番茄社区

Expert Critique

FROM THE ASCO Reading Room

Aylin Tansel, MD Gastroenterology Fellow Baylor College of Medicine

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder characterized by pain or discomfort and altered bowel function. It is more common among women, and has been estimated to affect as much as 15% of the U.S. population, generally highest among adults of working age, and more than three quarters of affected patients remain undiagnosed. It is associated with significant costs, both direct and indirect, that affect patients, providers, and healthcare systems.

The direct costs include diagnostic tests, medications, and physician visits -- estimated to range from $1.5 billion to $10 billion. Patients with IBS have been found to have a greater number of healthcare visits per year than population controls. The indirect costs, including diminished productivity or missed work, are estimated to be as high as $20 billion, although this estimate is based on IBS patients who sought medical attention and is likely to be much higher. Patients with IBS tend to use a wide range of medications for relief of symptoms. Diagnosing and managing IBS can be difficult due to the lack of a diagnostic marker and effective treatment options.

The primary components of indirect cost for patients with IBS are missed work, decreased work productivity, and diminished health-related quality of life. Estimates have placed IBS as the second leading cause of absenteeism -- ill health has been recorded for an average of 6.4 days in patients with IBS compared with 3.0 days in matched controls of patients without IBS. In terms of the impact on patients' lives, quality of life has been low and is similar to that for patients with other chronic conditions such as chronic depression. Unfortunately, most patients with IBS are not formally diagnosed, or are diagnosed much later than their initial presentation of symptoms.

In summary, IBS imposes a significant socioeconomic burden. Development of evidence-based guidelines aim to help promote early diagnosis of IBS and may result in decreasing some of the economic burden. Educational awareness programs have been shown to reduce costs associated with other long-term disorders, and the implementation of programs on patients for IBS may have similar results.

Full Critique

Irritable bowel syndrome (IBS) affects at least 35 million Americans, and inadequately controlled, can sabotage patients' quality of life and earning power, curtailing workplace and educational productiveness.

In terms of direct U.S. healthcare costs, found that IBS added more than $1.3 billion annually, a figure that has doubtless risen over the past 15 years.

"IBS is not a benign condition," , chief of the Division of Gastroenterology and director of the USA Digestive Health Center of the University of South Alabama Health System in Mobile, told 番茄社区. "Making a confident and streamlined IBS diagnosis based on established clinical criteria and executing effective evidence-based therapy is very likely to have a positive impact on these costs."

Work and School

In , Cash and colleagues reported in 2005 that the financial burden for IBS patients is similar to that for patients with other widespread chronic conditions such as asthma, migraine, hypertension, and congestive heart failure, including both absenteeism (days missed from work) and "presenteeism" (reduced productivity at work and school).

In another interview, , of Northwestern University's Feinberg School of Medicine in Chicago, said that severe IBS symptoms can seriously impair functionality: "This relates to concerns regarding urgency, proximity to bathrooms, and an inability to complete longer tasks due to recurrent urges/needs to defecate. Some patients may spend a few hours in the bathroom every morning before they feel as though they are 'safe' to go to work, or avoid eating as they know -- or fear -- that they will be rushing to a bathroom soon."

Brenner said he sees some patients who have chosen to find jobs that allow them to work from home to compensate for the limitations.

"There are a number of arenas to consider, and some are a little hard to measure," noted Cash. "There's not a huge amount of information on the true dollars-and-cents impact."

For one thing, before even consulting a physician most IBS patients have incurred unmeasured costs for various over-the-counter remedies including analgesics, antispasmodics, antidiarrheals, laxatives, and probiotics. And then there are the transportation costs for IBS-related doctor and hospital visits.

In the American Gastroenterological Association's Dec. 2015 survey of 3,524 patients, IBS led to a monthly average of 2 missed days of school or work and 9 days of impaired occupational productivity.

In , Caroline Canavan et al reported that as far back as 1998, one national U.S. company calculated the annual costs of IBS-associated absenteeism at $901 per patient, which was 70% more than for non-IBS patients. In 2005, another firm put that per-patient cost at $7,737.

According to by Anne Peery and colleagues, U.S patients made a total of 2,403,751 physician, emergency room, and outpatient medical visits for IBS in 2010.

Diagnostic Difficulties

The diagnostic process can also be costly: The , published in Oct. 2016, noted that it can take an average of 4 years to achieve a positive diagnosis of IBS, with many patients undergoing a battery of diagnostic procedures. "IBS is a diagnosis of exclusion, and often a lot of tests are done to rule out organic disease," said Cash.

He pointed to the Canavan et al study, which reported that during the year of diagnosis, IBS patients will have an average of six blood tests, one out-patient procedure, and one radiological test specifically related to their IBS.

In by the Canadian Society of Intestinal Research of almost 3,000 IBS patients or their parents, the most common diagnostic test ordered for IBS-like symptoms was colonoscopy (61%), followed by lab tests (36%), gastroscopy (30%), and ultrasound (28%). And 48% of respondents said patients sought healthcare for IBS once or twice a year, while 17% did so three to five times annually. In addition, 12% of respondents had been hospital­ized for IBS-related reasons.

The direct costs are exorbitant," said Brenner. "Numerous unnecessary studies are performed, many multiple times by different MDs, before a true diagnosis is made. On average, an individual may see four physicians before the diagnosis of IBS is made, and it can take years before an individual receives a definitive diagnosis." Complicating diagnosis is that even in some medical circles, IBS is still dismissed as a psychological disorder.

Then there is the associated surgery. Cash noted that the rates for abdominal surgery are higher in those with IBS than in those without, with IBS patients receiving twice as many appendectomies and hysterectomies, as well as two to three times as many cholecystectomies as non-IBS sufferers. According to Canavan and colleagues, about a quarter of IBS patients have gynecologic surgery and about a third have appendectomy or cholecystectomy.

IBS-C versus IBS-D

As for the relative costs of constipation-predominant IBS (IBS-C) versus diarrhea-predominant IBS (IBS-D), Cash said, "there are no data comparing the two, but my instinct is that IBS-D has the greater economic burden." First, the direct costs are likely higher because of the diagnostic requirements: "There are more organic diseases that manifest with diarrhea than with constipation -- celiac disease and microscopic colitis, for example -- and the Rome IV criteria list more tests for these presenting with IBS-D symptoms."

In addition, the fear of diarrhea urgency and incontinence in the workplace may fuel more costly absenteeism. "So it makes sense that IBS-D is more burdensome, but the difference has not been carefully measured, to the best of my knowledge," Cash added.

Some research has shown that both types add substantial incremental costs to the healthcare system. While direct cost comparisons of IBS-D and IBS-C are not available, two separate insurance-based studies have reported a similar increase in healthcare costs for patients with both types.

In one industry-led published in 2016 of 19,653 commercially insured IBS-D patients and 19,653 matched controls, Jessica Buono and colleagues found that IBS-D patients had a significantly higher mean annual number of hospitalizations, emergency and office visits, and 30-day prescription fills.

Mean annual all-cause healthcare costs for IBS-D patients were $13,038, with 58.4% attributable to office visits and other outpatient services and tests. About 20% of the costs were attributable to prescriptions, inpatient admissions (13.6%), and emergency department visits (8.5%). Adjusted incremental annual all-cause costs associated with IBS-D were $2,268: $9,436 for IBS-D patients versus $7,169 for matched controls per patient per year. Of these, 78% were due to medical costs and 22% to prescription fillings.

A by Jalpa Doshi et al in 2014 of 7,652 of commercially insured IBS-C patients and controls found that the mean annual all-cause healthcare costs for IBS-C patients were $11,182 – more than half for physician and outpatients visits. Adjusted incremental annual all-cause healthcare costs were $3,856: $8,621 for IBS-C patients versus $4,765 for controls per patient per year. Of these costs, 78.1% were due to medical services and 21.9% to prescriptions.

Frustration for All

Despite the clear economic burden, IBS seems not yet to be fully recognized as the direct and indirect driver of costs it is, and this in turn can impact the way physicians prescribe.

"It's very frustrating for clinicians and patients," Cash said. "Although there are now four or five very proven pharmacologic therapies based on large, randomized controlled trials and approved by the FDA for IBS, we still fight a common battle with insurers when we write for these medications. It's not uncommon for payers to require patients to have tried several non-evidence-based therapies such as antispasmodics, antidiarrheals, and stool activators first. Yet there is very little evidence to suggest these are effective on a broad base -- especially for the multiple symptoms of IBS -- whereas the FDA-approved agents have a proven wide base of efficacy."

Although rigorous trials have shown that most of the newer evidence-based therapies improve both abdominal symptoms and bowel problems, these agents are prohibitively expensive for patients with limited insurance coverage. "Some of the newer FDA-approved therapies can cost an individual $800 to $1,200 out-of-pocket, and with rare exceptions, these are not affordable," said Brenner. "Thus, patients can't achieve their symptomatic goals, and physicians are limited in what they can truly offer. And without improvements in symptoms, the direct and indirect costs of this disorder are likely to continue to rise."

While the quality-of-life impact of IBS is gaining recognition, gastroenterologists hope greater awareness of the syndrome's true economic burden will help streamline diagnosis, expand first-line treatment with proven agents, and ultimately reduce overall costs.