Race, Clinical Factors Predict Weight Gain After Roux-en-Y

— African Americans, nonusers of pharmacotherapy more likely to experience regain

MedicalToday

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NASHVILLE, Tenn. -- Certain factors may be tied to weight recidivism following Roux-en-Y gastric bypass surgery, researchers reported here.

In a review of 1,395 patients who underwent this type of bariatric surgery at a U.S. medical center, African American patients saw the highest average weight regain in the 11 years after surgery, Dylan Thomas, MD, of Boston University School of Medicine, and colleagues wrote in :

  • African Americans: 22.4% regain relative to weight loss ± 1.9
  • Hispanics: 17.2% ± 2.6
  • Caucasians: 13.5% ± 1.5

African American individuals also had a significantly higher average maximal weight regain of 12.7 kg (28.0 lb) compared with 8.6 kg (19.0 lb) for Hispanic and 8.7 kg (19.2 lb) for Caucasian patients, and saw the lowest average percentages of total weight loss following surgery (30.3% of baseline ± 0.7, 32.5% ± 0.9, 32.9% ± 0.5, respectively).

"Many of the existing studies of weight regain after bariatric surgery included data on only a couple of years after surgery, so the long-term patterns of weight regain were not well known," Thomas explained to , adding how at his institution, weight recidivism is a clinically relevant and significant problem.

"Our previous studies showed that African Americans tend to lose less weight after [Roux-en-Y gastric bypass] than Caucasians and may have different clinical outcomes," he said. "Thus, identifying predictors of weight regain in our population and investigating whether there are racial differences was a logical extension of our earlier studies."

He added that his group found it particularly surprising that both African American and Hispanic individuals had significantly more weight regain compared with Caucasian patients.

"This has not been previously reported to our knowledge," he said, but noted that quite a bit of literature has suggested that obesity and metabolic disease as a whole may be phenotypically different in African American patients. "This study adds to this existing literature by documenting subtle differences in the long-term weight trajectory following weight loss surgery."

The review looked at electronic medical records of African American, Hispanic, and Caucasian adults who underwent Roux-en-Y gastric bypass from 2004 to 2015. Weight regain was defined as the difference in weight at the most recent follow-up compared to nadir weight achieved between 12 to 16 months after surgery.

"There are a number of potentially modifiable factors that contribute to weight regain that should be optimized in patients after [Roux-en-Y gastric bypass] including mental health, eating behaviors, physical activity," Thomas suggested, also listing other factors affecting regain risk -- age, maximum weight loss following surgery, pre-operative weight, socioeconomic status, and race.

"More studies are also needed to develop strategies to prevent and treat weight regain," he stated.

In an attempt to tackle this additional research question, Thomas's group conducted a of this retrospective review, which found post-operative adherence to weight loss medication among this cohort was able to significantly reduce the risk of weight regain. Thomas presented these findings at ObesityWeek, a joint meeting of the Obesity Society and the American Society for Metabolic and Bariatric Surgery.

For this analysis, 1,326 of the individuals from the initial cohort were included. These patients were divided into two categories based upon adherence to prescribed weight loss medication and follow-up visits and those who did not adhere to follow-up plans.

Over the 11-year follow-up period, patients who adhered to weight loss medications after Roux-en-Y gastric bypass had a 28% lower risk for weight regain compared with patients who did not use weight loss medication (HR 0.72, 95% CI 0.65-0.80, P<0.0001).

The main limitations of the studies were use of data from a single Boston medical center and a population restricted to only African American, Hispanic, and Caucasian patients. The findings may not be generalizable to the wider population.

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    Kristen Monaco is a senior staff writer, focusing on endocrinology, psychiatry, and nephrology news. Based out of the New York City office, she’s worked at the company since 2015.

Disclosures

The study was supported in part by the National Institutes of Health.

Apovian reported financial relationships with Nutrisystem, Zafgen, Sanofi‐Aventis, Orexigen, EnteroMedics, GI Dynamics, Scientific Intake, Gelesis, Novo Nordisk, SetPoint Health, Xeno Biosciences, Rhythm Pharmaceuticals, Eisai, Takeda, Aspire Bariatrics, the Vela Foundation, Energesis, Coherence Lab, and Science‐Smart. None of the other authors reported disclosures.

Primary Source

Obesity

Thomas D, et al “Weight recidivism after Roux?en?Y gastric bypass surgery: An 11?year experience in a multiethnic medical center” Obesity 2018; DOI: 10.1002/oby.22360.

Secondary Source

ObesityWeek

Anderson W, et al “The mitigating effect of weight loss medications on weight regain after gastric bypass surgery” ObesityWeek 2018; Abstract T-OR-2016.