Perceived food intolerance in subjects with irritable bowel syndrome-- etiology, prevalence and consequences.

OBJECTIVES: This study estimates the prevalence of perceived food intolerance and its consequences in subjects with irritable bowel syndrome (IBS), evaluates the utility of common tests for food intolerance, studies the relation between perceived food intolerance and other disorders, and discusses the etiology. DESIGN: Cross-sectional study. SETTING: National health survey. SUBJECTS: A selection of the population (n=11,078) in Oppland county, Norway, was invited to a health screening, and a sample of subjects with IBS were included in the study. INTERVENTIONS: A medical history of food intolerance, musculoskeletal pain, mood disorders and abdominal complaints was taken, and tests were performed for food allergy and malabsorption. A dietician evaluated the dietary habits of the subjects. RESULTS: Out of 4,622 subjects with adequately filled-in questionnaires, 84 were included in the study, 59 (70%) had symptoms related to intake of food, 62% limited or excluded food items from the diet and 12% had an inadequate diet. The mean numbers of food items related to symptoms and the number of foods limited or excluded from the diet were 4.8 and 2.5, respectively. There were no associations between the tests for food allergy and malabsorption and perceived food intolerance. Perceived food intolerance was unrelated to musculoskeletal pain and mood disorders. CONCLUSIONS: Perceived food intolerance is a common problem with significant nutritional consequences in a population with IBS. The uselessness of current antibody tests and tests for malabsorption and the lack of correlation to psychiatric co-morbidity make the etiology obscure.

The value of a general therapeutic approach in subjects with irritable bowel syndrome.

BACKGROUND: The general therapeutic approach is the cornerstone in the management of irritable bowel syndrome, but the effect is poorly documented. AIM: To evaluate the effect of the general therapeutic approach for irritable bowel syndrome. METHODS: Subjects with irritable bowel syndrome identified in a public screening were included. Scores for abdominal symptom (range 0-12), musculoskeletal pain and mood disorders were calculated. After exclusion of other disorders, a doctor presented irritable bowel syndrome as a positive diagnosis, gave information, reassurance and lifestyle advice, but no pharmacotherapy. A dietician gave dietary advice. There was a follow-up after 6 months. RESULTS: Sixty-five persons (females/males: 44/21) with mean age 49 years (range 31-76) were included, 31 (48%) were recommended dietary changes. Twenty subjects (31%) had satisfactory relief of symptoms after 6 months. The scores for abdominal symptom was reduced from 3.1 to 2.2 (P = 0.007), the reduction was 2.2 in the diarrhoea-predominant group given advice compared with 0.4 in the other subjects (P = 0.035). Previous consultations for the complaints, visits for psychiatric disorders, and presence of mood disorders were predictors of persistent complaints. CONCLUSIONS: There was a significant relief of symptoms after 6 months, those with psychological co-morbidity responded less well. The effect of dietary advice was only seen in those with diarrhoea-predominant irritable bowel syndrome.

Lactose malabsorption in a population with irritable bowel syndrome: prevalence and symptoms. A case-control study.

BACKGROUND: Symptoms after intake of milk are common in persons with irritable bowel syndrome (IBS). The aims of this study were to compare the prevalence of lactose malabsorption (LM) and symptoms related to intake of milk and lactose in subjects with IBS with that of healthy volunteers, and to search for symptoms that are characteristic of LM. METHODS: A case-control study in a Norwegian population was initiated. Subjects with IBS were asked for symptoms related to intake of milk and lactose, tested for LM, and compared with a group of healthy volunteers. RESULTS: The study comprised a total of 187 persons (82 with IBS and 105 volunteers), females/males: 138/49, mean age 47 years. In subjects with IBS and in healthy volunteers, LM was present in 3/74 (4.1%) and 4/105 (3.8%), respectively (ns), milk-related symptoms in 32/79 (40%) and 13/105 (12%), respectively (P < 0.001) and symptoms after intake of lactose in 28/74 (38%) and 21/104 (20%), respectively (P=0.01). Borborygmi starting within 5 h after intake of lactose and lasting for more than 2 h indicated LM (OR 61 (95% CI: 8-475), P < 0.001). CONCLUSIONS: IBS and LM are unrelated disorders in a Norwegian population. Milk-related symptoms and symptoms after intake of lactose are unreliable predictors for LM. Precise symptom-based criteria might enhance the diagnostic accuracy for LM.