A Most Brittle Hypothesis
Understanding why the unwelcome diagnosis of celiac disease often carries the further complication of osteoporosis
Something was seriously wrong with Debbie Adams, but her doctors were stumped. What was this mystery illness that had triggered such an odd mix of problems: diarrhea, bloating, fatigue, sleeplessness, irritability, anemia and severe weight loss? Still another symptom was osteoporosis, which had already stolen some 50 percent of her bone mass. And at that point, seven years ago, she was just 40 years old.
Weak and frustrated, Adams was visiting a bone specialist at the School of Medicine when she heard about a new research study. The NIH had funded gastroenterologist William F. Stenson, MD, professor of medicine, to examine 800 adults, half with osteoporosis and half with normal bone density, for an "under-investigated" problem: celiac disease. Adams became the first participant to test positive for this little-known autoimmune disease in which patients respond abnormally to gluten, a protein found in such grains as wheat and barley. This response results in injury to the lining of the intestines, so certain nutrients cannot be absorbed. Osteoporosis in celiac disease patients is a product of impaired absorption of dietary calcium.
Gluten-induced intestinal injury sets off a confusing, sometimes contradictory cascade of effects throughout the body. While many patients have diarrhea, a few have constipation; instead of losing weight, some gain. They may develop depression or anxiety, anemia, abdominal pain or an itchy rash; some women may find it difficult to conceive. Happily, the only treatment for this disease — adhering faithfully to a lifelong, gluten-free diet — can reverse these symptoms dramatically.
"Within six months on a gluten-free diet, I had regained 11 percent of my bone density," says Adams, a teacher and mother of three in Belleville IL. "Today, I'm happier, with more energy and a more positive view of life, and I've also regained much-needed weight and then some. I say now that once I turned 40, was diagnosed with celiac disease and went gluten-free, I started getting younger."
Despite its impact, celiac disease is under-diagnosed and poorly understood, even among some physicians. A 2004 NIH report estimated that 3 million Americans are affected, though 97 percent do not know it. Once Stenson published his study results, showing that 3 to 5 percent of osteoporosis patients had it, compared to one-half of one percent of those with normal bone density, he was flooded with celiac referrals.
"That tells me there's more celiac disease than people appreciate," says Stenson, the Nicholas V. Costrini Professor of Gastroenterology and Inflammatory Bowel Disease. "I think there are clinical circumstances in which it should be considered but is not now widely considered, and patients with iron deficiency anemia or osteoporosis should be tested."
Pediatricians also have become more aware of celiac disease, say James P. Keating, MD, and Robert J. Rothbaum, MD, pediatric gastroenterologists at St. Louis Children's Hospital. Last year, the two participated in a continuing medical education program, "Emerging Concepts in Celiac Disease." During discussion, they stressed that it can appear at any age and in many forms. "We once estimated the prevalence of celiac disease as one in 8,000 people," says Keating, the W. McKim Marriott Professor of Pediatrics, "while now we know that it's around 1 in 100."
Certain groups are more genetically susceptible. Rarely do African-Americans develop it; for the most part, it is found in Caucasians. People with European ancestry are more at risk, and those with ancestors from western Ireland are the most vulnerable of all, since 1 in 60 there have it. It tends to run in families, especially in first-degree relatives. Down Syndrome and Type l diabetes also are linked to a higher risk for the disease.
"Over the past few years, awareness has significantly increased," says Nancy C. Bradley, RD, LD, CDE, a clinical dietitian at the School of Medicine who sees adult patients.
Now physicians have access to a successful screening blood test, tissue transglutaminase (tTG), which pinpoints 95 percent of cases. A negative tTG test effectively excludes the diagnosis of celiac disease; physicians rely on the gold standard of celiac tests — a biopsy of the small intestine through upper gastrointestinal endoscopy, performed before a patient has given up foods containing gluten — to confirm a positive diagnosis.
"Once people start to alter their diet, it alters the result of all these tests," says Rothbaum, professor of pediatrics and clinical director of pediatric gastroenterology and nutrition. "So it is important to have as clean information as possible when the diagnosis is established."
This diagnosis sets patients on a difficult dietary path, since the gluten-free regimen is hard to follow. Children may find it especially tough. "It means going to parties with a kind of sign on the child: no cookies, no cake," says Keating. "If the person didn't feel sick before diagnosis, then the disease becomes the diet, instead of the celiac problem."
After identifying the disease, physicians often refer patients to a dietitian who can explain which foods contain gluten. Not only is it present in obvious products — bread, pasta, pastries — it can lurk in unexpected places, such as non-distilled white vinegar, most soy sauces, even makeup and medication. Going to restaurants becomes a burden, as celiac sufferers must quiz wait staff about ingredients or possible cross-contamination of food by contact with gluten-containing items.
"One thing we tell patients is that they have to be religiously observant about the diet," says Stenson. "Removing 90 percent of the gluten from your diet is the same as doing nothing. You have to remove all of it."
Failure to do so means further intestinal damage and possibly an increased risk of intestinal lymphoma. "I tell people to think of it as a poison in their system that is doing damage," says Bradley, who also works in Diabetes Education and Nutrition Counseling at Barnes-Jewish West County Hospital.
Adams, who helped found the Bi-State Celiac Support Group (bscsg.org) after her diagnosis, has seen remarkable recoveries among fellow sufferers. One woman's migraine headaches disappeared; another, undergoing tests for multiple sclerosis, suddenly felt her chronic fatigue vanish, she says.
"Some celiac patients come to see me, upset about the diagnosis," says Bradley. "But overall, if they have had symptoms, they feel relief that they finally have an answer, and there is something they can do about it."