EPIDEMIOLOGY OF GASTROINTESTINAL PROBLEMSBy:M. Rum Rahim, MD., MSc.

Suggested Reading:Lipsky, Martin.S., Gastrointestinal Problems, Lippincott Williams & Wilkins. Philadelphia, 2000Yarnell, John., Epidemiology and Prevention: A System-based Approach., Oxford University Press., Oxford New York, 2007

IntroductionThis lecture, the epidemiology of dyspepsia, which is one of the commonest GEH problems presenting in primary care, the diseases associated with Helicobacter pylori infection, & the epidemiology of IBD, cirrhosis of the liver, & abdominal pain in adult

IntroductionThe scope of this subject to discuss the epidemiology of all chronic gastro-intestinal disease. Instead, several important topics have been chosen, which include dyspepsia, because of the substantial health cost associated with this group of symptoms & Helicobacter pylori. This is the most common bacterial infection known to man, & its association with diseases has only recently become known through epidemiological & clinical studies.

DyspepsiaAbdominal Pain in AdultsRAP in ChildrenJaundice in Adults

DYSPEPSIAThe term dyspepsia covers a variety of symptoms affecting the upper gastro-intestinal tract, which include epigastric pain or discomfort, heartburn, acid regurgitation, excessive burning or bleching, a feeling of slow digestion, early satiety, nausea, and bloating. Standardization of the definition of dyspepsia has proven very difficult, & although consensus definition of dyspepsia are available, for example the Rome I criteria, they have not been widely used in epidemiological studies.

THE ROME I CLASSIFICATION OF DYSPEPSIAPain or discomfort centred in the upper abdomenDiscomfort may be characterized by post-prandial fullness early satiery nausea, retching, vomiting, upper abdominal bloating. Patients with symptoms of heartburn & acid regurgitation are considered to be distinct from patients with dyspepsia.

Westbrook, J.L. et al, (2000) The Impact of Dyspepsia Definition on Prevalence Estimates. Scandinavian Journal of Gastroenterology, 3:227-33.

Dyspepsia..PrevalenceA recent systematic review of population-based studies of dyspepsia in developed countries showed substantial variation in the reported prevalence of dyspeptic symptoms, ranging from 8 % to 54 %.

Dyspepsia..Risk Factors are approximately 50% more likely to report dyspeptic symptoms than , & dyspepsia prevalence increases slightly with age until 65 years.Smokers are more likely to have dyspeptic symptoms, especially heartburn & regurgitation, but alcohol consumption in moderate amounts does not appear to be a RF

Dyspepsia..Risk FactorsPsychological factors play an important role both in reporting dyspeptic symptoms & seeking medical attention for these symptoms.Obese people are approximately 3 X more likely to suffer from heartburn & regurgitation but being overweigth is less clearly related to other dyspeptic symptoms.

Dyspepsia..Risk FactorsA recent meta-analysis of randomized controlled trials has confirmed that users of NSAIDs are 3 X more likely to experience dyspepsia than non users. This risk is limited to the use of high doses of any NSAIDs or to any dose of indomethacin, meclofenamate, & piroxicam.

NSAIDs : Non-Steroidal Anti Inflammatory Drugs

Dyspepsia..Time TrendsThe interpretation of trends in dyspepsia is difficult for reason related to the problems of definition, & because of paucity of population based studies before the 1980s. It is clear though, that dyspeptic symptoms have been very common for many years in people living in developed countries. Indeed, Milk of Magnesia was invented as a treatment for dyspepsia by Sir James Murray in Belfast in 1812

Dyspepsia..Time TrendsGastro-oesophageal reflux is a RF for GERD has been increasingly diagnosed in recent decades. Greater use of endoscopy has contributed to the trend in diagnosis of reflux oesophagitis, & data not available to confirm whether this reflects an increase in heartburn and regurgitation in the general population.

Helicobacter pyloriH.pylori is a gram(-) spiral bacterium that infects human gastric mucosa.Approximately 50% of the worlds population are infected by H.pylori, making it the commonest chronic infection worldwide.However, infection rates vary substantially according to geographic region, age, & birth cohort.

Abdominal Pain in AdultsDEFINITIONAbdominal pain is a common problem with a variety of presenting symptoms & potential causes.

Diagnostic possibilities range from the chronic & benign (e.g., IBS) to the acute & life threatening (e.g., ruptured aortic aneurysm)

Abdominal Pain in AdultsPossible causes of abdominal pain in the office setting:Acute gastroenteritisCholelitiasisUTIDiverticulosisPeptic ulcer diseaseAppendicitisIBSUrolithiasisPelvic inflammatory diseaseUlcerative colitisGERDMuscular strain

Abdominal Pain in AdultsRISK FACTORSHypertension & known vascular disease are RF for vascular causes of abdominal pain as well as referred pain from myocardial infarction. In addition, atrial fibrillation is a RF for mesenteric artery emboli.Alcohol use, cigarette smoking, and caffeine use all predispose to the development of GERD. Alcohol use can cause gastritis & pancreatitis. Cigarette smoking has been linked to peptic ulcer disease.

GERD: Gastro Esophageal Reflux Disease

Abdominal Pain in AdultsRISK FACTORSAdvancing age is a RF for development of vascular disease, cholecystitis, & diverticulitis.Hyperlipidemia is a RF for vascular disease & pancreatitis. Triglyceride values greater than 700 mg/dl place the patient at increased risk for pancreatitis, & often the values in patients with pancreatitis are greater than 1000 mg/dl.Obesity or a change in weight can predispose to gallstone formation

Abdominal Pain in AdultsRISK FACTORSMedications have been linked to the development of gastric & duodenal ulcers as well as pancreatitisHypercalcemia, such as occurs with hyperthyroidism, can cause pancreatitis.Abdominal surgery can lead to the formation of adhesion & resultant bowel obstruction. In addition, past history can signify recurrence of disease, such as diverticulitis.

Abdominal Pain in AdultsRISK FACTORSFamily history can play a significant role for patient who develop gallstone, kidney stones, colon cancer, IBS; it may play a role in peptic ulcer disease.In women, abdominal pain may have a gynecologic cause (e.g., ovarian torsion, endometriosis, ectopic pregnancy, & pelvic inflammatory disease). A history of sexually transmitted disease & prior episodes of pelvic inflammatory disease. Women are also at a greater risk of developing cholecystitis

Abdominal Pain in AdultsPATIENT EDUCATIONPatient with pancreatitis should be counseled regarding the potential causes of pancreatitis. If alcohol is a trigger or potential causative factor, then provide information regarding abstinence & resources for substance abuse counseling & support. Patient with acute or chronic pancreatitis who are diabetic will need education regarding their diabetes, including information about a low-fat, diabetic diet, glucose menitoring, & insulin or oral hypoglycemic therapy.

Abdominal Pain in AdultsPATIENT EDUCATIONRecurrent symptoms of abdominal pain or fever should be reported by patients with diverticulitis or appendicitis, as they may signify abscess formation or recurrent diverticular disease. Instruction to increase dietary fiber may be helpful for patient with diverticular disease

Recurrent Abdominal Pain (RAP) in ChildrenDEFINITIONRAP occurs in 10% to 15% of children aged 4-16 years. It is defined as episodic pain that occurs for longer than 3 months & affects normal activity. The pain is real but may be isolated & paroxysmal, accompanied by dyspepsia, or associated with an altered bowel pattern.

Recurrent Abdominal Pain (RAP) in ChildrenDEFINITIONIt is often caused by a functional bowel disorder. The child may refuse to go to school or be sent home from school because of persisting pain. Children aged less than 4 years who have chronic abdominal pain require a more detailed evaluation to exclude organic causes.

Recurrent Abdominal Pain (RAP) in ChildrenRISK FACTORSBoys & girls are equally affected up to age 9 years9-12 years 1.5 times more likely to have RAP.Lactase deficiency is most common in Asian, African-American, & Hispanic children.Crohns disease & ulcerative colitis >> in whites, especially those of Jewish descent.

Recurrent Abdominal Pain (RAP) in ChildrenRISK FACTORSG.lamblia infection occurs in travellers who drink contaminated water from mountain streams, but can also occur in institusional settings such as day-care centers.C.difficile enterocolitis has occurred as a result of exposure to almost all antibiotics.

Recurrent Abdominal Pain (RAP) in ChildrenPATIENT EDUCATIONIt is important to reassure the child & parents that major life-threatening illnesses have been excluded by the examination. However, it must be emphasized that the pain that the child is experiencing is real & not just in his/her head. Explain that the reason for the pain is not completely understood, but may be caused by the child being more sensitive to normal GI sensations or to increased GI activity.

Recurrent Abdominal Pain (RAP) in ChildrenPATIENT EDUCATIONThe child should be encouraged to resume normal activity. Parent can comfort & reassure the child, but should avoid actions that reward pain behavior, such as keeping the child home from school. This message should also be conveyed to others involved in the care of the child, including school authorities.

Recurrent Abdominal Pain (RAP) in ChildrenPATIENT EDUCATIONAlso use active listening to encouraged the parent & child to express their fears & concern about

Jaundice in AdultsDEFINITIONJaundice, also referred to as icterus, is a syndrome characterized by hyperbilirubinemia & deposition of bile pigment in the skin, mucous membrane, & sclera that results in a yellowish appearance.

Usually bilirubin level need to be greater than 2.5 to 3.0 mg/dl for jaundice to be visible.

Jaundice in AdultsRISK FACTORSMany RF exist to various disorders causing jaundice. RF for viral hepatitis include multiple sexual partners, IV drug use, travel to endemic area, & prior blood transfusions.Family history may be an important RF in developing alcohol dependency & its associated liver disease.

Jaundice in AdultsRISK FACTORSIt is also a factor in familial disorders such as Gilberts syndrome or hemachromatosis.Dubin-Johnson syndrome & Rotors syndrome are both inherited in an autosomal recessive fashion & there may be a family history of one of these disorders.Patients on multiple medications are also at risk for developing jaundice.

Jaundice in AdultsPatient EducationPatient with jaundice should be advised of their condition. Those with benign hereditary conditions need to be assured that their condition is neither serious nor contagious. However, they should be aware that other family members are at risk for having the syndrome.

Jaundice in AdultsPatient EducationPatients with underlying liver disease should avoid alcohol or medications that an adversely affect their liver function.They should be immunized againts viral hepatitis to avoid concomitant illness that may worsen their condition.

EPIDEMIOLOGY & PREVENTING OF GEH

**********************************