Symptoms of lactose intolerance are often attributed to lactose malabsorption but, as this relationship has not been demonstrated when a small dose of lactose similar to that contained in one cup of milk is ingested by intolerant patients, psychological factors may play a role in altered symptom perception.
Dr Basilisco and colleagues from Italy assessed the hypothesis that the psychological profile influences the symptoms of lactose intolerance.
The team reported that 102 consecutive patients underwent a 15 g lactose hydrogen breath test to assess lactose malabsorption.
The patients recorded the presence and severity of symptoms of lactose intolerance during the breath test using visual analogue scales.
|Health-related quality of life was reduced in patients with somatization|
|Alimentary Pharmacology & Therapeutics|
The psychological profile was assessed using a psychological symptom checklist, and health-related quality of life by means of the short-form health survey.
Lactose malabsorption and intolerance were diagnosed in, respectively, 18% and 29% of the patients.
The team found that the 2 conditions were not associated, and the severity of intolerance was even less in the patients with malabsorption.
The researchers showed that a high somatization t-score was significantly associated with lactose intolerance.
The effects of the other psychological variables and of lactose malabsorption were not statistically significant.
The team found that health-related quality of life was significantly reduced in the patients with somatization, but not in those with lactose malabsorption.
Dr Basilisco's team concludes, "The symptoms of lactose intolerance during hydrogen breath testing at a low physiological lactose load, are unrelated to lactose malabsorption, but may reveal a tendency towards somatization that could impair the quality of life."