Vital Signs: Oct. 8

Thursday, October 08, 2009

Autism diagnoses rising, U.S. Reports

More than 1 in 100 American children and teenagers may have autism, Asperger's syndrome or a related developmental problem, although such diagnoses often do not hold up, according to a government report released Monday.

The estimate, based on a telephone survey of some 78,000 households and published in the journal Pediatrics, is the highest yet of the prevalence of so-called autism spectrum disorders, which include everything from severe autism to milder social difficulties to "pervasive developmental disorder," a description given to many troubled children.

Nearly 40 percent of the children in the study who were given such a diagnosis grew out of it or no longer qualified for it, the study found. The estimate is based on those whose parents said they were currently struggling with one of the disorders.

Prevalence estimates for autism-related disorders have increased so quickly over the past decade — to 1 in 150 in 2007, from 1 in 300 in the early 2000s — that researchers have debated whether the disorder is in fact becoming more common or is simply diagnosed more often.

The new survey is not likely to settle the question. "This is an excellent study, but what it looks at is the prevalence of the diagnosis, not the disorder," said Dr. Susan L. Hyman, a pediatrician at Golisano Children's Hospital in Rochester. "The next step scientifically is to see whether those diagnoses are being made accurately."

Researchers look at deaths after surgery

Patients are much more likely to die after surgery in some hospitals than in others, and conventional medical wisdom has long attributed the excess deaths to a higher rate of postoperative complications. But a new study contradicts that notion.

Researchers looked at 84,730 people who underwent inpatient surgery at 186 hospitals from 2005 to 2007. They found that death rates varied widely from hospital to hospital, from 3.5 percent to 6.9 percent.

But complication rates did not vary significantly: 24.6 percent of patients at the high-death hospitals experienced complications after surgery, compared with 26.9 percent of the patients at the hospitals with the lowest death rates.

The apparent discrepancy suggests that how a hospital responds to complications may be even more important than the frequency of complications, said the study's lead author, Dr. Amir A. Ghaferi. The report, prepared by the Michigan Surgical Collaborative for Outcomes Research and Evaluation at the University of Michigan, appears in The New England Journal of Medicine.

"A lot of current policies are focused on minimizing complications, and that's helpful," Ghaferi said, but added, "It really behooves us to look at what hospitals are doing once they encounter a complication with a patient in a postsurgical setting."

Men sleep on Mars, women on Venus

Elderly women may complain about insomnia, but they really get more sleep than men their age.

That is the surprising finding of a Dutch study that used monitors and sleep diaries to assess the sleep patterns of almost 1,000 men and women ages 59-97 for six days, and found that the women slept a quarter of an hour longer, on average, than the men.

Yet when men and women were asked about the quality of their sleep, women were more likely to report it as poor.

"What we found is that men completely overreport their sleep — they have a strong tendency to make it sound better than it was," said Dr. Henning Tiemeier, associate professor of psychiatric epidemiology at the Erasmus Medical Center in Rotterdam and principal investigator for the study, published in the Oct. 1 issue of the journal Sleep.

In fact, men did not sleep as well as women, the study found. They reported sleeping seven hours a night, but objective measures, including a monitor on the wrist that measured sleep time, indicated they slept less than six and a half hours. Their sleep was also more fragmented, possibly because they drank more alcohol than the women.

Though women reported more problems with their sleep, their reports were more accurate, Tiemeier said.

Are men just oblivious?