The human body clock could have a significant impact on the way doctors are able to diagnose and treat asthma, according to new research.

The study found that the sputum of asthmatics were more than twice as likely to have more inflammatory cells -- or eosinophils -- in morning clinics than in the afternoon. Levels of eosinophils -- a biomarker in sputum -- are used to guide treatment in severe asthma patients. Doctor and patients have long known that asthma symptoms are at their worst in the small hours of the morning.

But previous research has shown that the worsening symptoms are biological in cause, rather than a result of lying down. "These research results are really exciting but at an early stage - our aim was to understand a bit more about how the body clock affects the biochemistry of a person with asthma," said lead author Hannah Durrington from The University of Manchester in the Britain.

"But we are pleased because our work should help with the accurate diagnosis and treatment of asthma in the future. We feel it may also have important implications on other lung conditions, as well as outside respiratory medicine," she added.

According to her, the same way that measuring glucose levels in diabetes allows adjustment of insulin dosing, asthmatics can monitor their biomarker chemicals during the day, to help inform optimum treatment times. The study, published in the American Journal of Respiratory and Critical Care Medicine, examined sputum samples of over 300 severe asthmatics.

Durrington said: "Based on our results, different clinical decisions could be made depending on whether the patient is allocated a morning or afternoon appointment. "And it also points towards opportunities for more personalised treatment for asthma care in the future."