lunes, 15 de diciembre de 2008

Gastroesophageal reflux disease - information for primary care physicians

Gastroesophageal reflux disease (GERD) is a very common health problem, and family doctors have been exposed to a vast array of literature recently on the topic, as well as a massive promotion of anti-reflux drugs by the Pharmaceutical Industry. As such, it is difficult not to be a little bit complacent about the issue when almost everything seems to have already been told about it.
This article is a review article from the New England Journal of Medicine published on 16 October 2008: N Engl J Med 359;16

GERD, in the light of the latest scientific evidence, is an overlooked and is far from being a straightforward affair; it currently faces a number of controversies surrounding its diagnosis and management. In other words, GERD is way much more than endoscopy and proton pump inhibitors, and a lot remains to be known and understood about this disease.
One of them is the not so perfect correlation between clinical symptoms and endoscopic findings, as only around 40% of individuals with Barrett’s esophagus and a third of indivuals with esophagitis reported having symptoms. Additionally, two-thirds of individuals with symptoms had no endoscopic signs of esophagistis.
The implications of this is that we may be overestimating the added value of endoscopy, while overlooking the need to investigate other cause of dyspeptic symptoms, namely cardiac, as well as referring patients for other examinations which may be turn out to be more appropriate, like esophageal manometry or ambulatory pH monitoring.
It is also important not to forget the often overlooked extraesophageal syndromes, which are well pointed out in table 1.

In terms of therapeutics, the value of Proton Pump Inhibitors (PPI) is unquestionable, as well as their superiority over H2-blockers and placebo. The differing response of esophagitis and heartburn to PPI is less known, since the studies show that they are more effective in treating the symptoms of esophagitis rather than heartburn. The author attributes these differences to the heterogeneity of study populations in the studies, and to the fact that the outcome measures in most trials of PPI were a complete resolution of symptoms rather than substantial improvement. Don’t forget as well, like I said above, that heartburn is pretty much an unspecific symptom, with another potential aetiology other than gastrointestinal, and which thus does not respond to PPI.

It is also worthy reviewing the side effect profile of PPI, since it is one of the most prescribed class of drugs in primary care, and fiercely promoted by the drug industry.
The most common side effects are headache, diarrhoea, constipation, and abdominal pain. Furthermore, its long term use is associated with potentially serious consequences in the long run, such as an increased risk of hip fracture due to interference in the calcium metabolism, infectious gastroenteritis, and Clostridium difficile colitis.

It is also curious to note that fundoplication surgery seems also to be more effective in treating esophagitis rather than heartburn. Moreover, the rate of recurrent esophagitis hasn’t differed much in studies assigning a treatment arm for PPI and another for fundoplication. It is worthy to take note that besides the inherent morbidity associated with any surgery, a procedure such as Nissen fundoplication increases the risk of severe dysphagia, flatulence, inability to belch, diarrhoea, bloating, abdominal pain and constipation. Not to mention the significant rate of need of undergoing a new operation and to continue on PPI therapy after the surgery.
Surgery, should therefore, be considered very carefully, since it has not been proven to be much better than standard medical therapy, and carries a long list of morbidity and complications. The interesting bit is that around 2 in 3 patients will continue to require long-term PPI, and the risk of developing Barrett’s oesophagus or oesophageal adenocarcinoma is the same in populations of patients who have just received either medical or undergone surgery.
Since surgery has been losing popularity, this may mean that more patients with dyspeptic complaints may end up receiving medical care from primary care physicians than by surgeons from now on than it the past. Additionally, the author does not state which types of patients will tend to benefit more from surgery rather than with medical therapy alone, so I would reckon that primary care physicians should privilege medical therapy, and discuss the need for surgery in complicated, PPI refractory cases, with general surgeons in the local hospital.

The author has also approached the current controversy surrounding the indication for endoscopy in patients with chronic symptoms of GERD, so as to screen for Barrett’s oesophagus, which as we all know, increases tremendously the likelihood of having oesophageal adenocarcinoma. The Canadian guidelines do not recommend screening endoscopy, a view shared by the American Gastroenterological Association, which also does not recommend against endoscopy. The American College of Gastroenterology takes a more liberal stance, and supports endoscopy in cases of patients with “symptoms suggesting complicated disease”, namely dysphagia, odynophagia, bleeding, weight loss, anemia, those at risk for Barrett’s esophagus, and when the patient and the physician feel it is appropriate. These indications of the American College of Gastroenterology.
With such discrepancies in the air, particularly from organizations from the same country (United States), it might be a good idea looking first at your national or local guidelines, if available, particularly if you are working in either Spain or Portugal.

The author of this article concludes by giving his own take on this controversy, which seems to be in line with the recommendations of the American College of Gastroenterology. Dr Kahrilas states that in his practice he usually just requests an endoscopy to patients with GERD referring symptoms of odynophagia, gastrointestinal blood loss, anemia or dysphagia, since he considers that patients with GERD have a low absolute risk of developing oesophageal adenocarcinoma, and that there is insufficient evidence in terms of improved survival or a decreased rate of death.

This article is important for primary care physicians, because it is such a “staple” issue of our practice, and we seem to be pressing the same button over and over again, as we get the feeling that everything has already been said about GERD. Maybe not.
Don’t forget also that proton pump inhibitors are one of the most prescribed class of drugs, and that they carry side effects which junior doctors are often not familiar with.
Peter Kahrilas raises many other interesting issues in this article which are of utmost relevance to primary care. These issues include the awareness that it is important to have a sound clinical judgement in order to tackle the gap between symptoms and clinical findings, whereby patients may have symptoms but not any endoscopic injuries, and the situation where patients have no complaints but have endoscopic injuries.
Additionally, it is important to acknowledge that there isn’t a consensual evidence based opinion regarding the need to screen patients with GERD for the presence of Barrett’s esophagus, in order to reduce the risk of esophageal adenocarcinoma. As such, it might be appropriate to discuss this issue with the patient so as to reach a mutual decision.

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