The reputation of the COX-2 inhibitor class of pain-killing drugs, which has come under scrutiny in the wake of Merck & Co’s decision to withdraw Vioxx (rofecoxib) after it was linked to an increased risk of heart attack [[01/10/04a]], has come under the microscope again, this time over claims that it could increase blood pressure amongst users.

According to a meta-analysis of 19 clinical trials including almost 45,500 patients published in the Archives of Internal Medicine, COX-2s cause a rise in blood pressure compared to placebo and non-steroidal anti-inflammatory drugs. Vioxx appears to confer a greater risk of developing hypertension and important elevations in blood pressure compared to Pfizer’s Celebrex (celecoxib).

Although the study authors remain uncertain as to whether this elevation is clinically significant, they note that the effects observed might have most clinical significance in the elderly, in whom the prevalence of both arthritis and hypertension is high. “[COX-2] inhibitors are a welcome addition to the therapeutic options in the treatment of arthritis, which remains a chronic, debilitating, and painful condition,” the study authors noted. “However, their potential (and differential) effect on [blood pressure] elevation requires caution in their use and warrants further investigation. Clinicians need to weigh the risks of improved gastrointestinal safety versus potential hazards of developing elevated [blood pressure] when considering the use of these agents, especially in the elderly population,” they added.