Timing it right - how does your body clock affect your asthma?

I’ve always been interested in how the time of day affects asthma symptoms. At medical school, we’re taught asthma is very, very rhythmic. We're taught to look at the peak flow charts when patients come into hospital and how their peak flows drop. Then you don't release them out of the hospital until their peak flows come back up again. And that changes on a daily basis. But we never really understood why that happened.

I always knew the time of day was important

When I was a junior doctor doing night shifts, everything would be quiet around midnight. Then at 4am, guaranteed, the doors to A&E or Resus would open and people would come in with asthma attacks. It happened pretty much every night, so I knew there was something odd about that time of day.

There's something definite about the way people with asthma’s body clocks work that's different from people who don't have asthma. Every time we seem to look at anything to do with asthma, it does come back to being rhythmic. 

Listening to the body’s internal clock

And it seems that you can pick up these rhythmic signals fairly easily in patients. And these aren't patients who are going through circadian experiments, these are just patients have come from their homes to spend a night in hospital. And basically, you find that it is the internal clock – not the external environment like the light, for example - that controls the narrowing of their airways, which is what can trigger asthma symptoms.

Finding the natural rhythm

My latest research shows that asthma symptoms follow the body’s natural clock, pointing to time-based treatments and diagnosis as a new way to improve care. It shows that some indicators used to assess inflammation in asthma are significantly higher in the morning than in the afternoon. So, testing in the morning could potentially improve diagnostic accuracy. It also means that people could go on to get treatment without having to wait to get other tests done. My body clock research has also found that the time of day that people use their brown inhaler makes a difference. We found that treating asthma at 4pm seems to be more effective than at other times of day.

Research has a real-life impact on people

The Asthma + Lung UK Career Development Award was my first big independent grant. Research is expensive and it’s only due to that award that I was able to start my respiratory research studies. And my research is having a real-life impact on people living with asthma. Following my research, new European guidelines on managing and preventing asthma now include recommendations about the importance of timing in the diagnosis of asthma. I'm now seeking funding for two major follow up studies. One would further investigate how the time of day affects diagnostics and testing. The other would evaluate the effect of the body clock on modern combination inhalers used in AIR and MART approaches.

Research will help us do so much better

Both studies have the potential to generate powerful new insights that could improve diagnosis and treatment for people living with asthma.

We don’t have all the answers yet, but it would be fantastic if, through research, we could find out what time of day asthma treatment is likely to give the greatest benefit to patients. I do feel we should be able to treat asthma for people so that they have a normal, healthy life. We could do so much better, and research will help us do it.