About Weight Loss Surgery Outcomes

Weight loss surgery is by far the most effective method available for long-term weight loss.* Patient outcomes, however, are not uniform between individual surgeons and programs. Some surgeons and programs achieve better outcomes than others.*

This variation in patient outcomes between surgeons and programs is significant.

To understand the significance of this variation, consider the following study by Ibrahim et al, published in 2017. The study authors compared the rate of serious complications after weight loss surgery at 165 accredited bariatric surgery center of excellence programs (145,527 total patients) nationwide. The study authors found that the rate of serious complications varied 17-fold (yes, 17-fold!) across the 165 center of excellence programs, from 0.6% to 10.3%.*
More about this study

Similarly, studies published by different surgeons report widely different average weight loss results, and widely different complication rates (e.g. leak rate, acid reflux rate) after both gastric sleeve and gastric bypass surgery, ranging from excellent to poor.*
Surgeon outcomes vary

Why is there so much variation in weight loss surgery outcomes between different surgeons and programs? Because of differences in surgical technique between surgeons (the operations are not standardized, so technique varies), and differences in patient care (education, follow-up, support).*
Why surgeon outcomes vary
The gastric sleeve operation is not standardized

Our Weight Loss Surgery Outcomes

Dr. Oliak’s #1 goal since starting his practice has been to achieve the best outcomes possible for his patients. By always prioritizing excellent surgery and patient care, Dr. Oliak has established a long record (>2500 operations since 2002) of weight loss surgery outcomes – weight loss results, complication statistics – that rank among the best in the weight loss surgery field.*
About our program

Gastric Sleeve Weight Loss

Dr. Oliak’s gastric sleeve patients average 75-80% EWL (excess weight loss) at 1-3 years after surgery. Several large review studies (e.g. Gagner et al) report overall average gastric sleeve weight loss to be approximately 60% EWL at 1-3 years after surgery.*
More about gastric sleeve
More about gastric sleeve weight loss

Gastric Sleeve Leak

The most feared complication after gastric sleeve surgery is leak. Dr. Oliak’s gastric sleeve leak rate is 0%.** Several large review studies (e.g. Aurora et al) have reported average leak rates to be in the 2-2.5% range.** Individual surgeon leak rates are reported to vary from 0-7%.**
More about gastric sleeve
More about gastric sleeve leak

Serious Complications

The Ibrahim et al study quoted above found that the 30-day serious complication rate after weight loss surgery varied between 0.6% and 10.3% across 165 different accredited bariatric surgery center of excellence programs nationwide. Using the same methodology and dates as in this study, Dr. Oliak’s serious complication rate is 0.6%.*
More about this study

Gastric Bypass Weight Loss

Dr. Oliak’s gastric bypass patients average 65% EWL (excess weight loss) at 10 years after surgery. The few good published studies on long-term gastric bypass weight loss (e.g. Pories et al) report an average of 55-60% EWL at 10+ years after surgery.*
More about gastric bypass
More about gastric bypass weight loss

* Patient results vary after weight loss surgery. The weight loss outcomes quoted on this page are averages – individual patients can lose more or less weight than the average.

** Leaks can occur after gastric sleeve surgery. Past leak rates may not be indicative of future leak rates. Dr. Oliak’s 0% leak rate statistic applies to primary (non-revision) sleeve gastrectomy and LAP-BAND® conversion to sleeve gastrectomy.

  • 0%
    gastric sleeve leak rate**
  • 76%
    excess weight loss 1 year after sleeve*
  • 65%
    excess weight loss 10 years after bypass*

Learn more about weight loss surgery and our program

Schedule a free, no-obligation consultation with Dr. Oliak in Orange County – Brea or Irvine – today!

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