The Korean Self-evaluation Questionnaire for Functional Dyspepsia

Functional dyspepsia (FD) is a prevalent gastrointestinal (GI) disorder in Korea.¹ Although several symptom generating mechanisms have been discovered, the pathophysiology of FD remains to be elucidated. Clinical outcomes for FD are also not satisfactory. Accordingly, FD leads to a poor quality of life (QOL) and places a heavy medical burden on patients.^2,3 Therefore, relevant clinical and experimental trials continue to be performed. As diagnosis of FD is symptom-based, accurate symptom evaluation is crucial for conducting research successively. Patients need to provide information regarding their feeling, symptoms, and any effects of treatment in a high-quality clinical practice.⁴ Thus, we have recognized the importance of considering patient-reported outcomes (PROs).

Jung et al⁵ have published in this edition of the Journal of Neurogastroenterology and Motility their work that developed and validated a self-evaluation questionnaire for dyspepsia (SEQ-DYSPEPSIA) that is written in Korean, and is easily applicable to Korean patients. The SEQ-DYSPEPSIA is composed of 11 questions mainly addressing the severity and frequency of FD and upper GI symptoms (UGISs) over a 2-week recall period, and is divided into the typical FD, major FD, and other UGISs. Other UGISs were included for the purpose of confirming the overlap or differential diagnosis with other upper GI disorders mimicking FD. Validity was evaluated using the Patient Assessment of GI Symptom Severity Index (PAGI-SYM), Nepean Dyspepsia Index-Korean version (NDI-K), and validated NDI-K QOL questionnaires.

The reliability and validity of the questionnaire was confirmed in a whole (SEQ-DYSPEPSIA) and in subscales with typical FD symptoms (SEQ-typical FD) and major FD symptoms (SEQ-major FD). All questionnaires were reliable and SEQ-DYSPEPSIA showed the highest reliability. In terms of validity, all also highly correlated with the PAGI-SYM postprandial fullness/early satiety subscale, and NDI-K total and dyspepsia subscales. In addition, SEQ-typical FD highly correlated with the PAGI-SYM upper abdominal pain subscale. Furthermore, modest correlation with NDI-K QOL was noticed in SEQ-DYSPEPIA and 2 subscales. In the treatment population, the score of SEQ-DYSPEPIA and 2 subscales was significantly decreased in the responder group than in the non-responder.

The SEQ-DYSPEPSIA seems to be a highly reliable and valid PRO instrument with a good medical responsiveness index in Korean patients with FD. This questionnaire also contains questions regarding not typical but often present symptoms in patients with FD, which may help the PRO obtain their response pertaining to the functional status as well as QOL. In fact, SEQ-DYSPEPSIA showed more statistically meaningful differences in the treatment response evaluation than the PAGI-SYM and NDI questionnaires. Taken all together, SEQ-DYSPEPSIA may be used as a high-quality PRO instrument for Korean patients with FD. It is hoped this tool will play a central role in the clinical practice and research and will lead us to overcome FD in the future.