TEN PERCENT OR GREATER WEIGHT LOSS IS A CLINICALLY MEANINGFUL OUTCOME IN THE TREATMENT OF OBESITY

Purpose: Health plans vary widely in their coverage and reimbursement policies for obesity treatments, in part due to a lack of consensus about the degree of weight loss that will confer obesity-related morbidity risk reduction.  Although a weight loss of 5-10% has been associated with clinical benefits, NIH obesity guidelines state that the goal of obesity treatment should be a loss of at 10% or greater of baseline weight.  This review examines the literature on weight loss and associated clinical outcomes to determine whether a 10% weight loss threshold should be considered clinically meaningful.

Method: We examined the long-term effects (minimum study duration 2 years) of 10% intentional weight loss among overweight and obese adults on obesity-related health outcomes, including hypertension, type 2 diabetes mellitus (T2DM), and hyperlipidemia.  Relevant studies were identified through a Medline search of English studies [Medical Subject Headings: Obesity" AND ("Weight Loss" OR "Body Weight Changes") AND ("Heart Diseases" OR "Hypertension" OR "Blood Pressure" OR "Diabetes Mellitus, Type 2" OR "Glucose Metabolism Disorders" OR "Insulin Resistance" OR "Hyperlipidemias")].

Result: Among 1,292 citations, 104 were identified as relevant.  Weight loss of 10% is associated with improved blood pressure and glycemic and lipid outcomes.  With respect to hypertension, a weight loss of 10% appears to be required to resolve hypertension among overweight/obese persons.  For glycemic outcomes, a weight loss of 10% or more is associated with a 1.6% decrease in hemoglobin A1c, a 63% reduction in diabetes medication use, and 33% reduction in mortality among overweight and obese persons with T2DM.  A sustained weight loss of 16% reduces the 8-year incidence of T2DM by >80% in severely obese persons.  Weight loss of 10% improves hyperlipidemia, especially among those with high baseline cholesterol levels who are able to maintain their weight loss.

Conclusion: Weight loss of ≥10% confers substantial cardiovascular and metabolic benefits among overweight and obese adults, and appears to be a more clinically significant intermediate marker of the effectiveness of weight loss interventions.  Consistent application of this benchmark by health plans in determining coverage and reimbursement for weight loss interventions may result in wider access to more effective treatments and reduce the escalating rate of obesity-related diseases and related spiraling medical costs.