What extent of weight loss can benefit the health-related quality of life in motivated obese Chinese?

BACKGROUND A clinical significant improvement in health-related quality of life (HRQOL) is one of the main goals of weight control. OBJECTIVE To reveal the extent of weight loss on changes of HRQOL in obese Chinese. DESIGN A total of 119 motivated obese adults (BMI: 33.5 +/- 0.4 kg/m2) completed a 6-month weight loss intervention program by following either low calorie diet suggestions (LCDS; n=18), LCDS plus sibutramine (SG; n=27), LCDS plus orlistat (OG; n=41), or very low calorie diet (VLCD; n=33). Changes in body composition (TBF-410GS, Tanita Co., Tokyo, Japan) and HRQOL (36-item Short-Form (SF-36) questionnaire) were measured accordingly. RESULTS After 6-months, the greatest weight loss (p<0.001) was found in VLCD group (14.1 +/- 1.2 kg, 15.1%), followed by OG (10.6 +/- 0.9 kg, 11.5%), SG (9.6 +/- 1.3 kg, 10.2%) and LCDS alone (8.7 +/- 1.2 kg, 11.1%). The physical component score of SF-36 were significantly improved at 6-month follow-up (p<0.001), but not the mental component score. Improvements in general health score of SF-36 (Gamma mean: 6.1 +/- 2.8, p<0.05) were greater in females than males. Subjects with weight loss > or = 15 % had the greatest improvements in SF-36 scores whereas no changes in SF-36 scores were found with weight loss < 5%. CONCLUSIONS The extent, not the type of intervention, of weight loss is highly correlated with the favorable changes in HRQOL at 6-months. Weight loss above 5% of baseline values is necessary to show significant improvements in HRQOL in motivated obese Chinese.