Dementia and cognitive impairment are the leading chronic disease contributor to disability and dependence among older people.
Source : https://www.who.int/mental_health/neurology/dementia/dementia_thematicbrief_epidemiology.pdf
Even in developed countries, the workforce of specialists in psychiatry and neurology will be inadequate given aging and increase of world population.
Sources : https://www.thelancet.com/journals/laneur/article/PIIS1474-4422(18)30143-1/fulltext – https://www.staffcare.com/uploadedFiles/psychiatry-shortage-mental-health-white-paper.pdf