The mental health toll of the coronavirus pandemic is only beginning to show itself, and it is too early to predict the scale of the impact.

The coronavirus pandemic is an altogether different kind of cataclysm — an ongoing, wavelike, poorly understood threat that seems to be both everywhere and nowhere, a contagion nearly as psychological as it is physical. Death feels closer, even well away from the front lines of emergency rooms, and social isolation — which in pre-COVID times was often a sign of a mind turning in on itself — is the new normal for tens of millions of people around the world.

The ultimate marker of the virus’s mental toll, some experts say, will show up in the nation’s suicide rate, in this and coming years. The immediate effect is not at all clear, despite President Donald Trump’s recent claim that lockdown conditions were causing deaths. “Just look at what’s happening with drug addiction, look at what’s happening with suicides,” he said in a press briefing in the White House Rose Garden on Monday.

In fact, doctors won’t know for many months if suicide is spiking in 2020; each death must be carefully investigated to determine its cause. The rolling impact of COVID-19 on these rates give scientists a sense of how extended uncertainty and repeating undercurrents of anxiety affect people’s will to live.

“It’s a natural experiment, in a way,” said Matthew Nock, a psychology professor at Harvard. “There’s not only an increase in anxiety, but the more important piece is social isolation.” He added, “We’ve never had anything like this — and we know social isolation is related to suicide.”

The earliest signs of whether the pandemic is driving up suicides will likely emerge among those who have had a history of managing persistent waves of self-destructive distress. Many of these people, who number in the millions worldwide, go through each day compulsively tuned to the world’s casual cruelties — its suspicious glances and rude remarks — and are prone to isolate themselves, at times contemplating a final exit plan.

“That’s how I am,” said Josh, 35, a college instructor in North Carolina who has been consumed in the past with thoughts of suicide. “I see all the bad, the suffering, and I have a tendency to crawl into a hole. Now, with this COVID threat, we’re being told to isolate and stay away from others. It’s like, ‘Oh, I was right all along, and the world was crazy.’”

He added, “I haven’t backslid, I haven’t moved. But longer term — I don’t know.” He asked that his last name be omitted for privacy.

Research done in the wake of natural disasters offers little guidance as to how this group will respond. In a widely cited 1999 paper in The New England Journal of Medicine, researchers from the Centers for Disease Control and Prevention reported that, in communities hit by an earthquake, flood or hurricane, rates of suicide spiked in the years after. But the study authors later retracted that finding, after discovering an error that, when corrected, revealed “no significant increase in suicide rates after natural disasters, either for all types of disasters combined or for individual types of disasters.” Other studies have found increases, or decreases, depending on the group and disaster studied.

The evidence is stronger when it comes to the impact of economic hardship. Suicide rates in the United States have risen steadily since 2000 — by 35% overall, across most age groups — but the rate of increase roughly doubled in the wake of the 2008 downturn. Historically, the job losses, evictions and displacements caused by recessions tend to lead to an increased numbers of suicides.

“I think during the actual crisis, suicide will be lower,” said Dr. Marianne Goodman, a psychiatrist at the Department of Veterans Affairs, in the Bronx. “And once the longer-term economic impact is felt, I suspect, suicide will be rising again.”

But the imminent threat of a potentially deadly virus is very different, psychologically, from the exhausting anxiety of facing a future with few job prospects. The descent of a pandemic alters the thinking and behavior of distressed people in ways that are simply not well understood.

For now, many people who have had to manage self-destructive thoughts have found that their inner dialogue has shifted since the pandemic descended.

“I was in relatively good place when this started, and I think one of the reasons I’ve stayed that way is that, having had all this experience with depression and anxiety, you learn a lot of skills that are applicable in this pandemic,” said Michelle, 37, a New York teacher with a history of chronic suicidal tendencies, including two attempts.

“It’s interesting, I’m having conversations where everyone is feeling anxious about the same thing,” she said. “It’s been a while — since grad school, I think — that I have been a part of conversations like that, and it’s strangely nice.”

In a continuing study, a research team led by Nock is monitoring smartphone data of highly suicidal people for six months after they present in a hospital at risk of suicide. The team has gathered thousands of surveys from people 12 years and older. “From before to after COVID-19, we’re seeing increases in suicidal thinking, among adults, that are predicted by increases in feeling isolated,” Nock said. But preliminary results suggest that such thoughts are not more frequent among the high-risk adolescent, for reasons the team is trying to work out.

The relationship between suicidal thoughts, which are fairly common in people with mental health diagnoses, and completed acts, which are comparatively rare, remains a subject of intense study. A fear of infection may push over the edge some people who would otherwise manage.

Dr. Makeda Jones, a New York psychiatrist, said that a colleague recently called because her teenage daughter tried to hang herself. “For some people who have not learned the skills to cope, this pandemic makes them feel more vulnerable and out of control,” Jones said. “And those two things will make some want to seize back control and say, ‘I don’t want to die of this disease, I can do it on my own terms.’”

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