NU Online News Service, Jan. 9, 2004, 4:47 p.m. EST – The likelihood that a working-age U.S. resident will be disabled increased sharply between 1984 and 2000, according to a study conducted by health economics researchers at the RAND Corp., Santa Monica, Calif.[@@]

The researchers conducted the study by examining results from the National Health Interview Survey, a government survey that collects information from about 36,000 households each year.

The survey identifies people with disabilities by asking participants whether they need help with personal care or other routine needs.

Incidence of disability fell more than 10% for U.S. residents ages 60 to 69, and it rose only modestly for adults in the 18-29 and 50-59 age groups.

But the incidence of disability increased more than 50% for adults in the 30-49 age group, the RAND researchers report.

The researchers found that 182 of 100,000 adults in the 30-39 age group were disabled in 2000, up from a rate of 118 per 100,000 in 1984.

The rate of disability increased to 278 cases per 100,000, from 212 cases per 100,000, for adults ages 40 to 49.

The RAND researchers say the increase in the disability rate for adults in what should be the prime of their lives might be due to factors such as obesity, disability insurance incentives and new medical advances that save people’s lives but leave them with severe disabilities.

The nationwide increase in obesity probably is the most important factor, because that is the only trend comparable in magnitude to the increase in the disability rate, and obesity is linked to problems such as diabetes and chronic back pain, the researchers say.

The incidence of disability caused by both musculoskeletal problems and diabetes increased rapidly between 1984 and 2000, the RAND researchers report.

The RAND researchers say diabetes still accounts for a relatively small percentage of disability claims, but they note that chronic back pain and other musculoskeletal problems are some of the leading causes of disability.