Cumulative index of health deficiencies as a characteristic of long life.
OBJECTIVE
To describe the accumulation of aging-associated health disorders using a cumulative measure known as a frailty index (FI) and to evaluate its ability to differentiate long- and short-life phenotypes as well as the FI's connection to aging-associated processes in older people.


METHODS
Retrospective cross-sectional and longitudinal studies.


METHODS
The National Long-Term Care Survey (NLTCS) data that assessed health and functioning of U.S. older individuals (> or =65) in 1982, 1984, 1989, 1994, and 1999 were analyzed. The NLTCS sample in each survey represents a mixture of longitudinal and cross-sectional components.


METHODS
Approximately 5,000 individuals in each survey.


METHODS
A cumulative index of health and well-being deficiencies (disabilities, signs, diseases) was calculated as a count of deficits observed in an individual divided by the total number of all considered deficits.


RESULTS
Men and women who died before the age of 75 and those who died after the age of 85 exhibited remarkably similar FI frequency patterns despite the 10-year age difference between age profiles in these samples. Long life is consistently characterized in longitudinal analyses by lower FIs. FI dynamics are found to be strongly sex sensitive.


CONCLUSIONS
The FI appears to be a sensitive age-independent indicator of sex-specific physiological decline in aging individuals and a sex-specific discriminator of survival chances. The FI is a promising characteristic suitable for improving sex-sensitive forecasts of risks of adverse health outcomes in older people.
Kulminski
Alexander M
AM
Center for Population Health and Aging, Duke University Population Research Institute, and Department of Sociology, Duke University, Durham, NC 27708, USA. alexander.kulminski@duke.edu
Ukraintseva
Svetlana V
SV
Akushevich
Igor V
IV
Arbeev
Konstantin G
KG
Yashin
Anatoli I
AI
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D016330:Frail Elderly; D006305:Health Status Indicators; D006306:Health Surveys; D006801:Humans; D008136:Longevity; D008137:Longitudinal Studies; D008297:Male; D012189:Retrospective Studies; D012737:Sex Factors; D014481:United States