Researchers have a new theory on why some kids get unexplained tummy aches.
In some people, the small intestine is unable to efficiently break down fructose (and sometimes other forms of sugar). This problem is sometimes referred to as fructose intolerance. The undigested fructose passes into the large intestine, where it is broken down by bacteria. A by-product of this process is the creation of carbon dioxide and hydrogen. These two gases build up in the intestine, causing bloating, gas, pain and diarrhea. In some cases, the problem can affect absorption of important nutrients, like calcium and iron.
Researchers estimate about 33 percent of Americans have some level of sensitivity to sugar, most commonly to fructose, but the symptoms are often vague. Some people with fructose intolerance can eat small amounts of the sugar and not have any problems, making diagnosis even trickier.
Daniel Lustig, M.D., Pediatric Gastroenterologist at Mary Bridge Children’s Health Center in Tacoma, WA, says patients with chronic digestive problems should have a physician’s evaluation to rule out other possible causes of the symptoms, like Celiac disease or Crohn’s disease. Once those conditions have been ruled out, he recommends a diagnostic tool called the breath hydrogen test.
A patient is given a dose of fructose. Then, periodically, he/she breathes into an air collection bag. The gases from the bag are retrieved and analyzed for the presence of hydrogen (one of the gases given off when fructose is broken down in the large intestine). Patients whose hydrogen levels exceed 20 points beyond a baseline reading are likely to be fructose intolerant.
Lustig explains the main treatment of fructose intolerance is avoidance of foods containing fructose. That includes fruits, fruit juices, sodas and processed foods and drinks with high fructose corn syrup. Since fructose is in so many foods, it can be tricky to find and hard to avoid.
Lustig recently performed a study to look at possible fructose intolerance in 245 children and adolescents (ages 2 to 18) with unexplained chronic abdominal pain, gas or bloating. The breath hydrogen test found that nearly 54 percent of the participants tested positive for fructose intolerance. Lustig says the problem appeared to be especially high among teen girls.
Those who were judged to be fructose intolerant were given advice on using a low-fructose diet. The investigators found that nearly 68 percent of those who followed the recommended diet had an improvement or resolution in their symptoms.
About 10 to 15 percent of children experience recurrent abdominal pain, the researchers said. The pain can be due to irritable bowel syndrome — which is usually relieved by defecation — or can be “functional abdominal pain,” which is not explained by another disease. While LGG has been tested before in children with abdominal pain, the studies were small and showed mixed results. The new study, which involved 141 children with irritable bowel syndrome or functional abdominal pain, was conducted in Italy between 2004 and 2008. Researchers gave the kids either the probiotic or a placebo for eight weeks. Neither the doctors nor the patients were aware which treatment they received.
Following the treatment, the patients were followed up for another 8 weeks. During the treatment and follow-up, the severity and frequency of abdominal pain decreased for both groups, but the probiotic group experienced a more drastic reduction. For instance, after 12 weeks, patients who took the probiotic reported experiencing, on average, 1.1 episodes of pain per week, compared with 3.7 weekly episodes before the treatment. Those who took the placebo reported experiencing 2.2 pain episodes per week, compared with 3.5 episodes initially.
And a greater percentage of parents of children who took the probiotic reported that their children experienced a decline in pain,compared with those whose kids took the placebo. Among kids who took the probiotic, it was mostly children with irritable bowel syndrome who showed improvements, the researchers said.
Why does it work?
The results suggest LGG may be specifically beneficial for those with irritable bowel syndrome, the researchers said. It's possible that children with irritable bowel syndrome have an imbalance of good and bad bacteria in their guts, which contributes to the pain, and the probiotics relieves pain by restoring the proper balance, Francavilla said. Probiotics have also been suggested to reduce inflammation in the gut, as well as stimulate the release of analgesic substances that relieve pain. The researchers noted they cannot be sure whether the beneficial effects will last for more than a few weeks after treatment is stopped.
The results were published in the journal Pediatrics.
Researchers employed imaging techniques to examine and analyze brain anatomical differences between 55 female IBS patients and 48 female control subjects. Patients had moderate IBS severity, with disease duration from one to 34 years (average 11 years). The average age of the participants was 31.
Investigators found both increases and decreases of brain grey matter in specific cortical brain regions.
Even after accounting for additional factors such as anxiety and depression, researchers still discovered differences between IBS patients and control subjects in areas of the brain involved in cognitive and evaluative functions, including the prefrontal and posterior parietal cortices, and in the posterior insula, which represents the primary viscerosensory cortex receiving sensory information from the gastrointestinal tract.
“The grey-matter changes in the posterior insula are particularly interesting since they may play a role in central pain amplification for IBS patients,” said study author David A. Seminowicz, Ph.D., of the Alan Edwards Centre for Research on Pain at McGill University. “This particular finding may point to a specific brain difference or abnormality that plays a role in heightening pain signals that reach the brain from the gut.”
Decreases in grey matter in IBS patients occurred in several regions involved in attentional brain processes, which decide what the body should pay attention to. The thalamus and midbrain also showed reductions, including a region – the periaqueductal grey – that plays a major role in suppressing pain.
“Reductions of grey matter in these key areas may demonstrate an inability of the brain to effectively inhibit pain responses,” Seminowicz said.
The observed decreases in brain grey matter were consistent across IBS patient sub-groups, such as those experiencing more diarrhea-like symptoms than constipation.
“We noticed that the structural brain changes varied between patients who characterized their symptoms primarily as pain, rather than non-painful discomfort,” said Mayer, director of the UCLA Center for Neurobiology of Stress. “In contrast, the length of time a patient has had IBS was not related to these structural brain changes.”
Mayer added that the next steps in the research will include exploring whether genes can be identified that are related to these structural brain changes. In addition, there is a need to increase the study sample size to address male-female differences and to determine if these brain changes are a cause or consequence of having IBS.
The study was funded by the National Institutes of Health.
Additional authors include M. Catherine Bushnell, Ph.D., of McGill University, and Jennifer B. Labus, Joshua A. Bueller, Kirsten Tillisch and Bruce D. Naliboff, Ph.D., all of UCLA.
The study, to be published in the journal Pain, found that particular areas of the brain were less active as meditators anticipated pain, as induced by a laser device. Those with longer meditation experience (up to 35 years) showed the least anticipation of the laser pain.
Dr Brown, who is based in the University's School of Translational Medicine, found that people who meditate also showed unusual activity during anticipation of pain in part of the prefrontal cortex, a brain region known to be involved in controlling attention and thought processes when potential threats are perceived.
He said: “The results of the study confirm how we suspected meditation might affect the brain. Meditation trains the brain to be more present-focused and therefore to spend less time anticipating future negative events. This may be why meditation is effective at reducing the recurrence of depression, which makes chronic pain considerably worse.”
Dr Brown said the findings should encourage further research into how the brain is changed by meditation practice. He said: “Although we found that meditators anticipate pain less and find pain less unpleasant, it's not clear precisely how meditation changes brain function over time to produce these effects.
“However, the importance of developing new treatments for chronic pain is clear: 40% of people who suffer from chronic pain report inadequate management of their pain problem.”
In the UK, more than 10 million adults consult their GP each year with arthritis and related conditions. The estimated annual direct cost of these conditions to health and social services is £5.7 billion.
Study co-author Professor Anthony Jones said: “One might argue that if a therapy works, then why should we care how it works? But it may be surprising to learn that the mechanisms of action of many current therapies are largely unknown, a fact that hinders the development of new treatments. Understanding how meditation works would help improve this method of treatment and help in the development of new therapies.
“There may also be some types of patient with chronic pain who benefit more from meditation-based therapies than others. If we can find out the mechanism of action of meditation for reducing pain, we may be able to screen patients in the future for deficiencies in that mechanism, allowing us to target the treatment to those people.
For this study, Chenchen Wang, M.D., M.Sc., and colleagues recruited 40 patients from the greater Boston area with confirmed knee OA who were in otherwise good health. The mean age of participants was 65 years with a mean body mass index of 30.0 kg/m2. Patients were randomly selected and 20 were asked to participate in 60-minute Yang style Tai Chi sessions twice weekly for 12 weeks. Each session included: a 10-minute self-massage and a review of Tai Chi principles; 30 minutes of Tai Chi movement; 10 minutes of breathing technique; and 10 minutes of relaxation.
The remaining 20 participants assigned to the control group attended two 60-minute class sessions per week for 12 weeks. Each control session included 40 minutes of instruction covering OA as a disease, diet and nutrition, therapies to treat OA, or physical and mental health education. The final 20 minutes consisted of stretching exercises involving the upper body, trunk, and lower body, with each stretch being held for 10-15 seconds.
At the end of the 12-week period, patients practicing Tai Chi exhibited a significant decrease in knee pain compared with those in the control group. Using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain scale, researchers noted a -118.80 reduction in pain from baseline between the Tai Chi and control group. Researchers also observed improved physical function, self-efficacy, depression, and health status for knee OA in subjects in the Tai Chi group. “Our observations emphasize a need to further evaluate the biologic mechanisms and approaches of Tai Chi to extend its benefits to a broader population,” concluded Dr. Wang.
The new study comprised 366 people with RA from eight separate trials. Fasting followed by eating a vegetarian diet for 13 months or eating a Mediterranean style diet replete with fruits, vegetables, healthy fats, and legumes for 12 weeks may relieve pain, the study showed. These diets did not improve morning joint stiffness or physical function when compared to regular diets.
There was not enough data to draw any conclusions about how vegan and/or elimination diets affect RA symptoms.
The positive changes seen with vegetarian and Mediterranean diets may be a result of simply adapting a healthier way of eating as opposed to any specific diet, the study researchers conclude.
People with RA who were put on special diets were more likely to drop out of the studies, suggesting that some people may have difficulty adhering to the eating plans.
Some special diets also resulted in weight loss which may not always be a good thing people with RA who are already at risk for nutritional shortfalls.
“There is a need for more and better research on dietary interventions for RA,” conclude researchers led by Geir Smedslund, PhD, a senior researcher at the Centre for Rehabilitation in Rheumatology at the Diakonhjemmet Hospital in Oslo, Norway.