Obesity imposes a hefty toll on both the nation and individuals. The CDC estimates that the condition cost the US a staggering $173 billion in 2019. Obese individuals pay the toll with an average of $1,861 higher medical costs annually. Yet, there's a less well-known cost to obesity.
A new study by researchers at the University of Michigan sheds light on a fascinating intersection between physical weight and mental abilities. Published in the Journal of Nutrition, Health & Aging, the study by Reynolds et al. explores the potential cognitive benefits of bariatric surgery, a popular weight loss intervention.
The Weighty Cost of Obesity:
"Individuals with obesity experience more rapid cognitive decline versus individuals without obesity," explains Evan Reynolds, Ph.D., a lead statistician at the NeuroNetwork for Emerging Therapies at Michigan Medicine (via EurekAlert!). This terrifying reality underscores the urgency of exploring interventions that could alter this trajectory.
The new study by Reynolds et al. aimed to discover if bariatric surgery could be a game-changer in obesity-related cognitive decline. It stands out compared to previous research for its scale and duration, with 87 participants, longer-term follow-up, and a more comprehensive battery of tests to determine the cognitive outcomes of bariatric surgery.
The new research uses the maligned yet standard measure for body composition: Body Mass Index (BMI). Participants in the study were classified as Class II or Class III according to CDC categories. The classes describe the extent of obesity, with a six-foot-tall man qualifying as obese at 225 lbs. Class II at 275 lbs. and Class III at 300 lbs.
A Surgical Solution To Obesity-Related Cognitive Decline:
As others before, the study suggests that the positive physical outcomes of bariatric surgery extend beyond the visible.
Assessing memory, cognition, emotion, motor, and sensory health, the researchers found "stable cognition two years after bariatric surgery," says Reynolds. Specifically, measures of executive function—the ability to plan, organize, and monitor one's attention—improved at the two-year assessment. However, one measure of verbal learning indicated a decline in delayed recall, hinting at a potential trade-off.
Reynolds et al. adopt a cautious stance, emphasizing the need for confirmatory randomized controlled trials. Despite the promising findings, they stress the importance of validating these results to ensure the credibility of the study's conclusions.
Landscape Of Future Research:
The study offers a more detailed perspective than other research demonstrating cognitive or memory improvement with various bariatric surgeries. Senior author Brian Callaghan, MD, emphasizes, "Metabolic factors, including diabetes and obesity, are associated with cognitive decline, but we still need to better understand how best to treat these factors to improve patients' cognitive outcomes."
In a landscape where the obesity epidemic exacts a substantial toll, this study not only uncovers the potential cognitive benefits of bariatric surgery but also injects a note of caution, underscoring the need for further exploration.
Sources: The Journal of Nutrition, Health & Aging, EurekAlert!, CDC (1)(2), Rehabilitation Psychology
