Was President Taft cognitively impaired?

President William Howard Taft had severe sleep apnea during his presidency from 1909 to 1913, which could explain his tendency to nod off at work or even while playing cards, medical and historical reports indicate.

The condition obstructs air intake, interrupting sleep so often that a person “gets no refreshing sleep” and is chronically drowsy during the daytime, says John G.