LETTERS TO THE EDITOR

 

Results of a nation-wide survey on hypolactasia - How is this condition diagnosed and managed in our setting?

Resultados de una encuesta nacional sobre la hipolactasia: ¿cómo se diagnostica y se maneja esta entidad en nuestro medio?

 

 

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Key words: Hypolactasia. Lactose intolerance. Survey. Lactose intolerance diagnosis. Hydrogen breath test.

Palabras clave: Hipolactasia. Intolerancia a la lactosa. Encuesta. Diagnóstico de la intolerancia a la lactosa. Test de hidrógeno.

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Dear Editor,

Lactase is a disaccharidase present in the apical brush border of enterocytes. The lactase activity loss rate (hypolactasia) varies according to ethnic origin, which determines that the prevalence of hypolactasia also varies from one geographic area to the next (1). In Europe, the area with the lowest prevalence of hypolactasia is found in the north-western continent, around the North Sea and in some zones to the south-west of the Baltic Sea (2). The highest prevalence is found in southern Europe.

No recent data are available regarding the prevalence of hypolactasia in Spain since most studies date back to the 1970s (3). In the study performed in Galicia (4) a prevalence of 32.5 % was identified among the pediatric population. In the opposite age-range end resides the study by Varela-Moreiras et al. (5), who detected a prevalence of 36 %.

On the other hand, patients increasingly demand more information and, while centers with experience in the study of hypolactasia and its clinical impact exist in Spain (6-9), gastroenterologists often lack suitable diagnostic methods, hence hypolactasia is still considered a minor illness among digestive conditions despite its high prevalence and potential increase. All these results in the need to analyze the understanding, diagnostic methodology, and treatment skills of Spanish gastroenterologists as regards this disease. It is on these grounds that a descriptive, cross-sectional study was decided upon, based on a clinical practice survey to members of Sociedad Española de Patología Digestiva (SEPD). Through 26 questions topics such as demography, diagnostic methods, treatment, and follow-up were addressed.

A total of 477 gastroenterologists (58.8 % males) with a mean age of 45 years answered the survey. Most participants worked in a third-level, medium sized (200 to 500 beds), university hospital, were MIR-certified digestive system specialists, and had a cumulative experience of at least 10 years in gastroenterology.

Most respondents estimated a nation-wide prevalence between 10 % and 40 % for lactose intolerance; a tendency to think that prevalence is even higher in the international setting was documented.

The most widely used diagnostic study for the diagnosis of hypolactasia was the hydrogen breath test (53.0 %), followed by elimination diet (27.3 %). The availability of hydrogen breath testing seems to condition the use of this diagnostic tool, as availability was uneven among sites. In all, 35.8 % of respondents considered that this test was unnecessary to reach a diagnosis in the presence of suggestive clinical manifestations. This belief was particularly common among less-experienced specialists.

Symptoms most commonly arousing suspicion of hypolactasia included chronic diarrhea/diarrheic evacuations and flatulence/bloating. These symptoms were considered to be superimposable to those of irritable bowel syndrome or functional dyspepsia by most participants.

According to the results, slightly over one half of all diagnosed cases are referred to primary care for follow-up, albeit virtually all patients are given dietary counseling; lactase tablets were recommended to more than half of cases (58.1 %), mainly to be taken occasionally (90.3 %). Vitamin D and calcium supplements were recommended by one fourth of respondents. Half of specialists considered that patients with hypolactasia may keep on taking lactose in small amounts and, to a lesser extent, lactose-containing medications.

To conclude, the analysis of results from this survey shows a high interest in hypolactasia among SEPD members; notable differences in the diagnosis and subsequent management of the condition have been documented, mainly associated to hospital type and years' experience. A unification of diagnostic and management criteria at the national level is now called for.

 

Federico Argüelles-Arias¹, José María Tenías^2*, Francesc Casellas-Jordá³,
Alfredo J. Lucendo^4*and Fernando Carballo-Álvarez^5**
Grupo de Trabajo sobre Intolerancia a la Lactosa, SEPD.
¹Hospital Universitario Virgen Macarena. Sevilla, Spain.
²Hospital La Mancha Centro. Alcázar de San Juan, Ciudad Real. Spain.
³Hospital Universitari Vall d'Hebron. Barcelona, Spain.
⁴Hospital General de Tomelloso. Tomelloso, Ciudad Real. Spain.
⁵Hospital Virgen de la Arrixaca. Murcia, Spain.
^*Comité de Investigación, SEPD.
^**Comité de Excelencia Clínica, SEPD

 

References

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2. Vuorisalo T, Arjamaa O, Vasemägi A, Taavitsainen JP, Tourunen A, Saloniemi I. High lactose tolerance in North Europeans: A result of migration, not in situ milk consumption. Perspect Biol Med 2012;55:163-74.         [ Links ]

3. Guix García J, Rodrigo Gómez JM, Aparisi Quereda L, Serra Desfilis MA, García-Conde Gómez FJ. Lactose intolerance in the Spanish population. Rev Esp Enferm Dig 1974;42:367-82.         [ Links ]

4. Leis R, Tojo R, Pavón P, Douwes A. Prevalence of lactose malabsorption in Galicia. J Pediatr Gastroenterol Nutr 1997;25:296-300.         [ Links ]

5. Varela-Moreiras G, Antoine JM, Ruiz-Roso B, Varela G. Effects of yogurt and fermented-then-pasteurized milk on lactose absorption in an institutionalized elderly group. J Am Coll Nutr 1992;11:168-71.         [ Links ]

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7. Casellas F, Varela E, Aparici A, Casaus M, Rodríguez P. Development, validation, and applicability of a symptoms questionnaire for lactose malabsorption screening. Dig Dis Sci 2009;54:1059-65.         [ Links ]

8. Casellas F, Malagelada JR. Applicability of short hydrogen breath test for screening of lactose malabsorption. Dig Dis Sci 2003;48:1333-8.         [ Links ]

9. Hermida C, Corrales G, Cañada FJ, Aragón JJ, Fernández-Mayoralas A. Optimizing the enzymatic synthesis of beta-D-galactopyranosyl-D-xyloses for their use in the evaluation of lactase activity in vivo. Bioorg Med Chem 2007;15:4836-40.         [ Links ]