Effectiveness of Weight Control Program on Nutritional Status and Knee Pain in Overweight Older Adults

Purpose:  A common health problem in older adults is knee pain, particularly those with overweight. Weight control is an appropriate approach for overweight older adults suffering from knee pain. This study aimed to examine the effects of weight control program using community and group support on nutritional status and knee pain in overweight older adults with knee pain. The specific research purposes were to: 1) compare mean scores of nutritional status (body mass index and waist circumference) and knee pain in the experimental group before and after the program, and 2) compare mean differences of nutritional status (body mass index and waist circumference) and knee pain between the experimental and the control groups.

Methods: This study employed quasi-experimental research with 2-group pre-post design. Through convenience sampling with inclusion criteria, the sample included 60 overweight older adults with knee pain who lived in two communities in Bangkok, Thailand. The 30 subjects in the experimental group in a community participated in the 12-week weight control program including four stages: Raising community awareness, Aiming at target health outcome, Mobilizing change, and Assuring synergy through group activities. The program consisted of 14 activities addressing food exchange and behavioral modification for food consumption, arm swing exercise, knee exercise, modification of postures in daily living and arrangement of the surrounding environment in the community as well as monitor of body mass index and waist circumference. The control group received only leaflets and booklets. Data were analyzed using descriptive and inferential statistics including Chi-square test, Paired t-test, Independent t-test, and Wilcoxon Signed Ranks test.

Results:  Results revealed that the mean age of the subjects was 70.8 (SD 5.8) years, ranging from 60-84 years. There were no significant differences in demographic characteristics between the control and the experimental groups. At baseline, the mean body mass index, waist circumference, and knee pain in the control group were 27.2 kg/m² (SD 3.5), 94.6 cm (SD 9.5), 5.4 (SD 1.6), respectively and those in the experimental group were 27.9 kg/m² (SD 3.5), 95.3 cm (SD 8.8), 6.7 (SD 1.9), respectively. There were no significant differences in body mass index and waist circumference between the control and the experimental groups at baseline, except for knee pain. After the program, the experimental group had body mass index (27.2: SD 3.1), waist circumference (93.6: SD 8.7) and knee pain (4.4: SD 1.9) less than before the program with statistical significance (t = 2.128, p =.042; t = 6.599, p <.001; Z = -4.745, p <.001, respectively). Mean differences in body mass index (-.69), waist circumference (-1.74), and knee pain (-2.4) in the experimental group were more than differences in body mass index (.01), waist circumference (.44), and knee pain (.13) in the control group with statistical significance (t = 2.124, p =.038; t = 7.209, p <.001; t = 7.447, p <.001, respectively).

Conclusion:  The weight control program was effective. The results suggested approaches to behavioral modification on food consumption behaviors and group support for arm swing exercise and knee exercise as appropriate for the overweight older adults with knee pain.