light melatonin onset or DLMO) is the single most accurate marker for assessing the circadian pacemaker. Additionally, melatonin onset has been used clinically to evaluate problems related to the onset or offset of sleep. DLMO is useful for determining whether an individual is entrained (synchronized) to a 24-h light/dark (LD) cycle or is in a free-running state. DLMO is also useful for assessing phase delays or advances of rhythms in entrained individuals. Additionally, it has become an important tool for psychiatric diagnosis, its use being recommended for phase typing in patients suffering from sleep and mood disorders. More recently, DLMO has also been used to assess the chronobiological features of seasonal affective disorder (SAD). DLMO marker is also useful for identifying optimal application times for therapies such as bright light or exogenous melatonin treatment.

Influence of melatonin on fatigue severity in patients with chronic fatigue syndrome and late melatonin secretion.
            (van Heukelom et al., 2006)  Download
The effect of melatonin, a chronobiotic drug, was explored in 29 patients with chronic fatigue syndrome (CFS) and Dim Light Melatonin onset (DLMO) later than 21.30 hours, reflective of delayed circadian rhythmicity. The patients took 5 mg of melatonin orally, 5 h before DLMO during 3 months. Their responses to the checklist individual strength (CIS), a reliable questionnaire measuring the severity of personally experienced fatigue, were assessed twice with a 6-week interval immediately before the treatment and once after 3 months treatment. In the pre-treatment period the fatigue sub-score improved significantly. After treatment, the total CIS score and the sub-scores for fatigue, concentration, motivation and activity improved significantly. The sub-score fatigue normalized in two of the 29 patients in the pre-treatment period and in eight of 27 patients during treatment. This change was significant. In the patients with DLMO later than 22.00 hours (n=21) the total CIS score and the sub-scores for fatigue, concentration and activity improved significantly more than in the patients (n=8) with DLMO earlier than 22.00 hours. Melatonin may be an effective treatment for patients with CFS and late DLMO, especially in those with DLMO later than 22.00 hours.

 

References

Pandi-Perumal, SR, et al. (2007), ‘Dim light melatonin onset (DLMO): a tool for the analysis of circadian phase in human sleep and chronobiological disorders.’, Prog Neuropsychopharmacol Biol Psychiatry, 31 (1), 1-11. PubMed: 16884842
van Heukelom, RO, et al. (2006), ‘Influence of melatonin on fatigue severity in patients with chronic fatigue syndrome and late melatonin secretion.’, Eur J Neurol, 13 (1), 55-60. PubMed: 16420393