Here is link to original study: Increased Risk of COVID-19 Among Users of Proton Pump Inhibitors
Almario CV, Chey WD, Spiegel BMR. Increased risk of COVID-19 among users of proton pump inhibitors. Am J Gastroenterol 2020 (pre-print posted online July 7, 2020)
This study shows an association but does not prove that PPIs increase risk of COVD-19. Patients taking PPIs may have other attributes that increase their risk compared to those who are not taking PPIs.
Here is some more information on twitter thread of this topic: