The new study led by Dr. Linda Ganzini, from Portland Veterans Affairs Medical Center showed a loophole into the Death with Dignity Act was passed by the state in 1997. Researchers say that the Oregon's physician-assisted suicide law may not adequately protect the one in four terminally ill patients with clinical depression.

Researchers studied the data collected from 58 state residents with a terminal illness, usually cancer or ALS. These study subjects had requested assistance in dying, either directly from a physician or through an advocacy organization. 

Researchers identified 15 people with depression and 13 with anxiety using standard measures, including the structured clinical interview of the Diagnostic and Statistical Manual of Mental Disorders.

By the end of the study 42 people died, including 18 who had received a prescription for a lethal drug. Only 3 of the 18 individuals met criteria for depression and all three died from lethal ingestion within 2 months of the study survey. 

After analysis of data, researchers concluded that the Death with Dignity Act does not always prevent patients with depression, a treatable condition, from receiving a prescription for a lethal drug. 

Dr. Linda Ganzini said that the findings indicate that "most people in Oregon who request physician aid in dying do not have clinical depression," but yet there are "small number of patients with clinical depression who are able to access lethal medications". 

She explained that the Oregon law requires that if the prescribing physician is concerned that the patient might have depression influencing their judgment, that they be evaluated by a psychiatrist or psychologist. The proportion of requesting patients who are evaluated by a mental health professional has been dropping over the last decade and last year no mental health assessments occurred among the 46 people who died by physician-assisted suicide in Oregon.

Researchers concluded that physicians need to do a better job in screening for depression among terminally ill patients who wish to die. 

Dr. Marije L. van der Lee, from the Helen Dowling Institute in Utrecht, the Netherlands, wrote in the editorial with research paper that while the current study examined how well depressed patients are protected from assisted suicide, the focus should be on "trying to prevent patients from becoming depressed in the first place."