Session Information
Session Type: ACR Poster Session B
Session Time: 9:00AM-11:00AM
Background/Purpose: To describe the prevalence and risk factors of patellofemoral osteoarthritis (OA) in a Chinese population.
Methods: A multi-center population-based cross-sectional survey was conducted in 2015 in Beijing, Henan and Ningxia, China. 4138 residents aged &ge50 years were recruited using a cluster sampling method. Subjects completed a home interview (including socio-demographic factors, history of knee injury, joint symptoms, job-related physical activity and work history) and had weight-bearing posterior-anterior semi-flexed view of radiographs at tibiofemoral joints and skyline view of radiographs at patellofemoral joints (PF). Height was measured twice for each subject, using a wall-mounted studio meter and weight was assessed using a balance beam scale with a precision to 0.1 kg. BMI was calculated as weight in kilograms divided by height in meters squared. Radiographs were read by two orthopedic surgeons. Each knee was evaluated for the presence of osteophytes (OST), joint space narrowing (JSN) on a 0-3 scale based on OARSI atlas. If two readers disagreed on a patient’s OA status, adjudication session was held with third orthopedic surgeon present. Radiographic OA (ROA) at PF joint was defined if OST score was &ge2 or if JSN score was &ge2 with concurrent grade 1 OST in the PF joint. The kappa for inter-rater reliability was 0.71-0.85 and the intra-rater reliability was 0.85-0.91 prior to adjudication. Knee pain symptoms were asked for each participant using the following questions &Prime Did knee pain occur when going up and down stairs on most days in the past month? &Prime PF symptomatic OA (SxOA) was recorded if both pain and ROA were present at the same knee. We examined the relations of a set of risk factors to the prevalence of PF ROA and SxOA using logistic regression model.
Results: Of 4138 subjects recruited, 533 (12.9%) subjects were excluded from the analysis due to missing knee radiographs. Of the remaining (n=3605) 35.6% (n=1283) were men, mean age was 62.89±7.58 years, and mean BMI was 25.05±3.60 kg/m2; 64.4% (n=2322) were women, mean age was 60.86±7.50 years, and mean BMI was 26.26±3.81 kg/m2. The prevalence of PF ROA and SxOA was 23.7% and 14.1%, respectively. As shown in Table 1, women, older age, higher BMI, history of knee injury and bicycling &ge2 hours per day lasted less than 30 years were significantly associated with both PF ROA and SxOA. Few years of education was associated with high prevalence of PF ROA, whereas standing &ge2 hours per day lasted less than 30 years was associated with PF SxOA. No statistical significant difference was observed between job-related physical activity and PF ROA/SxOA.
Conclusion: Our study suggests that prevalence of PF ROA and SxOA was high in China. Several potential risk factors for prevalent PF OA were identified and need to be verified in the future prospective cohort studies.
Table 1. Association between risk factor with PF ROA/SxOA
|
Potential risk factors |
Level |
Radiographic patellofemoral OA |
Symptomatic patellofemoral OA |
||
|
|
OR (95% CI)
|
P-value |
OR (95% CI)
|
P-value |
|
|
Sex |
|
1.23 (1.01,1.49) |
0.034
|
1.33 (1.06,1.67) |
0.015
|
|
Education |
|
0.80 (0.66,0.97) |
0.026
|
0.82 (0.65,1.05) |
0.113 |
|
Age |
|
1.06 (1.04,1.07) |
<0.001
|
1.06 (1.05,1.08) |
<0.001
|
|
BMI |
|
1.12 (1.10,1.15) |
<0.001
|
1.12 (1.09,1.15) |
<0.001
|
|
History of knee injury |
No |
|
|
|
|
|
Yes |
1.38 (1.04, 1.83) |
0.026
|
1.74 (1.28, 2.39) |
0.001
|
|
|
Duration of physical activity at work, year
|
|
|
|||
|
Standing &ge2 hours per day |
0 |
1.0 |
|
1.0 |
|
|
1-29 |
1.12 (0.87,1.44) |
0.396 |
1.33 (1.00,1.77) |
0.048
|
|
|
30+ |
0.86 (0.61,1.21) |
0.387 |
0.99 (0.71,1.37) |
0.942 |
|
|
Walking &ge2 hours per day |
0 |
1.0
|
|
1.0
|
|
|
1-29 |
1.05 (0.81,1.35) |
0.131 |
0.94 (0.69,1.29) |
0.712 |
|
|
30+ |
0.91 (0.64,1.30) |
0.298 |
0.79 (0.52,1.21) |
0.284 |
|
|
Bicycling &ge2 hours per day |
0 |
1.0 |
|
1.0 |
|
|
1-29 |
1.33 (1.01,1.74) |
0.042
|
1.43 (1.04,1.97) |
0.027
|
|
|
30+ |
1.16 (0.84,1.61) |
0.358 |
1.38 (0.71,1.37) |
0.915 |
|
|
Bending &ge2 hours per day |
0 |
1.0 |
|
1.0 |
|
|
1-29 |
1.06 (0.81,1.40) |
0.651 |
1.26 (0.81,1.94) |
0.309 |
|
|
30+ |
1.04 (0.71,1.53) |
0.825 |
1.04 (0.71,1.52) |
0.837 |
|
|
Squatting &ge30 minutes per day |
0 |
1.0 |
|
1.0 |
|
|
1-29 |
1.17 (0.74,1.56) |
0.699 |
1.17 (0.87,1.57) |
0.308 |
|
|
30+ |
1.08 (0.40,1.10) |
0.113 |
1.28 (0.85,1.94) |
0.232 |
|
|
Lifting &ge10kg object per day |
0 |
1.0 |
|
1.0 |
|
|
1-29 |
1.20 (0.95,1.53) |
0.133 |
1.23 (0.92,1.65) |
0.169 |
|
|
30+ |
1.17 (0.74,1.84) |
0.497 |
1.36 (0.82,2.23) |
0.230 |
|
|
Climbing &ge2 hours per day |
0 |
1.0 |
|
1.0 |
|
|
1-29 |
1.39 (0.75,2.60) |
0.300 |
1.21 (0.56,2.58) |
0.630 |
|
|
30+ |
0.83 (0.37,1.86) |
0.826 |
1.29 (0.52,3.20) |
0.582 |
|
To cite this abstract in AMA style:
Li Z, Liu Q, Zhao C, Zhang Y, Li X, Lin J. The Prevalence of Patellofemoral Osteoarthritis in China: A Multi-Center Population-Based Cross-Sectional Study [abstract]. Arthritis Rheumatol. 2017; 69 (suppl 10). https://acrabstracts.org/abstract/the-prevalence-of-patellofemoral-osteoarthritis-in-china-a-multi-center-population-based-cross-sectional-study/. Accessed .« Back to 2017 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/the-prevalence-of-patellofemoral-osteoarthritis-in-china-a-multi-center-population-based-cross-sectional-study/