Pope Benedict XVI. (Getty Images)
Janice Lloyd, USA TODAY
Health experts on aging admired Pope Benedict XVI 's decision to resign Monday, citing visible clues about his declining health and respecting his honesty about an inability to fulfill responsibilities as he grows older.
The pope, 85, noted Monday in his speech to the cardinals he is slowing down: "Both strength of mind and body are necessary - strengths which in the last few months, have deteriorated in me.'' The Vatican stressed that no specific medical condition prompted Benedict's decision, but in recent years, the pope has slowed down significantly, cutting back his foreign travel and limiting his audiences.
Walking is a "powerful indicator of vigor and frailty,'' says Stephanie Studenski, director of research in the division of geriatric medicine at the University of Pittsburgh.
"My sense is that he is having a lot of difficulty walking," she says. "The many organ systems that you need to walk well shows he is declining. The brain, the spinal cord, the nerves, the heart, muscles and bones are all needed to walk well."
Her research findings have recommended clinicians assess well-being among older adults by examining walking speed: Faster walking is associated with longer survival among older adults and has been shown to reflect health and functional status.
The pope now goes to and from the altar in St. Peter's Basilica on a moving platform, to spare him the long walk down the aisle. Occasionally he uses a cane.
His 89-year-old brother, Georg Ratzinger, according to the Associated Press said: "His age is weighing on him. At this age, my brother wants to rest more."
But no one should jump to the assumption everyone in his 80s wants to rest more or should step down from responsibilities.
"I've seen plenty of men, who in their 80s and 90s, if they're fit they go on and on, and are practically immortal until they start to have a problem,'' says Thomas Perls, professor of medicine at Boston Medical Center.
Perls says geriatricians would have examined the pope to see "if there is any reversible process for the problems. If he is experiencing such frailty and heart difficulties that can't be reversed, it doesn't bode well for his future.''
The pope had been recently advised to discontinue trans-Atlantic flights.
"Even for healthy normal people sitting around during a flight for a long period of time can put you at an increased risk for thrombosis of the legs,'' Perls says.
Deep venous thrombosis occurs when a blood clot embeds in the deep veins of the lower legs, thighs, or pelvis. A clot blocks blood circulation through these veins, which carries blood from the lower body back to the heart. Severe complications can occur if a clot breaks loose and lodges in the lungs, causing breathing difficulties or death.
People with advancing dementia are also discouraged from traveling because it can lead to anxiety and confusion.
Recognizing frailty as we age is a big step to take, Studenski says.
"We'd all like to remain vigorous, but the fact is many people confront health problems in late life,'' she says. "I think it is respectful and brave to be honest about oneself and what one can do. It is a gift to others to be able to do that. "
Benedict said he would serve the church for the remainder of his days "through a life dedicated to prayer" and said he is resigning "for the life of the church."
Moving into a new role sets up a model of grace for others to follow, says Toni Miles, director of the institute of gerontology at the University of Georgia in Athens.
"We're all living a lot longer,'' Miles says. "My first thought about the pope was I really admire what he's doing. He's saying I can't handle my job anymore. He is saying he wants someone else to help solve today's problems. That is something more of us need to learn to do."
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