Anxiety but not depression decreases in coeliac patients after one-year gluten-free diet: A longitudinal study

Background: A high prevalence of anxiety and depression has been reported in untreated coeliac disease (CD) patients. At present, the role of a gluten-free diet (GFD) on psychological disorders is still poorly known. The aim of this study was to evaluate state and trait anxiety and depression in adult CD patients before and after 1 year of GFD. Methods: A total of 35 CD patients were studied before and after 1 year of GFD. A total of 59 healthy subjects matched for gender, age and socio-economic status were studied as a control group. State and trait anxiety were assessed with the STAI test; depression was assessed using the modified version of the SDS Zung self-rating depression scale (M-SDS). The tests were administered before (TO) and after 1 year of GFD (T1). Results: At T0, CD patients showed high levels of state anxiety in a significantly higher percentage compared to controls (71.4% versus 23.7%; P <0.0001), while there was no significant difference in trait anxiety between groups (25.7% versus 15.2%; P:ns); the percentage of subjects with depression was significantly higher in the CD group than in the control group (57.1% versus 9.6%; P <0.0001). At T1, a significant decrease in the percentage of state anxiety was found in CD patients (T0: 71.4% versus T1: 25.7%; P <0.001), while there were no significant changes in the percentage of trait anxiety (T0: 25.7% versus T1: 17.1%; P:ns) or depression (T0: 57.1.% versus T1: 45.7%; P:ns), which was still present in a significantly higher percentage in treated CD compared to controls (P <0.0001). Conclusion: In CD patients anxiety is present in a predominantly reactive form and it decreases after GFD. Depression is present in a higher percentage in CD patients and 1 year of GFD fails significantly to affect depressive symptoms. The presence of depression after GFD could be related to the reduction in quality of life in CD patients. The non-regression of depression after GFD could suggest that these patients need psychological support.