The association of Dietary Quality Index-International (DQII) score with anxiety and depression: Results of a population-based study

Abstract

Background

Recent evidence indicates a relationship between diet quality and prevalent psychiatric disorders, though, the nature of this association remains unclear. This study aimed to investigate the association between the Dietary Quality Index-International (DQII) score and the severity of depression and anxiety.

Methods

This cross-sectional research involved 6472 individuals aged 35–65 from the Mashhad stroke and heart atherosclerotic disorder (MASHAD) study. Dietary intake was assessed using a validated food frequency questionnaire (FFQ), and dietary quality was evaluated using the DQI-I score. The severity scores of depression and anxiety were measured through the Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI).

Results

Participants in the highest tertile of DQI-I had lower anxiety and depression severity scores than those in lower tertiles (P < 0.001). After adjusting for confounders, the association remained significant only for depression score (OR = 0.85; 95 % CI: 0.73–0.98; p = 0.02). Among DQI-I components, only overall balance was significantly associated with depression score (OR = 0.86; 95 % CI: 0.75–1.00; p = 0.04). Higher variety and adequacy scores were linked to lower odds of anxiety score (OR = 0.75; 95 % CI: 0.61–0.93; p < 0.01 and OR = 0.79; 95 % CI: 0.66–0.96; p = 0.02).

Limitations

The cross-sectional design restricts causal inference, FFQs introduce recall bias, and unmeasured confounding remains a possibility.

Conclusion

Individuals in the highest DQI-I tertile had lower odds of severe depression score. Overall balance correlated significantly with depression severity score, while higher variety and adequacy scores were linked to reduced severe anxiety score.