The number of deaths by suicide among military service members increased alarmingly in the fourth quarter of 2020, according to the Defense Department's latest quarterly report.

The military recorded 156 deaths by suicide among all services, including active-duty, National Guard and Reserve troops, from Oct. 1 to Dec. 31 last year. That is a 25% increase from the 125 such deaths that occurred in the last quarter of calendar year 2019.

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The bulk of the increase came among Guard troops, who saw such deaths increase from 14 in the fourth quarter of 2019 to 39 in 2020. Deaths by suicide among reservists increased by seven, from 11 to 18, over the year. Suicide deaths among active-duty troops actually dropped slightly, from 100 to 99.

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The Pentagon cautioned that these numbers are preliminary and could change as additional deaths are concluded to have been the result of suicide.

In the report, the Defense Suicide Prevention Office cautioned that interpreting trends over time requires statistical analysis.

Though the report did not come to any conclusions about what may have caused the increase in deaths by suicide, it noted "the potential impact of the COVID-19 pandemic on the well-being of our service members and their families."

Some top military leaders have spoken in recent months about the strain their troops have suffered during the pandemic.

"COVID adds stress," Air Force Chief of Staff Gen. Charles "CQ" Brown said during the Air Force Association's virtual Air, Space & Cyber conference last September. "From a suicide perspective, we are on a path to be as bad as last year. And that's not just an Air Force problem, this is a national problem because COVID adds some additional stressors -- a fear of the unknown for certain folks."

A comparison of quarterly reports shows the number of suicide deaths increased noticeably as the pandemic ground on during 2020.

In the first quarter of 2020, deaths by suicide slightly decreased from the same period the previous year -- from 137 in the first three months of 2019 to 133. But the nation began to lock down around mid-March last year, as the scope of the pandemic became apparent.

From April to June 2020, the military recorded 128 deaths by suicide, up from 115 during that period in 2019. That represented an 11.3% increase.

And in the third quarter of last year, 154 service members lost their lives to suicide, up about 22% from 126 the previous year.

That means that if the preliminary numbers remain unchanged, the number of suicide deaths in all components of the military will have grown from 503 in 2019 to 571 in 2020, which would be a 13.5% increase.

While the year-long numbers for the Guard and Reserve increased from 155 in 2019 to 194 in 2020, that is still lower than the 217 deaths by suicide recorded in 2018.

The data includes all known deaths that were confirmed to be suicide, as well as suspected suicide deaths, the report said.

The Pentagon's official statistics for the year will be released in its annual suicide report, which typically comes out around the beginning of October.

-- Stephen Losey can be reached at stephen.losey@military.com. Follow him on Twitter @StephenLosey.

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