Pancreatic Polypeptide Linked to Anxiety in Obese Men But Not Women | Research

The takeaway

Among NPY-family peptides, only pancreatic polypeptide (PP) showed a moderate association with perceived anxiety in obese men, suggesting sex-specific gut-brain-axis effects on mood.

PP-anxiety link in men only
Among three NPY-family peptides, only pancreatic polypeptide showed mood associations, and only in obese men

What the researchers found

Pancreatic polypeptide (PP) plasma levels showed a moderate association with perceived anxiety specifically in obese men. NPY and PYY were not associated with anxiety, depressiveness, or perceived stress.

Why it matters

Obesity and anxiety commonly co-occur, but the biological link is poorly understood. PP's sex-specific association with anxiety suggests the gut-brain axis may contribute differently to mental health in obese men versus women.

The numbers in context

144 patients; PP-anxiety r=0.41 p=0.007 in men; women had higher anxiety (8.13 vs 5.93) and stress (52.62 vs 41.23); no NPY/PYY mood associations

How the study worked

Cross-sectional observational study in 144 obese patients. Measured plasma NPY, PYY, and PP levels. Assessed anxiety, depressiveness, and perceived stress using validated questionnaires. Analyzed associations with sex-stratified statistical models.

Who was studied

Severely obese inpatients (90F, 54M, mean BMI 49.4 kg/m²)

What this study cannot tell us

Cross-sectional — cannot determine causation. Moderate sample size. Only obese participants — may not apply to normal weight. PP-anxiety association was moderate, not strong. Self-reported psychological measures.

How to read the evidence

Moderate — adequately powered observational study (n=144) with validated measures, but cross-sectional design limits causal inference.

When this study was published

Published in 2020; gut peptide-mood interactions in obesity remain an active research area.

The bigger picture

This adds to growing evidence that gut-derived peptides influence brain function and mood, not just appetite. The sex-specific finding aligns with known gender differences in both anxiety disorders and gut hormone regulation.

Questions still open

Does PP directly influence brain anxiety circuits or is it a marker of another process?
Why is the PP-anxiety association sex-specific?
Would PP receptor modulation affect anxiety in obese individuals?

Common questions

What is pancreatic polypeptide and how does it relate to anxiety?

PP is a hormone released by the pancreas after eating that helps regulate appetite. This study suggests it may also communicate with brain areas involved in anxiety, particularly in obese men, though the mechanism is not yet clear.

Why would gut hormones affect mood differently in men and women?

Men and women differ in gut hormone levels, brain receptor distributions, and stress response systems. These biological differences may cause the same gut signals to produce different psychological effects.

Read the original research

Pancreatic Polypeptide but Not Other Members of the Neuropeptide Y Family Shows a Moderate Association With Perceived Anxiety in Obese Men.

Frontiers in human neuroscience, 14, 578578

View on PubMed ↗Publisher’s paper ↗

Citation

Schaper, Selina Johanna; Hofmann, Tobias; Wölk, Ellen; Weibert, Elena; Rose, Matthias; Stengel, Andreas. (2020). Pancreatic Polypeptide but Not Other Members of the Neuropeptide Y Family Shows a Moderate Association With Perceived Anxiety in Obese Men.. Frontiers in human neuroscience, 14, 578578. https://doi.org/10.3389/fnhum.2020.578578