FSSG questionnaire aids in diagnosis of GERD-related cough

Diagnosis of gastro-oesophageal reflux disease (GERD) remains unclear in patients with subacute/chronic cough, especially those with low blood eosinophil counts ≤150/μl, but using the Frequency Scale for the Symptoms of GERD (FSSG) questionnaire may considerably help, suggests a study presented at the recent American Thoracic Society (ATS) 2019 International Conference held at Dallas, Texas in the US.

Of the patients who were included in the analysis, 110 (43 percent) were diagnosed with GERD as a cause of subacute/chronic cough. GERD patients had significantly higher FSSG scores than those without the disease (11.4 vs 6.5). [ATS 2019, A4701/P525]

Sensitivity (75 percent) and specificity (62 percent) of the FSSG for the diagnosis of GERD-related cough were intermediate, with area under the curve (AUC) of 0.71 (cutoff score, 7 points). These increased to 79 percent and 65 percent, respectively, (AUC, 0.74) when confined to blood eosinophil ≤150/μl. The FSSG questionnaire likewise showed an advantage in the selection of comorbid GERD-related cough in patients with cough variant asthma (CVA; cutoff score, 7 points; AUC, 0.74; sensitivity, 83 percent; specificity, 60 percent).

“It may be helpful to suggest comorbid GERD as a cause of subacute/chronic cough in patients with CVA,” according to researchers Kurokawa and colleagues.

To determine the diagnostic utility of the FSSG questionnaire, 312 patients with never or light smoking history (<10 pack-years) who visited a clinic due to subacute/chronic cough between April 2012 and March 2018 were identified. Diagnostic tests, including spirometry and blood analysis, were performed in all patients. Of these, 256 (168 females; median cough duration, 4.3 months) who could examine both the FSSG questionnaire and blood eosinophil counts were examined.

GERD-cough diagnosis was based on the suspicion of classic reflux symptoms, such as heartburn and typical coughing trigger, which includes phonation, rinsing, lying, eating and consumption of certain food. The response to proton pump inhibitors or prokinetic agents confirmed the diagnosis. The authors performed receiver operating characteristic curve analysis to determine the cutoff score for the diagnosis of GERD-cough in patients with subacute/chronic cough.

One of the most common causes of subacute/chronic cough is GERD, and its prevalence has been shown to increase over time, according to the researchers.

In a previous study, the investigators led by Kahrilas endorsed the use of a diagnostic or therapeutic algorithm to address the causes of common cough, including symptomatic reflux, and suggested that physiological testing be reserved for refractory patients being considered for antireflux surgery or for those in whom a strong clinical suspicion exists which requires diagnostic testing. They also stressed that proton pump inhibitors showed no benefit when used in isolation, but lifestyle modifications and weight reduction could help in suspected reflux-cough syndrome. [Chest 2016;150:1341-1360]

“[The] FSSG questionnaire, which consists of acid-reflex and dysmotility symptoms domains, is a succinct questionnaire to evaluate GERD symptoms. It is used to investigate the relationship between respiratory diseases and symptoms of GERD in Japan. However, its utility for the diagnosis remains unclear in patients with subacute/chronic cough,” the researchers noted.