Obesity Linked to Decreased Hippocampal Volume

the Neurology Advisor take:

Study results presented at the Society for Neuroscience 2014 Annual Meeting in Washington, D.C. showed a correlation between poor brain health and obesity in cognitively healthy adults.

The data, which was sourced from the Australian PATH Through Life study, showed that adult participants in their 60s who were overweight or obese had smaller hippocampal volume and saw greater hippocampal atrophy over eight years compared to normal-weight participants.

The study collected data on 420 cognitively healthy adults aged 60 to 64 years. Both body mass index (BMI) and high-resolution T1-weighted MRI were recorded. At baseline, BMI was negatively correlated with left hippocampal volume (estimate per unit BMI above 25: –10.65 mm³; P = .027) and right hippocampal volume. (estimate: –8.18 mm³; P = .097).

Upon follow-up four and eight years later, participants with a higher BMI showed greater left hippocampal atrophy than right hippocampal atrophy after adjustment for various factors. Every two-point increase in BMI was associated with a 7.2% decrease in left hippocampal volume.

While the researchers did not investigate how the hippocampus shrinkage affects function, the outcome is of great interest since other studies have shown a relationship between hippocampal shrinkage, cognitive decline, and an increased risk of dementia.