Written by Rashelle Predovnik Thursday, 29 April 2010 12:33
SMOKING dramatically increases the risk of developing Rheumatoid arthritis in those genetically prone to the disease but researchers say exciting new treatments are in the pipeline.
The exact cause of Rheumatoid arthritis (RA) is not well understood but it is recognised that genetics, certain types of infections and environmental factors contribute to its development.
Currently, trials are underway in the Goatcher Clinical Research Unit at Royal Perth Hospital to refine existing treatments and administer them differently.
Clinical Associate Professor and Rheumatologist Dr Andrew Taylor says some of the treatments, yet to be released this year, are ‘pretty exciting’.
“In the last 10 years we’ve had these antibodies against tumour necrosis factor (TNF) and this year we’ll probably have two new ones coming out in addition to the three we already have.
“The other big agent that will be coming out this year also is a first in the treatment against Interleukin-6 (IL-6) which is another small molecule.
“So that works entirely differently from a different direction and has pretty significant and impressive benefits in patients.
“This agent is far more effective in treating a lot of the more systemic symptoms of RA such as anaemia, fatigue, fever and those types of aspects of the arthritis than the anti TNF agents so that’s one reason why it’s exciting.”
Dr Taylor also says it is also the first treatment shown to be effective without the use of methotrexate, an antimetabolite and antifolate drug used in the treatment of some cancers and autoimmune diseases.
Currently, RA is the second most common type of arthritis and the most common autoimmune disease in Australia.
According to Professor Peter Youssef, Rheumatologist at Royal Prince Alfred Hospital in Sydney, the greatest area of growth at the present moment is in the new biological agents for the treatment of rheumatoid arthritis.
However he says, it is important to recognise that studies have shown a significant link between the disease and smoking.
Professor Youssef says it is valuable to explain the risk of smoking because approximately 30 percent of the risk of developing rheumatoid arthritis is genetic and 70 percent is presumed to be environmental.
“We think that there are people who are genetically predisposed to RA and if they smoke they are more likely to get the disease, he says.
“The genes that increase the risk are HLADRB 0401 and 0404 and there are several other genes that may increase the susceptibility to RA in certain populations.
“Smoking leads to a change in the proteins in the joint lining called citrullination which then leads the body to produce anti CCP antibodies which may have a role in disease.
“Over the last few years it has become increasingly recognised that smoking increases the risk and the severity of disease in those patients who have the genetic predisposition and are anti-CCP antibody positive by about 20 times."
