"We sought to investigate whether higher doses of analgesic drugs, specifically acetaminophen, non-steroidal anti-inflammatory drugs (NSAIDs), and aspirin, increase a woman's risk of developing new-onset high blood pressure," said lead author John Phillip Forman, M.D., instructor in medicine, Harvard Medical School, and associate physician, renal division, Brigham and Women's Hospital, Boston, Mass. "Because high blood pressure is among the most important causes of death and disease in the United States, and analgesics are the most frequently used medications, a relationship between the two would be important from a public health standpoint."
Researchers studied 1,903 women ages 51-77 who participated in the first Nurses' Health Study, and 3,220 women ages 34-53 from the second Nurses' Health Study. The women did not have high blood pressure when the studies began.
Researchers gathered information about whether the women used analgesic drugs, which type, how much, and why they used them, then tracked whether they subsequently developed high blood pressure. The NSAIDs taken were mostly ibuprofen and naproxen.
"In our study, women who took 500 milligrams (mg) or more of acetaminophen per day, on average, were about twice as likely to develop high blood pressure as women who did not use acetaminophen," Forman said.
"In addition, older women (ages 51-77) who used an average of 400 mg or more per day of ibuprofen were about 80 percent more likely to develop high blood pressure compared to older women who did not use this drug. Younger women (ages 34-53) who used more than 400 mg/day of ibuprofen had a 60 percent higher chance of developing high blood pressure," he said.
"We did not find that aspirin increased women's chances of developing high blood pressure," he added.
According to the researchers, doctors are generally aware that NSAIDs have the potential to increase women's blood pressure. However, acetaminophen is perceived as a safe drug without significant effects on blood pressure.
The researchers suggest that these results call for greater caution among women using acetaminophen, ibuprofen and naproxen and more research to investigate the blood pressure effects of acetaminophen.
"More research is needed to confirm our findings," Forman said. "It is important to emphasize that our study is not proof that these drugs will raise blood pressure in all women. Rather, women and their doctors should use caution when using these drugs."
The study was funded with grants from the National Heart, Lung, and Blood Institute; The National Institute of Diabetes, Digestive, and Kidney Disease; and The National Cancer Institute.
Co-authors are Meir J. Stampfer, M.D., Dr.P.H., and Gary C. Curhan, M.D., Sc.D.
Statements and conclusions of study authors that are published in the American Heart Association scientific journals are solely those of the study authors and do not necessarily reflect association policy or position. The American Heart Association makes no representation or warranty as to their accuracy or reliability.