For the 1.5 million Americans living with rheumatoid arthritis, recent research is worth watching.
Answers about the genetics of this autoimmune disease have been hard to come by. But by studying genetic variations, researchers in England have started to answer important questions: Can we predict the severity of rheumatoid arthritis? Can we predict how patients will respond to aggressive treatment?
There’s more work to be done. But there’s also reason to hope that genetic understanding of rheumatoid arthritis is coming.
“We want to be able to tell you, ‘Your symptoms will get better with aggressive therapy,’ or, ‘You probably won’t benefit from treatment, so you should avoid it — and skip the potential side effects.’ ”
Charis Eng, MD, PhD
Founding Chairwoman of the Genomic Medicine Institute
In this study, researchers examined data on several thousand patients. They looked specifically at a genetic variation called HLA-DRB1.
The researchers examined the association between HLA-DRB1 and the damage rheumatoid arthritis causes hands and feet. The results varied based on the location of HLA-DRB1. However, patients with this variation at one specific location had 1.75 times the risk of damage than those with no variation at all.
Researchers also analyzed how patients responded to tumor necrosis factor (TNF) inhibitor drugs. These medications — such as Enbrel, Simponi and Humira — treat the inflammation that comes with rheumatoid arthritis. In the study, patients with HLA-DRB1 variations responded better to the drugs.
Think of a number like “1.75 times the risk.” Compared to some of the other conditions we deal with in genetics, it’s fairly small. For comparison, someone with a BRCA1 mutation has an 80 percent lifetime risk of developing breast cancer.
But keep in mind that’s not an apples-to-apples comparison. When we study rheumatoid arthritis, we’re dealing with a genetic variation instead of a mutation. Think of a variation as a much smaller part of the larger whole that is mutation. In this case, the effects of a variation are much smaller than the effects of a mutation.
We also simply know more about mutations for diseases such as cancer. We have screening for BRCA genetic mutations. But we’re just now beginning to understand the way variations affect diseases like rheumatoid arthritis. The connection isn’t as strong, and the diagnostic tools are not ready for the public.
However, research such as this moves us closer.
This most recent research tells us we probably can predict who will have the most severe rheumatoid arthritis. It tells us we probably can predict who will respond best to treatment with TNF inhibitors. If future researchers produce similar results, clinical practice may change.
What would that mean for you, the patient? We want to be able to tell you, “Your symptoms will get better with aggressive therapy,” or, “You probably won’t benefit from treatment, so you should avoid it — and skip the potential side effects.”
Those are goals for the future. But if you’re a rheumatoid arthritis patient, there’s another message for now: If you’re willing, you can help advance the research needed to get to that future.
Ask your doctor if you are a candidate for clinical trials. These trials may be for assessing treatments or understanding genetic variations. The more research like this moves forward, the closer we are to answers for people with complicated chronic conditions.