Blood pressure decreases with apnea treatment, vitamins fail to protect against colorectal cancer, and more news from this week’s medical journals

By Nathan Seppa

Web edition: October 18, 2012
Print edition: November 17, 2012; Vol.182 #10 (p. 17)

Treating apnea improves blood pressure
Strapping on a motorized breathing device before hitting the hay does more than relieve the daytime drowsiness caused by obstructive sleep apnea. A new study finds that many people with the breathing disorder who use the machine at night experience a decrease in blood pressure. Researchers at the University of Illinois at Chicago and the Hines Veterans Affairs Medical Center in Hines, Ill., analyzed medical records of 221 veterans, average age 63, who began using a sleep apnea machine to improve their night breathing. Doing so knocked seven points off their top blood pressure number, on average, and three off the bottom number over three to six months of use, the researchers report in the Oct. 15 Journal of Clinical Sleep Medicine. Blacks saw a substantial decline in both numbers whereas whites had a reduction only in the top number, on average. The study is first to review and document the effect of sleep apnea treatment on blood pressure in a real-world setting, the authors assert.

Psoriasis drug works on some Crohn’s patients
A drug already approved for the skin condition psoriasis also seems to help some people with Crohn’s disease, a form of inflammatory bowel disease. The drug ustekinumab, marketed for psoriasis as Stelara, improved symptoms in more than one-third of people getting it, researchers report in the Oct. 18 New England Journal of Medicine. An international team of scientists randomly assigned 526 Crohn’s patients who had failed to improve with standard medications to get an injection of ustekinumab or a placebo shot. After six weeks, 36.8 percent of patients getting the drug and 23.5 percent of those getting the placebo had shown symptom improvement. The drug inhibits two inflammatory proteins called interleukin 12 and interleukin 23.

No luck predicting depression drug effectiveness
Patients with depression vary widely in how well they respond to medications. Scientists have suspected this arises from inherent genetic differences among people, but a new analysis of more than a half-million common genetic variations finds that none could predict the effectiveness of standard drugs taken by 1,790 people for severe depression. Some patients had taken a serotonin reuptake inhibitor while others got a noradrenaline reuptake inhibitor. Medical records were used to determine how well either type of drug worked, if at all. The scientists, in Europe and Canada, report the findings in the October PLOS Medicine. 

Vitamins fail to prevent colorectal cancer
Multivitamins don’t protect against colorectal cancer, two studies find. In a report released online October 12 in the Journal of the National Cancer Institute, a Boston-based team of researchers finds that in more than 5,000 women, those randomly assigned to get vitamin B6, vitamin B12 and folic acid were no less likely to develop potentially precancerous colorectal polyps than were women getting a placebo. A separate study, whose authors included some of the same researchers, finds that in a group of more than 14,000 men, those randomly assigned to get a multivitamin were no less prone to colorectal cancer than men getting a placebo. That study, reported online October 17 in the Journal of the American Medical Association, found a weak reduction in overall cancer rates in the men getting the multivitamins.