IMMUNE PARAMETERS IN A LONGITUDINAL-STUDY OF A VERY OLD POPULATION OFSWEDISH PEOPLE - A COMPARISON BETWEEN SURVIVORS AND NONSURVIVORS

As a part of an ongoing longitudinal investigation, this study examine d relationships between survival and selected immune system parameters in a sample (n = 102) of very old individuals (86-92 years at the tim e of initial immune system data collection). Analyses were performed c omparing initial lime-point measurements from those individuals who we re alive (n = 75) and those who were deceased (n = 27) two years after initial data collection. Immune system measurements consisted of dete rmination of peripheral blood lymphocytes and lymphocyte subsets, as w ell as T-cell responses to activation by Concanavalin A. Cluster analy sis identified a subgroup associated with nonsurvival which indicated characteristics that included: poor T-cell proliferative responses, hi gh CD8 percentages, and low CD4 and CD19 percentages. This multivariat e analysis suggested that combinations of immune system parameters pre dict two-year survival otherwise not apparent when single immune syste m parameters were evaluated in the elderly.