June 25th, 2013

Silent Inflammation Linked to Macular Degeneration

Introduction:
Silent inflammation reflects an underlying low-grade stimulation of the inflammatory process with no outwards signs of inflammation. The only way that it is apparent is looking a blood levels for markers of inflammation like C-reactive protein. Silent inflammation is a major factor in the development of virtually every major chronic degenerative disease including cardiovascular disease, allergies, type 2 diabetes, cancer, and Alzheimer’s disease.

There are many factors that trigger silent inflammation including resistance to the hormone insulin, obesity, emotional stress, environmental toxins, low antioxidant intake or increased exposure to free radicals (e.g., radiation, smoking, etc.), chronic infections, imbalances of dietary fats, and increased intestinal permeability.

Background Data:
The most common test to measure silent inflammation is blood determination of C-reactive protein (CRP). Interest in measuring CRP as a marker of silent inflammation is the result of significant research showing it to be a very sensitive marker for the prediction for cardiovascular disease. Patients with high CRP concentrations are more likely to develop stroke, myocardial infarction, and severe peripheral vascular disease.

Research also indicates that elevations of CRP are linked to diabetes, some forms of cancer, Alzheimer’s disease, and many other chronic degenerative diseases including age-related macular degeneration – the major cause of blindness in North America.

The best determination is referred to as high-sensitivity CRP (hs-CRP).

New Data:
Pooled data from five very large studies provided significant evidence that elevated levels of hsCRP predict greater future risk of aging-related macular degeneration (AMD). After adjusting for cigarette smoking status, participants with high (>3 mg/l) compared with low (<1 mg/l) hsCRP levels had a 50% greater risk of developing AMD.

These results indicate another reason to include a hsCRP test as part of a yearly check up.

Comment:
There is little doubt that diet and lifestyle factors are the major contributors to silent inflammation and elevations in hsCRP. Here is a brief summary of important considerations:

Lifestyle Recommendations

  • Do not smoke.
  • Achieve ideal body weight.
  • Exercise on a regular basis.

Dietary Recommendations

  • Follow a low-glycemic, Mediterranean style diet.
  • Eat less saturated fat and cholesterol by reducing or eliminating the amounts of animal products in the diet.
  • Increase the consumption of fiber-rich plant foods (fruits, vegetables, grains, legumes, and raw nuts and seeds).
  • Increase the consumption of monounsaturated fats (e.g., nuts, seeds, and olive oil) and omega-3 fatty acids.

Key Nutritional Supplements

  • Fish oils: minimum 1,000 mg of EPA+DHA daily
  • Grape seed or pine bark extract (>95% procyanidolic oligomers): 100 to 300 mg daily

Reference:
Mitta VP, Christen WG, Glynn RJ, et al. C-reactive protein and the incidence of macular degeneration: pooled analysis of 5 cohorts. JAMA Ophthalmol. 2013 Apr;131(4):507-13.