Observer bias increases likelihood of GERD diagnosis
Published on October 31, 2011 at 10:53 AM
Patients who complain of upper gastrointestinal (GI) symptoms often face a diagnosis of either gastroesophageal reflux disease (GERD) or functional dyspepsia. Because the two conditions often overlap, it can be difficult to distinguish between them and diagnose them properly. Yet ambulatory care facilities and hospitals have reported a dramatic increase in the number of GERD-related visits/discharges in recent years.
“It is worth considering every possible cause of the symptoms, including the sometimes challenging-to-treat functional dyspepsia. Plus, if we believe the patient's symptoms are caused by GERD, we must confirm that diagnosis.”
This led a team of researchers at Mayo Clinic, others from the United States, Europe and Australia to question if "observer bias" plays a role in the diagnosis of GERD, compared to a diagnosis of functional dyspepsia. As reported today during the American College of Gastroenterology 2011 Annual Scientific Meeting and Postgraduate Course, such a bias exists and increases the likelihood of a diagnosis of GERD. This theory is supported by the following findings from the study:
- In the last 20 years, the number of GERD diagnoses has increased despite a simultaneous decrease in GERD symptoms.
- In the presence of both functional dyspepsia and GERD symptoms, GERD is diagnosed most commonly.
- GERD is the most likely diagnosis in the presence of functional dyspepsia symptoms only.
"These findings serve as a reminder to all physicians to keep an open mind when patients complain of upper GI pain," says senior author G. Richard Locke, M.D., a Mayo Clinic gastroenterologist. "It is worth considering every possible cause of the symptoms, including the sometimes challenging-to-treat functional dyspepsia. Plus, if we believe the patient's symptoms are caused by GERD, we must confirm that diagnosis."
The study also found that:
- Between 1985 and 2009, diagnosis rates of GERD rose from 325 per 100,000 patients to 1,866.
- Symptom reporting for GERD actually decreased from 12 percent during the period from 1988 to 1994, to 7.6 percent in 2008-2009.
- Overall functional dyspepsia diagnosis rates rose from 45 in 1985 to 964 in 1999, yet decreased to 452 between 1999 and 2009.
- Functional dyspepsia symptom reporting was stable at around 5 percent throughout the various survey periods.
- The chance of receiving a GERD diagnosis when reporting GERD symptoms was 63 percent, while the chance of receiving an functional dyspepsia diagnosis when reporting functional dyspepsia symptoms was 12.5 percent.
- Forty-five percent of subjects reporting both GERD and functional dyspepsia symptoms were diagnosed with GERD only.
- Fifty percent of subjects reporting functional dyspepsia symptoms only were diagnosed with both GERD and functional dyspepsia.