Barbara Bush released from hospital

HOUSTON A hospital spokesperson says the former first lady was alert, talkative and appeared to be getting stronger when she was released from the hospital this morning.

Mrs. Bush suffers from Graves disease, an autoimmune disorder that affects the thyroid. Experts say a mild relapse, like the one she suffered, is not unusual.

Barbara Bush was first treated for Graves disease back in 1989. It's an immune disorder that kicks a person's thyroid into overdrive.

Doctors say it appears Mrs. Bush had a mild relapse, and a result, they adjusted her medication.

"The age has a lot to do with the complexity of symptoms that you run across," Dr. Richard Robbins says.

Dr. Robbins did not treat Mrs. Bush but specializes in the treatment of Graves disease. He says complications from Graves can be much more serious and pronounced in elderly people, and often times, it can affect their hearts.

"In older people, they can get fast heart rates, arrhythmias and some congestive heart failure as a manifestation of over active thyroid," he says.

Graves disease affects anywhere from 13 to 15 million people in this country, mostly women, and it's a medical condition that often goes undiagnosed.

The 84-year-old former First Lady was admitted to Methodist Hospital on Saturday after she said she hadn't been feeling well. Doctors then ran a battery of tests in an effort to find the source of her concern.

While hospitalization isn't typically required to adjust a patient's medication, Dr. Robbins says a person's age, medical history and complexity of their symptoms definitely come into play.

A hospital spokesperson tells us Mrs. Bush is deeply touched by all of the prayers and good wishes she's received. She is expected to return to her normal activities soon.