The spectrum of pulmonary symptoms due to gastroesophageal reflux.

Most asthmatics have GER, and the evidence is strong that GER plays an important role in some patients who have asthma. Despite sophisticated study methods and technologically advanced diagnostic tests, the results of published studies on mechanisms have failed to provide a diagnostic test with a degree of certainty great enough to identify which patients have GER-induced or GER-exacerbated asthma and which patients will respond to antireflux therapy. The difficulties involved in establishing a definite cause-and-effect relationship between GER and asthma are real. Even positive results on such direct tests as sputum inspection and scintigraphic monitoring, both of which establish reflux into the tracheobronchial tree, do not necessarily establish cause or effect and cannot be used to predict outcomes. Ambulatory esophageal pH testing can suggest, but cannot prove, the diagnosis of GER-induced asthma, and pH testing cannot be relied on safely to make clinical decisions. A trial of a proton pump inhibitor (PPI) is indicated to assess if asthma improves subjectively and objectively, but the dose must be high enough to prevent even silent esophageal acid exposure, and the duration must be long enough to allow for detection of even subtle trends in subjective and objective respiratory improvement. Antireflux surgery remains a therapeutic option and should not be withheld if GER is a reasonable suspect in asthma exacerbations. Although strong opinions have been voiced as to whether or not a good response to PPI therapy predicts a good response to antireflux surgery, the opinions, although logical, are based on personal experience and gut feelings; a good PPI response may not necessarily predict a good surgery response. Opinions suggesting that a poor response to PPI predicts a poor response to antireflux surgery also may seem logical but are not based on clinical data; a poor PPI response may not necessarily predict a poor antireflux surgery response. When the method is found that predicts which patients who have GER and asthma will respond to antireflux treatment, the results could be profound: fewer hospitalizations for respiratory complications, less pulmonary morbidity and mortality, less need for pulmonary medications, less time lost from work, fewer visits to physicians' offices, and less illness associated with corticosteroid therapy. For the present, however, clinical judgment and good sense still are our best friends. It is not unreasonable to urge patients to alter their lifestyle: the huge volume, calorie-dense, high-fat meals eaten before bedtime are not likely to prevent GER or add to their life expectancy.