Research Roundup: Reducing Food Allergy, Celiac and Heart Health, & More
The latest medical news for people with allergies and food sensitivities.
Reducing Food Allergy
Introducing babies to a wider range of foods in the first year of life might guard against asthma and food allergy. A European study, which followed children from birth to age six, showed babies exposed to fewer than four common foods in the first year had three times the risk for asthma and four times the risk for food allergy compared with tots introduced to six or more common foods. New guidelines by the American Academy of Allergy, Asthma and Immunology recommend earlier introduction (ages 4 to 6 months) of all foods. The study was published in April in the Journal of Allergy and Clinical Immunology.
Editor’s note: Consult with your pediatrician for the appropriate timing of food introduction.
Know Your Risk
Those individuals most at risk for celiac disease don’t know it, U.S. researchers found in a survey aimed at determining why celiac screening and diagnosis rates remain low. It’s estimated just 15 percent of celiacs in the United States are diagnosed.
Physician awareness of celiac symptoms and risk factors is critical but so is public awareness, say researchers. Family history of celiac disease, related autoimmune disorders like type-1 diabetes and Sjogren’s syndrome, symptoms like chronic diarrhea and abdominal pain, and irritable bowel syndrome (IBS), early-onset osteoporosis and unexplained infertility are all important risk factors. The study was published in March in BMC Gastroenterology.
You Can’t Always “See” Celiac
Endoscopy without biopsy may miss many new cases of celiac disease, according to a new Australian study. Half of all new celiac patients had normal-looking mucosa during endoscopy and nearly a quarter had atypical (non-GI) symptoms. Researchers estimate at least 10 percent of new celiac cases are likely to go undiagnosed at routine endoscopy. They urge screening with celiac antibody (blood) tests before performing an endoscopy to improve diagnosis rates.
Endoscopy involves threading a tiny camera mounted on a long, flexible tube through the digestive system for visual examination. During endoscopy, small pieces of tissue—biopsy—can be removed for later examination with a microscope. Celiac guidelines call for taking four biopsy samples from the duodenum (one from the bulb and three from the second part), since damage due to celiac can be patchy. The study was published in March in PLoSOne.
Peanut Allergy Over-Diagnosis
Children with a peanut-allergic older sibling may be at risk of being labeled peanut allergic without adequate testing, Canadian researchers say. In their study, children born after an older sibling’s peanut allergy diagnosis were five times more likely to completely avoid peanuts and 12 times more likely to be diagnosed as peanut allergic without a history of reacting to peanuts or sufficient testing for peanut allergy. Findings were based on a survey of families taking part in the Canadian Peanut Allergy Registry. Results were presented last October at the Canadian Society of Allergy and Clinical Immunology’s Annual Scientific Meeting.
A new study suggests people diagnosed with potential celiac may want to hold off on the gluten-free diet. Potential celiac refers to having celiac antibodies (blood test results) but a normal intestinal biopsy. It’s unclear how common this condition is—and if affected individuals should immediately start a gluten-free diet.
Nine years after being diagnosed with potential celiac, two-thirds of the children in this study still hadn’t developed the intestinal damage characteristic of celiac disease, despite continuing a regular gluten-containing diet. (All children were symptom-free when they started the study.) The study was published in April in the American Journal of Gastroenterology.
Celiac and Heart Health
Celiacs had twice the risk of coronary artery disease (CAD) compared with the general population, according to a new U.S. study. This doubling of CAD risk was even seen in younger celiac patients (under age 65). Findings suggest that chronic inflammation, whether from an infection or a disease like celiac, can have adverse effects on CAD and heart health in general, say researchers. Further studies are needed to confirm the association and to determine if celiac patients need more intense risk factor modification (i.e., closer cholesterol monitoring). For now, researchers say doctors and patients should be aware of the link. Results were presented in March at the American College of Cardiology’s 63rd Annual Scientific Session.
Gluten and Depression
A major effect of gluten in non-celiac gluten sensitivity (NCGS) may be on mental state, according to a new Australian study. Gluten induced more feelings of depression than whey (a milk protein) or nothing at all (placebo) when study participants were challenged with each food. Participants all had self-diagnosed NCGS and didn’t know when they were being given gluten versus whey (as supplements). Interestingly, gastrointestinal symptoms were similar across the three-day diet challenges. Findings might help explain why many NCGS patients “feel better” on a gluten-free diet despite ongoing gastrointestinal symptoms. The study was published in May in Alimentary Pharma-cology & Therapeutics.
IBS Raises Celiac Risk
Screening for celiac disease in children with irritable bowel syndrome (IBS) may be warranted. According to a large Italian study, kids with IBS are four times more likely to have celiac disease than those without IBS.
Symptoms of celiac and IBS can closely overlap, particularly in children, who tend to have “classic” celiac symptoms like diarrhea and abdominal pain. Research in adults with IBS has shown a higher rate of celiac but it wasn’t known if this was also the case in children until now. The study was published in April in JAMA Pediatrics.
Gut Damage Evident
The gluten-free diet isn’t enough to control symptoms and intestinal damage for many with celiac disease, according to a troubling new study presented in May at Digestive Diseases Week. The study involved 117 U.S. celiacs taking part in the CeliAction study, which is evaluating ALV003, an investigational treatment for celiac disease. Nearly all participants who reported moderate-to-severe celiac symptoms (e.g., abdominal pain, bloating, diarrhea) at least once a month had abnormal intestinal findings when biopsied. Over half—65 percent—had intestinal damage consistent with full-blown, untreated celiac disease, despite having been gluten-free a year or more. (In many cases, antibody tests were negative.) This study follows research conducted at the Mayo Clinic in 2010, which found a third of adult celiacs had ongoing intestinal damage after five years on the gluten-free diet.
More About Gluten Sensitivity
A recent survey of individuals who consider themselves gluten sensitive showed that 3 out of 4 respondents did not fulfill the criteria for a non-celiac gluten sensitivity (NCGS) diagnosis. Most of these participants (62 percent) didn’t meet NCGS criteria because they had not adequately ruled out celiac disease, while others (24 percent) had ongoing symptoms despite going gluten-free and/or they weren’t consistently excluding gluten (27 percent) from their diet. Among those who did fulfill NCGS criteria, their knowledge of and adherence to the gluten-free diet were excellent.
A NCGS diagnosis requires ruling out celiac (and, ideally, wheat allergy) and observing an improvement in symptoms on the gluten-free diet. Results were published in April in Nutrition in Clinical Practice.
Senior medical correspondent Christine Boyd lives in Baltimore.