In Health: Immune Struck
Janko Nikolich-Žugich, M.D.
In Health: Immune Struck
Many Americans seek a longer life, and every year more of us surpass 100 years. However, lifespan is only half the picture; healthspan should be of equal or paramount importance. “We have managed to extend lifespan quite a bit, but the health-
span, as we call it, is really the quality of life. It’s what everybody wants,” explains Janko Nikolich-Žugich, M.D., Ph.D., who is the Co-Director of the UA Center on Aging, Elizabeth Bowman Professor and Head of the Department of Immunobiology, University of Arizona College of Medicine, a member of the UA BIO5 Institute, and Chairman of the Board & CEO of the American Aging Association. “Nobody wants to live another twenty years and be miserable with several chronic diseases.”
The guiding light of healthspan is our immune system. It’s our protection from the environment. Within the immune system are white blood cells, which protect the body from foreign pathogens. One type of white blood cell is the T cell, learning and recalling strategies of defense throughout our life. For this to work efficiently we must elicit the assistance of naïve T cells. “We call the cells naïve T cells because they have never seen their microbe before,” says Dr. Nikolich-Žugich. “The way that this works is that we’ve got a huge army of these cells that is very, very diverse and capable of recognizing just about any microbe that’s going to attack us. In our youth we don’t have a problem because our army is chock full of new recruits that are there to fight off these new infections but starting after puberty there begins an almost ten-fold drop in the ability to make these cells.”
After successful remediation of a foreign invader, some naïve T cells rewire themselves to become memory T cells. When the immune system encounters the same or very similar pathogens, the memory T cells can recall the effective strategies and quickly mount a defense.
As we age the production of naïve T cells continues to drop. Consequently, protection from new infections and the response to known infections decreases. “Those that are the most dangerous are the ones that people have not experienced in their life. Older people have a very hard time dealing with a completely new virus or bacteria that has been introduced into the population,” states Dr. Nikolich-Žugich. Although memory T cells survive almost indefinitely, naïve T cells are necessary to continue to fight new pathogens. From our white blood cells, the cells that fight infections are being generated in our 50s at one-thousandth the rate of our youth. “The influenza virus is typically a very serious problem for older communities. The reason why it’s a problem is because the virus changes, so the fact that we had it once doesn’t protect us from a new variant.” Although the immune system often can adapt to changing infectious diseases, it is less efficient at an older age. Thus, when diseases mutate they can cause lengthier recovery times. Or when infections strike simultaneously, or before new production of cells, the results can be devastating. “The good news is they’re not completely stopped and that gives us possibilities to try and rejuvenate the immune system,” relays Dr. Nikolich-Žugich. “We have an active project right now, and we’re hoping to get substantial funding to continue, to study how to rejuvenate the immune system and to reignite new production as well as to improve function of these cells.”
On its own the immune system can fight, learn, recall and develop a vast repository of strategies to fight infections. With the help of medical science, the immune system can prepare for an invasion of deadly pathogens by way of immunizations. Two ways that immunizations work is by introducing active or inactive viruses. Inactivated and attenuated (“live”) vaccines initiate a response by the immune system to develop defenses, similar to contracting the virus. Inactivated vaccines can be dead or altered pathogens that stimulate immune cell memory with little to no risk of infection but might be too weak for an adequate response and require booster doses. “Live” vaccines utilize pathogens that are less virulent and reproduce very slowly, allowing the immune system to attack and produce memory cells for future application.
Without vaccinations, people would need to acquire the live, full-strength pathogen to develop defenses. Unfortunately, many infectious diseases are life-threatening. Even if the viruses or bacteria are not lethal to a large spectrum of the population they can still be deadly for vulnerable individuals like seniors. “The biggest issues are things like influenza in the older population and pneumococcus,” says Dr. Nikolich-Žugich.
The age at which function of the immune system decreases varies. Many factors can contribute to when and by how much. “If you look at various infectious diseases you can simply chart how frequent the severe forms of that disease are in a human population and at what ages. And there is an emerging consensus that sometime between forty and fifty most people are starting to show signs of measurable decline,” states Dr. Nikolich-Žugich.
Past and continued research has provided meaningful connections between immunity and detectable factors other than age. Some bacteria and viruses live forever in the human body, some good, some not so good. The cytomegalovirus (CMV) is a fairly common virus that many people have and the reason why it may be unfamiliar to most is because it generally lives within a person without creating symptoms. The virus can circulate and reactivate throughout the body. “The question is, when it activates, what is it doing when your immune system is good?” Dr. Nikolich-Žugich poses. Research has traced when the virus is active and it hopes to determine whether its presence is desired or dreaded, because there is evidence on both sides. “The helpful side is something that is a little more perplexing and fascinating and could we use it to improve the immune system through the action of that virus.”
Immune function may decrease as we age, but proactive preventive measures can help you to stay healthier. Being involved in your own health care is the first step, along with finding medical professionals who are equally invested in your well-being.
One such example is Iora Primary Care in Tucson, which has two locations both specializing in the care of seniors. One facility is on Grant and Alvernon. The other is on Broadway and Camino Seco where Miki Crane, M.D., is the medical director. Care at Iora is centered around patients who are 65 years old or older, and who have a Humana Medicare Advantage Plan. The medical office is designed to meet the needs of many seniors, with wide halls, carpetless floors and handrails on the walls. “Our main focus actually is on the patients themselves. We take the time to listen to what their concerns are and what it is they brought to the table for that particular appointment.”
At Iora, each patient’s care plan is individualized, but structured around a team-based approach. In addition to the doctor and nurse, the team may be composed of mental and behavioral specialists and health coaches. The team also can include family and caregivers to ensure a firm grasp on what needs to be accomplished to return the patient to health or to continue with a healthy life. “We include family members and caregivers to make sure we’re all on the same page and we’re understanding the plan. Otherwise the vulnerability of seniors is really scary, especially when they don’t have any support out there.” For the patients who may benefit from community outreach there are resources that Iora is able to connect them with, like the Pima Council on Aging. “Humana has case managers and social workers who may discuss patients who come up on our radar and we’re concerned about how they’re doing once they leave the clinic,” adds Dr. Crane.
One unique aspect of care at Iora is the inclusion of a health coach. Health coaches assist patients in lifestyle changes, ensure a crucial understanding of continued medical care and at the core are advocates for the patient. For patients with diabetes, a health coach can help adjust their diets. For patients with pain or stiffness, they can demonstrate safe exercises or stretches to alleviate pain or strengthen parts of the body. In addition, health coaches can recommend educational materials, like books or websites with pertinent information. Further still (under medical direction) they may uncover a cheaper alternative to current medications. Dr. Crane adds, “What a lot of our health coaches like to do is to help patients meet health goals. And what happens behind the scenes goes unnoticed and I think unrecognized, but they really are in charge of trying to get the referrals through that we need.”