Researchers in the UK say that people who live to be 100 or more are less likely to die of the chronic conditions that are the leading causes of death, such as heart disease can cancer, but more likely to die of sudden declines in their health caused by infections or frailty.

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After reviewing death certificates of 35,867 centenarians who died between 2001 and 2010 in England, the scientists found that around a third died in assisted care homes. The most common cause of death was frailty or old age (28%), followed by pneumonia (18%). Only 8.6% of those over 100 years died of heart disease, and only 4.4% died of cancer, which remain the leading killers in industrialized nations. By comparison, among those between ages 80 to 85, 19% died of heart disease and 24% died of cancer.

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Understanding that most of the oldest old, among the fastest growing proportions of western populations, are more vulnerable to sudden events such as infections that can land them in the hospital and on a downward health spiral, should help countries to better prepare for the ever-growing proportion of longer-lived individuals, say the authors. Globally, centenarians are expected to grow from 317,000 to more than 3.2 million by 2050.

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