The relationship between gluten free diet adherence and depressive symptoms in adults with coeliac disease: A systematic review with meta-analysis

Abstract

Purpose: Depressive symptoms are common in patients with coeliac disease (CD) and may represent a barrier to gluten free diet (GFD) adherence. The aims of this meta-analysis were: (1) to synthesise the evidence on the relationship between depression or depressive symptoms and degree of adherence to a GFD in patients with CD who are already attempting a GFD (i.e., post-diagnosis and onset of GFD), and (2) to summarise the direction of causation of any observed relationship.

Methods: A random effects meta-analysis of 8 cross-sectional studies (N = 1644) was conducted. Included studies measured self-reported depressive symptoms and GFD adherence using either a dietitian interview or validated self-report questionnaire that considered unintentional gluten consumption.

Results: There was a moderate association between poorer GFD adherence and greater depressive symptoms (r = 0.398, 95% CI = 0.321-0.469), with marked heterogeneity in the effects (I² = 66.8%). A sensitivity analysis excluding studies with a moderate/high (k = 1) or unclear risk of bias (k = 1) did not change the results.

Conclusion: The low number of studies meeting inclusion criteria limits the strength of the conclusions. Available evidence suggests there is an association between poorer GFD adherence and self-reported depressive symptoms; however, studies using longitudinal and prospective designs, and reliable measures, particularly for adherence, are needed to confirm this association. The direction of causation between depression and adherence remains unclear.

Keywords: Coeliac disease; Depression; Depressive symptoms; Gluten free diet adherence; Meta-analysis.