Eighteen studies were included (at least 21,000 patients with GERD received PPIs). There were 17 RCTs and 1 non-randomised study with no control group.
Fourteen studies scored 3 or more for quality out of a maximum of 5 on the Jadad scale. Fifteen studies were double-blinded.
At day 1 of PPI treatment, complete 24-hour relief of heartburn occurred in 0.31 (95% CI: 0.30, 0.32; based on 13,980 patients), daytime relief in 0.49 (95% CI: 0.48, 0.50; based on 7,497 patients), night-time relief in 0.55 (95% CI: 0.53, 0.56; based on 9,479 patients) and sustained heartburn relief in 0.21 (95% CI: 0.20, 0.22; based on 11,197 patients).
The proportion of maximal response (response at day 28) achieved in the first 24 hours was 0.37 (95% CI: 0.35, 0.39; based on 3,819 patients).
Placebo was significantly less effective than PPI for 24-hour relief on day 1 (RR 0.41, 95% CI: 0.29, 0.58).
Single-dose PPI treatment was significantly less effective than double-dose PPI for 24-hour heartburn relief on day 1 (RR 0.82, 95% CI: 0.74, 0.92).
The subgroup analysis showed that omeprazole 20 mg was less effective than lansoprazole 30 mg and esomeprazole 40 mg for 24-hour sustained relief on day 1. Lansoprazole and esomeprazole were similarly effective for daytime, night-time and 24-hour heartburn relief. The results were reported.