An alternative to the CRP test is the “sedimentation rate” test, which measures how fast red blood cells settle and form a sediment. It is considered less sensitive than the hs-CRP test, but can be useful for some patients. Both tests, however, have a serious drawback: they are non-specific; that is, they simply detect inflammation from all sources, including medications or injuries. For this reason, they cannot always be used to measure “silent inflammation.” (For a list of symptoms commonly associated with chronic inflammation, see Symptoms of Silent Inflammation.) It is best to discuss these symptoms with your healthcare practitioner to determine if testing is appropriate for you.
Implications for Disease
For years, high levels of low-density lipoprotein (LDL) cholesterol were thought to be the best marker for future cardiovascular disease. However, a ground-breaking 2002 study, part of the Women’s Health Initiative, showed that people with high CRP levels were 4.5 times more likely to have a heart attack; this is much more predictive than LDL cholesterol or any other known measurement. In this study, which followed nearly 28,000 women for eight years, patients with the greatest risk of a heart attack were those with high levels of both CRP and LDL cholesterol. Women with the highest levels of CRP were almost 16 times more likely to develop diabetes.
In addition to predicting the onset of heart disease, elevated CRP levels correspond to a lower survival rate once these problems occur, according to Dr. Deron. High CRP levels exist in people who suffer recurrent heart attacks or angina. In his book, Dr. Deron notes that
CRP may not just be a marker for inflammation, it might be a cause. He cites a study that showed that CRP inflames arteries by triggering the formation of clots and plaque.
Other studies have found “silent inflammation” to be a significant risk factor for stroke and Alzheimer’s disease. In one study, those with the highest CRP levels were three times more likely to develop Alzheimer’s disease over a 20-year period. In patients with many forms of cancer, high levels of CRP correspond to a lower survival rate.
Gum disease and rheumatoid arthritis are among the inflammatory conditions that raise your risk of heart disease. Experts now believe inflammation may be the underlying reason. “Bear in mind that other well-established heart disease risk factors, such as obesity, lack of exercise, smoking, and high blood pressure, are all known to increase inflammation and CRP levels,” reminds Dr. Deron.
As mentioned earlier, obesity is also commonly associated with inflammatory conditions. In his article on how to lose weight by reducing inflammation, Dr. Perricone reports that scientists now regard body fat as an active endocrine organ. He explains that body fat produces hormones, including those that control our immune system and how much fat we store. Too much of certain hormones, such as cortisol or insulin, can put our bodies in a chronic state of insulin resistance—and low-level inflammation.
Hormones and Inflammation
Research into the interplay between inflammation and hormones is still in its infancy. In particular, sex hormones such as estrogens and progesterone appear to have important, but complex effects on the body’s inflammatory response. For example, many observers have wondered if the increase in inflammatory diseases that coincide with menopause, such as arthritis, might be related to shifts in the balance of progesterone and estrogens.
The complexity of hormonal effects on inflammation is evident in the scientific literature. For example, a literature review examining the role of estrogens in inflammation concluded that estrogens can either inflame or dampen inflammation, depending on a variety of factors, including the amount and composition of estrogens, the type of immune stimulus, the types of cells becoming inflamed, the presence of other hormones, and the presence of hormone receptors. A 2007 article published in Endocrine Reviews concurs that estrogens have both anti-inflammatory and pro-inflammatory roles and that estrogens do not function in the same manner in all inflammatory diseases, due to “the enormous variable responses of immune and repair systems.”
A 2003 study published in the Journal of the American College of Cardiology suggested two possible keys to this puzzle regarding estrogens’ effects on inflammation:
- The type of estrogen
- The route of administration
This study of 26 women, which compared the administration of two different types of estrogen, showed that oral conjugated equine estrogen pills (Premarin) doubled CRP levels and lowered levels of an anti-inflammatory growth factor (insulin-like growth factor-1 or IGF-1). Conversely, estradiol (Climara) delivered via a transdermal patch did not increase markers for inflammation. “Because CRP is a powerful predictor of an adverse prognosis in otherwise healthy postmenopausal women,” the authors concluded, “the route of administration may be an important consideration in minimizing the adverse effects of ET [estrogen therapy] on cardiovascular outcomes.”
A depletion of cortisol, the “stress” hormone, is also often implicated in furthering a pro-inflammatory state. Like insulin, cortisol is required for energy metabolism. It is also produced in large amounts in response to acute short-term stress, such as an infection. Thus, cortisol response must be adequate to handle short-term inflammation. After the stress and inflammation pass, the body’s “fight or flight” hormones quickly return to normal.
The problem with cortisol occurs when inflammation doesn’t stop. “Constant stress means constant secretion of cortisol,” Dr. Sears says. “As your body adapts to chronic stress, you become hyperinsulinemic, thereby creating more visceral fat. This fuels a new round of cortisol secretion, and the end result is you get fatter and wind up with chronic silent inflammation.”
Unfortunately, the body’s hormonal balance favors excess cortisol as we age, and counterbalancing levels of estrogens and testosterone drop. The resulting chronically high cortisol levels take a heavy toll on the body, from insulin resistance to reduced immune system function.
Excess cortisol is also associated with a low level of thyroid hormone, which typically results in difficulty losing weight, chronic infections, fatigue, and a wide variety of other conditions that may further compound the effects of inflammation.
Future research may unlock a clinical role for the adrenal hormone pregnenolone, the precursor to all steroid hormones in the body. Prior to the use of prescription cortisone in the 1950s, pregnenolone was used to treat arthritis after it was shown to be effective against joint swelling and inflammation. A study done in 1951 noted that those who responded to pregnenolone found the greatest benefit in recent lesions with the most visible inflammation. In his book, Pregnenolone: Nature’s Feel Good Hormone, Ray Sahelian, MD, wrote, “It remains to be seen how Preg[nenolone] can be effectively used in combination with other prescribed medicines and to alleviate the pain and other symptoms of rheumatoid arthritis.” He also noted that positive findings would permit lowering doses of non-steroidal anti-inflammatory drugs (NSAIDs), which cause serious side effects.
The Fix: Putting Out the Fire
For many people, the quick fix for their health concerns is over-the-counter or prescription medications. However, commonly used anti-inflammatory drugs such as NSAIDs and synthetic corticosteroids can have serious side effects. And, while a class of drugs called statins has demonstrated effectiveness in lowering both cholesterol and CRP levels, they also introduce the risk of serious side effects.
In search of better ways to “cool off” the body’s pro-inflammatory responses, many patients and practitioners are now looking beyond the medicine cabinet to the kitchen and the gym. Many practitioners now recommend that patients seeking to lower chronic inflammation start with a healthier lifestyle, specifically quitting smoking, and reforming their diet and workout habits. As a cardiologist, Dr. Deron promotes reducing inflammation as one way to prevent heart disease. His usual advice? Eating right, getting exercise, losing weight, and reducing stress.
Others concur that diet is key to putting out the burning ember within. For example, to counter the effects of triggers that are difficult to avoid, such as environmental allergies, Challem recommends dietary changes and nutritional supplements to help squelch the body’s inflammatory response and normalize the body’s immune response.
Dr. Sears provides a diet and exercise plan devised to stop the overproduction of hormones that fuel chronic inflammation. He recommends “anti-inflammatory” foods while stressing the need for moderation in the intake of protein, carbohydrates, and dietary fats. A typical “anti-inflammatory” diet seeks to amplify the body’s own anti-inflammatory substances. One such diet, espoused by Challem, separates foods into “hot” and “cold” groups. “Hot foods,” he says, set the stage for inflammation. They include:
- Most vegetable oils and food fried in them
- Margarine and most salad dressings
- Baked goods
- Many packaged foods
- Fast food meals
- Sugary beverages
Conversely, “cold” foods help douse inflammation, Challem says. He recommends consuming more:
- Olive oil
- Fish, particularly cold-water species
- Fresh vegetables
- Low-sugar fruits
- Free-range beef and chicken and game
- Mineral water
By replacing “hot” foods with “cold” ones, we boost our levels of anti-inflammatory vitamins, minerals, proteins, and omega-3 fatty acids, while reducing our levels of pro-inflammatory fats, says Challem. Moreover, an anti-inflammatory diet also reduces body fat and helps to curtail excess insulin levels, providing additional health benefits.