Personality traits such as jealousy, anxiety and moodiness could lead to a greater risk of women developing Alzheimer's disease in later life, new research has suggested.
Alzheimer's disease is the most common form of dementia in the UK. It occurs from the gradual death of brain cells, which leads to a loss of mental ability. According to the NHS, 500,000 people in England are affected by Alzheimer's, with women more likely to be diagnosed than men.
Past research on Alzheimer's disease has surrounded the influence of factors such as genetics and heart problems. But researchers at the University of Gothenburg in Sweden set out to investigate whether there is a relationship between certain personality traits and the onset of Alzheimer's.
In a study of 800 women with an average age of 46, the participants were asked to complete personality tests that assessed their levels of neuroticism, extraversion and introversion. These are characterised by factors such as jealousy, anxiety, shyness and assertiveness.
They were also asked to disclose any instances of stress; this was measured on a scale of zero to five, with zero meaning no stressful experiences and five representing continued stress over the past five years. A score between three and five placed the women into the distressed category.
During the 38 years of follow-up, it was found that 19 per cent of the women in the study developed Alzheimer's disease. Those with the highest scores on the neuroticism personality test - characterised by anxiety, jealousy and moodiness - were twice as likely to be diagnosed with the condition as the women with lower scores. This was reinforced among participants who were classed as distressed.
It was also found that women who scored highly on the personality tests that assessed neuroticism and introversion - characterised by shyness and preference for being alone - had the highest risk of developing Alzheimer's.
Lena Johannsson, lead researcher at the university, said: 'Personality may influence the individual's risk for dementia through its effect on behaviour, lifestyle or reactions to stress.'
The study has been published in the journal Neurology. View the abstract here