Primary Care Corner with Geoffrey Modest MD: Longish-term followup of bariatric surgery

By: Dr. Geoffrey Modest 

JAMA published a systematic review in September of the long-term followup after bariatric surgery (see doi:10.1001/jama.2014.10706). Of all the studies, they found 29 which had clinical outcomes (type 2 diabetes, hypertension, hyperlipidemia), with at least 2 years of followup. 10 were RCTs. Longest follow-up was (only) 5 years. Results:

–Weight loss (> 50% of excess wt loss): in 31% of gastric band studies and 65.7% with gastric bypass, with mean % excess wt loss for gastric bypass = 65.7% (n=3544) and for gastric band = 45% (n=4109). 26 studies included

–Diabetes (achieving Hgb A1C < 6.5% without meds): gastric bypass = 66.7% (n=428) vs gastric band = 28.6% (n=96). six studies. mean decrease in A1c was 2.2% after gastric bypass and 1.5% after gastric band

–Hypertension (achieving BP<140/90 without meds): gastric bypass = 38.2% (N=808) vs gastric band =17.4% (n=247). 3 studies. 

–Hyperlipidemia (achieving chol<200, HDL>40, LDL <160 and TG <200): gastric bypass = 60.4% (n=477) vs gastric band = 22.7% (n=97). 3 studies. (none of the studies, however, reported use of lipid-lowering agents….)

–Insufficient data on gastric sleeve resections for long-term outcomes

–Complications: gastric bypass vs gastric band: death in 1% vs 0.2%

For gastric bypass:

–Incisional hernia, internal hernia, marginal ulcer in 1% each

–Anemia, Fe deficiency requiring transfusion or vit B12 deficiency in 2% each

–Re-operation for abdominal pain or nonhealing ulcer in 0.1% each

For gastric band:

–Port leak/revision 6%

–Band slip/obstruction 5%

–Treatment failure requiring revision 3%; band removal 2%

​–Erosion, esophagitis 1% each

So, the issues here are that obesity is a chronic disease, with likely benefit of identifying early and helping people from developing more severe obesity and its complications (and stressing the importance of public health initiatives to improve access to good/cheap food, exercise/safe neighborhoods, and generally promoting a more healthy lifestyle/curtailing the promotion of fast foods/junk foods, etc — FYI, there was a recent editorial promoting a tax on fast foods/junk foods to subsidize the rather expensive cost of fresh veges/fruits, for example). Bariatric surgery definitely has a place in the treatment of severe obesity (though I have seen some really dramatic results in some patients given the appropriate supports​, losing as much as with surgery). But one of the issues of bariatric surgery is that over time, people tend to gain weight, with one 8-year study finding treatment failure in 42% (which was probably closer to 50% with more intensive efforts to find those who dropped out of the study). in this context, it seems that in the longish term results here (limited by the max of 5 years noted), gastric bypass seems to get the best results (there are too few data on the gastric sleeve operations to comment).