your connection to The Boston Globe

Chronic illnesses on rise, study says

Children's cases in US quadruple

The number of American children with chronic illnesses has quadrupled since the time when some of their parents were children, portending more disability and higher health costs for a new generation of adults, a study said.

An almost fourfold increase in childhood obesity in the past three decades, twice the asthma rates since the 1980s, and a jump in the number of attention deficit disorder cases are driving the growth of chronic illnesses, according to researchers at Harvard University . The study is published in a themed issue of today's edition of the weekly Journal of the American Medical Association that focuses on children's health.

Doctors and public health officials should be bracing for a wave of chronically ill young adults with weight-related ailments that include diabetes and heart disease, researchers said. In 1960, just 1.8 percent of American children and adolescents were reported to have a chronic health condition that limited their activities. In 2004, the rate rose to 7 percent .

"We will see much greater expenditures for people in their 20s than we ever saw before, and no one is thinking how we should prepare for that," said James Perrin, professor of pediatrics at Harvard Medical School and the report's lead author, in an interview. "We call it an epidemic. It's certainly worrisome, and we look at it as a call to action."

The journal's reports also included findings that family based weight-management programs work best, that white children have the highest rate of diabetes, that childhood cancer survivors face risks for serious health problems when they become adults, and that children with serious illness are more likely to die at home now than in 1989.

About 18 percent of children in the US are obese, up from 5 percent in 1974, the study said. Obesity accounts for about 10 percent of US health costs.

"An estimated 60 percent of 5- to 10-year-old obese children already have one associated cardiovascular disease risk factor, and more than 20 percent have two or more risk factors," researchers said in the report.

An estimated 9 percent of children have asthma, twice the rate it was in the 1980s. The breathing disorder persists to adulthood in about a quarter of children.

Attention deficit hyperactivity disorder, not recognized as a medical condition in 1968, is now diagnosed in about 6 percent of school-age youngsters. Research suggests that half of the children with ADHD continue to have it as adults.

Genes may play a role in obesity, asthma, and ADHD, but environmental and social changes are behind the surge, researchers said. Modern life has brought more fast-food , increased time spent indoors watching television or playing on the computer, and dwindling community and family support.

"These three conditions -- obesity, asthma, ADHD -- overwhelm all other chronic conditions," Perrin said.

"The life of the family practitioner is very different than it was. Far more children come in with the type of chronic health problems we hardly thought about 35 years ago."