Friday, January 17, 2014
Continuing in my discussion of the weight and health outcomes of the APPLES study, reported by Padwal and colleagues in Medical Care, we now turn our attention to the 150 participants who underwent bariatric surgery in a publicly funded bariatric program.
As noted in yesterday’s post, all surgical patients underwent intensive medical assessment and behavioural interventions prior to undergoing surgery. Thus, the outcomes reported in this group of participants is on top of any weight loss or benefits that patients may have experienced as a result of this intervention prior to surgery. It is thus, not surprising that at the time of enrolment to the APPLES study, surgical participants were approximately 4 Kg lighter than the “medical” participants (this being the average weight loss seen in the “medically” managed group).
Of the 150 surgical participants, 129 (86%) completed their 24 month visit. Data for the “drop-outs” was analysed as “last-observation-carried-forward”.
Overall weight loss at 24 months for the surgical group was 22 Kg (16.3%) with 75% achieving more than 5% weight loss, and 63% achieving more than 10% weight loss.
There were distinct differences in weight-loss outcomes between the different surgical procedures (all of which were performed in approximately equal proportions).
While the average weight-loss at 24 months for patients undergoing adjustable gastric banding was a paltry 7 Kg (5.8%), sleeve gastrectomy patients lost 21 Kg (16%), whereas bypass patients lost 37 Kg (26%) of their initial body weight.
All of these weight-losses were associated with marked improvements in cardiovascular risk factors.
There are several important learnings from this data.
1) Surgical treatments were markedly more effective than behavioural intervention (no surprise here).
2) There are significant differences in the amount of weight lost with the different surgical procedures, with bypass patients losing almost five times more weight that those undergoing gastric banding (rather unexpected).
3) Even with the greater weight loss achieved through surgical treatment, the average weight loss is still well under 30% of initial weight – again speaking to the refractoriness of severe obesity even with surgery.
Thus, despite its greater efficacy, even bariatric surgery will still leave many patients obese (based on BMI).
For clinicians (and patients) this means that many patients undergoing bariatric surgery, despite significant weight loss and considerable improvements in health and quality of life, may still be disappointed to not achieve their “ideal” or “dream” weight.
In the next post, I will summarize the overall learnings from this study and what they mean for the current status of bariatric care.
Padwal RS, Rueda-Clausen CF, Sharma AM, Agborsangaya CB, Klarenbach S, Birch DW, Karmali S, McCargar L, & Majumdar SR (2013). Weight Loss and Outcomes in Wait-listed, Medically Managed, and Surgically Treated Patients Enrolled in a Population-based Bariatric Program: Prospective Cohort Study. Medical care PMID: 24374423