Getting married may keep dementia at bay

Getting married can lower the risk of developing dementia in later life, according to a study which found that lifelong singletons and widowers are at heightened risk of developing the neurodegenerative disease.
The findings, published in the Journal of Neurology Neurosurgery & Psychiatry, are based on data from 15 relevant studies published up to the end of 2016.
Researchers including those from the University College London in the UK looked at the potential role of marital status on dementia risk, and involved more than 800,000 participants from Europe, North and South America, and Asia.
Married people accounted for between 28 and 80 per cent of people in the included studies; the widowed made up between around 8 and 48 per cent; the divorced between 0 and 16 per cent; and lifelong singletons between 0 and 32.5 per cent.

Pooled analysis of the data showed that compared with those who were married, lifelong singletons were 42 per cent more likely to develop dementia, after taking account of age and sex.
Part of this risk might be explained by poorer physical health among lifelong single people, suggest the researchers.

However, the most recent studies, which included people born after 1927, indicated a risk of 24 per cent, which suggests that this may have lessened over time, although it is not clear why, say the researchers.
The widowed were 20 per cent more likely to develop dementia than married people, although the strength of this association was somewhat weakened when educational attainment was factored in.

However, bereavement is likely to boost stress levels, which have been associated with impaired nerve signalling and cognitive abilities, the researchers note.
No such associations were found for those who had divorced their partners, although this may partly be down to the smaller numbers of people of this status included in the studies, researchers said.
However, the lower risk among married people persisted even after further more detailed analysis, which, the researchers suggest, reflects "the robustness of the findings."
Marriage may help both partners to have healthier lifestyles, including exercising more, eating a healthy diet, and smoking and drinking less, all of which have been associated with lower risk of dementia, researchers said.

Couples may also have more opportunities for social engagement than single people - a factor that has been linked to better health and lower dementia risk, they said.