Role of interleukin 6 and alpha-globulins in differentiating Alzheimer and vascular dementias.

BACKGROUND

Inflammatory mechanisms and immune activation have been hypothesized to play a role in the pathogenesis of age-associated diseases, including Alzheimer's disease.

PURPOSE

The evaluation of inflammatory markers in patients with dementia, and to determine whether these markers can be used to differentiate between vascular dementia (VD) and Alzheimer's dementia (AD).

PATIENTS AND METHODS

Twenty demented patients (10 AD and 10 VD) and 20 non-demented controls were subjected to clinical evaluation, MRI brain scans and laboratory tests, including interleukin (IL) 6, C-reactive protein and serum protein electrophoresis.

RESULTS

The results of this study revealed that serum levels of IL-6 and C-reactive protein were significantly elevated among patients with both types of dementia compared to normal elderly subjects. Although the mean IL-6 level was higher in patients with AD compared to patients with VD, this difference was not significant. The cutoff value at which the serum level of IL-6 gave maximum sensitivity and specificity was 14.25 pg/ml. Moreover, α₁- and α₂-globulins were able to discriminate between AD and VD (being significantly higher in AD).

CONCLUSION

IL-6 levels could be used to differentiate dementia from normal aging. Moreover, α₁- and α₂-globulins could differentiate between AD and VD. It can be concluded that inflammation plays an important role in both types of dementia.