Diet Quality Could Be a Key Treatment Target for Patients With Depression

Depression severity was correlated with dietary quality in patients who reported appetite loss, according to study data published in the Journal of Affective Disorders. The same trend was not observed in patients with depression who reported increased appetite.

Kaiping Burrows, PhD, of the Laureate Institute for Brain Research in Tulsa, Oklahoma, and collaborators recruited patients with current major depressive disorder (MDD) between August 2012 and May 2017. Eligible patients were unmedicated for depression and had no significant medical comorbidities, including suicidal ideation, eating disorders, and recent substance use disorders.

The study divided the sample into 3 distinct groups: patients with MDD with increased appetite (MDD-IN; n=22; mean age, 31.41±8.53 years; 22.7% men), patients with MDD with decreased appetite (MDD-DE; n=39; mean age, 30.13±9.49 years; 35.9% men), and healthy controls without depression (HC; n=42; mean age, 31.33±8.56 years; 35.7% men). All participants completed a 24-hour dietary recall survey and were evaluated for depression and anxiety symptoms using the Hamilton Anxiety and Depression Rating Scales.

Subjects were provided breakfast at their study visit and blood plasma samples were collected 3.5 hours after breakfast completion for the analysis of inflammation-related biomarkers. Healthy Eating Index (HEI) and Dietary Inflammation Index (DII) scores were calculated from dietary recall responses, taking into account 38 food parameters. Depression symptom severity, inflammatory biomarker levels, socioeconomic status, and HEI and DII scores were compared between groups.  

Compared with healthy controls, the MDD-DE group had lower scores on HEI total fruit (P =.031), total vegetables (P =.007), whole grains (P =.013), seafood and plant protein (P <.001), and empty calories (P <.001) subscale scores, as well as lower HEI total score (P <.001). The MDD-IN group had lower total fruit (P =.037), empty calories (P =.002), and HEI total (P =.009) scores than controls. Compared with the MDD-IN group, the MDD-DE showed lower protein (P =.012) and total fat intake (P =.016). Lower HEI scores were associated with higher depression (P =.026) and anxiety (P =.024) scores in the MDD-DE group, but not in the MDD-IN group.

Regarding dietary inflammation, both MDD groups had significantly increased DII scores compared with controls. The patient groups also had elevated levels of interleukin-1 receptor antagonist (P =.048) and interleukin-6 (P =.004). In the MDD-DE group, higher DII scores were associated with more severe anxiety symptoms (P =.016). The same trend was not apparent for the MDD-IN group; in fact, higher DII correlated with decreased anxiety rating scale scores (P =.023). No significant relationship between depression symptoms and DII scores were observed in any patient group.

These data suggest that dietary quality may play an important role in mediating symptom severity in patients with MDD-DE. As a cross-sectional study with limited cohort size, however, results must be extrapolated with care. The investigators wrote, “Taken together, these results support the idea that dietary quality may be a modifiable treatment target for individuals who report a decrease in appetite during their major depressive episode.”

Reference

Burrows K, Stewart JL, Antonacci C, et al. Association of poorer dietary quality and higher dietary inflammation with greater symptom severity in depressed individuals with appetite loss [published online December 2, 2019]. J Affect Disord. doi:10.1016/j.jad.2019.11.160