BALTIMORE (WJZ) — Witnessing or experiencing a drug overdose can lead to the development of post-traumatic stress disorder symptoms, a study from the Johns Hopkins Bloomberg School of Public Health found.

The study, which was published last month, focused on 380 female sex workers in Baltimore. Of the 380, more than half reported witnessing a non-fatal overdose, more than one-third saw a fatal overdose and more than 28 percent had experienced an overdose within the past six months.

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More than half of the women also met the criteria for PTSD. Even when accounting for factors like homelessness, intimate partner violence and hunger, the study found overdoses were still “closely linked” with PTSD symptoms.

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“For every overdose fatality, there are even more non-fatal overdoses,” Dr. Kristin Schneider, a postdoctoral research fellow at the Bloomberg School and the paper’s first author, said in a news release. “It’s been unclear what mental health toll these events take on survivors and witnesses, particularly in the vulnerable and marginalized populations that overdose often affects. These findings suggest the consequences are not insignificant.”

The study concluded that more should be done to address the mental health impacts drug overdoses can have on those who see them or experience them.

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“Largely the treatment for overdose has been focused on saving lives. That’s incredibly important, and it should be the first priority,” Schneider said. “But in addition to physical harms, we should also be addressing the enormous psychological harms that accompany overdose to help people fully recover from the trauma in their lives.”

CBS Baltimore Staff