Dr. Marc Siegel, Fox News Contributor and Professor Of Medicine at NYU Langone Medical Center, gave his diagnosis for prominent lawmakers who have shown signs of cognitive or physical health issues while serving in office, sounding the alarm on the need for "more transparency" for the American people.

"I believe the voters of the states involved have a right to know whether their senator is fit for the job and able to serve," Siegel said. "While technology can help [Sen. John] Fetterman and teleprompters can help Biden this isn't enough. Are they up to the job? We need more transparency and info. The lives of others are on the line based on the important decisions they have to make."

"The majority of the American public (even Democrats) feel he is too old to run, but the issue isn't age, it's the question of fitness," Seigel said of Biden, who often raises eyebrows over misspoken words (he has dealt with a stutter since he was a child) and times when he appears confused.

The president underwent his annual physical exam Thursday that cleared him as fit to serve, but the report failed to mention any results from neurological tests. 

BIDEN HEALTH EVALUATION MISSING MENTAL STATUS EXAM: MEDICAL EXPERT

"Biden, the issue is that his stiff legged gait and frequent cognitive errors could be a tip off to a brain problem such as dementia or normal pressure hydrocephalus, but the workup would be an MRI or brain imaging study and neuropsych testing including a cognitive exam such as the Montreal cognitive test. The mini-mental status exam that was mentioned is very limited and wouldn't add much," Siegel told Fox News Digital. 

DOCTORS REACT AFTER FETTERMAN CHECKS INTO HOSPITAL FOR CLINICAL DEPRESSION

"It is very noteworthy that [Biden's physician Dr. Kevin] O'Connor ascribed the stiff gait to arthritis of the spine and peripheral neuropathy and mentioned physical examination to rule out serious neurological disorders such as MS and stroke, but made no mention of MRI of the brain or neurocognitive tests. These are significant omissions in the report esp given the frequency and severity of his so-called gaffs," Siegel added.

Fetterman was admitted into a Washington, D.C. hospital twice in a week, checking himself in on Thursday to be treated for "clinical depression."

"We should feel compassion and as a physician I am glad he is coming forward and can be a role model for others, but at the same time clinical depression requiring hospitalization is severe and according to a Cochrane review especially difficult to treat after stroke requiring combinations of medicine and therapy," Siegel said of Fetterman, who suffered a stroke in May 2022 while on the campaign trail.

Siegel also speculated that the depression could be a side effect of last year's stroke. "According to a 2016 study in STROKE 1/3 people after stroke are reported to have depression, but the number is likely far greater," he said.

Sen. Dianne Feinstein, D-Calif., who announced that she will not be seeking re-election in 2024, did not realize she resigned when asked by a reporter about the announcement on Tuesday.

"Feinstein too appears to be well past the point where she can function effectively," Siegel wrote.

The Democrat, who is 89 years old, also reportedly left the Senate floor not knowing if she voted for anything.

Sen. Bob Casey, D-Pa., also recently had a "successful" prostate cancer surgery, and Siegel believes he will be in good enough health to serve after his recovery.

"Casey is undergoing surgery for prostate cancer which will likely cure him, and he will be able to resume work shortly in a matter of days or weeks," he stated.