Researchers from the Peninsula Medical School (in S.W. England), Cambridge University and the University of Michigan compared cognitive performance in older adults from the U.S. and England - and found that those from the U.S. were significantly sharper. The study compared 8,299 Americans with 5,276 English people with both groups taking the same test in the same year. The difference between the two countries was greatest among those over 85 but overall there was a 10-year difference between the two groups with an American 75-year-old performing as well as an English 65-year-old. The average score (out of 24) for English adults over 85 was 8.3 compared to 10.1 for the U.S. participants. For the younger section of the sample (65-74) the average English score was 12.5 compared to 13.8 for the U.S. participants. The study also measured other aspects of the participants' health. The American participants were less likely to be depressed than the English ones and it is known that depression is linked to lower cognitive function. They were also less likely to drink (50% vs 15.5% teetotal) and although they were more likely to have high blood pressure they were also more likely to be being treated for it; untreated high blood pressure can affect cognition. And the American adults tended to retire later which may have kept them sharper for longer.
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