Being cynical not only increases the risk of heart disease and attacks, but also heightens the chances of developing dementia, according to a study conducted at the University of Eastern Finland Kuopio.

According to Merriam-Webster, cynicism is defined as the belief that others are generally selfish and dishonest. Psychologists believe that it is a type of a chronic anger that develops over time, CNN reports.

Previous studies have already established the link between cynicism and heart disease, early death and poor health. This is the first study to determine the relationship between the trait and dementia.

"These results add to the evidence that people's view on life and personality may have an impact on their health," said study author Anna-Maija Tolppanen, PhD, in a statement. "Understanding how a personality trait like cynicism increases the risk for dementia might provide us with important insights on how to reduce risks for dementia."

Tolppanen said that past studies showed people, who are open and optimistic, have a lower risk of dementia.

For the study, about 1,449 people around 71 years old undertook tests for dementia and a questionnaire to calculate their level of cynicism. In the questionnaire, participants were asked whether they agree with statements like "I think most people would lie to get ahead," "It is safer to trust nobody" and "Most people will use somewhat unfair reasons to gain profit or an advantage rather than lose it."

Based on the scores, participants were divided into low, moderate and high levels of cynical distrust.

The researchers found that people, who display high levels of cynical distrust, were three times more likely to develop dementia, than their least cynical counterparts.

"There are likely to be many risk factors for dementia and this study suggests that a person's outlook may also have a role to play. However, it can be hard to separate whether cynical distrust could contribute to dementia, or is actually a symptom of disease. Nevertheless, any addition to our understanding of what might affect disease development is important," said Dr Simon Ridley from Alzheimer's Research UK, Daily Mail UK reports.

The findings are published in Neurology, the medical journal of the American Academy of Neurology.