Extreme long and short sleepers develop pulmonary fibrosis more quickly

Long and short sleep times increase the risk of lung fibrosis

People who sleep more than eleven or less than four hours on a regular basis are two to three times more likely to develop incurable pulmonary fibrosis than people who sleep an average of seven hours a day. This emerges from an English research work.

University of Manchester researchers have found that extreme sleep times are associated with a higher risk of developing lung fibrosis. A circadian rhythm ("inner clock") that is out of rhythm is assumed to be the cause of this connection. The results were recently published in the technical journal "PNAS".

Pulmonary fibrosis - unknown and often fatal

Over 100 different lung diseases are summarized under the term pulmonary fibrosis. All forms are characterized by chronic inflammation of the lung connective tissue, whereby the fine walls of the alveoli are particularly affected. The inflamed lung tissue is converted into connective tissue - the lungs scarred and hardened increasingly. As a result, oxygen is less able to get into the blood vessels and breathing in is progressively more difficult.

Since many different, sometimes very rare, forms are grouped under pulmonary fibrosis, there are no clear figures on their distribution. It is estimated that around 15,000 people in Germany suffer from pulmonary fibrosis. A cure does not exist because altered lung tissue cannot be converted back into functional tissue. It is therefore a very serious illness that in many cases leads to death.

Each cell is based on an internal clock

The Nobel Prize-winning discovery of the circadian rhythm revealed that all cells in the body follow a natural internal clock. The rhythm is regulated by certain hormone releases, which are based on sunlight. The internal clock thus adapts to the natural change between day and night.

A healthy sleep reduces the risk

In experiments on mice, the researchers discovered that fibrotic processes in the lungs are triggered when the circadian rhythm of the lung cells is disturbed. This finding was checked on human data from the British biobank. It was clearly shown that both short and long sleep times are associated with a greatly increased risk of pulmonary fibrosis.

Long sleep is even more risky than short one

According to the analysis, regular sleep times of four hours or less are associated with a doubled risk of fibrosis. People who regularly sleep eleven hours or more are three times more likely to be at risk. The control group was people who regularly sleep seven hours. Lower, but still increased, risks were also observed in people who stay up late at night or do shift work.

New therapeutic approaches

"Lung fibrosis is a devastating disease that is currently incurable," explains research director Dr. John Blaikley. The discovery that the body watch may play a key role opens up new approaches to treating or preventing the disease.

Does an unnatural rhythm make us sick?

"It is fascinating that the internal clock activity is increased in the case of fibrotic diseases," adds Dr. Peter Cunningham, one of the study authors. Previous studies had already shown that the body clock also plays an important role in infectious diseases, cancer and diabetes. (vb)

Author and source information

This text corresponds to the requirements of the medical literature, medical guidelines and current studies and has been checked by medical doctors.

Graduate editor (FH) Volker Blasek


  • Peter S. Cunningham, Peter Meijer, Alicja Nazgiewicz, and others: The circadian clock protein REVERBĪ± inhibits pulmonary fibrosis development, PNAS. 2019,

Video: An Innovative Solution to Curing Pulmonary Fibrosis (January 2022).