Belgian researchers are reporting a successful first trial that could change the definition of a stent–the metal tube that is implanted to keep an artery open.
Current stents are implanted permanently to prevent an artery from closing again. But the researchers said they have used a metal stent that is absorbed by the body in a matter of weeks.
“The stent we use is 90 percent magnesium, which you find in normal blood and normal tissue,” said Dr. Marc Bosiers, head of the department of vascular surgery at A.Z Sint-Blasius Hospital in Dendermonde. The other 10 percent is made up of rare earth elements. Eight years of animal tests and a trial with 20 people have shown that the body starts absorbing the stent within a week to 10 days, and the stent is completely absorbed in no more than 60 days, he said. The human trial also showed that arteries that received the absorbable stent were more likely to remain open six months later than with conventional stents, Bosiers said.
A permanent stent can cause chronic inflammation and damage to the blood vessel wall that induces growth of new tissue that eventually reblocks the artery, Bosiers said.
Accident-prone interns
Young doctors-in-training who work the long shifts required by most hospitals are so woozy when they drive home, they run the same risk of a car accident as someone who is legally drunk, a new Harvard study finds.
The nationwide survey of 2,737 interns found the chance of having an accident on the road more than doubled after a work shift of 32 hours, while the risk of a near miss increased nearly sixfold.
Yet “these interns are forced by hospitals to work marathon shifts,” said Dr. Charles A. Czeisler, study author and chief of the sleep medicine division at Brigham and Women’s Hospital, Harvard University’s teaching hospital. “They can’t get a medical license or board certification if they don’t do it.”
The findings appear in the Jan. 13 issue of the New England Journal of Medicine.
Hormone-therapy risk
Hormone therapy has its drawbacks for men as well. A new study has found that older men receiving androgen-deprivation therapy for prostate cancer, an increasingly common treatment for a common cancer, showed an increased risk of bone fracture.
The finding raises the question of whether anything should be done to counteract the therapy’s negative effect.
“The drugs have the appearance of being relatively benign, and we’re trying to say, think about it, for both physicians and patients, that there is a risk to this therapy and that at least should be incorporated into a discussion,” said Dr. Vahakn Shahinian, study author and an assistant professor of internal medicine at the University of Texas Medical Branch, Galveston.
Shahinian and his colleagues analyzed the medical records of 50,613 men age 66 and older. Among the men who had survived at least five years from the date of their diagnosis, 19.4 percent of those who received hormone therapy had a fracture compared with 12.6 percent of those who didn’t. The study appears in the Jan. 13 issue of the New England Journal of Medicine.
