For the past six years, the nonprofit Asthma and Allergy Foundation (AAFA) has released a list of the "Asthma Capitals" -- the worst cities for asthma. The top offenders for 2009: St. Louis, Milwaukee, and Birmingham, Ala.
But if those are the worst cities for asthma sufferers, does that mean other cities are relatively good for people with asthma -- or at least benign?
The AAFA doesn't rank the "best" cities for asthma, nor does any other medical or advocacy organization. But there are a number of factors that can make a city relatively good -- or bad -- for people with asthma. From geography to climate to pollen count, here's what you need to know about cities that are better for people with asthma.
'Best' Cities for Asthma?
When researchers at the AAFA rank cities for the Asthma Capitals survey, they look at the top 100 largest metropolitan areas and evaluate them on a number of criteria, including asthma prevalence, pollution levels, and pollen counts. The ten cities that ranked best in the AAFA survey are:
- Cape Coral, Fla.
- Colorado Springs, Colo.
- Portland, Ore.
- Palm Bay, Fla.
- Daytona Beach, Fla.
- San Francisco,
- Portland, Maine
- Boise City, Idaho
But are these the "best" cities for asthma in the U.S.? No, says Angel Waldron, Marketing and Communications Manager for the AAFA, who worked on the survey.
"We get so many people with asthma asking us, 'Where should I move?'" Waldron tells WebMD. "Unfortunately, it's just not a question we can answer. There are so many factors, and it all depends on what triggers your symptoms." A city that might be good for one person's asthma might be terrible for yours.
Still, while there's no such thing as a best city for asthma, experts say that certain factors in cities can influence a given person's asthma -- for better or worse. Here's the rundown.
Geography. Asthma experts say that geography can play a role in a person's asthma symptoms. Many of the cities that ranked well on the AAFA's survey were on the water. For instance, three of the ten better cities for asthma were on the coast in Florida.
"If you're living on the water, the wind can blow away a lot of the potential allergens and irritants," says Jonathan A. Bernstein, MD, an allergist at the University of Cincinnati College of Medicine.
Pollen counts also tend to be lower in areas on the water, says Cascya Charlot, MD, medical director of Allergy and Asthma Care of Brooklyn.
On the other hand, cities that don't get a lot of air circulation -- for instance, those located in valleys -- can be tough for people with asthma. "Valleys can sometimes trap pollutants," says Bernstein. "The air doesn't move as freely."
Still, while breezes from oceans and lakes may have a benefit, being on water is no guarantee for good air quality. "Other cities on the water like Milwaukee didn't score very well," says Waldron.
Weather Conditions. Many cities that ranked well for people with asthma have fairly mild climates, like San Francisco and Seattle. Asthma experts say that extreme temperatures are a common nonallergic asthma trigger.
"When the air gets really cold, it can almost shock the lungs and cause a bronchospasm that narrows the airways," says Bernstein. Shifts in barometric pressure are another common asthma trigger, he says.
That said, the potential benefit of living in a mild climate depends entirely on your asthma triggers. Some people with asthma do well when they move away from the cold winters of Minnesota to hot, arid climate of Arizona. For others, it doesn't make much of a difference.
While some coastal towns ranked well on the AAFA's list of asthma cities, their humidity could be a problem for many people with asthma. Humidity is an irritant that can trigger asthma symptoms. Also, humid environments encourage allergens like mold and dust mites.
"Cape Coral, Fla. ranked [best] on our Asthma Capitals list this year," says Waldron. "But if mold is a trigger for you, it might not be so great."
Pollen Count. Pollens are among the most common allergic triggers for people with asthma. The types of pollen and the season vary from region to region.
"In the spring, some of the toughest cities are in the southeast, because that's when tree pollen from oak, maple, and elm is worst," says Waldron. "Then in the fall, the ragweed in the northeastern cities becomes a real problem."
Of course, it all depends on the type of pollen. If you live in an area with a high pollen count but aren't allergic to those particular pollens, you won't have a problem.
Pollution. "It's no surprise to anyone that cities have a lot of pollution," says Charlot. "In a city, you've got more cars on the road, more businesses, and more factories putting pollutants into the air." Since pollutants themselves can be irritants, they can have a big effect on a person's asthma symptoms.
What you might not realize is that pollution levels can also indirectly increase pollen levels. How? Carbon dioxide is a waste product produced by combustion; it's also a gas that plants need to grow.
"Studies have shown that in urban areas with a lot of pollution, the high carbon dioxide levels encourage plant growth," says Bernstein. "That increases the pollen levels."
Other Allergens. Keep in mind that cities in general are likely to have pests -- like cockroaches, mice, and rats -- all of which can trigger allergies and asthma attacks. They're often most problematic in poorer urban neighborhoods.
Smoking Ordinances. When evaluating a particular city's effect on asthma, it's not only about pollen counts and weather. Charlot says that smoking laws -- banning smoking in workplaces and restaurants, for instance -- may be having a real impact on asthma symptoms.
"Some studies have found that in cities that enact smoking legislation, there's a decrease in ER visits for asthma emergencies," Charlot tells WebMD.
Asthma and Cities: Should I Move?
Understandably, many people living in cities and suffering with asthma are desperate to get out. They want to move, convinced that life in another part of the country will resolve their asthma symptoms. However, asthma experts generally advise against the idea.
Why? For one, it often doesn't work. Asthma is such a complex disease -- affected by so many different factors -- that it's hard to predict how a person will do in a new location, Waldron says.
Another thing to keep in mind: people who have allergies are prone to developing new allergies. So after all the bother of moving, you could just wind up trading your old ragweed allergy in Boston for a brand new oak tree allergy in Palm Bay, Fla.
Be very cautious when considering a move because of your asthma symptoms. Remember, there's no best city for asthma. If you're determined, Bernstein recommends that you try living in the new location for a few months before permanently uprooting yourself.
Controlling Your Asthma Symptoms
Of course, you could be living in one of the "best" cities for asthma and still have the nation's worst asthma symptoms. Location matters less than how well you're controlling your condition, experts say.
Start at home. Even if you have no power over the weather, smog, or the pollen count outside your house, you do have some control over the allergens and irritants inside it. And what's inside might have a bigger impact on your asthma symptoms.
"People spend an average of 22 hours a day indoors," says Bernstein. That makes for a lot of exposure to potential asthma triggers in a confined space. Allergy-proofing your home and removing irritants -- like perfumes and cleaning agents -- could really help.
You also need to work with your doctor to get control of your condition. If you have allergic asthma, that means allergy testing. It's the only way to find out precisely what is causing your problems. You'll also need to use your medications exactly as prescribed.
While it's good to be aware of how the local conditions in your city could affect asthma symptoms, where you live shouldn't dictate how you feel.
"As long as you have good control of your asthma, you really can live in any city in the world and still be symptom-free," says Waldron.