Clinical trial NCT01469403: Weight Loss Intervention Before Total Knee Replacement
Official title: Weight Loss Intervention Before Total Knee Replacement, a Randomized Controlled Trial
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Osteoarthritis, Knee
Obesity
Keywords: Osteoarthritis, knee
Obesity
Weight Loss
Arthroplasty
Lead sponsor: University of Aarhus
Sponsor class: OTHER
Collaborators: name: The Danish Rheumatism Association
name: Cambridge Weight Plan Limited
First posted: 2011-11-10
Enrollment: 76
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: SUPPORTIVE_CARE

Brief summary: The purpose of this study is to compare the efficacy in a group of patients who must follow the current procedure for treatment of artificial knee, compared with a group of patients who must undergo an 8-week weight loss program before surgery. 1 year after surgery the investigators will examine whether there are differences between the two groups' quality of life and functional capacity.

Detailed description: Background In Denmark the numbers of primary total knee arthroplasty (TKA) operations annually increase. In the year 2000 was performed approximately 2,500 operations and in 2008 was performed more than 7,500 total knee arthroplasty operations, and there appears in all countries to be similar tendency. Meanwhile, the prevalence of overweight and obesity has increased markedly over the last 50 years. Approximately 13% of the Danish population is obese. For several years the association between obesity and knee osteoarthritis (OA) has been recognized, and osteoarthritis is the most frequent indication for total knee arthroplasty(80%).

The purpose of this study is to investigate whether weight loss interventions before primary total knee arthroplasty will improve quality of life and functional level, reduce pain and risk of early and late postoperative complications.

Sample size Significance level is set to 5% by using a 2-sided analysis and the power is set at 80%. Based on an expectation of a difference in patient-reported outcome scores in between the groups at 8%, as measured by SF-36 12 months postoperatively, standard deviation (SD) 13 must be include 41 participants in each group. To allow a drop-out rate of 20% the group size increases to 51 participants in each group. In total 102 participants.

Statistical analysis, The two groups scores at 12 months postoperatively, and the two groups' change in the primary outcome measurer, from 1 week before surgery to 12 months postoperatively, compared with t-test or Mann-Whitney test rang sum depending on data distribution.

Eligibility criteria: Inclusion Criteria:

* All patients recommended for primary total knee replacement.
* Body mass index \> 30.
* Must be motivated for weight loss.
* Must be able to read and understand Danish.

Exclusion Criteria:

* Rheumatoid arthritis.
* Patients who are operated on both knees during the project period can only participate once.
* Planned obesity surgery.

Primary outcomes:
measure: SF-36
timeFrame: Measured 12 months postoperatively.
Secondary outcomes:
measure: 6 minutes walk test (6MW).
timeFrame: Measured 1 week before surgery.
measure: Body composition
timeFrame: Measured 1 week before surgery.
measure: Bone mineral density (BMD).
timeFrame: Measured 12 months postoperatively.
measure: KOOS
timeFrame: Measured 1 week before surgery.
measure: Pain
timeFrame: Measured 1 week before surgery.
measure: Serum leptin.
timeFrame: Measured 1 week before surgery.
measure: Heart rate
timeFrame: Measured 1 week before surgery.
measure: Blood pressure
timeFrame: Measured 1 week before surgery.
measure: 6 minutes walk test (6MW).
timeFrame: Measured 8 week postoperatively.
measure: 6 minutes walk test (6MW).
timeFrame: Measured 12 months postoperatively
measure: Body composition
timeFrame: Measured 8 week postoperatively
measure: Body composition
timeFrame: Measured 12 months postoperatively
measure: KOOS
timeFrame: Measured 8 week postoperatively
measure: KOOS
timeFrame: Measured 12 months postoperatively
measure: Pain
timeFrame: Measured 8 week postoperatively
measure: Pain
timeFrame: Measured 12 months postoperatively
measure: Serum leptin.
timeFrame: Measured 8 week postoperatively
measure: Serum leptin.
timeFrame: Measured 12 months postoperatively
measure: Heart rate
timeFrame: Measured 8 week postoperatively
measure: Heart rate
timeFrame: Measured 12 months postoperatively
measure: Blood pressure
timeFrame: Measured 8 week postoperatively
measure: Blood pressure
timeFrame: Measured 12 months postoperatively
Other outcomes:
Locations:
city: Aarhus
country: Denmark
facility: Department of Orthopedics Research Aarhus University Hospital
Study officials:
affiliation: Department of Orthopedics Research Aarhus University Hospital
name: Kjeld Søballe, Prof. D.Msc
role: PRINCIPAL_INVESTIGATOR
References: