How Much Weight Loss is Needed to Reduce Costs?

December 16th, 2014 by MorganDowney Leave a reply »

The whole premise of weight-focused employer wellness programs is that a significant amount of weight can be lost (by voluntary or involuntary participants) sufficient to reduce obesity-associated co-morbidities and, hence, health care costs, excessive sick days, etc. Unfortunately there is little to no evidence to support this premise.

Let’s just examine one part of this premise, namely, what is a sufficient weight loss to reduce costs. We have a systematic evidence review from the US Preventive Services Task Force which explored  behavioral counseling to promote a healthy lifestyle for cardiovascular disease prevention and found, “In general, intensive interventions that combined lifestyle interventions did not reduce CVD (cardio-vascular disease) events or mortality with up to 10 years of follow-up.” The researchers found “substantial statistical heterogeneity for weight outcomes” which is science-speak for ‘we can’t make heads or tails of the data’.

Now come three important studies. The first, from Tom Wadden and colleagues, looked at randomized controlled clinical trials that recruited overweight and obese subjects for primary care intervention, were provided with behavioral counseling (on diet, physical activity and behavioral therapy) for at least 3 months with at least 6 months of follow-up. They found that mean 6 month weight changes ranged from a loss of 0.3kg to 6.6kg. In the control group, mean change ranged from a gain of 0.9kg to a loss of 2.0kg. Weight loss in both groups declined with longer follow-up.

The second study from researchers in Canada looked at the assumption that a weight reduction of 5% to 10% was ‘clinically important.’ This is important because the economic arguments of employer weight wellness programs focus on achieving 5-10% weight loss. However, the employers do not realize that the great majority of health care costs are incurred by persons who have severe or morbid obesity.  What these researchers found was that the amount of weight loss needed by persons with severe obesity was markedly higher than what conventional (i.e. behavioral) therapy can deliver. In other words, rather than a weight loss of 5-10%, persons with severe obesity need a weight loss closer to 20% for clinicallly important improvements. This amount of weight loss can only be obtained using bariatric surgery. In other words, the type of interventions usually seen in employer wellness programs are insufficient to impact the higher costs associated persons with severe obesity.

The third study is from John Cawley and colleagues. They looked at the medical cost savings that can be achieved from a given amount of weight loss by people at different BMI values. They found that the savings from a given percent reduction in BMI are greater the heavier the individual with obesity and are greater for those with diabetes than those without diabetes. In other words, savings from a given BMI will be greater the higher the starting BMI. So the savings of a given amount of weight loss is going to be greater among persons with Class 3 obesity (BMI>40) and decline through Class 2 and Class 1.

The implications of these studies for employer wellness programs focusing on weight control is that they should be focused on the heaviest individuals and bariatric surgery should be provided for in the employer’s insured benefits. Wellness programs, properly structured, may provide useful, ancillary support but cannot alone reduce the higher costs associated with higher levels of obesity.