One In Four Will Develop Symptomatic Hip Osteoarthritis By Age 85

Main Category: Arthritis / Rheumatology
Also Included In: Bones / Orthopedics;  Seniors / Aging
Article Date: 13 Nov 2006 - 0:00 PDT

email to a friend   printer friendly   opinions  

One in four persons. It is the first lifetime risk estimate for symptomatic hip osteoarthritis, and the risks are even higher for those who are overweight or obese, according to research presented this week at the American College of Rheumatology Annual Scientific Meeting in Washington, DC.

The pain, aching and stiffness of symptomatic hip osteoarthritis can lead to activity limitation and disability. Those with severe disease may undergo surgical hip replacement to reshape or replace the joint for easier movement and pain relief. These hip replacements, while common, are costly procedures. In 2004, approximately 226 thousand hip replacements were conducted in the United States at an estimated total cost of $8 billion.

These first lifetime risk estimates were derived from the Johnston County Osteoarthritis Project, a long-term study of knee and hip osteoarthritis conducted in North Carolina. Of the 3,068 individuals followed, ages 45 to 94, 18% were black and 57% female. Participants were evaluated for symptomatic hip osteoarthritis at the beginning of the study, and then again an average of six years later. Using these data to estimate the risk of developing symptomatic hip osteoarthritis by age 85, researchers found that women were at higher risk than men (28% as compared to 18%), whereas the risk for blacks and whites were similar (22% versus 25%). The risk of symptomatic hip osteoarthritis did differ by body mass index. Those of normal weight had a 20% risk compared with those who were overweight (25%) or obese (39%).

"Our results show another major public health problem associated with the aging population, one that may be aggravated by overweight and obesity," explains Dr. Louise Murphy, an epidemiologist with the Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, and lead investigator for the analysis. "However, weight management and physical activity are proven strategies in reducing pain associated with osteoarthritis, and disease self-management programs such as the Arthritis Self Help Course and the Chronic Disease Self Management Program may help people manage their arthritis."

Results of this study build on previous work by the CDC and the research team at the Thurston Arthritis Research Center, University of North Carolina Chapel Hill who previously reported the lifetime risk of symptomatic knee osteoarthritis to be one in two.

The American College of Rheumatology is the professional organization for rheumatologists and health professionals who share a dedication to healing, preventing disability and curing arthritis and related rheumatic and musculoskeletal diseases. For more information on the ACR's annual meeting, see http://www.rheumatology.org/annual.

Presentation Number: 1284

The Lifetime Risk of Symptomatic Hip Osteoarthritis is One in Four

Louise Murphy1, Charles G. Helmick1, Todd Schwartz2, Gail Tudor3, Gary Koch2, Jordan B. Renner2, Anca Dragomir2, William D. Kalsbeek2, Gheorghe Luta2, Joanne M. Jordan2. 1Centers for Disease Control and Prevention, Atlanta, GA; 2University of North Carolina, Chapel Hill, Chapel Hill, NC; 3Husson College, Bangor, ME Louise Murphy1, Charles G. Helmick1, Todd Schwartz2, Gail Tudor3, Gary Koch2, Jordan B. Renner2, Anca Dragomir2, William D. Kalsbeek2, Gheorghe Luta2, Joanne M. Jordan2. 1Centers for Disease Control and Prevention, Atlanta, GA; 2University of North Carolina, Chapel Hill, Chapel Hill, NC; 3Husson College, Bangor, ME

Purpose: The lifetime risk of symptomatic hip osteoarthritis (OA), a common indication for hip arthroplasty, is unknown. This study estimated the lifetime risk of symptomatic hip OA in Black and White men and women.

Methods: The study population was 3,069 participants of the Johnston County Osteoarthritis Project, a longitudinal population-based study in North Carolina. The mean age of the sample at baseline was 62 (range=45 to 94); 18% of participants were Black and 57% women. Symptomatic hip OA was defined as a Kellgren-Lawrence (K-L) radiographic score of ≥2 (from anterior-posterior pelvis x-rays), and report of pain, aching or stiffness on most days in the same hip. Estimates were generated for all cohort members (excluding women <50 years of age for whom hip radiographs were not obtained), and by sex, race, and body mass index (BMI). Lifetime risk was defined as the proportion developing symptomatic hip OA between ages 45 to 85, and was modeled using hip OA status at baseline and follow-up. Thus, lifetime risk is the probability of OA among those living to age 85. Logistic regression with repeated measures (through generalized estimating equations) was used to maximize use of OA data among persons with only baseline hip radiographs. Analyses, conducted in SUDAAN, including adjustment for the complex survey design of the study.

Results: The sex, race, and BMI adjusted lifetime risk of symptomatic hip OA was 24% (95% confidence interval [CI] =20-29). Lifetime risk increased with BMI, ranging from 18% (95% CI=12-24) among those of a normal weight to 38% (95% CI=28-48) among obese participants (test of difference, p<0.01). Women had an increased risk compared to men (26% versus 18%) whereas the risk was similar for Blacks and Whites (24% versus 21%); these differences were not statistically significantly different at alpha=0.05.

Conclusions: The lifetime risk of symptomatic hip OA was 24%, indicating that one in four people will develop symptomatic OA among those alive at age 85. Blacks are not spared the risk of symptomatic hip OA. Lifetime risk among obese participants was more than one in three. The prevalence of obesity in the United States is comparable to Johnston County, suggesting that the lifetime risk of at least mild symptomatic hip OA is also high in the United States population.

Disclosure Block: L. Murphy, None.

American College of Rheumatology (ACR)
1800 Century Place, Ste 250
Atlanta, GA 30345-4300
United States
http://www.rheumatology.org/

• Additional
• References
• Citations