The Link Between Hiatus Hernia and Reflux

How hernia size can affect reflux symptoms and surgical outcomes

Hiatus hernias and reflux often go hand in hand. While not everyone with a hiatus hernia experiences symptoms, for many people, it’s a key reason why reflux persists, even with medication. Understanding how the size of a hernia influences reflux can help determine whether surgery might be the best long-term solution.

What is a hiatus hernia?

A hiatus hernia occurs when part of the stomach pushes up through the diaphragm into the chest cavity. Normally, the diaphragm helps keep stomach contents in place, with the lower oesophageal sphincter (LES) acting as a valve to prevent acid from flowing back up. When a hernia forms, this natural barrier weakens, allowing acid and food to move upwards more easily, causing reflux.

How does hernia size affect reflux?

Small hernias: Small hiatus hernias are common and often cause no symptoms. However, they can still reduce the pressure of the LES, making reflux more likely, especially when lying down or after large meals.

Large hernias:  As a hernia enlarges, a greater portion of the stomach sits above the diaphragm. This changes how the valve works and can lead to more severe reflux. Large hernias may also trap stomach acid in the chest cavity, increasing irritation and inflammation in the oesophagus.

Patients with larger hernias tend to have more persistent symptoms that don’t respond as well to medication alone.

When surgery may be considered

Surgery is usually recommended when:

• Reflux symptoms persist despite medication and lifestyle changes
• There is a large or symptomatic hiatus hernia
• There are complications such as oesophagitis, Barrett’s oesophagus, or narrowing of the oesophagus

The goal of surgery is to repair the hernia and restore the anti-reflux barrier. This is often done through a laparoscopic fundoplication, where the hernia is repaired and the top of the stomach is wrapped around the lower oesophagus to strengthen the valve.

How hernia size influences surgical outcomes

Patients with larger hernias often notice the greatest improvement after surgery because the procedure directly addresses the anatomical cause of their reflux. Smaller hernias can also be successfully repaired, but outcomes are best when both the hernia and reflux mechanism are properly assessed before surgery using tests such as endoscopy, pH monitoring, and manometry.

A hiatus hernia can significantly contribute to reflux symptoms, particularly when it’s large. While medication may control acid, it cannot correct the mechanical issue. If reflux persists despite treatment, specialist assessment and, in some cases, surgery can provide lasting relief and prevent further complications.