Summary: A long-term continuous marriage, from midlife to old age, is associated with a lower risk of developing dementia.
If you’ve been married continuously for many years in your 40s, you have a lower risk of developing dementia in old age, according to a recently published study based on health survey data from the HUNT Study in the Northeast. Trøndelag.
«Being married can influence dementia risk factors,» says Vegard Skirbekk of the Norwegian Institute of Public Health (NIPH/FHI).
The researchers looked at different types of marital status in people over a 24-year period – from ages 44 to 68 – and investigated whether this status was linked to a clinical diagnosis of dementia or mild cognitive impairment (MCI). after the age of 70.
The results show that the group that was continuously married throughout the period had the lowest incidence of dementia.
The highest incidence was seen in divorced and single people.
Children reduce the risk
Asta Håberg is a physician at St. Olav’s Hospital and a professor at NTNU, as well as a researcher at NIPH/FHI. She says the survey results contained surprises.
“The exact cause of dementia is a mystery. This survey indicates that being married and a lower risk of dementia are linked, but we don’t know why,” says Håberg.
“One theory is that married people lead healthier lives and that this explains the differences in risk of various diseases. In this survey, we found no support for differences in health between married and unmarried people explaining the difference in dementia risk.
In the HUNT survey, approximately 150,000 people living in Nord-Trøndelag gave their consent for health information to be made available for research. The researchers used this data to check the incidence of dementia against health factors such as smoking, high blood pressure, obesity, physical inactivity, diabetes, psychological problems and being sick. have close friends.
“We thought these factors meant something, but they didn’t explain anything,” says Håberg.
However, the researchers found that having children mattered and reduced the risk of dementia by 60% among the unmarried people in the study.
“Some people have theorized that if you have children, you stay more cognitively engaged. For example, you have to deal with people and participate in activities that you wouldn’t otherwise have to do. your brain so that maybe it works better. That way you build up a kind of cognitive reserve,» says Håberg.
Still a lot of unused data
This “reserve” in the brain is not structural. It doesn’t show up on an MRI or by opening up the brain and looking inside. This is part of the “mystery of dementia”. But Håberg hopes to uncover some of the mystery through this study.
“We do not know if it is the fact of being married or having children that protects against dementia, or if it is a case of pre-selection, for example. This would mean that people who have a lower likelihood of developing dementia also have a higher likelihood of finding a partner and having children. But the fact that we have the HUNT study means that we have a lot of data available that we have not yet used to further this study,” says Håberg.
As a doctor, she is not convinced that dementia is an inevitable consequence of aging.
“It is common to think that ‘if you live long enough, sooner or later you will develop dementia.’ I’m not sure I agree with that, given this theory that we might have cognitive reserves.
Certain conditions may help build up such reserves, which means you start out with more connections in the brain. For example, we have observed that education is a factor, and the more education you have, the better the “reserves” you accumulate.
And yet, when a highly educated person contracts Alzheimer’s disease, the disease progresses as rapidly as anyone else. The reserves therefore have a retarding effect, but only until the disease strikes.
Make it easier for you to have children
The study results are part of the NIH-funded REFAWOR (Cognitive reserve work and family) research project in the United States, which is part of the «Changing Lives, Changing Brains» program under the auspices of the Institute. Norwegian Public Health.
REFAWOR has a budget of almost three million euros and aims to study how changes in living and working conditions affect the risk of Alzheimer’s disease, dementia and cognitive impairment in older people. These diseases are expected to triple by 2050.
Researchers are now taking a closer look at the importance of having children for dementia risk, the types of jobs people have and how retirement age may affect risk.
Dementia is a collective term for various brain diseases and injuries. Memory weakens and the ability to think logically is affected. Eventually, it becomes difficult to fend for yourself and carry out daily activities. No medical treatment for dementia is currently available.
“We have long dreamed of finding a drug for dementia, but we have not yet succeeded. So we’re looking at the social determinants. What can society do to reduce the risk? The state could make it easier to have children, for example,” says Håberg.
Genes can make us more susceptible
One of the next steps is to look at genetic connections, says Skirbekk.
«We know that certain genes increase the risk of dementia, but people with these genes can still live to be 90 without experiencing cognitive problems,» he says.
“You could say that the increased risk inherent in the genes can be considered a vulnerability, whereas having a stable family life could possibly reduce this vulnerability.
He points out that this study says nothing about the biological mechanisms behind dementia.
“But it shows that being married can influence risk factors. You become more cognitively active, cope better with adversity, and are less prone to stress. The partner represents a security that provides a buffer.
The book is published in the Journal of Aging and Health.
The study does not consider whether there is a difference between being an unmarried couple and a married couple. Less than one percent of unmarried people in the survey cohabited with a partner.
“There are very few roommates in this age group at HUNT,” says Håberg.
About this news about relationships and dementia research
Author: Ingebjørg Hestvik
Contact: Ingebjørg Hestvik – NTNU
Picture: Image is in public domain
Original research: Free access.
«Marital histories and associations with late-onset dementia and risk of mild cognitive impairment in the HUNT4 70+ study in Norway» by Vegard Skirbekk et al. Journal of Aging and Health
Marital histories and associations with late onset dementia and risk of mild cognitive impairment in the HUNT4 70+ study in Norway
Goals: Previous studies suggest that being married later in life protects against dementia and that being single in old age increases the risk of dementia. In this study, we examine marital status trajectories from midlife and their association with dementia and mild cognitive impairment (MCI) at age 70+ using a large Norwegian population sample. .
Methods : Based on a general population sample linked to population registers (NOT = 8706), we used multinomial logistic regression to examine the associations between six types of marital trajectories (single, continuously divorced, intermittently divorced, widowed, continuously married, intermittently married) between ages 44 and 68 years from national registries and clinical dementia or diagnosis of MCI after age 70. We estimated relative risks (RRR) and used mediation analyzes controlling for education, number of children, smoking, hypertension, obesity, physical inactivity, diabetes , mental distress and lack of close friends in their 40s. Inverse probability weighting and multiple imputations were applied. The population attributable fraction was estimated to assess the potential reduction in dementia cases due to marital history.
Results: Overall, 11.6% of participants were diagnosed with dementia and 35.3% with MCI. The prevalence of dementia was lowest among continuously married people (11.2%). After adjusting for confounding factors, the risk of dementia was higher for unmarried (RRR = 1.73; 95% CI: 1.24, 2.40), permanently divorced (RRR = 1.66 95% CI: 1.14, 2.43) and intermittently divorced (RRR = 1.50; 95% CI: 1.09, 2.06) compared to continuously married. In general, marital trajectory was less associated with MCI than with dementia. In the counterfactual scenario, where all participants had the same risk of being diagnosed with dementia as the permanently married group, there would be 6.0% fewer cases of dementia.
Discussion: Our data confirm that staying married in their 40s is associated with a lower risk of dementia and that divorced people account for a substantial share of dementia cases.