Gastroesophageal Reflux Disease (GERD) Dr. Kairu S. M.
GERD - Definitions Gastro-oesophageal reflux disease (GORD): Abnormal reflux of gastric juice (acid and bile) into the oesophagus leading to symptoms Pathological reflux ranges from simple to erosive to Barrett’s Non-erosive reflux disease (NERD): Reflux disease in which erosion does not occur Heartburn: Burning retrosternal pain radiating upward due to exposure of the oesophagus to acid Oesophagitis: Endoscopically demonstrated damage to the oesophageal mucosa
Prevalence. • Increased prevalence last 10 years. • Accompanied increase in adenocarcinoma lower esophagus. • Obesity associated with increased GERD.
Anti Reflux Mechanism(ARM) • This has both:- (1) Anatomical. (2) Functional.
Anatomical. • The lower esophageal sphincter (LES) at the OG junction consists of tonically contracted smooth muscle at approx. 8-20 mmHg above the gastric pressure. • The outside (extrinsic) compression at the OG junction from the crural diaphragm. • Sharp angle- entry of esophagus into stomach (angle of His).
TLESR (Transient Lower Esophageal Sphincter Relaxations) • A normal phenomenon in healthy individuals. • Dominant mechanism of pathological reflux. • Too frequent TLESRs. • Too prolonged TLESRs.
Functional. • Esophageal peristalsis that serves to clear luminal contents into the stomach. • Secretion and swallowing of saliva to neutralize the acid and enhance clearance. • Prompt Gastric emptying.
bile reflux Pathophysiology of GERD salivary HCO3 Impaired mucosal defence oesophageal clearance of acid (lying flat, alcohol, coffee) Impaired LOS (smoking, fat, alcohol) – transient LOS relaxations – basal tone Hiatus hernia acid output (smoking, coffee) H+ Pepsin Bile and pancreatic enzymes intragastric pressure(obesity, lying flat) gastric emptying (fat)
Heartburn and Regurgitation are the two cardinal symptoms of GERD. • Others:- (1) Dysphagia-due to peptic stricture or peristaltic dysfunction. (2) Chest pain (NCCP). (3) Water brash. (4) Globus Sensation. (5) Odynophagia.
Extra Esophageal Manifestations. • Asthma. • Microaspiration. • Vagal reflex activation. • Laryngitis. • Complications of GERD. • Bleeding. • Stricture. • Barrets esophagus adenocarcinoma
Role of Endoscopy in GERD. • Confirm diagnosis of GERD -erosions/ulcerations. • Diagnose endoscopy-negative reflux. • Exclude other causes of esophagitis/ odynophagia e.g.Candida, Herpes Simplex. • Diagnose complications of chronic GERD e.g Barrets esophagus, stricture, adenocarcinoma.
1.Savary-Miller classification. • Solitary erythematous /erosions covering one mucosal fold. • Solitary erythematous /erosion covering more than one mucosal folds but not circumferential. • Circumferential erythematous / erosions. • Complications • Ulcers. • Strictures. • Barrett’s esophagus.
Modes of Treatment • Proton Pump Inhibitors • Longer acting PPI’s. • Adverse events/effects of PPIs. • Potassium –competitive acid blockers (PCABs) • Motility agents. • GABA agonists • Endoscopic therapy • Full-thickness plication
The Step up Approach. PPI LOW DOSE PB. H2RA +PROKINETIC. H2RA OTC ANTACIDS + LIFESTYLE ADVICE.
The Step Down Approach. • PPI LOW DOSE PB. H2RA +PROKINETIC. H2RA+LIFESTYLE ADVICE. OTC ANTACIDS.
Long Term Therapy. • Many patients, GERD a chronic relapsing problem because the underlying motor abnormalities persist. • PPI’s. • Majority of patients require PPI even in low doses. • Occasional patients may require high doses (double dose of PPI to control symptoms.) • Nocturnal acid breakthrough.
Surgery in GERD Nissan Fundoplication • 40-50% have required medical treatment after surgery. • High failure rate. • Mortality – operatordependent. • Morbidity / complications: ~ 10% dysphagia requiring repeated esophageal dilatation.
Potential Risks of Chronic PPI Therapy • Hypergastrinemia, carcinoids • Gastritis, intestinal metaplasia, gastric cancer • Achlorhydria and loss of gastric sterility • Increased enteric infections, C, difficile. • N-nitrosamine and carcinogen risk • Community =acquired pneumonia • Safety during pregnancy /lactation • Drug interactions.
Potential Risks of Chronic PPI Therapy Hypergastrinemia, carcinoids • RATS • Elevated gastrin • ECL cell hyperplasia • ECL cell carcinoid tumors • HUMANS • Elevated gastrin • ECL cell hyperplasia • NO CARCINOID TUMORS Species specific problem (rat) Up to 8 year continuous use in patients (as of 2000)
Potential Risks of Chronic PPI TherapyAchlorhydria, N-nitrosamine generation The RISK The REALITY • Increased UGI bacteria has been detected in PPI takers. • N-nitrosamine formation is also catalyzed by acid. • Achlorhydria permits growth of bacteria that can convert nitrates to nitrites to N- nitrosamine (carcinogen) Data on PPI use and increased gastric N-nitrosamine remain uncertain and the cancer risk is speculative
Potential Risks of Chronic PPI Therapy Achlorhydria, enteric infection The RISK The REALITY • Achlorhydria disables the gastric barrier to ingested pathogens • Case-control study: Small increase in enteric infections with PPIs for 2 months. • Relative risk 1.6 (Cl 1.0-2.4) • PPPI use is independent risk of C. difficile diarrhea in antibiotic users. • PPI use OR 2.1 (Cl 1.2-3.5) • ≥3 AB OR 2.1 (Cl 1.3-3.4) • Medical ward OR 4.1 (Cl 2.3-7.3) Only occasional cases of enteric infections in patients taking PPI’s have been reported. Garcia Rodriguez LA et al. Epidemiol 1997:8:571-4, Dial S et al CMAJ 2004: 171: 33-8
Potential Risks of Chronic PPI TherapyCommunity –acquired pneumonia The RISK The REALITY • Case-control Dutch primary case database 1/1/95-12/31/2002. • 364,683 Individuals • 5551 1st Pneumonias • PPI user risk 0.60/100 pt yrs • Nested case control analysis to reduce confounding effects of indication • Non-PPI user risk 0.60/100 pt yrs Adjusted OR all 1.27 (Cl 1.06-1.54) • Adjusted OR PPI 1.73 (Cl 1.33-2.25) • Gastric colonization followed by reflux and aspiration of gastric contents results in pneumonia Association does not prove causation PPI takers are also more likely to smoke, drink, be obese, have GERD, and ?? (note how OR 4.08 dwindled to 1.73) Laheji RJ et al. JAMA 2004: 292: 1955-60
Potential Risks of Chronic PPI Therapy Safety during pregnancy/lactation The RISK The REALITY • Omeprazole crosses placenta, category C; Other PPI’s category B • controlled human studies no risk. • animal studies or, adverse fetal. • no adequate studies or, adverse fetal effects in animals at some dose. • evidence of fetal risk: benefit > risk • Evidence of fetal risk: benefit < risk • 1992-2001 prospective controlled evaluation of PPI gestational exposures • Omeprazole: 247 births 3.6% major anomalies. • Lansoprazole: 50 births, 3.9% MA • Pantoprazole: 48 births, 2.1% MA • Controls: 787 births, 3.8%MA European Network of Teratology Information Services…the PPI’s do not represent a major teratogenic risk in humans Diav-Citrin O et al, Aliment Pharmacol Ther 2005: 21: 269-75
PPI’s: Adverse Events/Effects • Clopidogrel • Prospective studies of platelet aggregation. • Retrospepctive studies of clinical outcomes. • Randomized, double-blind trail of PPI vs placebo among clopidogrel users. • No difference in cardiac events, mortality • Significant reduction in GI events with PPI
GABA – β AgonistBaclofen • Baclofen 40mg • Reduced TLESR’s in patients with GERD • Reduced esophageal acid exposure • Limitations • CNS side-effects mainly drowsiness. • Short half-life. Van Herwaarden et al. Aliment Phar,acol Ther 2002
New motility agent (GABA β Agonist)Lesogaberan • Lesogaberan – a peripheral acting GABA β agonist. • Study showed 35% ↓ in TLESR. • A potential agent for treatment of GERD as co-therapy.
Summary • PPI’s remain the standard treatment for GERD. • Well established to be very safe. • Prevalence of GERD increasing with increase in lower esophageal adenocarcinoma. • New motility drugs in development – Lesogaberan.