New research shows that longevity and disability do not necessarily come hand in hand. The study, which began in 1998, tracked 2,234 Danish people born in 1905 for a total of seven years. The majority had died by the end of the study – 156 of the original 2,234 participants reached their 100th birthday; however those that were still alive were assessed when they reached 94, 96, 98, and 100. Results showed that the percentage of participants living independently decreased only slightly – from 38.9% to 32.7% – over the course of the study.
In contrast to this, results also showed that the incidence of disability increased dramatically over the course of the study – from 30.1% at 92 to 67.3% at 100. However, the authors explain that the reason for this apparent paradox is due to the high level of mortality among independent participants and that the few that survived the longest were least likely to be dependent at the start of the study.
Lead author of the study, Dr Karre Christensen, said of the findings: “Some worry that extreme old age leads to extreme levels of disability, but our study shows that people are no more dependent at 100 than at 92.”
Christensen K, McGue M, Petersen I, Jeune B, Vaupel JW. Exceptional longevity does not result in excessive levels of disability. Proc Natl Acad Sci U S A. 2008 Aug 18. [Epub ahead of print]
