British researchers said they detected lower levels of protective molecules in blood in the morning.
This could be increasing risk of blood clots and heart attacks at those times. The discovery could lead to new ways to diagnose, treat and prevent cardiovascular disease.
The body's clock is set in part by environmental cues including the light-dark cycle and by the control of body functions, including sleep, heart rhythm and feeding. Researchers found that in patients with heart disease, the activation of blood cells in the early hours of the morning is associated with an increased incidence of blood clots, heart attacks and strokes at those times.
The new study conducted by a team of researchers led by Dr. Jesmond Dalli from Queen Mary's William Harvey Research Institute found that a group of important molecules that were recently discovered, controls the activity of blood cells, and that patients with heart diseases have low levels of these molecules.
In the study, which was published in the journal Circulation Research, Dalli said: “For people with heart disease, in the morning just before getting out of bed, an increase in heart rate together with other changes in the blood stream, results in an activation of cells in the blood stream. This leads to the formation of small clots which may lead to blockage of the blood vessels resulting in heart attack or stroke.”
"We were surprised to discover that a small group of molecules from an essential fatty acid, previously thought not to have any importance, actually appears to control this vital cell activation process,” he added.
The scientists looked at a group of recently discovered molecules, which are produced from omega-3 fatty acids, the same fatty acids found in fish oils. These molecule are involved in controlling both white blood cell and platelet behavior during inflammation, allowing the body to heal itself.
The team collected blood from seven healthy volunteers and 16 patients with cardiovascular disease. In healthy people, they found that the molecule level increased during the early morning hours and helped keep in check the behavior of both white blood cells and platelets. In patients with cardiovascular disease, however, the production of these molecules was significantly low, which increases the formation of blood clots.
