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Multicenter Study
. 2014 Mar;22(3):431-9.
doi: 10.1016/j.joca.2013.12.018. Epub 2014 Jan 11.

Body mass index is not a clinically meaningful predictor of patient reported outcomes of primary hip replacement surgery: prospective cohort study

A Judge  1 , R N Batra  2 , G E Thomas  3 , D Beard  4 , M K Javaid  5 , D W Murray  6 , P A Dieppe  7 , K E Dreinhoefer  8 , K Peter-Guenther  9 , R Field  10 , C Cooper  11 , N K Arden  12
Affiliations
Multicenter Study

Body mass index is not a clinically meaningful predictor of patient reported outcomes of primary hip replacement surgery: prospective cohort study

A Judge et al. Osteoarthritis Cartilage. 2014 Mar.

Abstract

Objectives: To describe whether body mass index (BMI) is a clinically meaningful predictor of patient reported outcomes following primary total hip replacement (THR) surgery.

Design: Combined data from prospective cohort studies. We obtained information from four cohorts of patients receiving primary THR for osteoarthritis: Exeter Primary Outcomes Study (EPOS) (n = 1431); EUROHIP (n = 1327); Elective Orthopaedic Centre (n = 2832); and St. Helier (n = 787). The exposure of interest was pre-operative BMI. Confounding variables included: age, sex, SF-36 mental health, comorbidities, fixed flexion, analgesic use, college education, OA in other joints, expectation of less pain, radiographic K&L grade, ASA grade, years of hip pain. The primary outcome was the Oxford Hip Score (OHS). Regression models describe the association of BMI on outcome adjusting for all confounders.

Results: For a 5-unit increase in BMI, the attained 12-month OHS decreases by 0.78 points 95%CI (0.27-1.28), P-value 0.001. Compared to people of normal BMI (20-25), those in the obese class II (BMI 35-40) would have a 12-month OHS that is 2.34 points lower. Although statistically significant this effect is small and not clinically meaningful in contrast to the substantial change in OHS seen across all BMI groupings. In obese class II patients achieved a 22.2 point change in OHS following surgery.

Conclusions: Patients achieved substantial change in OHS after THR across all BMI categories, which greatly outweighs the small difference in attained post-operative score. The findings suggest BMI should not present a barrier to access THR in terms of PROMs.

Keywords: Body mass index; Decision making; Epidemiology; Hip replacement; Osteoarthritis; Patient reported outcome.

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Figures

FIGURE 1
FIGURE 1. Results of Fixed-effects meta-analysis
FIGURE 2
FIGURE 2. Change on Oxford Hip Score between baseline and 12-months follow up, stratified by body mass index categories
See this image and copyright information in PMC

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References

    1. Harris WH, Sledge CB. Total Hip and Total Knee Replacement (1) N Engl J Med. 1990;323:725–31. - PubMed
    1. Harris WH, Sledge CB. Total Hip and Total Knee Replacement (2) N Engl J Med. 1990;323:801–07. - PubMed
    1. Ethgen O, Bruyere O, Richy F, Dardennes C, Reginster JY. Health-Related Quality of Life in Total Hip and Total Knee Arthroplasty. A Qualitative and Systematic Review of the Literature. J Bone Joint Surg Am. 2004;86:963–74. - PubMed
    1. Culliford DJ, Maskell J, Kiran A, Judge A, Javaid MK, Cooper C, et al. The lifetime risk of total hip and knee arthroplasty: results from the UK general practice research database. Osteoarthritis Cartilage. 2012;20:519–24. - PubMed
    1. Arden NK, Kiran A, Judge A, Biant LC, Javaid MK, Murray DW, et al. What is a good patient reported outcome after total hip replacement? Osteoarthritis Cartilage. 2011;19:155–62. - PubMed

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