Functional dyspepsia

Functional dyspepsia (FD) is a common gastrointestinal disorder defined by symptoms arising from the gastroduodenal region in the absence of an underlying organic disease that could easily explain the symptoms. Characteristic symptoms include epigastric burning, epigastric pain, postprandial fullness, and early satiety. FD was formerly known as non-ulcer dyspepsia, as opposed to "organic dyspepsia" with underlying conditions of gastritis, peptic ulcer disease, or cancer.

The exact cause of functional dyspepsia is unknown however there have been many hypotheses regarding the mechanisms. Theories behind the pathophysiology of functional dyspepsia include gastroduodenal motility, gastroduodenal sensitivity, intestinal microbiota, immune dysfunction, gut-brain axis dysfunction, abnormalities of gastric electrical rhythm, and autonomic nervous system/central nervous system dysregulation. Risk factors for developing functional dyspepsia include female sex, smoking, non-steroidal anti-inflammatory medication use, and H pylori infection. Gastrointestinal infections can trigger the onset of functional dyspepsia.

Functional dyspepsia is diagnosed based on clinical criteria and symptoms. Depending on the symptoms present people suspected of having FD may need blood work, imaging, or endoscopies to confirm the diagnosis of functional dyspepsia. Functional dyspepsia is further classified into two subtypes, postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS).

Functional dyspepsia can be managed with medications such as prokinetic agents, fundus-relaxing drugs, centrally acting neuromodulators, and proton pump inhibitors. Up to 15-20% of patients with functional dyspepsia experience persistent symptoms. Functional dyspepsia is more common in women than men. In Western nations, the prevalence is believed to be 10-40% and 5-30% in Asian nations.

Symptoms of functional dyspepsia include epigastric burning, epigastric pain, postprandial fullness (often described as bloating by those who have FD), and early satiety. Food consumption frequently makes symptoms worse. Although functional dyspepsia is typically chronic, the symptoms are generally sporadic, even during periods of severe symptoms.

Those with FD typically refer to early satiety as a vague abundance of gas after eating or discomfort, but in reality, what they truly mean is that they find it difficult to finish a normal-sized meal because they are uncomfortable or feel full.

While nausea and heartburn are still possible co-occurring symptoms, they are no longer regarded as major dyspeptic symptoms and may originate from different processes. When certain symptoms occur, such as vomiting, a coexisting or alternative condition, like gastroparesis, needs to be evaluated.

Functional dyspepsia has a wide range of complex etiologies. Gastric motor function abnormalities have long been linked to functional dyspepsia. However, a study revealed that there was no relationship between symptoms and stomach physiological abnormalities. The symptoms are significantly influenced by meal consumption, and genetic factors may also play a part.