REN and acute kidney injury: It was reported that COX-2 expression in elderly subjects may cause a secondary reduction in basal renin production associated with aging.36 Cyclooxygenase-2 has major importance in healthy volunteers, and rofecoxib, a COX-2 inhibitor, results in blockage of renin and aldosterone secretion.37 Celecoxib is better tolerated in elderly patients, as the risk of acute kidney injury is lower in celecoxib than in rofecoxib.38,39