Adolescent weight history and adult cognition: before and after bariatric surgery

Abstract

Background: Cognitive deficits occur in a subset of individuals with obesity. Deficits can be reversed with bariatric surgery, though cognitive recovery is not equally exhibited across patients. Recent work has found that obesity during adolescence portends medical complications in adulthood; it is unknown if obesity in adolescence predicts adult cognition or cognitive recovery after weight loss surgery.

Objectives: The present study examines the relationship between weight history and cognitive function in obese adults undergoing bariatric surgery.

Setting: Academic medical centers with bariatric care services.

Methods: Seventy-eight bariatric surgery patients (mean age = 43.2 years) enrolled in an ancillary study to the Longitudinal Assessment of Bariatric Surgery (LABS) project completed a questionnaire recalling weight history at age 18. Cognitive testing was completed preoperatively and at 12-month follow-up.

Results: Weight status at age 18 was linked to performance in several aspects of cognition. Higher body mass index at age 18 predicted poorer preoperative verbal fluency (B = -.26, P = .045) as well as postoperative cognitive recovery in attention (B = -.30, P = .01) at 12-month follow-up.

Conclusion: Higher body mass index at age 18 predicts verbal fluency performance in adults with obesity, as well as postoperative recovery of attention after bariatric surgery. The mechanisms underlying this connection are not fully clear, though findings may reflect effects of obesity on the brain during a crucial period of neural maturation or duration of obesity and cumulative impact of co-morbidities on cognition. Future work examining possible causal factors involved in these relationships is needed.

Keywords: Bariatric; Cognition; Obesity; Weight history.

Figure 1

Y-axis represents T-score values. Bars plot the mean composite T-score for each cognitive domain; error bars represent standard deviations. There was a significant difference for all composites, except verbal fluency.

Figure 2

Y-axis represents T-score values. Bars plot the mean composite T-score for each cognitive domain 12 months after surgery; error bars represent standard deviations. There was a significant between BMI group difference for 12-month attention after adjustment for baseline hypertension, type 2 diabetes mellitus, sleep apnea, and baseline attention as well as duration of time since age 18; as shown, participants who were obese at the age of 18 exhibited lower attention performance post-surgery relative to their non-obese counterparts. No significant differences emerged for the other cognitive domains. BMI = body mass index.