ABSTRACT
The world’s population is aging and expanding at an exponential rate. The human race entered the 19th century with a billion people, the 20th century with 1.6 billion, and today it exceeds 6 billion. The largest increase is predicted to occur in the aging population, those individuals over the age of 65 years. In 1950, less than 5% of the population was older than 65 years; by 2000, more than 400 million (7%) were over 65 years. This percentage is predicted to increase to 15% by 2050, swelling to over 1.5 million elderly. Life expectancy in the developed world over the same time period has increased from 47 years in 1900 to 80 by 2010.1,2 This is attributed in part to developments in modern medicine and improved sanitation that occurred in the 20th century.
