Study Reveals a Link between Heart Disease and Knee OA

Severe knee osteoarthritis is modestly associated with an increased risk of all-cause and cardiovascular disease specific mortality, shows a study presented at the OARSI 2016 World Congress held in Amsterdam this month.

Individuals with cardiovascular disease (CVD) have increased odds of having knee osteoarthritis, as well as a higher likelihood of premature death. Study results suggested, however, other factors besides co-morbidities that could link osteoarthritis and mortality risk.

In an April 1 presentation titled, “Individuals with Severe Knee OA Are At Increased Risk of All-Cause and Cardiovascular Disease-Specific Mortality: The Johnston County Osteoarthritis Project,” Rebecca Cleveland, Ph.D., from the University of North Carolina at Chapel Hill, discussed how these associations were independent of comorbidities and socio-demographic measures linked to higher mortality.

Data on 4,403 participants, age 45 and older, in the Johnston County Osteoarthritis Project were analyzed to examine the association between baseline radiographic knee osteoarthritis measures and all-cause, cardiovascular disease-specific death. The original study enrollment included 3,185 individuals; an additional 1,218 joined as a cohort enrichment.

Researchers used the National Death Index date and cause-of-death records to assess vital status. They used the Kellgren-Lawrence (KL) grade of 2 in either knee to define knee ROA. Severe and symptomatic (sxOA) ROA received a KL grade 3. All models were adjusted for age, cohort (original or enrichment), gender, education, smoking, and self-reported high blood pressure, cancer, and diabetes, as well as heart disease and stroke.

Among participants, average age was 61, 63.5 percent were women, 35.2 percent were black, 36.1 percent didn’t complete high school, and 21.2 percent were smokers. Nearly 13.3 percent had diabetes, 10.1 percent had heart disease, slightly more than 1 percent had stroke and cancer each, and 39 percent had hypertension.

After follow-up at 14. 5 years, investigators determined that participants with knee radiographic osteoarthritis had significantly lower survival than those without it – 61.9 percent and 73.6 percent, respectively. After 24 years, severe, symptomatic knee osteoarthritis was modestly associated with an increased risk of all-cause and CVD-specific mortality.

“Our results suggest there may be mechanisms beyond comorbidities in the link between knee rOA and mortality risk that merit further investigation. Future studies should focus on potential interactions with comorbidities,” the authors wrote.

References:

R. J. Cleveland, T. A. Schwartz, et al. “Individuals with Severe Knee OA are at Increased Risk of All-Cause and Cardiovascular Disease-Specific Mortality: The Johnston County Osteoarthritis Project,” April 1, 2016. OARSI 2016.