Depression is the most costly among 10 common risk factors linked to higher health spending on employees, according to a new study drawn from the experience at seven companies.
The analysis, published in the journal Health Affairs, found that these factors — which also included obesity, high blood sugar and high blood pressure — were associated with nearly a quarter of the money spent on the health care of more than 92,000 workers.
Among common health problems, depression was linked to the highest increase in annual spending by employers' on workers' health care.
First the employees were assessed for health risks, then researchers tracked their medical spending from 2005 through 2009.
The average medical spending for each employee was $3,961 a year. In total, $82 million, or 22 percent, of the $366 million annually spent on health care for the workers was attributed to the 10 risk factors, the study found.
The relationship between higher spending and depression was the strongest, with 48 percent more spending for workers with a propensity for that widespread problem.
People with high blood sugar had medical expenses that were almost one-third higher, as did people with high blood pressure. Obesity was associated with 27 percent more spending.
Tobacco use, sedentary behavior and high stress also were related to increased spending, although not as much as those other risk factors. People with multiple risk factors tended to have the highest health costs.
The study couldn't show that any of these risk factors caused the higher spending, merely that they were related. And the study discovered that three risk factors — high cholesterol, poor nutrition and eating habits and alcohol drinking — were actually associated with slightly lower health spending.
The researchers suggested various explanations for these counterintuitive findings. As for alcohol, they wrote that "the nationally recognized threshold for high risk (three drinks a day for men and two for women) may need to be revisited, because drinking at these levels would not constitute alcohol abuse."
They questioned the usefulness of the way the study measured a nutritious diet, writing it might not be enough to simply measure fruit and vegetable consumption. As for cholesterol, they asserted that its impact on health might be more complicated than a simple causal relationship.
The study was led by Ron Goetzel, director of Emory University's Institute for Health and Productivity Studies and an executive at Truven Health Analytics in Washington, D.C. (Truven and NPR are partners in a regular consumer health poll.)
The researchers said the overall results of the study could offer encouragement to employers to do more to screen workers for high-risk behaviors and get them treatment.
On the question of whether employers might try to screen out prospective employees with these risk factors, the authors said that so many people in the nation have one or more of these risk factors that any such effort might crimp hiring. "More important," the authors wrote, "taking this approach would also be unethical and illegal."