Energy intake reductions predict greater weight loss after bariatric surgery
A predictor of long-term weight loss is the level of energy restriction achieved at 0.5 years after bariatric surgery, according to a study, adding that weight loss correlates with a changing dietary macronutrient composition.
Short-term changes in energy intake (p<0.001) and in relative proportions of energy from carbohydrates (p<0.001), fat (p<0.001) and protein (p<0.05) correlated with 10-year weight change after bariatric surgery.
During the 10-year follow-up, men and women with the largest reductions in energy intake had greater weight loss (7.3 and 3.9 percent, respectively) than those with the smallest intake reductions (p<0.001).
Furthermore, men and women who favoured protein and carbohydrates over fat and those who favoured protein over carbohydrates had lost more weight than individuals who favoured the opposite changes in macronutrient composition (p<0.05).
To determine whether short-term changes (≤0.5 year postsurgery) in energy intake and macronutrient composition after bariatric surgery could predict 10-year weight change, researchers recruited participants from the Swedish Obese Subjects study, a matched, nonrandomized, prospective trial comparing bariatric surgery with usual care for obese patients.
Included in the study were 2,010 patients who underwent bariatric surgery. They completed physical examinations and questionnaires before and 0.5, 1, 2, 3, 4, 6, 8 and 10 years after surgery. A linear mixed model was used for analysis, including repeated measures with a random intercept and an unstructured covariance matrix.
“Approximately 20 to 30 percent of obese patients do not achieve successful weight outcomes after bariatric surgery,” according to researchers.