People who look on the bright side of life may be less likely to develop dementia, research suggests. A study of more than 9,000 people found those who scored higher for optimism were 15% less likely to receive a diagnosis over 14 years. American dictionary Merriam-Webster defines optimism as “a doctrine that this world is the best possible world”, or “an inclination to put the most favourable construction upon actions and events or to anticipate the best possible outcome”.
Writing in the journal of the American Geriatrics Society, researchers said: “Previous studies suggest that higher optimism is associated with better cognitive function and slower cognitive decline in aging. These findings suggest a potential value of optimism in supporting healthy aging, which could be considered in future research on dementia prevention initiatives.”
The study included 9,071 cognitively healthy US adults with an average age of 74. Some 3,027 went on to develop dementia during the study period.
Their level of optimism was scored using the Life Orientation Test Revised, a survey that asks to what extent respondents agree with statements such as: “In uncertain times, I usually expect the best.”
The test was generated a core between six and 36, with high scores indicating greater optimism.
After adjusting for factors such as age, sex, race and ethnicity, education and chronic health conditions, a six-point increase in optimism on the scale was associated with a 15% lower risk of developing dementia.
The study was observational so could not prove that optimism caused the difference in dementia risk.
However, the researchers noted that there were possible biological processes. Previous research has suggested that people who are more optimistic tend to have healthier immune responses and higher levels of plasma antioxidants.
Optimists may have stronger social networks and lower stress levels, which have been linked to healthy ageing. They may also be more likely to exercise and less likely to smoke.
The researchers added: “Together with previous studies, our findings provide support for the possibility that optimism causally contributes to cognitive health and may be considered an asset for brain health.
“While optimism has been estimated to be about 25% heritable, numerous studies show it can be modified with interventions specifically designed to alter levels of optimism.
“Therefore, studies on optimism and dementia could provide important evidence for future dementia prevention initiatives.”
