Wait, marriage doesn’t help prevent dementia?
You may have heard that it did.
I connected with Dr. Selin Karakose over email for a Q&A on her new research showing that marriage is not protective against dementia. A postdoctoral researcher at Florida State University, she studies how relationships and mental health shape aging. Her work digs into what truly protects us as we grow older and what does not.
This interview, along with others, originally appeared in my Newsletter Here.
Your study challenges previous research & the long-held belief that marriage offers protective benefits against dementia. So I’m curious, what led you to explore the relationship between marital status and dementia risk?
Our research team investigates the role of various psychosocial protective and risk factors in cognitive health, including dementia risk. Given the evolving role of marriage in society and the increasing number of unmarried individuals (divorced, widowed, or never married), understanding their potential vulnerability to dementia is critical for identifying high-risk groups and providing targeted monitoring and support. Therefore, we aimed to extend prior work by examining whether unmarried individuals have an elevated risk of dementia, using a large sample (NACC) of over 20,000 older adults followed for up to 18 years with annual evaluations at specialized dementia clinics across the United States.
The findings indicate that never-married and divorced individuals had a lower risk of developing dementia compared to married individuals. Were you surprised to see that? Could you elaborate on the potential factors or mechanisms that might explain this trend?
Yes, we were surprised. Accounting for age and sex, we found that widowed, divorced, and never-married individuals had about 50%* or lower dementia risk relative to their married counterparts. Notably, this effect was similar across male and female participants and younger and older adults.
*When hazard ratio [HR] is below 1, the percentage of reduction is calculated as (1/HR)x100. So, for widowed: 1/0.73=37%, divorced: 1/0.66=52%, and never married: 1/0.60=66%).
Despite the commonly held belief that marriage is protective for health, recent research has not found disadvantages of being unmarried compared to married, including in cognitive outcomes. For example, a recent study by Hanes and Clouston (2024) indicated that participants experienced slower rates of cognitive decline following divorce, which could potentially lead to a lower risk of dementia over time.
Several factors could potentially contribute to these results. There is some evidence that divorce can lead to greater happiness and life satisfaction, and widowed individuals may experience an increase in close network size in the years following widowhood, which could potentially protect against dementia risk. Older married individuals, on the other hand, may have a smaller social network, tend to be less self-reliant, and may experience stressful conditions such as caregiving, which could contribute to the lower risk of dementia. Another important possible explanation is that the findings could suggest a delayed diagnosis among unmarried individuals. More research is needed to identify the mechanisms linking marital status and incident dementia.
Since people who aren’t married might get diagnosed with dementia later than those who are, how did you handle that in your study? And how might it affect the conclusions we draw from the results?
We examined the average age of dementia onset and the severity at onset: Our findings suggested that while the widowed were diagnosed at an older age and with slightly more severe symptoms compared to the other groups, the never married and divorced did not differ from the married on the age or severity of impairment at the time of diagnosis.
Individuals may be unaware of their symptoms, particularly in the early stages of dementia. The subtle prodromal changes associated with cognitive impairment and dementia, such as memory, personality, and behavior changes are frequently first reported by partners/spouses. Thus, married individuals might be more likely to seek dementia evaluation and to be diagnosed at an earlier stage compared to those who are unmarried.
However, the participants in the NACC study were evaluated each year with rigorous standardized testing at clinics specialized in dementia diagnosis. Thus, it is unlikely that there are substantial delays in diagnosis for the NACC participants. A delay in diagnosis might be more of an issue for prior studies that relied on health records, which partly depend on individual self-referral to their doctor, which may introduce biases in the timing of diagnosis.
The results of previous studies showing that marriage was protective could be explained by a delayed diagnosis for the married. For example, compared to unmarried individuals who need to be self-reliant to live independently, partners can compensate for cognitive impairment, delaying seeking care, which would result in delayed diagnosis.
Given that social connection is a known protective factor for cognitive health, do you think the observed differences in dementia risk are more about social support and relationship quality than marital status per se?
Within marriage, the health benefits appear to be present only in high-quality marriages. Indeed, in a study by Lawrance and colleagues (2019) individuals who are unhappy in their marriage, an indicator of marital quality, are more likely to have equal or worse health and mortality risk compared to those who are widowed, divorced, or never-married counterparts. In line with this, a recent study from our research team found that on days when participants were more satisfied with their relationships, they felt healthier and reported sharper minds, better memory, and clearer thinking. Examining the association by considering marital status duration (e.g., timing of marital loss) and incorporating other relationship factors (e.g., relationship satisfaction) is needed to fully understand the connection between marital status and risk of dementia.
What are the broader implications of your findings for public health or dementia prevention strategies? (Could these results shift how we think about social connection and cognitive aging beyond marital status?)
Our findings highlight that marriage itself may not be a universally protective factor for health, as traditionally believed. Given that nearly half of all dementia cases worldwide could be prevented or delayed by addressing 14 modifiable risk factors, it is critical to identify older adults who are vulnerable to developing dementia. Our findings suggest that married individuals may be at higher (not lower) risk and could benefit from closer monitoring and support.
What other questions are you currently exploring in your research? Are there follow-up studies or related areas of aging and brain health you’re particularly excited about?
Our recent research focuses on investigating the link between life satisfaction, a crucial component of well-being, and the risk of dementia among older adults. We provided consistent evidence that life satisfaction is associated with a lower risk of dementia, and that this protective effect is robust across world regions, persisting even after accounting for well-established dementia risk factors (e.g., age, sex, education, depression, diabetes, smoking). Our next step is to investigate the association between marital status and dementia in other samples to replicate and evaluate the generalizability of the findings. Additionally, since the health benefits of marriage appear to occur only in high-quality relationships, we aim to examine the role of relationship quality on cognitive outcomes.
You can read the full study here.
In addition to “Marriage doesn’t help prevent dementia afterall” you may want to check out these other Q/As in the blog!
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Leave a comment below: What are your thoughts on the idea that marriage doesn’t help prevent dementia?