In terms of cost, Weight Watchers was shown to be the least expensive intervention, consisting of an average annual cost of $377. The expected annual cost for Vtrim users was $682. Because of the relatively high cost of Jenny Craig food, it was the most expensive intervention, with an annual cost of more than $2,500.
Expected annual costs for the diet pills was $1,743 for Lorcaserin; $1,518 for Orlistat; and $1,336 for Qsymia.
Average weight loss at one year ranged from 2.4 kg (about 5 pounds) for Weight Watchers to 7.4 kg (16 pounds) for Jenny Craig. Those on Orlistat lost 2.8 kg (a little more than 6 pounds) whereas those on Vtrim and Lorcaserin both lost an average of 3.2 kg (about 7 pounds). Weight loss for those on Qsymia averaged 6.7kg (a little less than 15 pounds).
Based on the cost and weight-loss data, the average cost per kilogram lost ranged from $155 per kg for Weight Watchers to $338 or more for Jenny Craig. Qsymia came in at $232 per kg.
When the analysis was extended from cost per kilogram lost to cost per quality adjusted life year saved (QALY), the researchers found that Weight Watchers and Qsymia showed the best value for money. QALYs are often used to benchmark the value of a particular health innovation, with high value interventions typically improving QALYs at a rate of $50,000 or better.
"Health policy makers do not understand value in terms of cost per kilogram lost, but if you tell them that an intervention improves QALYs at better than $50K per QALY saved, they recognize that as good value for money," Finkelstein said.
For the remaining interventions, the additional weight loss came at a price higher than what third-party payers would be likely to cover without significant cost-sharing by participants.
"Although containing rising rates of obesity is a public health imperative, employers and third-party payers remain hesitant to sink big money into commercial weight
|Contact: Sarah Avery|
Duke University Medical Center