Can maintaining cognitive function at 65 years old predict successful ageing 6 years later? The PROOF study

Methods: nine hundred and seventy-six questionnaires were sent by mail to a sample of healthy and voluntary French pensioners. Successful ageing was defined through health status and well-being. Cognitive abilities had been assessed 6 years earlier according to an objective method (Free and Cued Selective Recall Reminding Test (FCSRT), the Benton visual retention test and the similarities subtest of the Wechsler Adult Intelligence Scale-Revised) and a subjective one (Goldberg's anxiety scale, Mac Nair's scale and a Visual Analogue Scale to evaluate memory abilities change in the last 5 years). Results: six hundred and eighty-six questionnaires could be analysed. The mean age was 72.9 +/- 1.2 years old with 59% of women and 99% lived at home. Well-being was negatively correlated with the FCSRT (r = -0.08, P = 0.0318) but positively related with the Benton (r = 0.09, P = 0.0125) and the similarities tests (r = 0.09, P = 0.0118). There is a negative correlation between anxious and cognitive complaints measured at baseline, and successful ageing indicators 6 years later. Conclusion: preservation of cognitive abilities at the age of retirement can predict a successful ageing 6 years later. ClinicalTrials.gov Identifier: NCT00759304.