For some, it is aggravating. For others, it is unbearable. For millions of Canadians, it is not hard to imagine at all. To varying degrees, they live with it every day.

Chronic pain is said to be costing society more than cancer, heart disease and HIV combined. That's health care costs, lost productivity and disability.

There are few studies reporting the cost of chronic pain, but the Chronic Pain Association of Canada estimates the cost of chronic pain to the Canadian economy is $10 billion per year.

A study published in the Journal of the American Medical Association in November 2003 reported chronic pain cost $62 billion in reduced performance each year in the U.S. That climbed to $100 billion when lost time and health care costs were factored in.

"It hits individuals in the most productive years of their lives," says Dr. Angela Mailis-Gagnon, director of the comprehensive pain program at Toronto Western Hospital.

In 2001, Dr. Dwight Moulin of the University of Western Ontario Interdisciplinary Pain Program surveyed 340 people living with chronic pain and found the mean number of days pain left people unable to work in the last year was 9.3, but for those with severe pain, it rose to 16.

"Most people think it's like the flu (where you hurt all over) but it's not just the pain, it's everything that comes with it," Jessop says. "You often have zero energy, and when the pain comes, the fatigue gets worse."

FM has kept Jessop out of the office more than it's allowed her to be there. In the beginning, when she was able to get back to work, she pushed herself hard to perform as she always had. It took several crashes to learn she was doing more harm than good.

That changed in November 2001, when a stress-fueled flare-up of full-blown pain and fatigue forced her home. Her doctor urged her back as quickly as possible, so three weeks later she was working part-time. But she couldn't concentrate. Exhausted, her brain was in a fog.

"My biggest problem was reading. I do computer programming but I couldn't even read the manuals, let alone work out the logic of what I was doing," Jessop says.

Once she can get the fatigue under control, her cognitive function improves. But after 10 months of working part-time, Jessop's doctor and psychologist recommended she take a few months off. So from October 2002 to the end of January 2003, she was home.

"Then I went back eight hours a week, thinking I could increase it, but I could not," Jessop says. "By June we decided again that I should stop."

In a 2004 survey conducted by the American Chronic Pain Association, more than half of chronic pain sufferers reported it interfered with their ability to work.

Ten years ago, a review of long-term disability claims by London Life of Canada found that, in 1994 alone, private insurance companies paid out $46 million in fibromyalgia claims, $27 million for chronic fatigue claims and $30 million for repetitive strain injury claims.

When off sick or working part time, Jessop's salary is topped up by her long-term disability benefits. It's a financial relief, but she had to fight for it.

"All they had was a few letters from my doctor saying I'm fatigued. And me saying I'm fatigued," Jessop recalls. "(However) they want objective evidence like an X-ray or blood test -- something scientific. But other than how loudly you scream when they poke you, there isn't anything for fibro. Whining doesn't count."

In 2003, the Supreme Court of Canada ruled that excluding those disabled by chronic pain from workers' compensation granted to others breached the equality rights of the Charter of Rights.

Many chronic pain patients are unable to contribute financially to society, and studies have shown them to be heavy users of the health care system.

With help, it is possible for chronic pain sufferers to stay in the workplace. In March 2004, nine months after she left, Jessop gave it another try. She worked with an occupational therapist to adjust to days at the office.

The therapist taught Jessop stretches to do every 10 minutes that didn't disrupt her work but would alleviate some pain. She also settled on a gentle schedule in which her hours would gradually be increased.

Life with fibromyalgia is a constant balancing act and for Jessop, involves careful planning of her days. It takes very little, including a lack of sleep, for everything to go awry.

Of pain and fatigue, she says: "There's no expectation that it's ever going to go away. You don't know if it will be with you three hours or three years." Jessop says.

Dr. Ellen Thompson, an anesthetist at the Ottawa Hospital who has treated chronic pain for more than 25 years, says, "Having chronic pain is like having an alarm system that goes off incessantly," Thompson says.

"Chronic pain is not simple," says Dr. Angela Mailis-Gagnon, director of the comprehensive pain program at Toronto Western Hospital. "It's not a disorder of a muscle or simple body part. It's a complex disorder that brings in the brain and the personality fabric."

The European Federation of ISAP Chapters (ISAP-International Association for the Study of Pain) declared in 2001: "While acute pain may reasonably be considered a symptom ... chronic and recurrent pain ... is a disease in its own right."

It's estimated that 80% of doctor visits result from pain. Some global studies have reported chronic pain rates as high as 46%. In Canada, 17%-31% of adults suffer from it, depending on the study.

"Pain is not sexy," says Dr. Roman Jovey, president of the Canadian Pain Society. "It doesn't have the sex appeal of other medical conditions. When you're looking for funding and attention, heart disease gets the lion's share."

"However pain is also right up there," he says. "But patients tend to be fairly passive. They're struggling to survive, so they're not vocal."

Most chronic pain patients look perfectly healthy with no real evidence they're suffering. So not only is it lacking in sex appeal, it's largely an invisible disability.

Definition: Previously known as causalgia or RSD, reflex sympathetic dystrophy. Pain is caused by abnormal activity in the sympathetic nervous system.

Treatments: There are many strategies for relieving the pain, including topical analgesics, anti-depressants, and opioids. Physical therapy, sympathetic nerve block, or spinal cord stimulation are other possible approaches.

Treatments: Pain and inflammation medication, as well as chiropractic or physiotherapy, and perhaps more unconventional approaches including acupuncture. In some cases, surgery.

Definition: A common condition, characterized by widespread pain and musculoskeletal tenderness. The majority of sufferers (90%) are women, diagnosed in their 40s and 50s.

Number of people who suffer from the condition: Most people experience headaches from time to time, but close to 20% of Canadians know the agony of migraine headaches.

Definition: A musculoskeletal pain disorder which may involve a single muscle or group -- symptoms may be a burning, stabbing, aching or nagging sensation.

Treatments: Approaches geared to the individual patient, but may include pain medication, physical therapy (possibly massage therapy, or chiropractic), as well as medication to deal with consequences, including insomnia and depression.

Definition: Osteoarthritis significantly impacts psychosocial and physical function and is a leading cause of disability in later life. Pain, the most prominent symptom in most people with osteoarthritis, is the most important determinant of disability.

Treatments: Anti-depressant and anti-convulsant drugs. Non-surgical treatments, such as electrical nerve stimulation, as well as surgical options.

Definition: A condition where nerve damage generally starts in both feet, but may progress to calves, fingers and hands. Also known as Stocking and Glove Neuropathy.

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