3.7 billion days lost to illness annually

BETHESDA, Md., Oct. 2 (UPI) -- More than half of U.S. adults have a mental or physical condition that influences functioning resulting in 3.7 billion days per year lost to illness.

Dr. Kathleen Merikangas of the National Institute of Mental Health and Dr. Ronald Kessler of Harvard Medical School used data from the National Comorbidity Survey-Replication, a nationwide survey of 9,282 adults ages 18 and older.

Respondents to the survey were asked how many days they were completely unable to work or carry out their usual activities as a result of problems with their physical or mental health.

The findings, published in the Archives of General Psychiatry, showed that nationwide, about 2.4 billion disability days resulted from the chronic physical conditions -- back pain being the top reason -- and about 1.3 billion disability days resulted from the mental conditions, with depression being the top reason.

"Previous research has found that, on the whole, the least amount of health resources are spent on research and treatment of musculoskeletal disorders and depression, even though these are the most prevalent and disabling conditions," Merikangas said in a statement.