Covid may have affected the brain health of many over-50s, whether or not they caught the disease, a new study shows. It says the pandemic “resulted in a significant worsening of cognition in older adults”. Known dementia risk factors such as loneliness and lack of exercise may have been partly to blame. As the pandemic disrupted our lives, more than 3000 volunteers in the UK completed annual questionnaires and took online cognitive tests designed to measure changes in functions including memory. The resulting PROTECT study, published in The Lancet Health Longevity journal says pressure on the NHS may have deprived some people of opportunities for the early detection of mental decline. And its authors call for long term checks on people with a history of Covid infection – “particularly those cognitive impairment, for whom conversion to dementia within 5 years is a substantial risk”.