Prevalence Of Lactose Maldigestion Research Articles

Lactose intolerance but not lactose maldigestion is more frequent in patients with irritable bowel syndrome than in healthy controls: A meta-analysis.

Background and PurposeIrritable bowel syndrome (IBS) affects 10%‐20% of the adult population and is characterized by abdominal symptoms without relevant organic disease. There are numerous clinical trials available investigating the relationship between IBS, lactose maldigestion (LM), and lactose intolerance (LI), but there have been no meta‐analyses on this topic yet. We aimed to assess the prevalence of LM, objective and subjective (self‐reported) LI in IBS patients compared to healthy controls (HC) without IBS.MethodsA systematic literature search was conducted up to 24 April 2018 in PubMed, Embase, and Cochrane Library. Adult IBS patients had to be diagnosed according to the Rome criteria or other well‐defined criteria system. We enrolled controlled studies including healthy adult participants without IBS, as control group. Odds ratios with 95% confidence intervals were calculated.Key ResultsAltogether 14 articles were suitable for statistical analyses. IBS patients reported themselves significantly more frequently lactose intolerant than HCs (odds ratio [OR] = 3.499; 95% confidence interval [CI] = 1.622‐7.551). Generally, there was no significant difference in the prevalence of LM based on ingested lactose dose (OR = 1.122; 95% CI = 0.929‐1.356) and test type (OR = 1.156; 95% CI = 0.985‐1.356). However, significantly more IBS patients had objective LI (OR = 2.521; 95% CI = 1.280‐4.965).Conclusions and InferencesLactose intolerance, but not LM is more frequent among patients with IBS compared to HCs. According to our results, IBS among other functional bowel disorders is a possible contributing factor of LI in people with LM.

Self-perceived lactose intolerance and lactose breath test in elderly

BackgroundLactose maldigestion is quite common at all ages. Lactose maldigestion is also common in the elderly but information relative to their symptoms is scarce.Purpose To determine whether in the elderly self-reported lactose intolerance in the normal home setting is comparable to symptoms provoked by a controlled lactose challenge.Design Observational, prospective and transverse study performed in patients referred for a lactose H2 breath test. Material and methodsPatients first completed a validated questionnaire inquiring about symptoms associated with usual consumption of dairy products at home (“home symptoms”). After a 50-g lactose breath test, symptoms score was also obtained. Patients were grouped as absorbers versus malabsorbers (according to the lactose test result) and younger or older than 65years old. ResultsSix hundred and one patients have been included (89 older than 65years old and 512 younger than 65years). Prevalence of lactose maldigestion was the same in both age groups (50% vs 51%). In lactose maldigesters, orocecal transit time and hydrogen excretion capacity after lactose load were independent of age. Oral lactose load induces symptoms in lactose maldigesters. Lactose-induced intolerance symptoms were less intense in elderly than in younger adults (symptoms score of 8 vs 19, P<0.001). Home symptoms were not related to lactose digestion capacity. ConclusionsIn the elderly, lactose maldigestion is associated with increased excretion of hydrogen after oral 50g lactose load but symptoms are less marked than in younger adults. Self-reported intolerance symptoms at home are not clearly related to lactose maldigestion in elderly.

Lactose intolerance and irritable bowel syndrome.

A recent study on lactose intolerance and irritable bowel syndrome has shown that subjective lactose intolerance is increased in patients with irritable bowel syndrome, despite no increase in the prevalence of lactose maldigestion.

Prevalence of Lactose Maldigestion in a Self-Selected Sample of Greek-Cypriots

Prevalence of Lactose Maldigestion in a Self-Selected Sample of Greek-Cypriots

Lactose Intolerance

Lactose maldigestion has been under intensive research since its discovery in the 1960’s. We know the prevalence of lactose maldigestion in a great number of countries and ethnic groups. However, there is often no provision made for the secondary type of maldigestion, and the study populations have sometimes been selected rather than picked at random. New methods for the measurement of lactose digestion have been developed, and its genetic mechanisms have received a great deal of attention during the last few years. However, in many studies the measurement and/or reporting of symptoms has quite often been overlooked. In this review, various topics related to lactose intolerance are discussed with a special emphasis on its symptoms.

Lactose digestion and maldigestion: implications for dietary habits in developing countries

Milk is an important source of high quality protein, energy, calcium, potassium, phosphorus and riboflavin. It also has good functional properties and a highly acceptable taste, making milk a good alternative for the nutrition of children and for food programmes in developing countries. However, in some instances it has been advocated that milk or milk based products might not be appropriate for nutritional support, given the high prevalence of lactose intolerance among populations in those countries. After reviewing studies in different regions of the world it is concluded that: 1. Prevalence of lactose maldigestion in children and adults is significantly reduced, to less than half in most studies, when assessed with a dose of milk similar to that normally taken in the diet, as distinct from a large dose of lactose used in the lactose tolerance test. 2. Lactose intolerance as a result of consuming a glass of milk occurs only in a small proportion (about 30% in most studies) of lactose maldigesters. Even this small group can ingest smaller amounts of milk without adverse symptoms and there is good evidence that colonic metabolism in these people adapts to the presence of lactose to reduce or eliminate adverse symptoms. 3. Lactose maldigestion and intolerance in children in developing countries is more likely to exist in association with gastrointestinal damage associated with diarrhoea, malnutrition and/or infection. 4. There is no evidence to support a reduction or elimination of milk intake for people in developing countries because of lactose maldigestion or intolerance.

Lactose maldigestion and milk intolerance in healthy Greek schoolchildren

The prevalence of lactose maldigestion in Greek adults is 75% but the age at which the lactase activity starts declining is not known. The prevalences of lactose maldigestion and intolerance were investigated in 150 randomly selected Greek children 5-12 y old by using breath-hydrogen analysis after ingestion of lactose (2 g/kg body wt, maximum 50 g) or 0.240 L of milk. Prevalence of lactose maldigestion increased with age (y = -7.30 + 6.49x, r = 0.88, P = 0.004), being 29.4% and 80.0% at ages 5 and 12 y, respectively. Before testing, the reported prevalences of milk-related symptoms by children with high and low lactose-digestion capacity were 21.1% and 39.7% (chi 2 = 5.96, P = 0.015), respectively. However, the corresponding prevalences of lactose intolerance after ingestion of milk were 7.3% and 8.6% (chi 2 = 0.1, P = 0.72) and only three children had a delta H2 greater than or equal to 20 ppm postprandially. Although intestinal lactase activity declines before age 5 y and many Greek children report milk-related symptoms, true malabsorption and intolerance of lactose after a glass of milk is rarely seen at this age.

Lactose Maldigestion

A study was performed to determine whether the age‐related prevalence of lactose maldigestion is increased in healthy institutionalized children. Previous malnutrition did not exclude children from study. The control children had no prior history of malnutrition or hospital admissions for diarrhea. The anthropometric comparison showed the institutionalized children to be shorter and lighter than the controls, but they were of normal weight by stature, suggesting a normal recent nutritional state. Fasting breath hydrogen tests were performed following an oral dose of lactose 1 g/kg, given as a 10% solution. A rise of breath hydrogen of ≥=20 ppm was considered to indicate lactose maldigestion. Twenty‐two of 44 controls and 39 of 49 study children were lactose maldigesters (p &lt; 0.01). The control children showed an age‐related increase in the prevalence of lactose maldigestion, from 31.6% at age &lt;5 years to 75% at age &gt;9 years. The institutionalized children, by comparison had an increased prevalence of 78.8% in the group under 5 years of age (p = 0.002). Equally high prevalence rates were found at all ages tested. At follow‐up, lactose maldigestion was persistent in the majority of the study children. This had no nutritional impact despite a regular milk intake. The distinction between acquired and primary lactose maldigestion is of no practical significance in these children.

Lactose Maldigestion

A study was performed to determine whether the age-related prevalence of lactose maldigestion is increased in healthy institutionalized children. Previous malnutrition did not exclude children from study. The control children had no prior history of malnutrition or hospital admissions for diarrhea. The anthropometric comparison showed the institutionalized children to be shorter and lighter than the controls, but they were of normal weight by stature, suggesting a normal recent nutritional state. Fasting breath hydrogen tests were performed following an oral dose of lactose 1 g/kg, given as a 10% solution. A rise of breath hydrogen of greater than or equal to 20 ppm was considered to indicate lactose maldigestion. Twenty-two of 44 controls and 39 of 49 study children were lactose maldigesters (p less than 0.01). The control children showed an age-related increase in the prevalence of lactose maldigestion, from 31.6% at age less than 5 years to 75% at age greater than 9 years. The institutionalized children, by comparison had an increased prevalence of 78.8% in the group under 5 years of age (p = 0.002). Equally high prevalence rates were found at all ages tested. At follow-up, lactose maldigestion was persistent in the majority of the study children. This had no nutritional impact despite a regular milk intake. The distinction between acquired and primary lactose maldigestion is of no practical significance in these children.

The cut-off criterion for a positive hydrogen breath test in children: a reappraisal.

Seventy-three preschool children with adequate nutritional status underwent interval-sampling, 3-hour breath-hydrogen carbohydrate absorption tests after consuming either 240 ml of intact milk (containing 12 g of lactose) or the same volume of milk with 90-95% of its lactose prehydrolyzed in vitro (containing less than 1 g lactose, with the remaining sugar as glucose and galactose). Results were examined in a reappraisal of the cut-off criterion for the rise of breath H2 concentration signifying biologically incomplete absorption. If the greater than or equal to 10-ppm criterion advocated by some investigators is used, 83% of our subjects would have been classified as incomplete lactose digesters and 30% would have their tests with the monosaccharide-rich milk classified as positive. With the greater than or equal to 20 ppm criterion used in our laboratory and others, the prevalence of lactose maldigestion in the sample becomes 60% and only 4% of subjects have apparent monosaccharide absorption, 96% having a rise below the cut-off level with prehydrolyzed milk. At least in Guatemalan preschoolers, the 20-ppm criterion for a positive breath H2 test provides a superior specificity-sensitivity balance and more reasonable diagnostic conclusions.

The Cut‐Off Criterion for a Positive Hydrogen Breath Test in Children

SummarySeventy‐three preschool children with adequate nutritional status underwent interval‐sampling, 3‐hour breath‐hydrogen carbohydrate absorption tests after consuming either 240 ml of intact milk (containing 12 g of lactose) or the same volume of milk with 90–95% of its lactose prehydrolyzed in vitro (containing &lt; 1 g lactose, with the remaining sugar as glucose and galactose). Results were examined in a reappraisal of the cut‐off criterion for the rise of breath H2 concentration signifying biologically incomplete absorption. If the ≥; 10‐ppm criterion advocated by some investigators is used, 83% of our subjects would have been classified as incomplete lactose digesters and 30% would have their tests with the monosaccharide‐rich milk classified as positive. With the ≥20 ppm criterion used in our laboratory and others, the prevalence of lactose maldigestion in the sample becomes 60% and only 4% of subjects have apparent monosac‐charide absorption, 96% having a rise below the cut‐off level with prehydrolyzed milk. At least in Guatemalan preschoolers, the 20‐ppm criterion for a positive breath H2 test provides a superior specificity‐sensitivity balance and more reasonable diagnostic conclusions.