HOUSTON -- Former President George H.W. Bush, 90, was taken to Methodist Hospital Tuesday in an ambulance as a precaution, his staff said in a statement.
The president was experiencing shortness of breath.
"President Bush was taken by ambulance to the Houston Methodist Hospital as a precaution after experiencing a shortness of breath earlier this evening," the statement said. "The former president, age 90, will be held for observation, again as a precaution."
Bush is the oldest living former president and vice president. He is also the last living former president who is a veteran of World War II.
Bush spent nearly two months in the same hospital and was discharged in January 2013 after treatment for a bronchitis-related cough and other health issues.
Bush, who can no longer use his legs, most recently appeared seated in a wheelchair at an event in November at Texas A&M University with his son, former president George W. Bush.
In June, the elder Bush celebrated his 90th birthday by making a tandem parachute jump near his summer home in Maine.
White House spokesman Eric Schultz says President Obama and the First Lady "send their good wishes" to Bush and his family.
(The Associated Press contributed to this report.)