Session Information
Title: Osteoarthritis - Clinical Aspects I: Weight, Activity, and Metabolic Effects on Osteoarthritis
Session Type: Abstract Submissions (ACR)
Background/Purpose: Dietary induced weight loss is a proven non-pharmacologic intervention for osteoarthritis. Based upon current literature it is unclear if weight loss modifies structural progression. We report the radiographic and MRI structural outcomes of an 18 month study of intensive weight loss, with or without exercise compared to exercise alone in older, overweight and obese adults with symptomatic knee osteoarthritis.
Methods: The Intensive Diet and Exercise for Arthritis trial (IDEA) was a prospective, single-blind, randomized controlled trial that enrolled 454 overweight and obese (BMI = 27-42 kg/m2) older (age ≥ 55 yrs) adults with pain and radiographic evidence of tibiofemoral osteoarthritis (KL = 2-3). Participants were randomized to one of three 18-month interventions: intensive dietary weight loss-only (D); intensive dietary weight loss-plus-exercise (D+E); or exercise-only control (E). X-rays and MRIs were acquired at baseline and 18 months of follow-up. Standardized weight bearing x-rays (N = 325) were acquired and joint space width (JSW) was measured (blinded to time point) using an automated algorithm for minimum JSW and JSW at 4 fixed locations in the medial compartment. MRIs were obtained on a subsample of study participants (N = 105) and tibiofemoral cartilage thickness measured and semi-quantitative (SQ) MRI scoring performed using BLOKS. We used an intention to treat analysis to compare change between groups at 18 month follow-up. X-ray and MRI results were analyzed using ANCOVA adjusted for baseline values, BMI, and gender. X-ray was also adjusted for inter-rim distance. Ordinal logistic regression was used for the ordinal SQ analyses, adjusting for baseline values, BMI and gender.
Results: Mean baseline descriptive characteristics of the cohort included: age, 65.6 yrs.; BMI 33.6 kg/m2; 72% female; 81% white. A total of 399 (88%) participants completed the study and returned for FU18mth testing. Mean weight loss was: D, -9.5%; D+E, -11.4%; E, -2.2%. There were no baseline differences between groups in JSWx (0.225) 4.5 (1.9)mm or for cartilage thickness of the medial tibia and central medial femur combined 2.90 (0.08)mm. All 3 groups demonstrated continued progression of JSW loss with no significant difference between groups D -0.07(0.22)mm, D+E -0.27(0.22)mm and E -0.16(0.24)mm (p=0.79). All 3 groups demonstrated continued progression of MRI cartilage loss with no significant difference between groups D -0.10(0.05) mm, D+E -0.13(0.04)mm and E -0.05(0.04)mm (p=0.42). Maximal bone marrow lesion (BML) size showed a trend to improvement for the D+E OR 0.70 (0.25-1.95) and D OR 0.44 (0.16 – 1.23) groups.
Conclusion: Despite the potent effects of weight loss on symptoms, there does not appear to be any amelioration in the rate of structural progression either on x-ray or MRI cartilage measurement. The evidence of a trend towards improvements in BML suggests that this may be one mechanism for the symptom improvements related to weight loss.
Supported by grants from NIH R01 AR052528, P30 AG21332, M01 RR00211
Disclosure:
D. J. Hunter,
ARC Future Fellowship,
2,
DonJoy,
2,
NIH,
2,
NHMRC,
2;
D. Beavers,
None;
F. Eckstein,
Chondrometrics,
3;
A. Guermazi,
BICL, LLC,
4,
AstraZeneca, Genzyme, Novartis, and MerckSerono,
5;
R. F. Loeser,
None;
B. J. Nicklas,
None;
S. Mihalko,
None;
G. D. Miller,
None;
M. Lyles,
None;
P. DeVita,
None;
C. Legault,
None;
J. J. Carr,
None;
J. D. Williamson,
None;
S. P. Messier,
None.
ACR Meeting Abstracts - https://acrabstracts.org/abstract/the-intensive-diet-and-exercise-for-arthritis-trial-idea-18-month-radiographic-and-mri-outcomes/