NASHVILLE -- Understanding variations among obesity subtypes may help physicians do a better job of predicting bariatric surgery outcomes, researchers reported here.
In a large analysis of nearly 2,500 individuals with obesity from the , four specific subtypes of obesity were identified -- comorbid diabetes with low rates of high-density lipoprotein, disordered eating, mixed, and early onset -- all with very distinct clinical characteristics and responses to certain therapies, according to Alison Field, ScD, of Brown University in Providence, and colleagues.
The findings were presented at the Obesity Week, a joint meeting of The Obesity Society and the American Society for Metabolic & Bariatric Surgery. The results were also simultaneously published in the journal, .
"I published a suggesting that the heterogeneity in obesity may be hindering the field from finding effective treatments and risk factors," Field told Ƶ. "I had used latent class analysis to identify subtypes of eating disorders. I found that there were differences between the subtypes in terms of the development of adverse outcomes. The LABS study team was open to using the same approach to identify subtypes of obesity."
The analysis followed the individuals for 7 years following bariatric surgery, with weight measured annually. Participants completed questionnaires regarding satisfaction with their weight loss after surgery, reasons for eating that excluded hunger, binge eating behaviors and feelings of loss of control, as well as other clinical markers.
Among the four subtypes of obesity, the "mixed" type of obesity was the most common form, seen in more than 45% of the cohort. The second most common was disordered eating (36%), followed by extreme obesity with early onset (15%). Obesity with diabetes and low HDL cholesterol was the least common form (4%).
Those with early onset obesity tended to have the highest BMI, with higher BMI levels at the age of 18, too. This group also was more likely to report a "dream BMI" that fell into the overweight range (around 26.5).
"I was surprised by how distinct some of the subtypes were," Field noted. "For example, in one group almost everyone engaged in eating when not hungry and being very responsive to food cues [the disordered eating category]. In another group those behaviors were extremely rare."
As for weight loss outcomes 3 years after bariatric surgery, those who fell into the disordered eating subtype of obesity reported the largest postoperative weight change. Men and women with early onset obesity lost an average of 25% and 30% less, respectively. Similar weight loss was also seen among those with the diabetes subtype of obesity.
These patterns of weight loss according to obesity subtype held consistent for those who underwent Roux-en-Y or gastric banding.
Field suggested "it would be prudent to consider additional treatment modalities for patients with childhood onset obesity and to monitor changes in appetite behaviors after surgery."
In an , Penny Gordon-Larsen, PhD, of the University of North Carolina in Chapel Hill, praised Field and co-authors for their wide inclusion of psychological, behavioral, and biological factors that "moved beyond the status quo literature." She was also pleased that the researchers offered a move away from the "one-size-fits-all approach."
But Gordon-Larsen also noted some limitations of this study stemming from use of the LABS cohort, which included mainly non-Hispanic white females. "In addition, Field et al. did not address genetic susceptibility to postsurgical weight loss, and there may be additional metabolic and physiological factors that are predictive of treatment response, which should be addressed in future studies," she wrote.
Disclosures
LABS-2 was funded by the National Institute of Diabetes and Digestive and Kidney Diseases.
Co-authors on the study reported relationships with Covidien, Ethicon J&J Healthcare, Ethicon Endosurgery, Sanofi, Nestlé, and W.L. Gore & Associates.
Primary Source
Obesity
Field A, et al “Association of obesity subtypes in the Longitudinal Assessment of Bariatric Surgery Study and 3-year postoperative weight change” Obesity 2018; DOI: 10.1002/oby.22287.
Secondary Source
Obesity
Gordon-Larsen, P “Heterogeneity in obesity: More research needed to improve precision weight loss treatment” Obesity 2018; DOI: 10.1002/oby.22333.