title: Perception of lactose intolerance impairs health-related quality of life.
abstract: Chronic conditions impair perception of well-being. Malabsorption of lactose is the most frequent form of malabsorption and manifests as lactose intolerance. There is a lack of information regarding their impact on self-perception of health. The objective of this study is to determine the subjective impact of self-reported lactose intolerance or objective lactose malabsorption on patient health by using a patient-reported outcome to measure health-related quality of life (HRQOL) and modification of lactose-containing food diet.
  
  
  
  A 3-year prospective, cross-sectional study was performed in patients referred for a lactose hydrogen breath test. Patients were asked about their subjective opinion relative to their lactose tolerance and completed a validated, specific questionnaire to determine symptoms of intolerance during habitual consumption of dairy. A 50-g lactose breath test was then performed. Patients were grouped as absorbers vs malabsorbers and tolerant vs intolerants.
  
  
  
  A total of 580 patients were included (median age 30 years, 419 female). Overall, 324 patients (56%) considered themselves lactose intolerant and that perception was associated with avoidance of dairy consumption (55% vs only 9% of self-defined tolerants). Self-perception of intolerance was associated with lower HRQOL scores (median, 60 vs 70, P<0.01). In contrast, lactose objective malabsorption was not clearly associated with dairy avoidance (41% of malabsorbers avoided dairy vs 31% of absorbers). However, HRQOL scores were also significantly lower in malabsorbers than in absorbers (60 vs 70 respectively, P<0.001).
  
  
  
  Subjective perception of lactose intolerance affects the decision to avoid dairy even more than objective malabsorption. However, both self-perception of lactose intolerance and objective lactose malabsorption are associated with poorer perceived quality of life.
authors.affiliation: Digestive System Research Unit, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Casellas
authors.affiliation: Digestive System Research Unit, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Aparici
authors.affiliation: Digestive System Research Unit, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
authors.forename: M J
authors.initials: MJ
authors.lastname: Pérez
authors.affiliation: Digestive System Research Unit, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Rodríguez
mesh_terms: D000328:Adult; D001944:Breath Tests; D003430:Cross-Sectional Studies; D003657:Decision Making; D059026:Diagnostic Self Evaluation; D004032:Diet; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D007408:Intestinal Absorption; D007785:Lactose / Q000378:metabolism*; D007787:Lactose Intolerance / Q000523:psychology; D008297:Male; D008875:Middle Aged; D010465:Perception; D011446:Prospective Studies; D011788:Quality of Life; D057566:Self Report
chemical_list: D007785:Lactose