Three out of five TNF blockers tested were found to reduce the risk of Alzheimer's disease in Rheumatoid arthritis patients, a study said.

This research was conducted by Richard C. Chou, MD, PhD, of Dartmouth Medical School in Lebanon, N.H. and findings presented in a medical conference and at annual meeting of the American College of Rheumatology.

TNF blockers act by neutralizing the tumor necrosis factor alpha (TNF) protein that is over produced during inflammations in rheumatoid arthritis. In case of Alzheimer's, TNF levels were found to be elevated and are related to disease progression. "Studies have shown that TNF is also elevated in the cerebrospinal fluid of Alzheimer's patients and that higher levels correlate with the progression of the disease," Cho mentioned.

A massive 8.5 million US patients were screened from the medical and pharmacy claims database and 165 people with both RA and Alzheimer's disease were short-listed. These individuals were compared in a 1:10 ratio with arthritis-only patients belonging to same age, sex and treatment period. The study then accounted for Alzheimer's risk factors namely high cholesterol and diabetes. With TNF blockers, RA patients showed 55% lower risk of Alzheimer's. It is important to bear in mind that this study is not a cause and effect analysis but only provides for link by association.

3 of 5 blockers, namely Enbrel, Humira, and Remicade were tested. Cimzia and Simponi were omitted from the study for reasons not given. As expected, testing non TNF blockers, Azulfidine, prednisone, and Rituxan had no effect on the risk of Alzheimer's disease.

Enbrel being the smallest of the 3 TNF blockers can cross the blood-brain barrier easily. This drug reduces the risk of Alzheimer's by 70%. This is highly encouraging news because scientists have long been trying to identify drugs that target brain cells of Alzheimer's patients known to accumulate destructive plaques and tangles. Reducing inflammation in RA is beneficial for an Alzheimer's patient’s brain.