cDDDs	Cumulative defined daily doses
GC	gastric cancer
CI	confidence interval
H. pylori	Helicobacter pylori
HMG-CoA	3-hydroxy-3-methylglutaryl-coenzyme A
OS	overall survival
NHIRD	National Health Insurance Research Database
RCIPD	Registry of Catastrophic Illness Patients Database
ICD-9-CM	International Classification of Diseases, Ninth Revision, Clinical Modification
ACE	angiotensin-converting enzyme
NSAID	non-steroidal anti-inflammatory drug
PS	propensity score
HR	hazard ratio
Cag A	cytotoxin-associated gene A
HDAC2	histone deacetylase 2