According to a RAND study, a Pentagon-funded think group, dementia affecting US officials poses a threat to national security. The study was issued this spring, at a time when many senior US officials entrusted with some of the nation's most sensitive intelligence had public breaches, sparking calls for resignations and criticism over Washington's aging leadership.

As a member of the so-called Gang of Eight congressional leadership, Sen. Mitch McConnell, R-Ky., has access to secret material that no other member of Congress has.

Sen. Dianne Feinstein, D-Calif., was a member of the Gang of Eight for years and remains a member of the Senate Intelligence Committee, where she has served since 2001.

Feinstein experienced confusion about voting and has had memory lapses as well, like forgetting an absence she took for a month.

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The study details that US officials with knowledge of highly classified materials who develop dementia could disclose the information, making them a risk to national security.

“Individuals who hold or held a security clearance and handled classified material could become a security threat if they develop dementia and unwittingly share government secrets,” the study notes.

The report explains that longer lives and a late retirement age mean "challenges associated with cognitive impairment in the workplace will need to be addressed,” citing a security blind spot due to the limited research on the topic.

A number of officials who have access to classified government material are subjected to stringent and intrusive vetting processes. When applying for a clearance, they may be subjected to hours-long polygraph exams, character interviews with former instructors, friends, and neighbors, and continued automated surveillance of their bank accounts and other personal information. "You basically give up your Fourth Amendment rights," one senior Pentagon official told The Intercept. 

However, the study authors note that there appears to be no screening for age-related cognitive deterioration. In reality, there is no mention of aging or cognitive deterioration in the director of national intelligence's instruction on continual examination. 

While the report does not identify any US leaders, its publication coincides with a heated discussion over gerontocracy, or rule by the elderly. Google searches for the word "gerontocracy" increased after Mitch McConnell's first freezing incident in July.

When he was questioned about the incident, McConnell explained that Biden had called to check on him and explained he "got sandbagged", referring to Biden's fall in Colorado in June.

Biden also has numerous voters concerned about his well-being, with a CNN report last week finding that 67% of Democrats think the party should nominate another candidate due to his old age.

In August, a Newsweek poll indicated that a majority of Democrats were concerned about Biden's ability to complete his duties due to his old age, with 75% of voters citing concern that he was 80 years old. 

The US leadership is the oldest today than ever, with senior Congress members increasing considerably in recent years. In 1981, only 4% of Congress was over 70, a number that had risen to 23% in 2022.

Vox previously reported that a pharmacist claimed they had filled out Alzheimer's medication for numerous Congress members in 2017.

Feinstein's assistants have worked for years to keep her decline hidden, establishing a system to keep her from traversing the halls of Congress alone and risking unsupervised contact with a reporter.

Despite the public outcry, there is no indication that officials will step down.