By Jane Ehrhardt
“We're still so early in learning so much about the gut microbiome. It’s in its infancy right now,” says Carmen Lopez, MD, gastroenterologist with G.I. Associates of West Alabama. So far, 19 conditions from six systems or organs in the body—none of them the stomach—have shown an association to the health of the gut microbiome. They run from cardiovascular disease, Alzheimer’s, and rheumatoid arthritis to hyperthyroidism and multiple sclerosis.
As the largest surface of interaction between the external world and internal environment, knowledge of the GI tract continues to expand and accepted practices go out of date. Or some seem to have become forgotten, though they remain true.
Should aspirin be prescribed to help prevent colorectal cancer?
Patients taking aspirin for certain cardiovascular risk factors have shown a decreased rate of colorectal cancer. “Some of the early data seen in these patients had lower rates of colon cancer,” Lopez says. “But it's not yet to the point where we would automatically put someone who is at risk on aspirin.” Nonetheless, if a patient has another indication for aspirin, adding that it can also help protect from colon cancer might be useful motivator.
The caveat to colorectal screening
Starting colorectal screening at age 45 is now a given for every average-risk patient. “The caveat to this, though, is that if you have a family history of colorectal cancer, especially in a first-degree relative, then you should begin your screening at 10 years younger than the age of diagnosis of your relative or at age 40, whichever is younger,” Lopez says. So if a parent was diagnosed with colorectal cancer at age 45, then start screening that patient at age 35. If the parent was 60 years old when diagnosed, start at 40.
Diagnosing IBS
“There are three things I check for to make sure I really believe someone has IBS before just slapping that diagnosis on them,” Lopez says. “Whenever I suspect that they might have IBS with diarrhea, I always rule out celiac disease.” She also checks thyroid levels to rule out a thyroid condition leading to their diarrhea, and she checks for a stool inflammatory marker, such as a fecal calprotectin to make ensure they don't have inflammatory bowel disease.
Probiotics. Yes or no?
“Patients ask all the time whether or not they should be on probiotics,” Lopez says. “The answer to that question right now is ‘no’. We don't have enough data suggesting that probiotics are beneficial. The data is inconsistent. The biggest problem with studying probiotics is the large number of brands that use so many different strains and different numbers of bacteria. We don't know yet which probiotic is actually going to be the best probiotic. And my suspicion is that each individual patient is probably going to need some different combination of bacteria.
“If a patient is insistent on trying probiotics, I suggest they try one for 30 days. If they don't feel better, switch probiotics. I haven’t seen any evidence of any harm in probiotics. The only real negative is you are spending money on something that may not be helpful.”
How is IBS affected by a woman’s hormones?
“I don't think it's well-known that estrogen increases sensitivity to pain or anxiety and inflammation,” Lopez says. “During menstruation, women often report much more frequent symptoms, and menopause and hormone replacement worsen their symptoms. So if they have significant IBS symptoms, hormone replacement becomes a risk/benefit discussion with the primary care. Unfortunately, birth control hasn’t shown to help with IBS symptoms.”
What are primary cares missing about managing IBS?
“Probably the biggest thing would be offering patients the low FODMAP diet,” Lopez says. The diet eliminates high fermentable-carbohydrate foods for two to six weeks, then slowly reintroduces them one at a time to identify which foods trigger the IBS symptoms. The list of foods is long.
Primary care physicians could also recommend a natural over-the-counter peppermint oil. “It’s a supplement that has been proven to help with the abdominal pain discomfort and bloating associated with IBS,” Lopez says. “These are often two of my first go-tos that are really minimal risk and well tolerated.”
What’s next?
“As we go forward, I think we'll find that the gut microbiome is connected to everything—heart disease, Alzheimer's, mental health, obesity, diabetes,” Lopez says. “Right now, it's easy to focus on the problem that a patient is presenting with. But I think that in the future we’ll have more holistic thinking about gut health and its role in not just managing, but preventing some of these diseases.”
