Dyspepsia is a constellation of symptoms referable to the gastroduodenal region of the upper GI tract. Nonulcerative dyspepsia is a term used to describe signs and symptoms of persistent or recurrent dyspepsia that have no identifiable organic cause.

• Functional dyspepsia (FD) is defined as discomfort or pain in the upper abdomen.
• Postprandial distress syndrome is characterized by postprandial fullness and early satiation. It is the most common subtype of functional dyspepsia.

Nonulcer dyspepsia

Functional dyspepsia

Idiopathic dyspepsia

Postprandial distress syndrome (PDS)

Up to 25% of the general population will experience dyspepsia each yr. Of these, 75% will have no evident causative agent. Functional dyspepsia is a common disorder, with an estimated prevalence of 8% to 12% based on Rome IV criteria and up to 40% when less restrictive criteria are used. Data suggest that less than 15% of patients with functional dyspepsia are actually given the correct diagnosis. In the U.S., the diagnosis, treatment, and work absenteeism related to functional dyspepsia have been estimated to cost $18.4 billion per year.

Typical clinical presentation is dyspepsia without findings on physical examination to explain the symptoms.

The etiology and pathophysiology are still unclear. Box 1 summarizes causes of dyspepsia. Research is focused on abnormalities of gastric motor function and visceral hypersensitivity, as well as:

• Helicobacter pylori infection
• Psychosocial factors-associated with anxiety and depression

Risk factors include the following:

• Genetic predisposition: Homozygous GNB3 gene
• Dietary habits such as caffeine, alcohol, or smoking
• Medications such as NSAIDs, calcium channel blockers, methylxanthines, alendronate, orlistat, acarbose, and potassium supplements
• Psychological disorders such as anxiety, depression, somatization, or personal history of childhood sexual or physical abuse

Nonulcerative dyspepsia is diagnosed when all other organic causes have been excluded, including:

• Peptic ulcer disease (PUD)
• Gastroesophageal reflux
• Gastric/esophageal/other abdominal cancers
• Biliary tract disease
• Gastroparesis, including diabetic gastroparesis
• Pancreatitis
• Medications (i.e., NSAIDs, erythromycin)
• Metabolic disturbances (i.e., hypercalcemia, heavy metals, or hyperkalemia)
• Ischemic bowel disease
• Systemic disorders (i.e., eosinophilic gastritis, Crohn disease, sarcoidosis, celiac disease, thyroid disorders)

The Rome IV criteria (Table 1) lists the following factors, which must be present at least 3 mo and first noticed within 6 mo of diagnosis:

• At least one of the following:
  1. Postprandial fullness, or
  2. Early satiety, or
  3. Epigastric pain, or
  4. Epigastric burning
  5. And no evidence of structural disease likely to explain the symptoms

The American Gastroenterological Association, as well as the Maastricht III and the IV European consensus, suggest the following:

• The pattern of symptoms overlaps considerably for all types of dyspepsia; therefore the history and physical should focus on finding specific symptoms that help exclude other causes of dyspepsia.
• Endoscopy should be performed only in patients >55 yr old and in younger patients with alarming symptoms (e.g., weight loss, progressive dysphagia, recurrent vomiting, evidence of gastrointestinal bleeding, or family history of cancer) presenting with new-onset dyspepsia. Findings consistent with diagnosis of nonulcerative dyspepsia are not conclusive, no presence of H. pylori, no signs of gastroesophageal reflux disease, no mucosal inflammation. NOTE: Patients <55 yr old and without any alarming symptoms can be treated without endoscopy.

H. pylori: Laboratory methods include serologic tests, monoclonal stool antigen, or urea breath test.

Controversy currently exists around the long-term use of PPIs. Due to the high association with psychological factors, patients with functional dyspepsia should undergo psychological intervention, even if there is good response to pharmacotherapeutic approaches.

Peppermint and caraway oil may be helpful; however, no definitive trials have been performed.

• In a recent trial among patients with PDS, acupuncture resulted in increased response rate and elimination rate of postprandial fullness, upper abdominal bloating, and early satiation after 4 wk of treatment.

• Referral to gastroenterology if patient has alarming symptoms (such as GI bleeding, dysphagia, odynophagia, unexplained anemia, change in appetite, and weight loss) or when endoscopy is indicated-although controversy exists about the workup of younger patients
• Referral to cardiology if cardiac etiology suspected

Avoid excessive amounts of caffeine, alcohol, smoking, or long-term use of steroids and NSAIDs.

http://www.mayoclinic.org/diseasesconditions/functionaldyspepsia/symptoms-causes/syc-20375709

Approach to the Patient With Dyspepsia (Algorithm, Section III)