On the 26th of March 2018, we held our second multi-disciplinary seminar in the series on social relationships and health across the life-course, funded by the Grand Challenges. Building on our first seminar focused on young people, the second seminar moved on to looking at social relationships and health in mid-adulthood and old age.
Our first speaker, Dr Robert Meadows from the University of Surrey, discussed his research on the association between social relationships, sleep and health. Dr Meadows began by discussing the explicit and implicit negotiations that occur in relationships regarding sleeping arrangements. A key theme highlighted was the ‘uneasy balance’, in which sharing a bed with a partner can have both positive and negative impacts on health. For instance, sharing a bed can have psychological benefits such as feelings of safety and closeness, but on the other hand it can also have negative effects on sleep quality (for example, related to snoring and waking during the night). Dr Meadows also emphasised the gendered nature of sleeping arrangements that often occurs, particularly when caring for children or older relatives is involved. It is often tacitly assumed that women will take responsibility for waking during the night for caring purposes, leading to more sleep disturbance.
Dr Meadows also discussed a recent study conducted by his team to examine whether sleep mediates the association between marital status and health. In a cross-sectional study using Understanding Society data, the researchers found more sleep problems in all groups compared to married people with little-to-no relationship distress. Sleep appeared to mediate the relationship between marital status and sleep. Dr Meadows discussed several potential explanations of this finding. On the one hand, the finding could be explained by better health leading to a greater likelihood of marriage. Or it could be that marriage itself leads to better health. Perhaps the symbolic meaning of marriage can encourage us to stay healthier and to exert control over health behaviours. Or our spouse may have a direct impact on health, for example, by encouraging us to visit a doctor and to eat more healthily. Dr Meadows highlighted the need for further longitudinal research in this area to gain insight into whether sleep problems precede marital problems or vice versa.
Our second speaker, Dr Andrew Sommerlad from the UCL Division of Psychiatry, discussed his epidemiological research on social engagement and dementia risk. The focus was on teasing apart the relationship between these variables and examining whether: 1) low social engagement is a risk factor for dementia, 2) low social engagement is part of the dementia prodrome, or 3) a reciprocal relationship is present.
First, Dr Sommerlad discussed his recently published systematic review (http://jnnp.bmj.com/content/89/3/231) focused on the association between marital status and dementia. The review identified 15 papers (after screening 883) with varying study designs. The researchers found that widowed and life-long single people had increased risk of dementia compared to those who were married, with no difference seen for those who were divorced. Lower education levels partly explained the increased risk seen in relation to widowhood, and poorer physical health partly explained the higher risk in the lifelong single group. Dr Sommerlad discussed several potential explanations for these results, including the possibility that being married increases exposure to protective factors, such as having a healthy lifestyle. Alternatively, underlying cognitive traits might explain both reduced likelihood of marrying (at a time when marrying was the norm), and increased risk of dementia risk. Bereavement could increase risk of dementia through the negative effects of stress on the brain. Further research is needed to examine these potential mechanisms, taking into account other potential confounders which could not be examined in this review.
Next, Dr Sommerlad discussed his recently conducted longitudinal study using the Whitehall cohort, with nearly 30 years of follow-up. The Whitehall study includes measures of social contact, social activities and cognitive function, while dementia was assessed through hospital records. The researchers looked at the association between social contact and time-to-dementia, adjusting for possible confounders. Self-reported social contact was not found to be associated with dementia risk until five years before diagnosis. Social contact was associated with higher baseline cognitive function, but not with cognitive change. The researchers interpreted this as consistent with the hypothesis that social decline may be part of the dementia prodrome. However, they noted that it is possible that the study may not have fully captured lifetime social contact. Dr Sommerlad highlighted the importance of further research in this area, including the need to develop more sensitive measures of social engagement. He also emphasized the need for awareness of social disengagement as an early marker of dementia.
The seminar ended with a lively discussion about broader topics in social relationships and health in adulthood, stemming from the two presentations. Interestingly, there were several points of overlap between the two talks. For instance, both speakers focused specifically on marital status, and there was discussion about whether sleep quality could play a role in the association between marital status and dementia risk (given that sleep quality is associated with both marital status and dementia). Both speakers emphasised the challenges of measuring social relationships and the need for a better understanding of this. Our final seminar in the series will address this important topic, with experts in the field discussing challenges and current research in the measurement of social relationships.
SOCCAH 