Low-income communities with high levels of income inequality were nearly three times as likely to have no access to a psychiatrist, noted the researchers, led by Marigee Bacolod of the Department of Defense Management at the Naval Postgraduate School in Monterey, California.

The military health system includes a network of Defense Department medical centers, hospitals and clinics, and Tricare, the program that manages civilian care covered by the DoD. It covers roughly 9.6 million military personnel, retirees and dependents.

These beneficiaries rely on various health care systems, including the military health system, the Department of Veterans Affairs, Tricare and the private sector for mental health treatment. With fewer than 500 military treatment facilities offering psychiatric services, and the population widely dispersed across the country, the lack of access is "perhaps not surprising," Bacolod wrote.

Service members and their families may require mental health services and treatment at higher levels than civilians as the result of family separations, deployments, frequent moves and combat exposure.

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Military retirees are especially vulnerable to mental health problems and are more likely to reside in rural areas, placing them especially at risk of lacking access to care, the researchers noted.

While the suicide rates of service members and veterans have declined slightly since 2020, they rose significantly among both groups from 2001 to 2020 in concert with the ongoing wars in Afghanistan and Iraq.

The researchers noted that the study had limitations. The study examined only proximity to psychiatrists and not other mental health providers such as psychologists and licensed clinical social workers; it estimated the number of civilian psychiatrists who won't take Tricare because of low reimbursement rates; and it didn't account for physician transitions in and out of a region.

The study used the Health Resources and Services Administration definition of shortage as one psychiatrist for every 20,000 people.

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According to the research, only 13% of Tricare beneficiaries lived in a region with adequate coverage. Those living in Alaska and Hawaii had the worst access within 30 minutes of their homes.

The results suggest that the Defense Health Agency and the VA should reconsider how they are providing mental health access as they reform their systems, the authors noted.

The researchers said that as the DoD considers realigning its health care system, it should develop strategies to cover areas that lack both military and civilian providers, to include raising the number of psychiatrists in vulnerable areas, increasing the use of telemedicine and raising Tricare reimbursement rates.

The VA, which also provides care for eligible retirees, should consider addressing policies that restrict VA health care eligibility to 60% of veterans, the authors wrote. It should also encourage more veterans to use VA health benefits, as just 50% of eligible veterans take advantage of them.

Addressing the shortage of psychiatrists available to the military community could ultimately affect the overall national shortage of psychiatric care, the researchers argued.

"Improving the psychiatrist capacity provided by the military health system could reduce shortage problems experienced by civilians, if initiatives free up the resources of civilian psychiatrists," they wrote.