Do psychological factors predict symptom severity in patients with subjective food hypersensitivity?

We examined whether psychological factors such as general and gastrointestinal symptom-specific anxiety and depression could predict symptom severity in patients with unexplained, self-reported (subjective) food hypersensitivity. For the purpose, we translated and validated the Visceral Sensitivity Index (VSI).

Seventy consecutive patients completed questionnaires for Hospital Anxiety and Depression Scale, VSI, Irritable Bowel Syndrome Symptom Questionnaire, and Subjective Health Complaints Inventory. Relationship between scores on psychological factors and scores on somatic symptoms were studied by multiple regression analyses.

Most patients reported non-gastrointestinal symptoms in addition to their irritable bowel syndrome complaints, but general and symptom-specific anxiety, and depression could not explain a significant amount of the variance in somatic complaints. Gastrointestinal symptom-specific anxiety was a significant predictor of gastrointestinal complaints (p = 0.02), and age was the sole significant predictor of non-gastrointestinal complaints (p = 0.01). Approximately 90% of the total variance in symptom severity remained unexplained by the psychological factors. The Norwegian version of the VSI had satisfactory validity (Cronbach alfa = 0.93). Symptom-specific and general anxiety were significantly correlated (r = 0.48, p < or = 0.0001).

Psychological factors were not major predictors of symptom severity in patients with subjective food hypersensitivity. The Norwegian version of VSI had satisfactory validity.