Republicans have questioned Biden's cognitive abilities since before he was elected in 2020. Biden's doctor said, after November’s physical, that he was healthy, vigorous and fit for office. Republican senator Roger Marshall, also a physician, expressed interest in having the president take an annual cognitive test, much like he has an annual physical examination - citing concern for his health. Marshall said he feels there has been a ‘deterioration’ in Biden's ‘mental capacity’ over the past year: ‘I think we're all very concerned about his health, and it is a national security issue.’ On 15 February, 38 Republicans sent a letter to the president requesting he take a cognitive test. The White House did not immediately respond to a request for comment on Marshall's comments or the letter. Biden is 79, the oldest person ever to be elected president.