Study challenges proposed changes to clinical definition of mental illness

As the American Psychiatric Association prepares for the Diagnostic and Statistical Manual of Mental Disorders’s fifth edition, there is debate over whether to eliminate milder forms of diseases to prevent overtaxing the mental health care system.

According to Ronald Kessler, HMS professor of health care policy, tightening the DSM’s definitions is a serious matter. His concern is that eliminating the milder illnesses will lead to worse care for patients suffering from those ailments.

To find out how lack of treatment affects people with mild cases of mental illness, Kessler compared the participants’ responses in the National Comorbidity Survey to their responses in NCS’s follow-up study. He looked at people with milder cases of mental illness and found that those participants are twice as likely to develop severe mental illness than those without a mental illness.

Yet the line between mental health and mild mental illness is blurry. “Mental illness operates on a continuum – and there’s not a clear cut off point for when treatment should not be available,” Kessler says.

Kessler admits that it may not be cost-effective right now to treat many mild cases, but he stresses the importance of treating mental illness early.