Article continues below advertisementDonald Trump's wonky address to the nation has sparked widespread worries about the president's health.On Wednesday night, December 17, the U.S. commander-in-chief, 79, rambled for 18 minutes - jumping from topics like bashing former President Joe Biden and bragging about the Trump administration.Following his speech, cardiac expert Dr. Jonathan Reiner admitted he's "seriously concerned" about Trump's health and said his address sounded "manic."Article continues below advertisementSource: MEGACardiologist Dr.