Reflux drugs (PPIs) strike again

Hospital-Acquired Pneumonia
A new study from the European Respiratory Journal reaffirms that proton pump inhibitors (PPIs) are tied to a higher risk of community-acquired pneumonia (CAP). In a population-based case-control study of 430 adults with CAP and 1,720 matched controls, initiation of PPI therapy within the past 30 days was associated with about a 3-fold increased risk of CAP

Prior studies have suggested that backflow and overgrowth of gastrointestinal bacteria during PPI therapy may result in colonization of the oral space and predispose to pneumonia. The current study was the first to include elaborate microbial data, acquired using an extensive diagnostic protocol to identify the causative agent of CAP.

A Canadian Medical Association Journal study also links the use of acid-suppressive drugs to increased risk for pneumonia. Overall risk for pneumonia was higher in persons taking proton pump inhibitors and in those taking histamine-2 receptor antagonists. The findings suggest that 1 of every 200 inpatients treated with acid-suppressive drugs will develop pneumonia, which is even more clinically meaningful given that 40% to 70% of hospitalized patients receive these medications.

Allergy
An important feature for oral allergens is their digestion-resistance during gastrointestinal transit. For some oral allergens, digestion stability is an innate feature, whereas digestion-labile antigens may only persist in times of impairment of the digestive system. Gastric acid levels determine the activation of gastric pepsin and also the release of pancreatic enzymes. When anti-ulcer drugs inhibit or neutralize gastric acid, they allow persistence of intact food allergens and protein-bound oral drugs with enhanced capacity to sensitize and elicit allergic reactions via the oral route. Further study suggests that maternal food allergy arising from co-application of a food protein with anti-acid drugs results in a Th2-biased immune response in the offspring. Especially, anti-ulcer drugs containing aluminum compounds act as Th2 adjuvants. In summary, impairment of gastric function is a documented risk factor for sensitization against oral proteins and drugs. Allergy, April 2011