Drug therapies for reducing gastric acidity in people with cystic fibrosis

Drug therapies for reducing gastric acidity in people with cystic fibrosis

BACKGROUND

Malabsorption of fat and protein contributes to poor nutritional status in people with cystic fibrosis. Impaired pancreatic function may also result in increased gastric acidity, leading in turn to heartburn, peptic ulcers and the impairment of oral pancreatic enzyme replacement therapy. The administration of gastric acid-reducing agents has been used as an adjunct to pancreatic enzyme therapy to improve absorption of fat and gastro-intestinal symptoms in people with cystic fibrosis. It is important to establish the evidence regarding potential benefits of drugs that reduce gastric acidity in people with cystic fibrosis. This is an update of a previously published review.

OBJECTIVES

To assess the effect of drug therapies for reducing gastric acidity for: nutritional status; symptoms associated with increased gastric acidity; fat absorption; lung function; quality of life and survival; and to determine if any adverse effects are associated with their use.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic and non-electronic database searches, handsearches of relevant journals,  abstract books and conference proceedings. Both authors double checked the reference lists of the searches Most recent search of the Group's Trials Register: 26 April 2021. On the 26 April 2021 further searches were conducted on the clinicaltrials.gov register to identify any ongoing trials that may be of relevance. The WHO ICTRP database was last searched in 2020 and is not currently available for searching due to the Covid-19 pandemic.

SELECTION CRITERIA

All randomised and quasi-randomised trials involving agents that reduce gastric acidity compared to placebo or a comparator treatment.

DATA COLLECTION AND ANALYSIS

Both authors independently selected trials, assessed trial quality and extracted data.

MAIN RESULTS

The searches identified 40 trials; 17 of these, with 273 participants, were suitable for inclusion, but the number of trials assessing each of the different agents was small. Seven trials were limited to children and four trials enrolled only adults. Meta-analysis was not performed, 14 trials were of a cross-over design and we did not have the appropriate information to conduct comprehensive meta-analyses. All the trials were run in single centres and duration ranged from five days to six months. The included trials were generally not reported adequately enough to allow judgements on risk of bias. However, one trial found that drug therapies that reduce gastric acidity improved gastro-intestinal symptoms such as abdominal pain; seven trials reported significant improvement in measures of fat malabsorption; and two trials reported no significant improvement in nutritional status. Only one trial reported measures of respiratory function and one trial reported an adverse effect with prostaglandin E2 analogue misoprostol. No trials have been identified assessing the effectiveness of these agents in improving quality of life, the complications of increased gastric acidity, or survival.

AUTHORS' CONCLUSIONS

Trials have shown limited evidence that agents that reduce gastric acidity are associated with improvement in gastro-intestinal symptoms and fat absorption. Currently, there is insufficient evidence to indicate whether there is an improvement in nutritional status, lung function, quality of life, or survival. Furthermore, due to the unclear risks of bias in the included trials, we are unable to make firm conclusions based on the evidence reported therein. We therefore recommend that large, multicentre, randomised controlled clinical trials are undertaken to evaluate these interventions.

Drug therapies for reducing gastric acidity in people with cystic fibrosis

BACKGROUND

Malabsorption of fat and protein contributes to poor nutritional status in people with cystic fibrosis. Impaired pancreatic function may also result in increased gastric acidity, leading in turn to heartburn, peptic ulcers and the impairment of oral pancreatic enzyme replacement therapy. The administration of gastric acid-reducing agents has been used as an adjunct to pancreatic enzyme therapy to improve absorption of fat and gastro-intestinal symptoms in people with cystic fibrosis. It is important to establish the evidence regarding potential benefits of drugs that reduce gastric acidity in people with cystic fibrosis. This is an update of a previously published review.

OBJECTIVES

To assess the effect of drug therapies for reducing gastric acidity for: nutritional status; symptoms associated with increased gastric acidity; fat absorption; lung function; quality of life and survival; and to determine if any adverse effects are associated with their use.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic database searches, handsearches of relevant journals, abstract books and conference proceedings.Most recent search of the Group's Trials Register: 12 May 2016.

SELECTION CRITERIA

All randomised and quasi-randomised trials involving agents that reduce gastric acidity compared to placebo or a comparator treatment.

DATA COLLECTION AND ANALYSIS

Both authors independently selected trials, assessed trial quality and extracted data.

MAIN RESULTS

The searches identified 39 trials; 17 of these, with 273 participants, were suitable for inclusion, but the number of trials assessing each of the different agents was small. Seven trials were limited to children and four trials enrolled only adults. Meta-analysis was not performed, 14 trials were of a cross-over design and we did not have the appropriate information to conduct comprehensive meta-analyses. All the trials were run in single centres and duration ranged from five days to six months. The included trials were generally not reported adequately enough to allow judgements on risk of bias.However, one trial found that drug therapies that reduce gastric acidity improved gastro-intestinal symptoms such as abdominal pain; seven trials reported significant improvement in measures of fat malabsorption; and two trials reported no significant improvement in nutritional status. Only one trial reported measures of respiratory function and one trial reported an adverse effect with prostaglandin E2 analogue misoprostol. No trials have been identified assessing the effectiveness of these agents in improving quality of life, the complications of increased gastric acidity, or survival.

AUTHORS' CONCLUSIONS

Trials have shown limited evidence that agents that reduce gastric acidity are associated with improvement in gastro-intestinal symptoms and fat absorption. Currently, there is insufficient evidence to indicate whether there is an improvement in nutritional status, lung function, quality of life, or survival. Furthermore, due to the unclear risks of bias in the included trials, we are unable to make firm conclusions based on the evidence reported therein. We therefore recommend that large, multicentre, randomised controlled clinical trials are undertaken to evaluate these interventions.

Digestive system dysfunction in cystic fibrosis: challenges for nutrition therapy

Cystic fibrosis can affect food digestion and nutrient absorption. The underlying mutation of the cystic fibrosis trans-membrane regulator gene depletes functional cystic fibrosis trans-membrane regulator on the surface of epithelial cells lining the digestive tract and associated organs, where Cl(-) secretion and subsequently secretion of water and other ions are impaired. This alters pH and dehydrates secretions that precipitate and obstruct the lumen, causing inflammation and the eventual degradation of the pancreas, liver, gallbladder and intestine. Associated conditions include exocrine pancreatic insufficiency, impaired bicarbonate and bile acid secretion and aberrant mucus formation, commonly leading to maldigestion and malabsorption, particularly of fat and fat-soluble vitamins. Pancreatic enzyme replacement therapy is used to address this insufficiency. The susceptibility of pancreatic lipase to acidic and enzymatic inactivation and decreased bile availability often impedes its efficacy. Brush border digestive enzyme activity and intestinal uptake of certain disaccharides and amino acids await clarification. Other complications that may contribute to maldigestion/malabsorption include small intestine bacterial overgrowth, enteric circular muscle dysfunction, abnormal intestinal mucus, and intestinal inflammation. However, there is some evidence that gastric digestive enzymes, colonic microflora, correction of fatty acid abnormalities using dietary n-3 polyunsaturated fatty acid supplementation and emerging intestinal biomarkers can complement nutrition management in cystic fibrosis.

Drug therapies for reducing gastric acidity in people with cystic fibrosis

BACKGROUND

Malabsorption of fat and protein contributes to poor nutritional status in people with cystic fibrosis. Impaired pancreatic function may also result in increased gastric acidity, leading in turn to heartburn, peptic ulcers and the impairment of oral pancreatic enzyme replacement therapy. The administration of gastric acid-reducing agents has been used as an adjunct to pancreatic enzyme therapy to improve absorption of fat and gastro-intestinal symptoms in people with cystic fibrosis. It is important to establish the evidence regarding potential benefits of drugs that reduce gastric acidity in people with cystic fibrosis.

OBJECTIVES

To assess the effect of drug therapies for reducing gastric acidity for: nutritional status; symptoms associated with increased gastric acidity; fat absorption; lung function; quality of life and survival; and to determine if any adverse effects are associated with their use.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic database searches, handsearches of relevant journals, abstract books and conference proceedings.Most recent search of the Group's Trials Register: 17 March 2014.

SELECTION CRITERIA

All randomised and quasi-randomised trials involving agents that reduce gastric acidity compared to placebo or a comparator treatment.

DATA COLLECTION AND ANALYSIS

Both authors independently selected trials, assessed trial quality and extracted data.

MAIN RESULTS

The searches identified 39 trials; 17 of these, with 273 participants, were suitable for inclusion, but the number of trials assessing each of the different agents was small. Seven trials were limited to children and four trials enrolled only adults. Meta-analysis was not performed, 14 trials were of a cross-over design and we did not have the appropriate information to conduct comprehensive meta-analyses. The included trials were generally not reported adequately enough to allow judgements on risk of bias.However, one trial found that drug therapies that reduce gastric acidity improved gastro-intestinal symptoms such as abdominal pain; seven trials reported significant improvement in measures of fat malabsorption; and two trials reported no significant improvement in nutritional status. Only one trial reported measures of respiratory function and one trial reported an adverse effect with prostaglandin E2 analogue misoprostol. No trials have been identified assessing the effectiveness of these agents in improving quality of life, the complications of increased gastric acidity, or survival.

AUTHORS' CONCLUSIONS

Trials have shown limited evidence that agents that reduce gastric acidity are associated with improvement in gastro-intestinal symptoms and fat absorption. Currently, there is insufficient evidence to indicate whether there is an improvement in nutritional status, lung function, quality of life, or survival. Furthermore, due to the unclear risks of bias in the included trials, we are unable to make firm conclusions based on the evidence reported therein. We therefore recommend that large, multicentre, randomised controlled clinical trials are undertaken to evaluate these interventions.

Delayed release pancrelipase for the treatment of pancreatic exocrine insufficiency associated with cystic fibrosis

Pancreatic enzyme replacement therapy (PERT) is the only treatment for malabsorption in cystic fibrosis (CF) caused by pancreatic insufficiency (PI). PI occurs in approximately 85% of patients with CF. PERT overcomes some, but not all the signs and symptoms of malabsorption. Clinical parameters such as growth, abdominal pain, diarrhea and gassiness, commonly used to adjust PERT dosing, are shown not to be good indicators of their effectiveness. The FDA does not provide oversight of preparations of pancreatic enzymes consistent with the oversight it provides for all other drugs. The FDA intends to rectify this situation. Measures of the effectiveness of PERT are limited to the coefficient of fat absorption, a difficult and unpleasant exercise for patients.

Gastric acid inhibition for fat malabsorption or gastroesophageal reflux disease in cystic fibrosis: longitudinal effect on bacterial colonization and pulmonary function

OBJECTIVES

To investigate bacterial colonization and pulmonary function longitudinally in patients with cystic fibrosis (CF) receiving drugs for gastric acid (GA) inhibition for fat malabsorption or for gastroesophageal reflux disease (GERD).

STUDY DESIGN

A retrospective cohort study of 218 pediatric patients with CF was performed. Multilevel modeling was used to perform longitudinal analysis of forced expiratory volume in 1 second (FEV(1)), forced vital capacity (FVC), maximum expiratory flow at 50% of FVC (MEF(50)), and maximal mid-expiratory flow between 25% and 75% of FVC (MMEF(25-75)). Cox regression was used to calculate Pseudomonas aeruginosa- and Staphylococcus aureus-free survival.

RESULTS

Patients with CF and GA inhibition had a significantly smaller yearly decline of MEF(50) and MMEF(25-75) compared with control subjects. Other pulmonary function parameters and P aeruginosa or S aureus acquisition or colonization were not different from that of control subjects. GERD was associated with a significantly reduced pulmonary function (FEV(1) and FVC) and an earlier acquisition of P aeruginosa and S aureus.

CONCLUSIONS

GA inhibition did not affect pulmonary function or bacterial acquisition and therefore is not contraindicated in patients with CF. GA inhibition might improve pulmonary function with time, because the decline of MEF(50) and MMEF(25-75) was less pronounced. GERD was associated with a reduced pulmonary function and an earlier acquisition of P aeruginosa and S aureus. Therefore the diagnosis and treatment of GERD should be aggressively pursued in patients with CF.