enlarge Press Herald file/2007

Dr. Usha Nalamalapu, a sleep physician working in Biddeford and Portland, says many factors contribute to problems with sleep.

enlarge Press Herald file/2004

Sensors are placed on the head of a client undergoing sleep tests at the Maine Sleep Institute in Portland.

SLEEP GUIDELINES

EXERCISE REGULARLY, about six hours before you want to sleep.

AVOID napping.

GO TO SLEEP and awake at the same time every day.

SAVE YOUR WORRIES for daytime (If concerns come to mind in bed, write them down in a "worry" book, then close the book until the morning.)

SELECT A RELAXING bedtime ritual, like a hot bath or listening to calming music. Recommendations by the National Sleep Foundation

When she was a college student in the late 1960s, Janice Chapman never worried about sleep.

"I could drink coffee at 9 at night and go to sleep an hour later," she says. "I never thought about caffeine."

For the next 24 or so years after college, Chapman enjoyed healthy restful sleep. That changed when she turned 45.

"My mother had just been diagnosed with cancer when I first noticed the problem," she says. "I'd fall asleep and wake up at 1 in the morning and not be able to get to sleep."

Now 59 and years past the crisis that originally led to worry and sleep loss, Chapman still contends with insomnia and has adjusted her life accordingly. She won't drink coffee or other caffeine-containing drinks after noon. She doesn't use her computer before bedtime, and avoids stimulating TV shows during the evening.

Once and a while she takes a homeopathic pill called Calms Fort before bedtime, or another over-the-counter sleep aid. Walking and cycling also help.

"Most of the time I'm able to sleep pretty well," says Chapman, who nevertheless thinks about sleep issues such as caffeine intake, and guarding against over-reliance on sleep medication.

The sleep problem Chapman describes is so common that, if you look out your window at houses up and down the street, you can be sure that a sleep-deprived person resides in at least two-thirds of them.

That's supported by statistics posted by the National Sleep Foundation, which also holds that older Americans -- which now includes the leading edge of baby boomers -- suffer most from lack of sleep.

"The problem is almost like a layer cake," says Dr. Usha Nalamalapu, a heart specialist and sleep physician who directs The Sleep Laboratory at Southern Maine Medical Center in Biddeford and also serves the Maine Sleep Institute in Portland.

Her layer-cake comparison refers to many things that can impinge on healthy sleep as a person ages. One is prescription medication. Another is that sleep itself tends to be light and fragmented. Restless leg syndrome and sleep apnea, a malady in which a patient stops breathing repeatedly during sleep, are more common among older people.

"The topping of the cake," she says, "is today's culture. There's the impact of caffeine, alcohol, of not being physically active -- and having computers and televisions on. It's not normal, if you think about it."

People over 50 need as much sleep as younger adults and, according to the National Sleep Foundation and sleep experts such as Nalamalapu, sleep deficit of the sort suffered by hundreds of thousands of Americans has consequences.

Every time a light sleeper awakens during the night, explains Nalamalapu, an arousal reaction triggers a surge of adrenaline. Heart rate increases, blood pressure rises, brain patterns change. Repeated night after night, unwanted awakenings make high blood pressure, stroke and heart attack more likely. Sleep deprivation may also lead to carbohydrate craving, which can lead to Type 2 diabetes.

A visit to one's primary care physician, and subsequent lifestyle change are often enough to restore restful sleep.

But not always.

When sleep apnea occurs or -- more alarmingly -- a tendency to drift into sleep while driving, an overnight stay at one of Maine's sleep labs is warranted.

"When that happens," says Nalamalapu, "I jump on board right away and call one of the labs I work with for the first available opening."

In the meantime, she says, the drowsy person should not drive.

"Sleep (deprivation) is a huge element in automobile accidents," she says, "even when an accident is judged to be due to other factors."

Patients usually spend one night in a sleep lab, where polysomnogram reveals dozens of factors that affect a night's rest. Oxygen intake, muscle activity, brain waves, snoring and heart patterns are among things revealed.

"It's quite a challenge...