Healthy Eating Index-2020 and post-stroke depression (PSD): cross-sectional analysis of NHANES data

Area of Science:

• Nutritional Psychiatry
• Neurology
• Public Health

Background:

• Post-stroke depression (PSD) significantly impairs functional recovery and quality of life after stroke.
• Dietary quality is linked to depression in the general population, but its role in PSD is under-researched.

Purpose of the Study:

• To investigate the cross-sectional association between dietary quality, assessed by the Healthy Eating Index-2020 (HEI-2020), and probable post-stroke depression (PSD).
• To explore potential mediating roles of gut microbiota-related dietary patterns in the association between HEI-2020 and PSD.

Main Methods:

• Analysis of 962 adults with a history of stroke from the National Health and Nutrition Examination Survey (2005-2018).
• Assessment of depressive symptoms using the Patient Health Questionnaire-9 (PHQ-9; score ≥ 10 indicating probable depression).
• Evaluation of dietary quality using HEI-2020 scores, with tertile categorization and multivariate logistic regression, spline analysis, and mediation analysis.

Main Results:

• Each one-point increase in HEI-2020 score was associated with a 2% reduction in the odds of probable depression.
• Individuals in the highest tertile of dietary quality had 59% lower odds of probable depression compared to the lowest tertile.
• A nonlinear, inverse association was observed when HEI-2020 scores exceeded 57, with significant race/ethnicity interaction.

Conclusions:

• Higher adherence to the HEI-2020 dietary pattern is inversely associated with probable post-stroke depression (PSD) in a nonlinear and race-specific manner.
• The Dietary Index for Gut Microbiota (DI-GM) demonstrated an inconsistent indirect association, suggesting a suppressive rather than mediating role.
• Findings are observational, highlighting the need for prospective studies to establish causality and explore gut-brain axis mechanisms in PSD.