SOCIAL EPIDEMIOLOGY OF AGING IN THE UNITED STATES

Unprecedented changes in the structure of the population have led to a "graying" of America. Increase in life expectancy and declining birth rate have resulted in a larger proportion of Americans who are elderly. At the beginning of this century, less than 10% of the population were aged 55 or older—about 7.1 million people; in 1982, more than one-fifth of the population were over the age of 55—an estimated 48.0 million persons. In the year 2050, one in three persons is expected to be over the age of 55. During the past two decades, the 65-plus population grew twice as fast as the rest of the population, and those over 85 years of age comprised the fastest growing segment of the U.S. population. In 1960, those over the age of 85 comprised one-half of 1% of the population; just 20 years later, this proportion was doubled and is expected to double again to 1.9% in the year 2000. Given current projections, the 85-plus age group will comprise more than 5% of the population in the year 2050. There are currently more than 2.2 million people in the U.S. over the age of 85 and this age group is expected to increase to 16 million in 2050 (Figs 1,2).