Pope’s retirement a reality check for aging business lions

(Bloomberg) — How old is too old to lead?

The retirement of Pope Benedict XVI, the first such abdication in almost six centuries, may force aging lions from politics, academia and business to confront that painful question. For the legions of leaders well into their 80s and beyond, the evidence isn’t encouraging.

Pope Benedict will step down two months before his 86th birthday because he no longer has the strength to lead the world’s 1.2 billion Catholics, he said this week. His decision may prove emblematic of an older generation that is perhaps healthier than earlier generations, yet may harbor unrealistic expectations about what’s physically possible as the body ages.

“The Pope is probably making a wise decision because his ability to totally manage the church is going to be more limited on average because he’s 85,” says Leo Cooney, 69, chief of geriatrics at Yale School of Medicine.

Many of the world’s most influential business leaders are confronting the same decision as they continue to rule their empires in their 80s and even 90s. Leaders in their 80s include Berkshire Hathaway Inc.’s Warren Buffett, 82; News Corp.’s Rupert Murdoch, 81; BP Capital LLC’s T. Boone Pickens Jr., 84, and Tracinda Corp.’s Kirk Kerkorian, 95. Viacom Inc. Chairman Sumner Redstone and Berkshire Hathaway Inc. Vice Chairman Charles Munger are 89. Li Ka-Shing, chairman of Hutchison Whampoa Ltd., is 84.

“The prevalence of significant cognitive and functional problems does increase dramatically in the mid-80s,” says Cooney. “It’s probably a good idea to reassess one’s ability to be in positions of power at that time.”

By the time people reach their 80s, muscle mass decreases, and so do strength and endurance. Almost 70% of Americans between the ages of 85 and 89 have a disability, defined as a substantial limitation in major life activity, according to a 2011 report on aging by the Census Bureau and National Institute of Aging.

“There’s definitely not a magic number, but there are things that happen more as you age,” says Audrey Chun, 41, medical director of Martha Stewart Center for Living at Mount Sinai Medical Center in New York. “As you start collecting these conditions where you have more than one chronic condition, those things can start taking a higher toll.”

As conditions accumulate, so do the medications, which can lead to side effects that can leave people somewhat impaired, Chun said. Dementia and cognitive decline also kick in. By age 90 about half of people have some sort of cognitive problem, she said.

Difficulty performing errands alone and mobility-related activities such as walking and climbing stairs are the most common types of disability, affecting two-thirds of people ages 90 and older, according to the Census Bureau and National Institute of Aging study. Hearing and vision loss affect 43% and 26%, respectively.