A formula low-energy diet (LED) reduces weight effectively in obese patients with knee osteoarthritis, but the role of LED in long-term weight-loss maintenance is unclear.
Objective
We aimed to determine the effect of intermittent LED compared with daily meal replacements on weight-loss maintenance and number of knee replacements over 3 y.
Design
The design was a randomized trial with participants aged >50 y who had knee osteoarthritis and a body mass index [BMI (in kg/m2)] ≥30. Participants were recruited from the osteoarthritis outpatient clinic at Copenhagen University Hospital in Frederiksberg, Denmark; they had previously completed a 68-wk lifestyle intervention trial and achieved an average weight loss of 10.5 kg (10% of initial body weight). Participants were randomly assigned to either the intermittent treatment (IN) group with LED for 5 wk every 4 mo for 3 y or to daily meal replacements of 1–2 meals for 3 y [regular (RE) group]. Attention by dietitians and the amount of formula products were similar. Primary outcomes were changes in body weight and proportion of participants receiving knee replacements. Outcomes were analyzed on the intention-to-treat-population with the use of baseline-carried-forward imputation for missing data.
Results
A total of 153 participants (means ± SDs: BMI: 33.3 ± 4.6; age: 63.8 ± 6.3 y; 83% women) were recruited between June and December 2009 and randomly assigned to the IN (n = 76) or RE (n = 77) group. A total of 53 and 56 participants, respectively, completed the trial. Weight increased by 0.68 and 1.75 kg in the IN and RE groups, respectively (mean difference: −1.06 kg; 95% CI: −2.75, 0.63 kg; P = 0.22). Alloplasty rates were low and did not differ (IN group: 8 of 76 participants; RE group: 12 of 77 participants; P = 0.35).
Conclusions
After a mean 10% weight-loss and 1-y maintenance, additional use of daily meal replacements or intermittent LED resulted in weight-loss maintenance for 3 y. These results challenge the commonly held assumption that weight regain in the long term is inevitable. This trial was registered at clinicaltrials.gov as NCT00938808.
Key Words
weight loss maintenance
diet
obesity
knee osteoarthritis
low-energy diet
weight cycling
body composition
blood pressure
Abbreviations used
CAROT
Influence of Weight Loss or Exercise on Cartilage in Obese Knee Osteoarthritis Patients Trial
IN
intermittent treatment
KOA
knee osteoarthritis
KOOS
Knee Injury and Osteoarthritis Outcome Score
LED
low-energy diet
LIGHT
long-term intervention with weight loss in patients with concomitant obesity and knee osteoarthritis
MS
metabolic syndrome
RE
regular
SAE
serious adverse event
TKA
total knee alloplasty
Cited by (0)
Supported by grants from the Oak Foundation, Cambridge Weight Plan (United Kingdom), and the Danish Rheumatism Association. The Parker Institute receives financial support from public and private foundations, companies, and private individuals and is supported by a core grant from the Oak Foundation. This is a free access article, distributed under terms (http://www.nutrition.org/publications/guidelines-and-policies/license/) that permit unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
