Non‐cardiac chest pain in Asia: Time for a consensus

Non-cardiac chest pain (NCCP) remains a challenge in diagnosis and management. In the western world, the estimated annual prevalence ranges from 25% to 35%1, 2 and in Asian countries it is between 13.9% and 19.5%.3, 4 Underlying causes and presentation are heterogenous and variable, depending on the patient's country of origin. The article by Hanizam et al. adds to the body of evidence on NCCP,5 highlighting the role of gastro-esophageal reflux disease (GERD, and reconfirming the role of a trial of proton pump inhibitor (PPI) therapy as a first line diagnostic tool and treatment. The community costs associated with NCCP are significant, both in terms of direct costs and indirect costs of forgone productivity. In the US, it has been estimated that NCCP costs approximately USD $8 billion for the initial care of patients suspected to have acute coronary syndrome but subsequently found not to have coronary artery disease.6 Hanizam et al. suggest that, in line with the rising prevalence of GERD in the Asia Pacific region, the prevalence of NCCP is also likely to increase.5 This will result in a concomitant increase in the costs associated with diagnosing and treating NCCP. Therefore it is a matter of urgency that there is a consensus with regards to the investigation and management of NCCP given the increasing scarcity of health dollars. Non-cardiac chest pain is a diagnosis of exclusion, defined as recurrent episodes of retrosternal pain or discomfort in the absence of cardiac disease. In the US, cardiac catheterization is the most common test used to exclude cardiac cause of chest pain.7 Although all patients in the study by Hanizam et al. had an angiogram, in practice, only 11% of cardiologists in the Asian Pacific region would order an angiogram to exclude cardiac causes in patients presenting with NCCP.5, 8 Amongst gastroenterologists and primary care physicians, the preferred cardiac investigation was resting or treadmill electrocardiogram (ECG).9, 10 Since cardiac catheterization is not without risks, perhaps utilization of emergent imaging modalities such as multi-slice computed tomography (CT) angiography could be considered. Once a diagnosis of NCCP is made, the focus shifts towards identifying the underlying cause and treatment of NCCP. The etiology is diverse. GERD has been reported to account for up to 60% of patients,3, 11 which is in keeping with Hanizam et al.'s finding of 67%. At present, after the exclusion of cardiac causes, the suggested best test in the evaluation of NCCP is 24-h esophageal pH monitoring combined with symptom analysis.11-13 However, in practice, endoscopy, PPI test and chest radiograph were most frequently ordered by cardiologists, gastroenterologists and primary care physicians in the Asia Pacific region.8-10 pH studies are not frequently utilized in this region. Patient discomfort associated with pH monitoring and the lack of its availability may contribute to under-utilization of this investigation. The Bravo catheter-free pH monitoring system (Medtronic Inc, Minneapolis, MN, USA)14 utilized in the study by Hanizam et al. is a validated pH monitoring system which may increase acceptability amongst patients and doctors alike. Utilization of the PPI test as both a means of investigation and treatment in NCCP is common in the Asia Pacific region.8-10 Symptom response from the PPI test has been used to identify GERD in SE Asian patients with NCCP with a sensitivity of 92% and specificity of 67%.15 Despite this low specificity, the test can still be of benefit for its ‘placebo’ effect in patient with non-cardiac, non-reflux chest pain.15 However, the optimum duration and dose of the trial of PPI is not known. A recent meta-analysis by our group on the utility of the PPI test found that there was no consensus to the PPI dose, dosing schedule or duration of therapy.16 Cost-effectiveness analysis, however, has shown that the PPI test is cost saving for the evaluation of patients with NCCP.13 In conclusion, Hanimzam et al.'s study highlights the prevalence of NCCP in the Asia Pacific region and that GERD is the leading cause. The study supports the utility of the PPI test as first line investigation and management once cardiac causes have been excluded. Clearly, NCCP poses a diagnostic and management problem in the Asia Pacific region for treating cardiologists, gastroenterologists and primary care physicians alike. The way forward is to move towards a consensus with regards to definition of NCCP, agreement on appropriate algorithms for the investigations needed to substantiate the diagnosis, and management guidelines.