Previous issues of this newsletter have contained articles about the importance of the gut microbiome and human health in general and more specifically in good immune function. In this regard the use (and overuse) of antibiotics has come under intense scrutiny. This includes therapeutic antibiotics and those used in our food production. The premise here is that the antibiotics kill off some of our healthy microbiome and can lead to an overgrowth of “undesirables”.
A recent article published in “Nature” details research on the impact of non-antibiotic medications on the healthy microbiome. The investigators screened over 1,000 different medicines and found that 24% of them alter the healthy microbiome. The drugs that seemed to be the worst were antipsychotics and other psychoactive drugs, proton pump inhibitors, anti-cancer drugs and hormones.
What is a bit unsettling, is that this same research group has found preliminary evidence that an altered microbiome can promote some psychiatric and neurological diseases. So, the concern is that maybe the treatment that is supposed to help the condition might also contribute to it.
The researchers say more studies are needed to clarify these issues.
The answer is no, yes, or maybe so. I’m not trying to be obtuse, but the answer is different for different people.
Let’s start with the dry eye syndrome. It is very common and affects millions of Americans. Also, it can vary in severity from a mild nuisance to a vision altering severe condition. The common denominator for all people with dry eye syndrome, is compromised ocular lubrication. But, the condition has many causes which can overlap and interact.
Our tears are made by two different tear glands: the lacrimal glands which make the salt water component and the meibomian glands which make the oil component. Dry eye syndrome can be due to inadequate oil production. This imbalance can actually be worsened when the lacrimal glands over-produce the salt water which ends up diluting the oil further. And paradoxically someone with dry eyes might be “tearful”.
Dry eye syndrome can also be due to inadequate lacrimal output. The most common cause for this is certain rheumatologic syndromes especially Sjogren’s Syndrome. But lacrimal deficiency can also occur due to aging, contact lenses, and the drying effect of certain medications such as antihistamines.
Allergic individuals may not have ocular allergy until they develop dry eye syndrome, which leads to a paucity of tears and therefore impedes the natural removal process of allergens from the eye. Then if they take antihistamines to help their allergies they can worsen the drying of the eyes. Other medicines that can contribute to dry eyes include: diuretics, beta – blockers, some antidepressants, birth control pills and some herbal supplements, especially echinacea.
Finally, people who have a reduced blink rate (most commonly seen in Parkinson’s disease) don’t renew the protective tear film on the eyes and experience dry eye issues.
The immune system was once considered an independent, self-regulated system. But research over the past ten years has found that like most of the rest of the human body, it too is under the control of our nervous system.
Some of the early research in this regard was designed to understand why we seem more prone to get sick if we are under stress or depressed. As it turns out the brain does have significant control over certain aspects of the immune system. The brain uses the autonomic (also called automatic) nervous system to exert this influence. One of the main autonomic nerves is the vagus. Japanese scientists at Osaka University have discovered that using mild electrostimulation of the vagus nerve reduces immune mediated inflammation. Preliminary studies in rheumatoid arthritis and Crohn’s disease have shown improvement in both diseases with this therapy. Studies are also underway to determine benefit in reducing the inflammation that causes asthma.
One reason this research is so exciting is that unlike most anti-inflammatory drugs in current use, electrostimulation does not cause immune suppression and therefore avoids the increased risk of infection due to drug therapy.
The FDA has recently approved Aimovig (Erenumab) a once-a-month injection to prevent migraines. Aimovig is a monoclonal antibody that targets the calcitonin gene-related peptide receptor (CGRP). CGRP is a neurotransmitter that dilates blood vessels and stimulates pain. It was discovered that levels of CGRP go way up in people experiencing migraines. By blocking the receptor for CGRP the Aimovig is able to prevent headaches.
Since Aimovig is a preventative agent, it is currently only recommended for patients with frequent severe migraines or with chronic migraines. The cost of each injection is $600.00.
A recent study in Europe was done on people with mild-persistent asthma. The study compared daily use of a combination inhaler with long lasting bronchodilator and steroid versus just using the inhaler when the asthma started to flare up. The rate of severe exacerbation of the asthma requiring either an ER visit or treatment with oral steroids was the same in both groups.
Auvi–Q, a form of adrenaline auto injector has recently come out with a lower dose injector for emergency treatment of anaphylaxis in children weighing less than 33 pounds. It contains .1 mg of epinephrine and has a shorter needle (to avoid hitting the bone when injected). Previous to this the only other available doses were .15 mg for people 30 to 60 pounds and .30 mg for people over 60 pounds.