Mysterious inflammation has impact

Conway McLean, DPM

The media certainly loves their buzzwords. And I hate to inflame the issue, but what is up with one of the most frequently used in popular publications? How many medical conditions, when referred to in newspapers and magazines, somehow utilize the term “inflammation”? Another common example, one of my favorites, is arthritis, which generally seems to refer to any pain, in any part of the body, be it an extremity, the back, etc. And when the arthritis word is used, you can bet they also make use of the inflammation word. It also gets thrown around routinely in many visits to your physician. So, what does it mean, and why is it so important?

Instinctively, most people think of inflammation as something bad, something to get rid of. We usually choose to medicate our pain or stiffness with drugs to relieve the discomfort. However, what you might not know is that inflammation is, in fact, a critically important part of our defense mechanism.

It is a normal part of the healing process. Inflammation is one of the body’s most important defense mechanism. Without it, we would not be able to fight bacterial infections, injuries, and destruction of tissues. So, how can inflammation be harmful since it is a naturally-occurring process in your body?

To some extent, inflammation is just a part of life, the inevitable cost of having an immune system. There’s probably always some inflammation going on somewhere in the body, and it even fluctuates in natural daily rhythms.

But most everyone recognizes the cardinal signs of inflammation: heat, redness, swelling, pain and loss of function. A good example of inflammation is when we get a splinter in our finger.

The redness seen with this trauma is caused by increased blood flow. The swelling is partly caused by white blood cells, dispatched by the immune system to destroy the attacker and repair the injury. Chemicals from these cells are released into the blood or affected tissues to protect your body from foreign substances (such as a splinter).

This release of chemicals increases the blood flow to the area of injury or infection, resulting in redness and warmth. Some of the chemicals cause a leak of fluid into the tissues, resulting in swelling. This protective process may stimulate nerves and so cause pain. These same signs can be observed in a sprained ankle, and with good reason. The pain and swelling limit use of the injured part, providing the body with the time for healing to occur.

What is the association between arthritis and inflammation? Osteoarthritis is considered a noninflammatory arthritis, but OA can still result in some inflammation of the joints. The difference is that this inflammation probably results from wear and tear. This is not the case with many types of arthritis such as rheumatoid arthritis, in which there is a misdirected attack by the body’s immune system.

The immune system triggers an inflammatory response when there are no foreign invaders to fight off. In these diseases, called autoimmune diseases, the body’s normally protective immune system causes damage to its own tissues. The body responds as if normal tissues are infected or somehow abnormal. An increase in the number of immune system cells and inflammatory substances within an arthritic joint will cause irritation, and swelling of the joint lining. Eventually, the cartilage will wear down, along with the destruction of various other components of the joint.

Many people think of inflammation in terms of the external signs mentioned earlier, such as swelling, redness, and so on. But in truth, uncontrolled inflammation plays a role in almost every major disease, including diabetes, cancer and heart disease. Even depression may be associated with higher levels of inflammation. So it’s easy to understand why inflammation is a hot research topic. Understanding exactly how it causes disease could lead to better interventions and treatments to stop abnormal inflammation.

If you’re on the far side of middle age, or you’re younger but struggling with your weight, or, perhaps, you have major long-term stressors in your life, chronic inflammation could be your issue. The science of obesity offers an example. We’re learning more about how obesity triggers a cascade of inflammation that leads to metabolic conditions such as insulin resistance, and eventually diabetes. Understanding exactly how that cascade works could lead to treatments for these conditions.

Cardiovascular disease was earlier thought to be a function of uncontrolled blood pressure, somehow combined with bad cholesterol levels. Yet, more and more, scientists believe inflammation may play a major role in cardiovascular disease. Will reducing inflammation lower the risk of heart disease? Signs of inflammation at the clogs which develop in our blood vessels have been observed for centuries. Although many risk factors have been identified and modified by preventive measures, coronary artery disease remains a common disorder. Despite extensive research, our understanding of the mechanisms behind coronary artery disease and the clotting of diseased arteries is incomplete.

But low-grade inflammation is not easy to detect or diagnose with blood tests. It may hide effectively in specific tissues and systems, only detectable with complicated, expensive, invasive testing. This is one of the main reasons that some diseases have been so mysterious for so long. How can vascular inflammation be measured and quantified? Which inflammatory mechanisms are most important when it comes to atherosclerosis and coronary artery disease? How can vascular inflammation be reduced or modified? Will measures that reduce inflammation affect the risk of atherosclerotic heart disease?

It is believed there are two different manifestations of inflammation: primary and chronic. The primary pathway works on detoxification and repair. This is a symptom-less pathway when it is efficient. Every day when you walk, exercise, eat or breathe, the body needs to cleanse and eliminate the build-up of toxins, and repair any cellular injury that has occurred. When primary inflammation is hard at work, you will not experience any pain or even be aware it is occurring.

When the primary pathway falls short, then the secondary pathway steps in. Secondary inflammation, or what you may know as chronic inflammation, is a pathway of protection. Unfortunately, when chronic inflammation remains for long periods of time and is not addressed adequately, it will cause the expression of genes that lead to degenerative conditions such as coronary artery disease, arthritis, cancer and others.

Scientists believe diet can have a profound effect on levels of chronic inflammation. Some studies have demonstrated a relationship between foods with a high glycemic index (simple sugars and carbs that are broken down quickly in the body) and chronic inflammation. Trans fats also seem to lead to higher levels. Foods with higher levels of omega-3, one of the essential fatty acids (meaning the body cannot manufacture it), are associated with lower inflammatory markers. The same can be said for a diet high in fruits and vegetables, also true for the Mediterranean diet (one that is based on the consumption of fish, legumes, vegetables, nuts, olive oil and wine).

Studies on inflammation, in its varied forms, continue. Much has yet to be discovered, but what we do know hints at an amazingly complex process, with good and bad consequences to our health and well-being. Dietary changes, along with exercise (also shown to lower inflammation when performed correctly) seem to be our best method of controlling this process, although medications do have their place.

Perhaps a better understanding of the development and manifestations of inflammation will lead to better control of various medical conditions, including such common ones as arthritis and heart disease. We can only hope that with time, and good medical studies, the truth about inflammation will be uncovered.

Editor’s note: Dr. Conway McLean is a podiatric physician now practicing foot and ankle medicine in the Upper Peninsula, having assumed the practice of Dr. Ken Tabor. McLean has lectured internationally on surgery and wound care, and is board certified in both, with a sub-specialty in foot orthotic therapy. Dr. McLean welcomes questions, comments and suggestions at drcmclean@penmed.com.