Demographic, health, cognitive, and sensory variables as predictors of mortality in very old adults

Cognitive and sensorimotor predictors of mortality were examined in the Aus tralian Longitudinal Study of Ageing, controlling for demographic and healt h variables. A stratified random sample of 1,947 males and females aged 70 and older were interviewed, and 1,500 were assessed on measures of health, memory, verbal ability, processing speed, vision, hearing, and grip strengt h in 1992 and 1994. Analyses of incident rate ratios for mortality over 4- and 6-year periods were conducted using Cox hierarchical regression analyse s. Results showed that poor performance on nearly all cognitive variables w as associated with mortality, but many of these effects were explained by m easures of self-rated health and disease. Significant decline in hearing an d cognitive performance also predicted mortality as did incomplete data at Wave 1. Results suggest that poor cognitive performance and cognitive decli ne in very old adults reflect both biological aging and disease processes.