News

Day or night person: Individual biorhythm can be measured using a blood test


Blood test allows reading the internal clock

Our internal clock determines the individual biological rhythm and has a far-reaching influence on the body functions. With a new blood test, scientists can now objectively determine the status of a patient's internal clock for the first time. This could also lead to improved therapeutic success, for example because the time of taking the medication can be adjusted accordingly.

The individual biological rhythm causes daily fluctuations in the various bodily functions, which can also have an impact on the success of therapeutic measures. So far, however, it has not been possible to determine the patient's internal clock objectively. The new blood test can help here. The international research team led by Professor Dr. Achim Kramer from the Charité Institute of Medical Immunology has identified certain biomarkers in the blood that enable the reading of the internal clock. Their results were published in the specialist journal "The Journal of Clinical Investigation".

Daily fluctuations in body functions

The distinction between lark and owl people describes the difference between people who are active early in the day and go to bed earlier and people who are more of a late riser and therefore stay awake in the evening or at night. This is controlled by our internal clock. It causes individual daily fluctuations in the functions of the human body. As a result, “drugs, for example, have different effects depending on the internal clock - depending on the time at which they are taken,” explain the Charité experts.

Different effects of the medication

The effects of the medication can vary from person to person, depending on whether his internal clock tends to be late or early, i.e. whether the person is more of an owl or a lark, the researchers report. An exact determination of the individual biological rhythm would therefore have great advantages for the therapy. With the help of so-called chronotherapy, drugs can be used more effectively and more tolerably than before, the experts explain.

Biomarkers show the status of the biorhythm

The international research team headed by Prof. Dr. As part of the current study, Kramer initially determined the activity of all 20,000 genes of a certain group of blood cells in several test subjects throughout the day, according to the Berlin Charité. Using special computer algorithms, they were able to determine twelve genes from these data sets that reliably indicate the inside time. They identified biomarkers in the blood that are characteristic of the individual's inner time. The biomarkers of a single blood sample can still distinguish a late type from an early type if the person in question is woken by an alarm clock early in the morning contrary to their biological rhythm, reports the Charité.

Chronotherapy has rarely been used

So far, chronotherapy has rarely been used considering the time of day due to a lack of diagnosis of indoor time, reports Prof. Kramer. However, the expert was convinced that chronotherapy is often superior to conventional therapy. "We think that this first objective test of the indoor time will help to make the time of day much more important for therapy and diagnosis," emphasizes the study leader.

Treatment optimization

In subsequent clinical studies, the scientists are now planning to review the effectiveness of personalized chronotherapy. For this purpose, the therapy is tailored to the patient's individual inner time, the experts explain. If the time window in which an active ingredient is particularly effective is known, the effectiveness of the treatment can be optimized and, at the same time, the risk of side effects reduced, the researchers further. (fp)

Author and source information


Video: PL-PS04 The importance of circadian rhythm for athletic performance and skeletal muscle health (August 2020).