The aim of our study was to examine the association between the use of cardioprotective medications (e.g., beta-blockers, statins, ACE inhibitors, and ARBs) and 90-day mortality, and hospital admission due to cardiovascular events within 90-days, for male patients ≥65 years of age hospitalized with pneumonia using the extensive data of the Department of Veterans Affairs administrative databases. The gene discussed is ACE; the disease is susceptibility to pneumonia measurement.