It is well-known that severe weather can aggravate asthma symptoms. But when most people think severe weather, they are probably thinking about extreme cold or extreme heat / humidity. I know these are the weather conditions I notice affect my asthma symptoms most often.

However, a new study reveals that thunderstorms may be another type of severe weather asthma trigger. Here are the highlights:

• Study was carried out in Atlanta, Georgia, an area known for its frequent and severe storms
• Data was collected on emergency room visits over 12 years (1993 to 2004) for 41 of 42 hospitals in Atlanta
• Thunderstorm data was collected from a weather station at the Atlanta airport for the same time period
• Comparison of the data showed a 3% spike in ER visits for asthma the day following a thunderstorm

However, despite these findings, researchers also noted that the effect varied with other weather phenomenon that accompanied the thunderstorm. For example, if no rain fell, then there was little effect on asthma flares. But rainfall of as little as 1/10th of an inch had a significant effect on asthma ER visits. Winds also had an effect.

Researchers aren’t clear yet on why thunderstorms have a negative effect on asthma. But one theory is that pollen grains are broken up by osmotic shock in the rain water that occurs with some storms. And that releases allergens, which are in turn spread by the strong winds of the thunderstorm. What a combination!

Researchers do stress, though, that study data was for the Atlanta area only and results might differ in other geographical areas. Clearly, more study will be needed to further validate the findings. Still, I find these results to be compelling.

My advice? Stay inside during and after the next thunderstorm… for your health’s sake!