A new Danish study reports some encouraging news for aging populations worldwide. The study, which was recently published in Lancet, compared two groups of nonagenarians born at different decades and aimed to compare the levels of their cognitive function. In total 4,000 people in their 90s identified by the Danish Civil Register System were studied - one group was born in 1905 was assessed at age 93 (in 1998) while the other group was born a decade later in 1915 and was studied in 2010 when they reached age 95. The research group did not exclude any participants, and included both those living in the community and the ones in assisted living or in institutional care who were receiving medical treatments.
Results showed that, despite the two years difference in the study participants, the later-born group was nearly twice as likely to attain a high cognitive score than those born earlier. This group was also longer lived than the other one. Conclusions provide hope that more elderly people are able not to just live longer but also do it in better shape, according to the lead author Kaare Christensen of the Danish Aging Research Center at the country's Institute of Public Health.
This cohort of nonagenarians may also be benefiting from an overall rise in IQ among younger groups over time. As an example, in the US scores have improved roughly by 3 points per decade since 1930, meaning that an average person tested early in the 20th century would have what would be considered an intellectually disabled IQ today. This improvement is called the "Flynn effect" and is due to a variety of factors such as including better dietary habits and overall health as well as to more schooling.
The study leader clarifies, of course, that cognitive function loss or dementia are still big problems for today's societies as more and more people are reaching older ages. Results, however, highlight the importance of exercise, social interaction and continued mental stimulation in helping people living better for longer.
Category: Funding longer lives: Health/medicine