Does weather and in particular heat or barometric pressure have any role in causing attacks of HAE?
Jun 24, 2015
Dr. C:First of all for those who qualify Happy Father’s Day. I would like to thank Lois Perry of the HAEA for providing this question. As is often the case I’m afraid that we don’t have a precise answer. This topic has come up frequently however on patient surveys. We have included questions about weather or barometric pressure in our registry to get a better idea of their importance. This gives me an opportunity to urge you all to participate in the registry—we do hope that it will lead to better answers down the road. Marc and Bruce what thoughts do you have for our readers?
This is an interesting question that often comes up in the clinic: do weather patterns trigger HAE attacks? Certainly a number of patients have told me they suspect this to be true in their own lives. Typically, extremely hot or cold weather, or rapid changes in barometric pressure are the events patients suspect play a role in exacerbating HAE. This is a difficult question to study rigorously in large numbers due to the great variability in regional weather patterns as well as variable individual patient symptoms. One large European center surveyed nearly 100 patients who reported that 15-20% of their overall attacks were suspected to be triggered by weather. When the researchers actually tracked individual patients, HAE symptoms occurred with these specific weather exposure only about 20% of the time, meaning that 80% of the time severe or dynamic weather did not result in an HAE attack. So weather patterns certainly may be an exacerbating factor in some people, but not a very reliable or predictable one in most cases. HAE triggers continue to be a mystery at some level and an area for continued research.
A better way to address this question might be to study the impact of weather changes on a sensitive biomarker for contact system activation rather than attacks. While probably not directly related to this question, it is interesting to note that changes in temperature can provoke hives in certain inducible urticaria patients and that environmental temperature impacts the levels of tissue kallikrein.
Thank you, we are again left with more questions. There is much to be done. We look forward to your input, and will be back next ‘question of the week’.