Glance around the waiting room in your family doctor's office, and many people may be facing more than one chronic illness, even if they're only in middle age.

Chronic illnesses - such as high blood pressure, high cholesterol, arthritis, depression, and heart disease -- are not just the province of the elderly. They can surface years earlier, often driven by hazards such as smoking, poor nutrition, and inactivity.

How common are chronic illnesses? In a Canadian study of 980 adults treated by 21 family doctors, nine out of 10 had more than one chronic condition. Nearly half of the middle-aged patients (aged 45-64) had five or more chronic conditions.

So many people have multiple illnesses that doctors would have to work nearly 30 percent more annually to be able to manage them all, says another study. Both reports appear in the Annals of Family Medicine's May/June issue.

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You, Too?

What do those numbers have to do with you? An estimated 57 million Americans had multiple chronic conditions in 2000, and that number is expected to reach 81 million by 2020.

That's according to the Canadian researchers, who included Martin Fortin, MD, MSc, CMFC. Fortin works in the family medicine department at Quebec's Sherbrooke University.

The most common chronic illnesses in Fortin's study were high blood pressure, high cholesterol, and rheumatological diseases. The good news: Those conditions can be treated. Even better, a healthy lifestyle (including a good diet and adequate exercise) can help.

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Fortin's study included 320 men and 660 women. On average, the men were about 58 years old and the women were 55. Multiple chronic illnesses were the rule, not the exception, write the researchers.

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Doctors on Deadline

In the same journal, Duke University researchers totaled the time it would take for primary care doctors to manage America's top 10 chronic illnesses. Those conditions are: high cholesterol, high blood pressure, depression, asthma, diabetes, arthritis, anxiety, osteoporosis, chronic obstructive pulmonary disease, and coronary artery disease.

When stable and under control, those health problems would take up about 3.5 hours of a doctor's day, say the researchers, who included J. Lloyd Michener, MD.

Unfortunately, those conditions are often much more volatile. That bumped up the estimated time commitment to about 10.5 hours per day. That's more than a day's work, and it doesn't count other illnesses, treatment side effects, or patient education.

It may be time to take a fresh look at patient care, say the two studies. "New health care models must be proposed and evaluated if we are to meet the needs of these patients," write Fortin and colleagues.

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By Miranda Hitti, reviewed by Brunilda Nazario, MD

SOURCES: Fortin, M. Annals of Family Medicine, May/June 2005; vol 3: pp 223-228. Ostbye, T. Annals of Family Medicine, May/June 2005; vol 3: pp 209-214.