[A meta-analysis combines data from different trials performed by different groups to increase the ability to detect important patterns in the outcomes]. Researchers combined results from 12 trials including a total of 96,158 individuals, with a mean age of 69 years, who were followed for an average of just over 4 years. Those taking an antihypertensive had a slightly smaller risk of developing dementia than those not taking one (7% vs 7.5%) Cognitive impairment showed a similar modest effect (20.2% vs 21.1%). Although these differences are numerically small, researchers believe that the effect is real because it is based on such a large number of individuals. However, lowering blood pressure did not improve or worsen an individual’s scores on cognitive tests.