Background: Gastroesophageal reflux disease (GERD) symptoms bring significant burdens on patients' quality of life. Patient-reported outcome (PRO) instruments for symptoms measurement after treatment is advocated by US Food and Drug Administration. Current tools for GERD symptoms evaluation are limited and the results can be biased by the inaccuracy of patients' recall. To better characterize the GERD symptoms, an e-diary was developed for daily GERD symptom monitoring. We aimed to evaluate (1) the impact of system optimization and symptom severity on the compliance to complete e-diary, (2) temporal trend of GERD symptoms using this PRO-based e-diary.
Method: GERD patients from gastroenterology clinic were invited to fill in the e-diary twice daily for 8 weeks. The e-diary evaluated 8 daytime (acid regurgitation, cough, heartburn, sour taste in the mouth, hiccups, hoarseness, dysphagia, and chest pain) and 2 nighttime symptoms (acid regurgitation and cough) with severity levels (scores from 0 to 5). We evaluated the compliance of e-diary, defined as daily completing rate of e-diary. The e-diary system was optimized from Stage 1 to 3. In Stage 1, no reminder was implemented. In Stage 2, we optimized the system by manually input the mobile numbers into the system by sending out message upon detecting missing e-diary, with a 3-5 day lag between enrollment and mobile number input. In Stage 3, all the mobile numbers were put into the system at enrollment and the system would immediately send out message once missing e-diary detected.
Results: 138 GERD patients (M/F=70/68, 53 years) were recruited and 33.3% of them have coexisted functional gastrointestinal disorders. Incorporating reminding system would significantly increase the compliance (Table 1). More severe GERD symptoms led to a better compliance in completing e-dairy, evidenced by the significant correlations between the severity scores and the completing rate of e-diary at nighttime (r = 0.899, p < 0.001), daytime (r = 0.893, p < 0.001), or overall symptoms (r = 0.894, p < 0.001) (Fig. 1). With treatment, nighttime acid regurgitation prevalence significantly decreased from the 2nd till the 8th weeks (1th, 2nd, 8th week: 34.5%, 27.3%, 20.1%) and nighttime cough significantly decreased from the 4th till 8th week (1th, 4th, 8th week: 24.8%, 15.9%, 13.6%). Improvement in daytime symptoms varied: hoarseness improved from the 2nd week, acid regurgitation and hiccup from 4th week, cough from 5th weeks, sour taste in mouth and heartburn from 7th week, and chest pain from 8th week. Dysphagia didn't get improved.
Conclusions: The compliance of e-diary can be optimized by sending out reminder to patients failed to complete e-diary. GERD symptoms severity was positively correlated with the compliance of e-diary. The response trend in symptoms improvement differs significantly among individual GERD symptoms.

Table 1. The compliance of three stages
Figure 1: Correlation Analysis of Overall Symptom Severity and Patient Compliance