To Learn How Bone Structure and Bone Mass Change After Long-term PPI Use
Condition: Barrett's Esophagus; Erosive Esophagitis; Gastroesophageal Reflux Disease(GERD)
MeSH terms: Barrett Esophagus; Gastroesophageal Reflux; Esophagitis
Study type: Observational

Summary: 
      Patients with severe acid reflux and/or Barrett's esophagus are recommended to take Proton
      pump inhibitors (PPIs)indefinitely to prevent complications such as strictures or the
      development of a type of esophageal cancer. Recently, some studies suggested that taking
      these medications on a long-term basis may affect the bone. Therefore, it is important to
      learn whether these medications may lead to accelerated bone loss so that effective
      preventive measures can be developed for patients who require these medications for
      acid-related conditions. Several studies reported that patients receiving PPIs for many years
      may have increased risk of hip fractures. However, it is unclear whether this is because the
      PPIs cause reduced bone density or whether the increased risk of fractures has nothing to do
      with PPIs and is because patients who require PPIs have other illnesses that cause the
      increased fractures. The purpose of the study is to learn how bone structure and bone mass
      change after long-term PPI use.
    

Detailed description: 
      Proton pump inhibitors (PPIs) are among the most widely used medications. It is becoming
      increasingly common for patients to take these potent acid suppressants on a long-term and
      continuous basis for erosive esophagitis, Barrett's esophagus and protection against
      nonsteroidal anti-inflammatory drug-related gastropathy. PPI therapy leads to elevated serum
      gastrin levels and may impair the absorption of calcium and food-bound vitamin B12.
      PPI-induced hypergastrinemia has a direct trophic effect on the parathyroid glands, leading
      to parathyroid hyperplasia, increased parathyroid hormone secretion and bone loss.
      Furthermore, both calcium malabsorption and vitamin B12 deficiency are associated with
      reduced bone mineral density (BMD) and increased osteoporotic fracture risk. Consistent with
      these data, recent studies revealed a positive association between PPI therapy and the risk
      of osteoporotic fractures. Peripheral quantitative computed tomography (pQCT) can provide a
      three-dimensional structural analysis of trabecular and cortical volumetric BMD (vBMD) and
      dimensions. These data are imperative for a valid assessment of the effect of chronic PPI
      therapy on bone strength. The investigators hypothesize that PPI therapy leads to decreased
      cortical and trabecular vBMD, cortical dimensions and bone strength.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        -  Patients who either are starting or have been receiving long-term continuous PPI
             therapy for erosive esophagitis or Barrett's esophagus diagnosed within the past three
             years.

          -  Patients who are starting PPI therapy for gastroesophageal reflux disease (GERD) and
             have shown a subjective improvement in symptoms within 4 weeks of starting therapy.
             This improvement will be assessed either through documentation in their medical record
             or through telephone interview with permission from their physician.

          -  Patients who are starting PPI therapy for ulcer prophylaxis in a setting of chronic
             aspirin use.

          -  Patients who are starting PPI therapy for extraesophageal manifestations of GERD.
      
Keywords: Barrett's Esophagus; Erosive Esophagitis; Proton Pump Inhibitor (PPI); Bone; Bone Density; GERD; ulcer prophylaxis