Depression Eclipses Other Chronic Disease for Poor Health Status

September 7, 2007

GENEVA, Switzerland -- No individual chronic disease - not angina, not arthritis, not asthma, not diabetes -- is more disabling than depression, according to a World Health Organization study.

GENEVA, Switzerland, Sept. 7 -- No individual chronic disease -- not angina, not arthritis, not asthma, not diabetes -- is more disabling than depression, according to a World Health Organization study.

In the World Health Survey of 245,404 patients ages 18 and older, from 60 countries in all regions of the world. respondents with depression had the lowest health score among all five chronic disease conditions, 72.9 (P

The researchers developed a new measure to estimate an individual's health or relative disability. The measure used 18 health-related questions pertaining to general health and disability in working or household activities. This was followed by 12 self-reported health questions including sleep, pain, cognition, self-care, vision, mobility, energy, and interpersonal activities.

A significant percentage of respondents with any one of the chronic physical conditions also had depression. For example, of those with diabetes, 9.3% also had depression. Of those with angina, 15% had depression. Of those with arthritis, 10.7% had depression, while those with asthma, had the highest depression prevalence at 18.1%.

For the 7.1% of respondents who had two or more chronic physical conditions, nearly a quarter (23%) also had depression.

An average of 9.3% to 23.0% of participants with at least one chronic physical disease had comorbid depression, which was significantly higher than the likelihood of having depression in the absence of a chronic physical disease (P

Primary-care providers need to think depression when patients have a chronic physical condition in view of the marked effect it has on an individual's health," they concluded.

In an accompanying commentary, Gavin Andrews, M.D., and Nickolai Titov, Ph.D., of the University of New South Wales in Sydney, Australia, wrote that depression is simple to recognize and not difficult to treat. Yet the burden persists.

If there were a laboratory test to confirm the diagnosis, doctors might be more assertive about insisting that patients adhere to treatment, they suggested.

In Australia, fewer than 30% of patients receive good treatment with antidepressants, cognitive behavioral therapy, and proactive maintenance care. By contrast, 80% of patients with arthritis and 90% of those with asthma receive an acceptable standard of care.

"Perhaps differential access to treatment is one reason why disability is less with the physical disorders. Treatment for depression should at least be on a par with that for other chronic diseases," they concluded.