RA Bone Mineral Density Predicts Mortality

RA bone mineral density may be another indicator of the mostly hidden disease activity of rheumatoid disease (RD). Investigators studying patients in Texas have made some landmark observations.

RA bone mineral density may be associated with mortality

A session at the most recent scientific meeting of the American College of Rheumatology explored how RA bone mineral density is related to increased mortality in people with the disease. The session, “Low Appendicular Bone Mass Predicts Mortality in Patients with Rheumatoid Arthritis,” reviewed reduced lifespan in rheumatoid disease, most often due to cardiovascular causes. The authors suggested a meaningful association exists between osteoporosis and increased atherosclerosis of rheumatoid disease.

You might also like to read:

• Can Bones Hurt? Bone Pain and Rheumatoid Disease
• Nuclear Bone Scans for Rheumatoid Arthritis or Scintigraphy

Simple summary: RA bone mineral density as a significant indicator

The investigators studied 653 consecutive rheumatoid patients in San Antonio, Texas area, with average age 58, 72% of them women. They used “digital x-ray Radiogrammetry” (DXR) technology to calculate bone mineral density with digitized hand x-rays. DXR provides a “metacarpal index” (MCI) by a ratio of total bone width to cortical thickness. This MCI score quantifies peri-articular bone loss (bone loss near joints). DXR is more sensitive in detecting early RA bone mineral density loss than the DEXA (what is usually used, if bone mineral density is measured).

Then, they conducted a thorough investigation to learn of how many of the patients with rheumatoid disease (PRD) in the cohort had died.

Key points: Associations with RA bone mineral density (BMD)

1) Low BMD is independently associated with increased mortality in PRD*

2) Low DXR strongly associates with higher rheumatoid disease activity

3) Low DXR associates with significant joint destruction and may predict future joint destruction

4) The investigators concluded that BMD via DXR would be important to measure in rheumatology clinics.

5) Further research is needed to understand RA bone mineral density and mortality.

Bottom line: RA bone mineral density is part of a systemic disease

How can bone density be connected to mortality and heart disease in a “type of arthritis”? It can’t be.

Rheumatoid disease (RD) is obviously not a type of arthritis, but a systemic disease that affects all of the body. The same wasting disease that is destroying joint and bone tissue is wreaking havoc in other body organs and systems. Unfortunately, this is why RD increases mortality. Some aspect of the disease is responsible for both cardiovascular disease and lowered BMD.

It’s reading thousands of studies like this one over the past 12 years that finally led me to publish a book to try to open eyes—and save lives. The connections between the systemic aspects of RD and the better-known joint symptoms are not in my imagination. Investigators are exploring their significance. And sometimes they suggest ways to mitigate risks for people—in this case measuring RA bone mineral density.

Living with a “bone eating” invisible illness

I know what it feels like to have most of your illness to be invisible. To have people assume you’re fine—even when you try to explain how the disease affects you. Low bone mineral density is one more invisible aspect of a cruel destructive disease. Honestly I so much wished for a t-shirt that said THIS is what invisible illness looks like that I designed some. And then I bought a few. And I’ve been wearing them often.

WHAT’S YOUR EXPERIENCE WITH INVISIBLE ILLNESS SYMPTOMS? HAVE YOU MEASURED RA BONE MINERAL DENSITY?

Recommended reading

• Ultrasound for Seeing Invisible Inflammation in Rheumatoid Patients
• 5 RA Facts Everyone Needs to Know
• What Causes Rheumatoid Arthritis Pain?

Click to read the online summary of this ACR session, “Low Appendicular Bone Mass Predicts Mortality in Patients with Rheumatoid Arthritis.”

* Low BMD is independently associated because other factors were adjusted for including age, sex, ethnicity, cardiovascular risk factors, measures of RA disease in joints, and joint damage.