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sicknesswhy do people feel worse at night? Body clock set for suffering in p.m.

August 19, 2007 12:35 am

BY REBECCA BLATT

For many, they are familiar scenarios.

Your daughter makes it through the day with a mild earache, only to cry out in pain at bedtime.

Your allergies are bearable in the morning and afternoon, but your sinuses seem to close up when you crawl into bed at night.

You don't notice your acid reflux until you begin to drift off to sleep, when heartburn radiates from your core.

The list of symptoms that can get worse at night goes on and on.

But why? Do we just notice these symptoms more when we're tired?

Fredericksburg infectious-disease doctor Paul Fiore said yes--some symptoms feel worse at night because that's when we have the fewest distractions.

"Distraction is kind of a major way we deal with pain," he said.

But Fiore and other physicians said that the body's circadian rhythms--cyclical changes that occur during each 24-hour period--trigger nighttime responses as well.

The discomfort we feel at night isn't just in our minds, it's in our hormones, our airways and our stomachs, too.

Fluctuations in lung function and hormone levels may account for why asthma patients report that their symptoms worsen at night, said allergist Dr. Seth Craig of Allergy and Asthma Center of Fredericksburg.

He explained that even for those without asthma, lungs tend to work best in the morning and worst around 3 or 4 a.m.

Craig suggested that the change may be due to a natural dip in a hormone called cortisol, which helps keep airways open and asthma under control.

"That is one possible reason why people with asthma may have worsening at night," he said. "They don't have as much of their own protective hormone."

But doctors also suggested a simpler explanation for nighttime breathing problems: posture.

Our chest walls weigh on our lungs when we lie down, said Dr. Nariman Dash, a Fredericksburg ear, nose and throat specialist.

That can make it more difficult to breathe and clear mucus from airways--which may leave asthmatics gasping for air.

Changing hormone levels can cause allergies to worsen at night as well, said Richard Fiero, a Fredericksburg pulmonologist and sleep specialist.

He said that while the level of protective hormone cortisol is lowest at night, the level of a chemical called histamine, which causes allergic responses including constricted airways, is, conversely, highest at night.

"If it's a struggle between those two, the histamine is going to win out in the middle of the night," Fiero explained.

He also said that conditions outside the body might cause allergy symptoms to worsen at night. For instance, pets might leave fur on pillows and bed linen during the day, which may make you sneeze at night.

Cleaning linens and dusting regularly, as well as using allergen-free pillow covers, could help in that case. Of course, standing up in the morning could help, too.

Horizontal posture is also to blame for exacerbated acid reflux, said gastroenterologist Waring Trible Jr.

"It's because we lie down at night--that's the bottom line," he said.

Trible explained that gravity helps prevent stomach acid from making its way up the intestinal tract while the body is upright, but people with acid reflux may not be able to prevent acid from washing up the esophagus while lying down.

In addition, Trible pointed out that Americans tend to eat heavy meals at night, which causes the body to secrete more acid in the evening. For people with acid reflux, that means symptoms may worsen after dinner.

While eating lighter meals at night may help prevent the problem, Trible said it is difficult for patients to change lifelong habits, especially when family and friends may eat larger dinners as well.

Instead, Trible recommended that patients with acid reflux take medication to prevent pain and long-term damage to the esophagus.

Ayanna McCray, a King George pediatrician, said that adults aren't the only ones who complain of nighttime discomfort.

She said the children she sees complain of several additional conditions that get worse at night.

Ear infections are among them. McCray said that lying down can lead to a build-up of pressure behind the eardrum, which may make pain worse.

She said that teething pain tends to get worse at night, though she is not sure why, and she also said that coughs can get worse at night.

McCray speculated that lying down might also play a role in that phenomenon.

"It may just be that when you're lying down the airways collapse a little bit anyway," she said.

Fiore added that sleeping with your mouth open may make sore throats more uncomfortable because the body cannot keep the throat as moist as it does during the day. He said that gargling with salt water may help soothe a dry, sore throat.

As if the body's internal clock didn't cause enough trouble during nighttime hours, it turns out that our daily rhythms pose dangers in the morning as well.

In particular, heart attacks are twice as likely to occur in the morning than at any other time, said Dr. Jeffrey Askew, a Fredericksburg cardiologist.

Askew said there are many reasons for the difference--these include eating fatty breakfasts and smoking on the way to work.

But Askew said that the risk may be due, in large part, to the stress hormones released in the morning.

He explained that the body secretes adrenalin to raise blood sugar levels, increase the heart rate and stimulate the brain in preparation for the day ahead.

But the adrenalin rush can also lead to a higher risk of heart attacks, Askew said.

So if we avoided falling asleep and waking up altogether, would we feel better as a result?

Insomniacs will tell you--definitely not.

Our biological clocks are likely set to get a good night's rest for a reason. So until we find a way to sleep standing up, nighttime earaches, stuffy noses and morning stress are just risks we'll have to take.