2017 ISAKOS Biennial Congress ePoster #603
Maximum Lifetime Body-Mass-Index Is A Good Predictor For Knee And Hip Osteoarthritis
Dietmar Dammerer, Prof. Dr.med.univ., MSc, PhD, Krems AUSTRIA
Sabine Patricia Singer, MD,, Munich GERMANY
Dennis C. Huber, Mag. rer. nat., Innsbruck AUSTRIA
Ingrid Singer, MD, MSc, Vienna AUSTRIA
Martin Krismer, Prof., Grinzens, Tyrol AUSTRIA
Wolfgang Hackl, MD, Innsbruck AUSTRIA
Michael C. Liebensteiner, MD, PhD, Innsbruck, Tyrol AUSTRIA
Medical University of Innsbruck, Dept. of Orthopedics, Innsbruck, AUSTRIA
FDA Status Not Applicable
Summary
The maximum Body-Mass-Index over one’s lifespan is a better predictor of osteoarthritis of the hip or the knee than the current Body-Mass-Index. The knee joint seems to be more sensitive to obesity than the hip.
Abstract
Purpose
Due to inconsistencies in the literature, it was the aim of the study to investigate the relationship between obesity (current and historic) and osteoarthritis (OA) of the knee or hip. It was hypothesized that there would be a significant association between the ‘maximum-BMI-over-one’s-lifespan’ (‘maximum-BMI’) and OA of the knee or hip
Hypothesis
1). It was further hypothesized that the ‘current BMI’ would be linked to OA of the knee and hip
Hypothesis
2). Further associations were tested on an explorative basis.
Methods
We examined 99 people (knee OA, hip OA and controls), age > 50 years, in a case control study. The current weight, height and waist circumference were measured on site, and detailed weight changes over their lifetime were based on questionnaires and standardized interviews. We used binomial logistic regression to determine the predictive value for an osteoarthritis group membership of each derived indicator.
Results
An increase in ‘maximum-BMI’, increased the odds ratio for both knee OA (OR 1.2; CI 1.1 - 1.4; p=0.005; R²= 0.36) and hip OA (OR 1.2; CI 1.0 - 1.3; p= 0.027; R²= 0.16)
Hypothesis
1). Current BMI was significantly associated with knee OA but not with hip OA.
Hypothesis
2).
Further, explorative data analysis revealed the following: When comparing the knee OA to the hip OA group directly, the waist indicators showed a significant association with knee OA: the ‘waist-to-height-ratio’ (OR 1.1; CI 1.0 – 1.2; p= 0.032; R²= 0.38) showed a similar predictive value as the ‘waist-circumference’ alone (OR 1.1; CI 1.0 - 1.1; p= 0.038; R²= 0.36).
A high “minimum-BMI” (over the age of 18 years) had the highest odds ratio of all calculated indicators for both osteoarthritis groups.
Conclusion
Based on our findings it is concluded that the maximum BMI over one’s lifespan is a better predictor of OA of the hip or the knee than the current BMI. These findings support the use of the most sustainable methods of weight control. The knee joint seems to be more sensitive to obesity as current BMI was associated only with knee OA but not with hip OA.