An analysis of over 700 people with suspected reflux who had pH testing revealed that 65.8% (2 out of 3 patients) don’t have the condition. New data from 710 reflux studies across six UK sites show that two‑thirds of patients tested off PPIs had normal acid exposure.
Only 34.2% showed pathological and borderline reflux, underscoring the value of reflux testing and its importance before escalating treatment or considering surgery. 1
Up to 20% of UK adults are thought to have Gastro-Oesophageal Reflux Disease (GORD), but very few are ever sent for formal diagnostics, like pH testing, to confirm reflux,2 A recent survey of 250 reflux patients found that only 8% of NHS patients had been sent for a diagnostic reflux test.3 That means the vast majority of patients are treated on healthcare professionals’ suspicion alone.
The data comes from the Functional Gut Clinic, who provide over 14,000 physiology tests annually, to both NHS and private patients.4 The Clinical Director, Professor Anthony Hobson comments: “In our review of recent reflux studies, just 34.2% of patients showed evidence of acid reflux: 24.1% had definitively pathological AET (acid exposure time) and 10.1% fell within the borderline range.”
“NICE guidance advises doctors to only send patients for reflux testing if they fail an initial trial of PPIs, but still you would expect that most people experiencing typical GORD symptoms – like heartburn, an acidic or sour taste, regurgitation or reflux, swallowing discomfort or pain after eating, belching and nausea – would actually have the condition, as it’s so common. But our data shows the majority don’t have reflux. It suggests that there could be a significant number of patients in the UK who have been misdiagnosed with GORD.”
Under current NICE guidance, reflux testing is generally reserved for patients who fail an initial trial of PPIs. This creates a pathway in which large numbers of patients are funnelled into long‑term medication without confirming the underlying cause of their symptoms. Reflux-like symptoms are estimated to affect 5-10 million people in the UK and most are placed on proton pump inhibitors (PPIs); drugs that now account for 73 million prescriptions a year and cost the NHS around £190 million annually.2
Manchester University NHS Foundation Trust’s Gastrointestinal Medicine Unit is taking a distinctly evidence‑led approach to reflux care. They have one of the highest referral rates for reflux diagnostics in the UK, routinely using 24‑hour pH monitoring, high‑resolution manometry, gastroscopy and 96‑hour capsule pH studies to establish a definitive diagnosis before treatment planning.
Their Clinical Head of Division Mr Paul Goldsmith, an upper GI surgeon with a special interest in reflux, explains: “Prior to any definitive diagnose of reflux in those patients being considered for surgical intervention we send our patients for objective testing. This allows us to get a more accurate diagnosis before a final decision is made. Historically, physiology testing (particularly pH monitoring) wasn’t routinely performed in the UK. In some cases, patients even underwent anti-reflux surgery without ever having had a reflux test. Thankfully, that scenario is now extremely rare.”
“These data reflect what we see in day‑to‑day practice. Many patients referred with a presumed diagnosis of GORD are actually experiencing another condition that mimics reflux such as Small Intestinal Bacterial Overgrowth (SIBO), functional heartburn or oesophageal hypersensitivity; all of which require completely different treatments from acid‑suppression therapy.”
“Even when reflux is confirmed on pH monitoring, it is useful to investigate the underlying cause. A significant proportion of patients with confirmed GORD have structural abnormalities (such as hiatus hernia or impaired sphincter function) which may be better managed with surgical intervention rather than long‑term PPI therapy - around 15% in my experience.”
Some NHS patients are increasingly questioning the accuracy of their reflux diagnosis. In a recent survey of 250 people living with chronic reflux symptoms, 8% believed they had been misdiagnosed — a perception reinforced by the new data.5
References
1. Reflux Confirmed and Excluded in Real-World Outcomes of 24-Hour pH Testing in 710 Patients. Functional Gut Clinic 2026 [Data on file]
2. Vandenbroucke JP, von Elm E, Altman DG, Gøtzsche PC, Mulrow CD, Pocock SJ, et a l. Strengthening the Reporting of Observational Studies in Epidemiology (STROBE): explanation and elaboration. BMJ. 2023;383:e070752. doi:10.1136/bmj-2022-070752 (BMJ: Proton Pump Inhibitors)
3. Patient.info Why you might be mis-prescribed proton pump inhibitors (PPIs)
4. Functional Gut Clinic 2025-26 data (Data on file)
5. Reflux Patient Survey 2025. Commissioned by The Functional Gut Clinic (250 reflux patients). November 2025
