APPLICATION OF AN INTENSIVE DIETARY REGIME IN REHABILITATION OF OVERWEIGHT PATIENTS WITH KNEE OSTEOARTHRITIS: A RANDOMISED CONTROLLED WEIGHT LOSS/SELF-MANAGEMENT TRIAL

L. Stigsgaard, R. Christensen , A. Astrup , H. Bliddal The Parker Institute, HS Frederiksberg Hospital, Dept. Human Nutrition, The Royal Vet. and Agricultural University, Copenhagen, DenmarkIt has been estimated that painful osteoarthritis (OA) in the knee joints affects 10% of the Western population older than 54 years, among whom 25% are severely disabled [1]. An increasing number of these patients will be overweight, which further necessitates intervention against the double jeopardy from the two diseases affecting the subject's locomotion. Accordingly, weight reduction strategies should be considered in overweight patients with knee OA. These considerations should include intensive vs. more moderate dietary interventions and the patients' ability to cope with the time-consuming intervention.Objective: To quantify the patients' self-reported satisfaction with the outcome of our 1-year intensive dietary rehabilitation program, built solely on dietary weight reduction strategies in a dietetic setting.Methods: 89 overweight (BMI> 28 kg/m) patients with knee OA according to the ACR-criteria were included and randomised to (intervention group) an intensive weight loss regime (36 visits; n=44) or (control group) a diet-related education on how to reduce body weight on their own (4 visits; n=45) during the first year of the trial [2]. The same dietician (LS) gave all diet-related instructions at group sessions. The intervention included teaching at group sessions and having the body weight measured individually in order to promote a decrease in fat intake and increase until 6 pieces of vegetables, fruit, and grain consumed in the six meals a day, as well as reducing the size of each helping by using the healthy eating plate model. In order to keep the motivation for changing eating habits, the patients in both groups were taught with motivational interviews and cognitive behaviour therapy besides practising appropriate grocery shopping and preparing meals according to the recommended diet with less fat and a high percentage of carbohydrates. For safety reasons, the dietician specifically did not advocate any increase in physical activity during the 1-year study period. The dietary goal was to achieve a weight reduction of at least 10% and the subsidiary outcome was the number of patients in each group feeling very satisfied with having participated in the study (score=5), using a 5 point likert-scale. The intention-to-treat (ITT) population (89 patients) was used in all analyses.Results: Most of the patients were females (89%), with an average age of 63, and a mean body weight corresponding to a class II obesity (BMI: 36 kg/m). In the intervention group 34 patients completed 1- year follow-up compared to 28 in the control group (P=0.12). Responders with a 10% weight loss in the intervention - and control group were: 54.5% and 8.9%, respectively (P<0.0001); corresponding to a Number Needed to Treat (NNT) of 2.2 (95% CI: 1.6 to 3.5) patients. A substantial benefit was reported from 56.8% in the intervention group compared to 15.6% in the control group, corresponding to a relative "risk" (RR) of being completely satisfied with participation in a 1-year self-management program; RR= 3.7 (1.8 to 7.6; P<0.0001). This number of completely satisfied patients corresponded to a NNT= 2.4 (1.7 to 4.3).Conclusion: We provide category 1b evidence that supports the use of a dietician for patients overweight with OA, as one of two ITT patients report that they are completely satisfied with following a 1-year intensive dietary program. These numbers indicate that tertiary prevention with dietary counselling might improve the self-reported disease status in 37,500 patients in the DK corresponding to 25% of the knee OA population over 54 years old.References: 1. Peat et al. Ann. Rheum. Dis. 2001;60:91-7.2. Christensen et al. Osteoarthritis. Cartilage. 2005;13:20-7.Citation: Ann Rheum Dis, volume 65, supplement II, year 2006, page 655Session: Evidence based practice in non-pharmacological treatment of osteoarthritis