Objective: Results from general population studies suggest a relationship between gastrointestinal (GI) symptoms, depression, and anxiety. However, no primary care study has investigated this issue. This study investigates the prevalence of GI symptoms in primary care and their association with depression and anxiety.
Method: Within a cross-sectional survey, 2091 consecutive patients from 15 primary care clinics in the United States completed self-report questionnaires regarding GI symptoms [15-item Patient Health Questionnaire (PHQ-15)], anxiety [seven-item Generalized Anxiety Disorder Scale (GAD-7)], and depression (PHQ-8). Of those, 965 randomly selected patients additionally underwent a criterion standard diagnostic telephone interview (Structured Clinical Interview for DSM-IV) for the most common anxiety disorders.
Results: A total of 380 [18% (95% CI, 16.3% to 19.3%)] patients reported to be substantially bothered by at least one GI symptom in the previous 4 weeks. The prevalence of severe levels of depression (PHQ-8 score > or =15) was nearly fivefold in patients with GI symptoms compared to patients without GI symptoms (19.1% vs. 3.9%; P<.001), and the prevalence of severe levels of anxiety (GAD-7 score > or =15) was nearly fourfold in patients with GI symptoms compared to patients without GI symptoms (19.4% vs. 5.6%; P<.001). Similarly, with each additional GI symptom, the odds for an interview-based diagnosis of specific anxiety disorders increased significantly: For example, compared to patients with no GI symptom, the odds ratio (OR) (95% CI) for generalized anxiety disorder in patients with one GI symptom was 3.7 (2.0 to 6.9); in patients with two GI symptoms, OR=6.5 (3.1 to 13.6); and in patients with three GI symptoms, OR=7.2 (2.7 to 18.8).
Conclusion: GI symptoms are associated significantly with depression and anxiety in primary care. It is suggested to screen as a routine for anxiety and depression in patients with GI symptoms and, if indicated, to initiate specific treatment.