IU researchers study how aging affects adults with Down syndrome

By Richard Doty

While life expectancy of those with Down syndrome has improved dramatically during the past half century, new research shows that cognitive functions begin to decline a decade earlier than those in the general population.

“While life expectancy during the past 50 years has dramatically improved for those with Down syndrome, there are mixed findings regarding the aging process for this population,” said center director Barbara Hawkins, a professor in HPER’s Department of Recreation and Park Administration. Hawkins directed the study with an IU research team that included Susan Eklund, an IU professor of education.

The findings are scheduled for publication later this year in the journal Mental Retardation in an article by Hawkins, Eklund, IU sociologist David James and IU graduate student Alice Foose.

In the area of cognitive functions, Hawkins said, “it appears that an aging-related decline can be identified in these participants with Down syndrome approximately 10 years earlier than in the normal population. On the positive side, in the two areas of auditory processing and comprehension knowledge, growth was shown well beyond age 50.” The study tested areas such as short-term memory and long-term memory.

Down syndrome, which affects more than 350,000 Americans, is a congenital disorder that results in mild to moderate mental retardation, short stature and a flattened facial profile. It is the most frequently occurring chromosomal abnormality.

Hawkins said the study involved nearly 60 adults between ages 31 and 56 when the 10-year study began in 1987. The researchers investigated age-related change in adaptive behavior that deals with personal and community living skills, and cognitive functions such as short-term memory, long-term memory and comprehension.

Hawkins said the research showed an accelerating rate of functional losses in adaptive behavior after age 45 for those with Down syndrome. “These findings suggest the need for programmatic interventions at a younger chronological age that preserve functional independence and active lifestyles through the adult years, particularly for those who are in their late 40s, 50s and 60s,” she said. “These types of health promotion and health protection programs are typical among adults without disabilities between ages 50 and 80.”

The research findings also showed more study is needed to better understand whether declines in adaptive functioning for Down syndrome adults are due to increasing age or to the onset of a serious health problem or disease. “This is a poorly understood process in this population. Continued investigations will help in distinguishing between expected declines with age in adaptive functioning and those that are associated with disease processes in adults with Down syndrome,” she said.