Impact of orocecal transit time on patient's perception of lactose intolerance Influencia del tiempo de tránsito orocecal en la percepción de los síntomas de intolerancia a la lactosa

Background: symptoms attributed to the lactose intolerance are an important public health issue because of their prevalence and social relevance. Also because they may cause undue rejection of dairy products consume with potential health consequences. Transit time is a putative factor implied in the severity of symptoms associated with lactose. Objectives: to elucidate the relation between orocecal transit time (OCTT) and lactose intolerance symptoms. Methods: observational study in patients referred to a lactose hydrogen breath test who showed an increase in breath H2 excretion higher than 25 ppm. OCTT was measured with the breath test and symptoms of lactose tolerance with a validated scale. Symptoms were measured twice: before receiving the lactose, inquiring about self perceived symptoms when patients consumed dairy products at home ("home symptoms"), and again after completing the lactose breath test ("test symptoms"). Results: 161 patients were included. There was no correlation between OCTT and home symptoms (r = -0.1). When OCTT was faster than 60 minutes, intensity of "test symptoms" was similar to "home symptoms". However, in patients with normal or slow OCTT, the "home symptoms" were more intense than the "test symptoms" (p < 0.05). At home, symptoms were independent of OCTT but with the lactose test load the symptoms were proportionately more intense with faster OCTT. Conclusions: in lactose maldigesters, selfreported symptoms of lactose intolerance are more pronounced at home than after a high lactose challenge. Intolerance symptoms that patients attributed to lactose consume at home are due to factors other than fast OCTT. Antecedentes: los síntomas atribuidos a la intolerancia a la lactosa son un importante problema de salud pública. El tiempo de tránsito es un factor implicado en la severidad de los síntomas asociados al consumo de lactosa. Objetivos: elucidar la relación entre el tiempo de tránsito orocecal (TTOC) y los síntomas de intolerancia a la lactosa. Métodos: estudio observacional en pacientes con un test del aliento de hidrógeno con lactosa patológico (excreción de hidrógeno superior a 25 ppm). El TTOC se midió mediante el test del aliento y los síntomas mediante una escala previamente validada. Los síntomas se determinaron dos veces: antes de recibir la lactosa, preguntando acerca de los síntomas en casa cuando se consumen lácteos ("síntomas en casa"), y de nuevo después de completar el test del aliento con lactosa ("síntomas test"). Resultados: se han incluido 161 pacientes. No se observa correlación entre el TTOC y los sínto