Related: At a glance

In its 2010 World Alzheimer Report, Alzheimer's Disease International predicted a near doubling in worldwide societal costs because of dementia from $604 billion in 2010, to $ 1,117 billion by 2030.

In its 2013 report, ADI says 80 percent of total worldwide costs are incurred in high-income countries, reflecting the dominance of informal care in less developed countries, and the much lower wages.

China is estimated to have 9.19 million people with dementia. One fourth of the world's dementia population is in China, according to ADI.

In most places in China, health insurance has covered major medication for dementia patients.

But unlike in developed countries, paid care is not available for most dementia patients in China.