BACKGROUND AND STUDY AIMS: Lactase non-persistence (LNP), or primary hypolactasia, is a genetic condition that mediates lactose malabsorption and can cause lactose intolerance. Here we report the prevalence of lactose intolerance in a double-blind placebo study. METHODS: The LCT C>T-13910 variant was genotyped by RT-PCR in 121 volunteers and lactose malabsorption was assessed using the hydrogen breath test (HBT) after consuming 25 g of lactose. Lactose intolerance was assessed by scoring symptoms (SS) using a standardized questionnaire following challenge with a lactose solution or saccharose placebo. RESULTS: The LNP genotype was observed in 57% of the volunteers, among whom 87% were HBT⁺. In the HBT⁺ group the median SS was 9 and in the HBT⁻ group the median SS was 3 (p < 0.001). No difference was observed in the SS when both groups were challenged with the placebo. The most common symptoms included audible bowel sounds, abdominal pain and meteorism. In the ROC curve analysis, an SS ≥ 6 demonstrated 72% sensitivity and 81% specificity for predicting a positive HBT. To estimate prevalence, lactose intolerance was defined as the presence of an SS ≥ 6 points after subtracting the placebo effect and 34% of the study population met this definition. CONCLUSIONS: The LNP genotype was present in more than half of subjects evaluated and the observed prevalence of lactose intolerance was 34%.
RCT Entities:
BACKGROUND AND STUDY AIMS: Lactase non-persistence (LNP), or primary hypolactasia, is a genetic condition that mediates lactose malabsorption and can cause lactose intolerance. Here we report the prevalence of lactose intolerance in a double-blind placebo study. METHODS: The LCT C>T-13910 variant was genotyped by RT-PCR in 121 volunteers and lactose malabsorption was assessed using the hydrogen breath test (HBT) after consuming 25 g of lactose. Lactose intolerance was assessed by scoring symptoms (SS) using a standardized questionnaire following challenge with a lactose solution or saccharose placebo. RESULTS: The LNP genotype was observed in 57% of the volunteers, among whom 87% were HBT⁺. In the HBT⁺ group the median SS was 9 and in the HBT⁻ group the median SS was 3 (p < 0.001). No difference was observed in the SS when both groups were challenged with the placebo. The most common symptoms included audible bowel sounds, abdominal pain and meteorism. In the ROC curve analysis, an SS ≥ 6 demonstrated 72% sensitivity and 81% specificity for predicting a positive HBT. To estimate prevalence, lactose intolerance was defined as the presence of an SS ≥ 6 points after subtracting the placebo effect and 34% of the study population met this definition. CONCLUSIONS: The LNP genotype was present in more than half of subjects evaluated and the observed prevalence of lactose intolerance was 34%.
Authors: Jian-Feng Yang; Mark Fox; Hua Chu; Xia Zheng; Yan-Qin Long; Daniel Pohl; Michael Fried; Ning Dai Journal: World J Gastroenterol Date: 2015-06-28 Impact factor: 5.742
Authors: Ana Cecília Guimarães Alves; Natalie Mary Sukow; Gabriel Adelman Cipolla; Marla Mendes; Thiago P Leal; Maria Luiza Petzl-Erler; Ricardo Lehtonen Rodrigues Souza; Ilíada Rainha de Souza; Cesar Sanchez; Meddly Santolalla; Douglas Loesch; Michael Dean; Moara Machado; Jee-Young Moon; Robert Kaplan; Kari E North; Scott Weiss; Mauricio L Barreto; M Fernanda Lima-Costa; Heinner Guio; Omar Cáceres; Carlos Padilla; Eduardo Tarazona-Santos; Ignacio F Mata; Elena Dieguez; Víctor Raggio; Andres Lescano; Vitor Tumas; Vanderci Borges; Henrique B Ferraz; Carlos R Rieder; Artur Schumacher-Schuh; Bruno L Santos-Lobato; Pedro Chana-Cuevas; William Fernandez; Gonzalo Arboleda; Humberto Arboleda; Carlos E Arboleda-Bustos; Timothy D O'Connor; Marcia Holsbach Beltrame; Victor Borda Journal: Front Genet Date: 2021-09-22 Impact factor: 4.599
Authors: Alba Rocco; Debora Compare; Costantino Sgamato; Alberto Martino; Luca De Simone; Pietro Coccoli; Maria Laura Melone; Gerardo Nardone Journal: Nutrients Date: 2021-05-13 Impact factor: 5.717