Dementia

The forgotten problem

The rising prevalence of dementia is a global emergency

OF ALL THE troubles facing the world, the rising prevalence of dementia might seem among the less pressing. The reason behind it—longer lifespans—is to be cheered; it does not advance at the speed of a viral infection but with the ponderous inevitability of demographic change; and its full effects will not be felt until far into the future. But the reality is very different. Dementia is already a global emergency. Even now, more people live with it than can be looked after humanely. No cure is in the offing. And no society has devised a sustainable way to provide and pay for the care that people with it will need.

“Dementia” is an umbrella term for a range of conditions, with a variety of causes, of which the most common is Alzheimer’s disease, accounting for 60-80% of cases. It usually starts with forgetfulness and a mild loss of cognitive functioning. But as it advances, people lose the ability to look after themselves. Many require round-the-clock care long before they die. It does not just affect the elderly, but they are much more likely to have it—and life expectancy globally has climbed from not much more than 30 a century ago to over 70 now, and over 80 in rich countries. By some estimates, 1.7% of 65- to 69-year-olds have dementia and the risk of developing it doubles every five years after that. At present, about 50m people around the world have the condition, a number expected to rise to 82m by 2030 and 150m by 2050. Most of the new cases are in the developing world, where populations are rising and ageing.

The problems these numbers will bring everywhere have already been felt in countries where people are older, and especially acutely during lockdowns—witness the difficulty of…