There is a global increase in the prevalence of severe obesity in females during adolescence, which is a critical period for neurocognitive development. An increasing number of adolescents and young adults are now undergoing weight loss surgery as a treatment strategy for obesity. In addition to metabolic complications, obesity has been linked to neurocognitive comorbidity, and studies exploring cognitive performance in adolescents with severe obesity and the impact of bariatric surgery on cognitive abilities are limited. Verbal memory and executive function were assessed cross-sectionally in 69 females with moderate to severe obesity and 24 females without obesity, 13-24 years old. In an exploratory analysis, cognitive changes were also assessed longitudinally over 12 months in a subset of 35 females with moderate to severe obesity following weight loss surgery (n = 21) or following usual care without surgery (n = 14). In cross-sectional analysis, females with moderate to severe obesity showed lower scores for short-term and long-term recall (verbal memory) and response inhibition and cognitive flexibility (executive function) than the comparison group, when adjusted for age and baseline intelligence. Females with moderate to severe obesity who underwent surgery showed significant weight loss but no improvement in verbal memory and executive function scores over 12 months compared with those who did not have surgery. Females with moderate to severe obesity demonstrate worse performance in tests of verbal memory and executive function than the comparison group without obesity. In addition, exploratory analyses provide no indication that weight loss surgery improves these observed cognitive decrements over a period of 12 months. Further studies are necessary to comprehensively evaluate changes in cognitive function following bariatric surgery.
Keywords: Adolescents; Bariatric surgery; Executive function; Memory; Moderate to severe obesity; Young adults.