EDITOR'S NOTE: This story includes discussion of suicide. If you or someone you know needs help, the national suicide and crisis lifeline in the U.S. is available by calling or texting 988.

Nearly 4,400 fewer U.S. teens and young adults died by suicide than projected in the first two-and-a-half years of the 988 mental health crisis hotline, a sign the program is working even as it faces long-term funding challenges.

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Suicide deaths among 15- to 23-year-olds were 11% lower than what researchers expected between July 2022 — when the lifeline launched — and December 2024, researchers wrote in a study published Wednesday in JAMA.

"The 988 program is one of the largest federal investments in suicide prevention in U.S. history — roughly $1.5 billion cumulative — and our findings suggest that investment has translated into measurable reductions in young adult suicide deaths," said Dr. Vishal Patel, a clinical fellow at Harvard Medical School and the paper's lead author.

The researchers used nationwide death certificate records from 1999 to 2022 to model what the suicide mortality would have been had the 988 line not launched. They then compared the estimates to the actual number of deaths.

The researchers can't say for certain that 988 was the sole cause of the decline, and the U.S. suicide rate is down overall. But they ran several other comparisons to "gut check" their overall findings, Patel said.

They found the 10 states that had the largest increases in call volumes following the launch of 988 also saw significantly larger gaps in expected vs. actual suicide deaths. The reductions were also greater in younger people than people older than 65, who are less likely to use the lifeline. And they saw no similar changes when looking at suicide deaths in England, where no comparable lifeline existed during the study period.

The results are in line with previous research.

"Studies show that after speaking with a trained crisis counselor, most people who contact the 988 Lifeline are significantly more likely to feel less depressed, less suicidal, less overwhelmed and more hopeful," a spokesperson for the Substance Abuse and Mental Health Services Administration, which funds the hotline, said in response to the study.

Research results 'very heartening,' expert says

Jill Harkavy-Friedman, who leads the American Foundation for Suicide Prevention's research program and was not involved in the study, said the results were "very heartening and very positive." She wants to see more research replicating the results, but she said the authors did a "great deal of work" to weed out other possible factors for the decline.

The entire mental health system is key to lowering suicide rates, Harkavy-Friedman said. 988's power to navigate that system, helping callers make safety plans, connecting them to local crisis intervention teams and referring people to longer-term care, has led to "extraordinary" impact, she said. And simply having someone to call in a moment of crisis can also be lifesaving.

"That is the strength of the crisis line," Harkavy-Friedman said. "When you call, it de-escalates the crisis so the person has greater capacity to address whatever it is that's driving their emotions at the moment."

Experts say the overall patchwork of federal and state funding for call centers remains insufficient to meet the true level of need.

Health Secretary Robert F. Kennedy Jr.'s federal budget request maintains stable 988 funding at $534.6 million for fiscal year 2027, in anticipation of 11 million contacts next year.

The hotline "is not a panacea for preventing suicide death," but the number of lives it has saved "is a really big deal and underscores the need for sustained investment in 988 from federal, and especially state, lawmakers," said Jonathan Purtle, a New York University mental health policy researcher.

Specialized line for LGBTQ+ youth

In a Capitol Hill hearing Tuesday, Sen. Tammy Baldwin pressed Kennedy to follow through on a "legal requirement" to restore 988's specialized line for LGBTQ+ youth. The administration abruptly cut the program last summer, despite evidence that the population faces disproportionately high suicide rates.

WATCH: Trump administration pulls the plug on suicide hotline for LGBTQ+ youth

"Yes, we are working on getting it up now," Kennedy told the Wisconsin Democrat. Spokespeople for the Substance Abuse and Mental Health Services Administration and the Department of Health and Human Services did not immediately provide The Associated Press with any timeline or details of that restoration.

Patel said the specialized services for high-risk groups — including the LGBTQ+ line — are part of what makes the program work.

"Our findings should be read as evidence that this is a program worth preserving and expanding, not one to scale back," he said.