One of the most distressing things for a family is when a patient, usually elderly, suddenly gets worse and seems to be heading for a cliff.

When I was a medical student at Columbia, we admitted a ninety-seven-year-old history professor with a broken hip. At his age, he was active and spry and had all his marbles. He was still writing and teaching. He walked to work every day from his apartment up Riverside Drive to Columbia, and one winter day he fell on the ice and broke his hip. When we admitted him, he was absolutely fine, except for his hip. He had uneventful surgery to fix it, but then a minor complication set in, and then another, and another, each worse than the last. Ten days later he was dead.

For the elderly, a seemingly minor incident can be like an avalanche. It starts with a pebble coming loose. That one hits others and they start to slide down the hill, and they hit more, and soon the whole mountainside is coming down. That’s what can happen with old people. They seem fine from the outside, but they’re old on the inside, and a minor event can trigger an avalanche.