People who cohabit with a partner have lower blood sugar levels, even if they do not get along with them, according to a study that warns social isolation may increase the risk of type 2 diabetes.
The researchers believe that living with someone is an important source of social support for adults in mid to later life, according to the study published in the British Medical Journal’s diabetes journal. They found the effects were the same regardless of whether the relationship was harmonious or acrimonious.
The lead author, Katherine Ford, formerly of the University of Luxembourg and now at Carleton University in Ottawa, said: “Increased support for older adults who are experiencing the loss of a marital/cohabitating relationship through divorce or bereavement, as well as the dismantling of negative stereotypes around romantic relationships in later life, may be starting points for addressing health risks, more specifically deteriorating glycemic regulation, associated with marital transitions in older adults.”
The study builds on previous work that has identified health benefits from marriage and cohabiting, particularly for older adults, along with studies that have concluded that type 2 diabetes risk is associated with social isolation, loneliness and social network size.
The team from Luxembourg and Canada investigated if there was an association between marital status and marital quality with average glycemic levels in older adults, using biomarker data from the English Longitudinal Study of Ageing (ELSA). This is a sample of adults living in England aged 50 and older and their partners, who provide data biannually, of whom the researchers used data from 3,335 adults aged 50 to 89 without previously diagnosed diabetes between 2004 and 2013.
Participants gave blood samples to measure their average glycemic or blood glucose levels, and were asked whether they had a husband, wife or partner with whom they lived, along with questions to measure if the relationship was supportive or strained.
Information on several factors was also gathered such as details about age, income, employment, smoking, being physically active, depression, body mass index, and having other social relationship types in their social network (child, other immediate family, friend).
The study also tested the odds of prediabetes, which were lower among those who were married or cohabiting.
Analysis of the data over time showed that people whose relationships changed, for example through divorce, also experienced significant changes in their blood sugar levels and odds of pre-diabetes.
Surprisingly, the quality of the relationship did not make a significant difference to the average levels of blood glucose, suggesting that having a supportive or strained relationship was less important than just having a relationship at all.
As an observational study, the researchers said they were unable to establish cause, or, for example, whether people in worse health were more likely to get divorced.
Ford said the researchers treated marriage and a cohabitating partnership as the same, meaning they do not know whether marital status confers any benefits relative to living together. The research also did not explore the benefits of living with a friend or housemate, but Ford suspected that it “would not have the same effect” because housemates don’t necessarily “share in your life”, although she thought living with a friend may have benefits, depending on the closeness of the friendship.
