Sound Familiar??

November 28, 2006

This was in the NY Times Today:

An Epidemic No One Understands

By DENISE GRADY

Published: November 28, 2006

When our first son developed asthma as a 3-year-old, my husband and I

felt pretty much blindsided. We were only a little less shocked when

the same thing happened to our second son, at the same age.

The Asthma Epidemic (NEJM)The disease turned out to be tenacious, and

for years both boys needed inhalers or a nebulizer machine several

times a day to prevent asthma attacks that could keep them up half

the night, coughing and wheezing.

Both had eczema, too, and the kind of food allergies — to nuts,

peanuts and shellfish — that can lead to fatal reactions.

What caused all this? My husband and I were mystified, because

neither of us had asthma or life-threatening allergies, nor did our

parents or siblings. I do have hay fever and allergies to cats and

dogs, but I had always considered my symptoms just a nuisance — not a

bad omen for the next generation. My husband isn't allergic to

anything.

But we seem to have been caught on a rising tide that no one fully

understands. Our sons were born in 1984 and 1987, and we encountered

an awful lot of children their ages who had the same illnesses, far

more than we remembered from our own generation.

Statistics suggest that something strange was occurring in those

years. From 1980 to 2003, the prevalence of asthma in children rose

to 5.8 percent from 3.6 percent, an increase of about 60 percent,

according to the Centers for Disease Control and Prevention.

Other estimates from the disease centers show an even bigger increase

in the asthmas rates for younger children: a 160 percent jump in

those younger than 5 from 1980 to 1994. But changes in data

collection starting in 1997 make it hard to compare the figures

before and after that year. More recently, the rates seem to have

leveled off in the United States and in other Western countries. In

any case, about 20 million people in the United States have asthma

today, including at least 6 million children, and 5,000 people a year

die from it. Children in the inner cities seem to be especially hard

hit, with exposure to cockroaches and diesel fumes suspected as the

culprits. But the cause is not known for sure.

Worldwide, the disease has also increased. From 1985 to 2001, the

prevalence rose 100 percent. About 300 million people have asthma,

255,000 die from it, and deaths could increase by 20 percent over the

next 10 years, according to the World Health Organization. The

problem is especially severe in developing countries, which are least

able to provide the long-term intensive treatment that asthma

requires.

Some of the apparent increases may not be real, but may have occurred

because doctors got better at making the diagnosis. But increased

reporting seems unlikely to account for all the new cases. Theories

come and go, and when you come right down to it, no one really knows

why some people develop asthma and others don't.

In " The Asthma Epidemic, " an article published last week in The New

England Journal of Medicine, doctors tried to sort out various

theories about the causes of asthma and explain why rates have risen.

But there are no clear-cut answers.

Like other chronic diseases, asthma is probably caused by multiple

genes and environmental exposures, and it can have quite different

causes in different people. About half the cases are thought to stem

from allergies and the rest from other problems that can irritate and

inflame the airways, causing them to close.

Genetic changes in the population cannot explain the increasing

rates, though, because such changes occur too slowly to account for

the rapid increases in asthma, the authors said, suggesting that

environmental factors are more likely candidates. But what has

changed enough in the environment to explain spiking asthma rates?

The authors of the article, from University Children's Hospital in

Munich, review many study findings. They report that one clear risk

factor is secondhand tobacco smoke. Exposure to it does increase

asthma risk in infants and small children. But how would that explain

the increases, when over all, parents today smoke less than previous

generations?

People frequently blame air pollution for causing asthma, but its

role is not entirely clear. Pollution does makes asthma worse in

people who already have the disease, but it's not known whether

pollution also makes asthma develop in the first place. And in any

case, air pollution in the United States has decreased in the last

few decades. Living in a place with high vehicle exhaust may make

asthma worse, but the evidence is " relatively weak, " the researchers

report.

Dust mites, microscopic insects that live in bedding and furniture,

were long blamed for causing asthma to develop in infants and small

children and have led to a booming industry of mattress covers, air

filters and guilt-ridden parents tethered to dust mops and vacuum

cleaners. But recent studies have questioned the connection. Once

children have asthma, though, the mites and their droppings may make

the symptoms worse.

Cat dander has become a complete puzzle, with some studies finding

that exposure early in life leads to asthma, and others saying it

protects against asthma. At this point, nobody knows which study to

believe, but most experts agree that when people already have asthma,

being around cats can make it worse.

Cat dander has become a complete puzzle, with some studies finding

that exposure early in life leads to asthma, and others saying it

protects against asthma. At this point, nobody knows which study to

believe, but most experts agree that when people already have asthma,

being around cats can make it worse.

The Asthma Epidemic (NEJM)Under some of the theories, I should have

had the world's worst asthma. Clearly, I had allergic tendencies, and

the experts would have shuddered at my environment. I grew up in New

York in a small apartment with parents who were heavy smokers, on a

busy street with trucks rumbling by and a bus stop in front of the

door. Buildings all around us burned coal. At times, we had a dog, a

cat, parakeets and, briefly, a duck. It's amazing that the pets

survived the smoke. My mother was a decent housekeeper, but she

wouldn't have won any prizes. I never wheezed. Go figure.

Obesity and asthma have also been linked in some studies, but the

link, if it exists, is not understood. Researchers say it is simply

not a matter of asthmatic children growing fat because they cannot

exercise. The weight gain can be first.

Nutrition is another mystery. Studies of fruits, vegetables, cereals,

fatty acids, vitamins, minerals and antioxidants have been

inconclusive, and little is known about the effects from what

pregnant women eat. Experiments in which pregnant women avoided cow's

milk and eggs in hopes of preventing asthma in their infants did not

work, and breast-feeding doesn't prevent the disease, either.

One theory that has received attention recently is the " hygiene

hypothesis, " the idea that children today are raised in homes that

are too clean and that asthma is somehow caused by the lack of

exposure to infections and bits of microbes early in life. Under this

theory, germs are supposed to help the immune system develop

normally, and without them the system may overreact to other

substances in the environment, producing allergies and asthma.

There is some evidence to support the idea. Studies find that

children raised on farms are less prone than others to asthma, maybe

because they are exposed to plenty of microbes in barns and stables.

But the connection is still not fully understood, and some viral

infections clearly make asthma worse.

A related idea is that the increased use of antibiotics in recent

decades contributes to asthma by changing the type of the bacteria

that live in the gut. But that has not been proved. Some researchers

have suggested that acetaminophen, used to treat pain and fever, may

be linked to asthma. Its use increased in the 1980s, after

pediatricians declared aspirin unsafe for children. But that theory

has not been proved, either.

Ultimately, this new list of the usual suspects still doesn't solve

the mystery.

Gradually, my sons' asthma diminished. Both became track and cross-

country runners in high school, and now, as they have gone on to

college and graduate school, the disease is rarely a problem. But it

was a worry that hung over us for a long time.

As for the food allergies, we choose to assume that they last for

life. The only way to find out for sure is called a " challenge, " in

which you eat the risky food with doctors standing by to revive you

in case it turns out that, gee, you're still allergic to it after

all. Somehow, I don't think we'll be signing up for that.

My sons have adrenaline kits to treat a severe reaction. Neither has

ever needed it, and I know they don't carry it around the way they're

supposed to when they go to restaurants.

Needless to say, I wish none of this had ever happened. But, based on

what's now known, could I have done anything to prevent it? Was it

bad that we had cats when our children were born or that we later

gave them away? Asthma transformed me and my husband from rather

casual housekeepers into mop-wielding fanatics. I'm not sure it

helped.

Suppose I had recognized that my own allergies meant that my children

would be at risk. Would it have helped if I had then avoided eating

nuts, peanuts and shellfish while I was pregnant and breast-feeding?

I don't think the answer is clear.

Similarly, I'm not convinced that it would have made a difference if

I had been more cautious and methodical about introducing new foods

in their first few years, though allergy groups recommend it. The

only thing that seemed to do them any good was asthma medicine, and

lots of it.

Because children who have even one parent with allergies and asthma

have an increased risk of developing the same problems, it would be

great if somebody could figure out a way to lower that risk in time

to help my sons and the millions of other young people who were also

caught in the asthma wave, when they decide to become parents. I am

hoping, but I know it may be a problem with many solutions — or none.

(NEJM)Under some of the theories, I should have had the world's worst

asthma. Clearly, I had allergic tendencies, and the experts would

have shuddered at my environment. I grew up in New York in a small

apartment with parents who were heavy smokers, on a busy street with

trucks rumbling by and a bus stop in front of the door. Buildings all

around us burned coal. At times, we had a dog, a cat, parakeets and,

briefly, a duck. It's amazing that the pets survived the smoke. My

mother was a decent housekeeper, but she wouldn't have won any

prizes. I never wheezed. Go figure.