Digestive Diseases and Sciences

, Volume 61, Issue 1, pp 208–214 | Cite as

Correlation Between Capillary and Venous Blood Glucose in the Lactose Tolerance Test

  • José Luis Domínguez JiménezEmail author
  • Antonio Fernández Suárez
Original Article



The lactose tolerance test is a classic method for the study of lactose malabsorption. However, the methodology used has not been standardized, and this leads to differences in results.


The aim of this report was to analyze whether capillary blood glucose measurement is in agreement with venous blood glucose when performing lactose tolerance test.


This is a prospective study of consecutive patients with suspected lactose malabsorption who had lactose tolerance test performed in venous and capillary blood simultaneously, using a load of 50 g lactose. Agreement was measured using the concordance correlation coefficient of Lin (95 % CI) and Bland–Altman plots. The degree of agreement was measured using the Kappa index. A value of p < 0.05 was considered statistically significant.


Eighty-four patients (68 % women) were included. The concordance correlation coefficient showed very poor agreement between the two techniques: 0.68 (0.58–0.77), 0.72 (0.62–0.8), and 0.77 (0.69–0.83) for baseline, 30, and 60 min, respectively. The Bland–Altman plots showed that capillary blood glucose measurements result in higher levels than venous blood glucose measurements, with mean differences of 0.39, 0.77, and 1.1 mmol/L at baseline, 30, and 60 min, respectively. The degree of agreement was low, with a Kappa index of 0.59 (p < 0.001).


The test measured in venous blood is not in agreement with the measurement obtained from capillary blood. It is likely that the diagnostic accuracy attributed without distinction to lactose tolerance test in different studies for lactose malabsorption is incorrect, making it necessary to specify the analysis method.


Lactose tolerance test Lactose intolerance diagnosis Lactose malabsorption Glycemic variability 



Lactose intolerance


Lactose malabsorption


Lactose hydrogen breath test


Lactose tolerance test


Point-of-care testing


Lactose-free diet


Diabetes mellitus


Concordance correlation coefficient of Lin



We appreciate the tireless work of the nursing and medical consultation supporting staff, without which it would have been impossible to conduct this study.

Compliance with ethical standards

Conflict of interest


Informed consent

The protocol was approved by the institutional ethics committee, and informed consent was obtained from all patients.


  1. 1.
    Usai-Satta P, Scarpa M, Oppia F, Cabras F. Lactose malabsorption and intolerance: what should be the best clinical management? World J Gastrointest Pharmacol Ther. 2012;3:29–33.PubMedCentralCrossRefPubMedGoogle Scholar
  2. 2.
    Scrimshaw NS, Murray EB. The acceptability of milk and milk products in populations with a high prevalence of lactose intolerance. Am J Clin Nutr. 1988;48:1079–1159.PubMedGoogle Scholar
  3. 3.
    Suarez FL, Savaiano DA, Levitt MD. A comparison of symptoms after the consumption of milk or lactose-hydrolyzed milk by people with self-reported severe lactose intolerance. N Engl J Med. 1995;333:1–4.CrossRefPubMedGoogle Scholar
  4. 4.
    Johnson AO, Semenya JG, Buchowski MS, Enwonwu CO, Scrimshaw NS. Correlation of lactose maldigestion, lactose intolerance, and milk intolerance. Am J Clin Nutr. 1993;57:399–401.PubMedGoogle Scholar
  5. 5.
    Schirru E, Corona V, Usai-Satta P, et al. Genetic testing improves the diagnosis of adult type hypolactasia in the Mediterranean population of Sardinia. Eur J Clin Nutr. 2007;61:1220–1225.CrossRefPubMedGoogle Scholar
  6. 6.
    Hermida C, Guerra P, Martínez-Costa OH, et al. Phase I and phase IB clinical trials for the noninvasive evaluation of intestinal lactase with 4-galactosylxylose (gaxilose). J Clin Gastroenterol. 2013;47:501–508.CrossRefPubMedGoogle Scholar
  7. 7.
    Shaw A, Davies G. Lactose intolerance: problems in diagnosis and treatment. J Clin Gastroenterol. 1999;28:208–216.CrossRefPubMedGoogle Scholar
  8. 8.
    Domínguez Jiménez JL, Fernández Suárez A. Can we shorten the lactose tolerance test? Eur J Clin Nutr. 2014;68:106–108.CrossRefPubMedGoogle Scholar
  9. 9.
    Alexandre V, Davila AM, Bouchoucha M, et al. Agreement between indirect calorimetry and traditional tests of lactose malabsorption. Dig Liver Dis. 2013;45:727–732.CrossRefPubMedGoogle Scholar
  10. 10.
    Babu J, Kumar S, Babu P, Prasad JH, Ghoshal UC. Frequency of lactose malabsorption among healthy southern and northern Indian populations by genetic analysis and lactose hydrogen breath and tolerance tests. Am J Clin Nutr. 2010;91:140–146.CrossRefPubMedGoogle Scholar
  11. 11.
    Ghoshal UC, Kumar S, Misra A, Mittal B. Lactose malabsorption diagnosed by 50 g dose is inferior to assess clinical intolerance and to predict response to milk withdrawal than 25 g dose in an endemic area. J Gastroenterol Hepatol. 2013;28:1462–1468.CrossRefPubMedGoogle Scholar
  12. 12.
    Plebani M. Does POCT reduce the risk of error in laboratory testing? Clin Chim Acta. 2009;404:59–64.CrossRefPubMedGoogle Scholar
  13. 13.
    Ginsberg BH. Factors affecting blood glucose monitoring: sources of errors in measurement. J Diabetes Sci Technol. 2009;3:903–913.PubMedCentralCrossRefPubMedGoogle Scholar
  14. 14.
    Bruns DE, Knowler WC. Stabilization of glucose in blood samples: why it matters. Clin Chem. 2009;55:850–852.PubMedCentralCrossRefPubMedGoogle Scholar
  15. 15.
    Gambino R, Bruns DE. Stabilization of glucose in blood samples: out with the old, in with the new. Clin Chem Lab Med. 2013;51:1883–1885.CrossRefPubMedGoogle Scholar
  16. 16.
    Lyon ME, Dubois JA, Fick GH, Lyon AW. Estimates of total analytical error in consumer and hospital glucometers contributed by hematocrit, maltose and ascorbate. J Diabetes Sci Technol. 2010;4:1479–1494.PubMedCentralCrossRefPubMedGoogle Scholar
  17. 17.
    Lin LI. A note on the concordance correlation coefficient. Biometrics. 2000;56:324–325.CrossRefGoogle Scholar
  18. 18.
    Corstjens AM, Ligtenberg JJ, van der Horst IC, et al. Accuracy and feasibility of point-of-care and continuous blood glucose analysis in critically ill ICU patients. Crit Care. 2006;10:R135.PubMedCentralCrossRefPubMedGoogle Scholar
  19. 19.
    Savoca R, Jaworek B, Huber AR. New “plasma referenced” POCT glucose monitoring systems-are they suitable for glucose monitoring and diagnosis of diabetes? Clin Chim Acta. 2006;372:199–201.CrossRefPubMedGoogle Scholar
  20. 20.
    Akinbami F, Segal S, Schnipper JL, Stopfkuchen-Evans M, Mills J, Rogers SO. Tale of two sites: capillary versus arterial blood glucose testing in the operating room. Am J Surg. 2012;203:423–427.CrossRefPubMedGoogle Scholar
  21. 21.
    Izquierdo F, Fatela D, Chueca MP. Detección de interferencias y otros errores en la medición de la glucemia en glucómetros portátiles. Recomendaciones 2012. Documentos de la SEQC. Comisión de Interferencias y Efectos de los Medicamentos. Accessed December 2012.
  22. 22.
    Hovde O, Farup PG. A comparison of diagnostic tests for lactose malabsorption—which one is the best? BMC Gastroenterol. 2009;9:82.PubMedCentralCrossRefPubMedGoogle Scholar
  23. 23.
    Newcomer AD, McGill DB, Thomas PJ, Hofmann AF. Prospective comparison of indirect methods for detecting lactase deficiency. N Engl J Med. 1975;11:1232–1236.CrossRefGoogle Scholar
  24. 24.
    Hermans M, Brummer R, Ruijgers A, Stockbrügger RW. The relationship between lactose tolerance test results and symptoms of lactose intolerance. Am J Gastroenterol. 1997;92:981–984.PubMedGoogle Scholar
  25. 25.
    Marton A, Xue X, Szilagyi A. Meta-analysis: the diagnostic accuracy of lactose breath hydrogen or lactose tolerance test for predicting the North European lactase polymorphism C/T-13910. Aliment Pharmacol Ther. 2012;35:429–440.CrossRefPubMedGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • José Luis Domínguez Jiménez
    • 1
    Email author
  • Antonio Fernández Suárez
    • 2
  1. 1.Department of Gastroenterology and Hepatology, Alto Guadalquivir Healthcare AgencyAlto Guadalquivir HospitalAndújarSpain
  2. 2.Department of Biotechnology, Alto Guadalquivir Healthcare AgencyAlto Guadalquivir HospitalAndújarSpain

Personalised recommendations