Medical and social predictors of longevity in the elderly: total predictive value and interdependence.
In the Dutch Longitudinal Study among the Elderly, a probability sample of 3149 persons from the population of the Netherlands, initial ages 65-99 years, was followed from 1955 for 28 years. Vital status was determined in 1983 for 84% of the original sample. Multivariate regression models were used to predict the realized probability of dying (RPD), a measure of longevity based on actual survival time, sex and age at baseline. Predictor variables included physical, mental and social indicators of health status. The total variance explained was 20.2%. Objective health (rated by the examining physician) showed the strongest relationship with the RPD. Upon removing objective health from the model, 19.5% of the variance remained explained. Separate analyses were performed for (1) bio-medical, physical and mental examination variables, (2) disability and health care use variables, and (3) social and psychological variables; in each case the variance explained was over 11%, demonstrating considerable interdependence among predictors. Across different regression models, bio-medical and disability variables proved to be the most stable predictors of longevity.
Deeg
D J
DJ
Department of Public Health and Social Medicine, Faculty of Medicine, Erasmus University Rotterdam, The Netherlands.
van Zonneveld
R J
RJ
van der Maas
P J
PJ
Habbema
J D
JD
D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D015438:Health Behavior; D006304:Health Status; D006801:Humans; D008136:Longevity; D008297:Male; D015233:Models, Statistical; D009426:Netherlands; D012044:Regression Analysis; D012944:Social Support; D012959:Socioeconomic Factors