In this episode of Frontiers in Health & Happiness, I explore the intersection of loneliness and health equity with Dr. Koichiro Shiba, Assistant Professor of Epidemiology at Boston University. Dr. Shiba discusses the significant effects of social isolation on mental, physical, and cognitive health, particularly among marginalized communities. He advocates for population-level interventions to promote social connectedness and reduce health disparities.
Ayla Fudala: Hello and welcome to Frontiers in Health & Happiness, the official podcast of the Lee Kum Sheung Center for Health and Happiness at the Harvard T.H. Chan School of Public Health. My name is Ayla Fudala, Center Communications Coordinator, and I'll be asking experts how to live a healthy and happy life.
Did you know that loneliness can affect some people more than others? In the third installment of our loneliness and Well-Being series will be focusing on the intersection of loneliness and health equity. To explore this connection, I sat down with Doctor Koichi Chiba, an assistant professor of epidemiology at Boston University and a Harvard T.H. Chan School of Public Health alum.
Ayla Fudala: My first question for Dr. Shiba was: why should we care about the loneliness issue?
Dr. Koichiro Shiba: There's a lot of evidence suggesting that social disconnectedness, isolation, and loneliness impact our mental health and psychological well-being. But also there is another line of evidence saying that disconnectedness can negatively impact our physical and cognitive health. So basically, disconnectedness can influence many aspects of our health and well-being. So that's one reason why we should care about social connectedness. Now, another reason why you should care about disconnectedness is that it can cause some societal impacts. For example, a disconnectedness can deteriorate our societies economic outcomes. It can also lower neighborhood safety levels. A lower connection in a society could reduce disaster preparedness and the resilience of a community, which in turn might influence many health and economic outcomes in the time of crisis. Social disconnectedness can introduce many negative adverse consequences that we want to avoid.
Ayla Fudala: How does loneliness affect different people in different ways?
Dr. Koichiro Shiba: There are two things to consider. Social isolation itself is socially patterned, meaning that people from socially marginalized groups are more likely to experience social isolation. So there is a disparity and isolation itself, but also its impact on health is socially patterned.
I just mentioned that social isolation can influence our health, but the effect, its effect on health can be different across individuals, and people from socially marginalized backgrounds may be more likely to be damaged by the social isolation experience. So what that means is that if we don't address this problem of social isolation, people from marginalized backgrounds, first of all, are more likely to be exposed to isolation, and also they're more likely to be damaged by isolation. Therefore, it might reinforce the existing disparities in many health outcomes.
Ayla Fudala: Why do you think some people are more negatively impacted by social isolation than others? Do you have any theories on why this might be the case?
Dr. Koichiro Shiba: There are many possible reasons, but one of the reasons that I can think of now is that, for example, those people from socially marginalized backgrounds tend to lack resources that they need to cope with psychological distress that could arise from being socially disconnected and isolated.
Ayla Fudala: So how can we address this inequity? Would promoting social connection also promote health equity and if so, how?
Dr. Koichiro Shiba: I think that promoting social connectedness can enhance health equity and address this issue of health disparities. And the reason is that, like I mentioned earlier, social isolation itself is socially patterned. People from marginalized backgrounds are more likely to experience isolation. Therefore, if we could do an intervention that removes social isolation from the population, those people tend to benefit more from the intervention. And also, like I mentioned earlier, um, social isolation affects health with a greater magnitude among people from socially marginalized backgrounds. And therefore, in this case, if we intervene in social isolation and remove that from the population, again, those people benefit more. So promoting social connectedness at the societal level has the potential to reduce existing health disparities in our society.
Ayla Fudala: In your work, you advocate for a population level rather than individual level approach to promoting social connectedness. Can you explain what exactly that approach would entail?
Dr. Koichiro Shiba: When I say population approach to promote social connectedness, what I mean is to shift the entire distribution of social connectedness in a society instead of treating a limited number of people who are isolated. This kind of population level approach. There are many ways to do that. And one example might be to build community-based places, right. And so, for example, in Japan, um, the Japanese government is encouraging local communities to open community-based gathering places where all adults can congregate. And we we conducted empirical study looking at its impacts on people's health and well-being. And we found that opening the new community-based places and participating in those places can have positive impacts on our first, both social connectedness but also our health and well-being outcomes.
Ayla Fudala: Can you tell me about your work with causal inference?
Dr. Koichiro Shiba: To give you some backgrounds. For those who are not familiar with this idea of causal inference. Causal inference is a technique that epidemiologists tend to use to tease out causal effect from statistical association. Now, when we use causal inference, what we are really estimating is the contrast of two population averages of health. So comparing. It's really telling us how changing the level of an exposure might influence the average in population health. Now um, this paradigm in causal inference, although it's very useful and it's been used to inform many decision makers, it's lacking an important perspective, which is that how the intervention might influence the distribution of health in the population, namely disparities in the health outcome. So I think there is a huge gap there, methodologically speaking, and we need a method to quantify the expected changes in health disparities that we would observe under a hypothetical intervention, uh, targeting an exposure of interest.
Ayla Fudala: Your most recent research projects simulated changes in income based disparities in cognitive functioning among older adults under hypothetical population interventions addressing social isolation. The simulation asked the question would population level interventions to reduce social isolation also reduce disparities in cognitive function? What was the answer?
Dr. Koichiro Shiba: Based on what we found, the answer is likely yes. Reducing social isolation appears to be reducing disparities in cognitive functioning in the data we used, which is the sample of older adults in the US. But there is some nuance to it. So in this study, we simulated several intervention scenarios where we manipulated the distribution of social isolation in the population. Now, if the hypothetical intervention did not address the existing disparity in social isolation, right. So the intervention reduced social isolation overall in the population, but it maintained the social disparity in the exposure, which is isolation, that hypothetical intervention did not substantially reduce it disparity in cognitive functioning. So it really depends on how you intervene in social isolation and how you reduce it in the population. And depending on how you do it, the implications of the intervention on health disparities might be different.
Ayla Fudala: What were the associations between income, social isolation, and cognitive functioning?
Dr. Koichiro Shiba: In this data of, again, um, older adults in the US, we found that there is income-based disparity in both the exposure and the outcome, meaning that there is an income based disparity in social isolation. And the higher the income was less likely to experience social isolation. We also found income-based disparities in cognitive functioning. Again, um, there we found that higher income was associated with higher cognitive functioning. So for both isolation and cognitive functioning, we found evidence of income based disparity, at least in our study population.
Ayla Fudala: Why do you think higher income meant lower social isolation and higher cognitive functioning? Do you have any ideas that could explain this correlation?
Dr. Koichiro Shiba: For social isolation, in order for you to be connected with others, you need time. And it's often the case that people earning a lot, they actually have time, spare time to spend to stay connected with their friends and families and, you know, to drink and engage in social activities in the community, stuff like that. Um, so in that regard, like, um, higher income people are more likely to maintain their connections with peers with regard to the outcome, cognitive functioning. We don't know how that disparity was shaped. And maybe part of that was the causal relationship where people with higher cognitive functioning were able to make a lot of money, uh, so that could be part of it. But also like if you were to maintain your cognitive functioning, you need a lot of resources. You need to engage in, you know, intellectual activities you need you may need some health promoting resources and the something you can afford with money. And that could explain that disparity in cognitive functioning that we observed in the data.
Ayla Fudala: Do you think social connection is the solution to the loneliness epidemic?
Dr. Koichiro Shiba: If you mean social isolation or structural aspect of social connectedness, then yes, promoting structural aspect of social connectedness, for example, facilitating, you know, social interactions between people, um, designing a place where people can congregate and make new friends that can promote the structural aspect of social connectedness, which in turn might reduce loneliness. But at the same time, some people may feel lonely, even if they are connected to people. So changing the structural aspect alone is not going to be magically eliminate loneliness. And it's a very difficult task.
Promoting connectedness at the community level with societal level can have another impact on loneliness. So it's not just about yourself being connected with someone, you feel less lonely. It's not just like that. If you live in a community where people are strongly connected, then that might also influence your level of loneliness. So promoting connectedness at the societal level might be another solution to tackle the problem of loneliness epidemic.
Ayla Fudala: Finding solutions to the loneliness issue is crucial to public health. Could you share some of the most promising interventions to promote social connection that you've come across in your research?
Dr. Koichiro Shiba: I conducted several studies looking at the actions to promote social connectedness and its impacts on health. One very promising approach was to build a community-based places for older adults to mingle with their peers. Participating in those places and activities appear to be promoting social connectedness among participants and also promoting their health and well-being. So I think that is one very promising approach to promote social connectedness, and that is based on scientific evidence.
One of the pathways linking social connectedness and our health is not just about the sense of loneliness and psychological distress, for example, um, connectedness can bring us a purpose in life, which can which can also influence our health and outcome. And in these community-based places in Japan, for older adults, they sometimes interact with local kids. So there are some intergenerational interaction going on. And through the intergenerational interactions, some older adults gain a purpose in life, meaning in life, and that could influence their health outcomes.
Ayla Fudala: How can we as individuals promote social connection in our day to day lives?
Dr. Koichiro Shiba: I mean, that really depends on the person, right? People have different lives and different styles of communicating with people. It's important to have at least opportunities to be connected with others. I think it's important to address any structure barriers for individuals to stay connected so that they can try to stay connected, removing those barriers. So going back to the societal, the population perspective at least, ensuring that each individual has an opportunity to stay connected is an important thing that we should be doing as a society and as a public health community. And beyond that, individuals can do whatever they want to do. And you know, the approach is to stay connected. Again, it can vary across individuals.
Ayla Fudala: What should policymakers be doing to promote social connection and address health disparities within the issue of loneliness?
Dr. Koichiro Shiba: Social connectedness is a health promoting factor and also it can influence many important societal outcomes. So when they plan policies and actions, they need to keep in mind that they need to think about how those actions and policies might influence people's connectedness. And what's the implication of that? I think decision-makers need to keep that in mind always.
Ayla Fudala: This is my final question: what are your plans for future research?
Dr. Koichiro Shiba: I think there are two lines of research. The first line is that I want to keep working on the work I talked about today, which is that how promoting social connectedness might influence health disparities that we have in a society. So that's one thing. Another thing is to look at social connectedness as an outcome, because we know that it's an important outcome if we know that it matters. It matters because it affects our health and other types of well-being. But also staying connected and having quality relationships with peers itself is an end play. It's something we want to pursue.
I want to work on research where we look at social connectedness as an outcome. What's the determinant of social connectedness? How is social connectedness distributed across the population? How is it changing over time? What's the inequality in social connectedness? That line of research I think is very important, and that is something I want to work on.
Ayla Fudala: Dr. Shiba's research at the intersection of social isolation, health disparities, and methodology has introduced new considerations to the study and prevention of social isolation by exploring the associations between social isolation, socioeconomic status, and cognitive functioning. He has drawn attention to the health disparities present in our society by developing an innovative new analytical framework. He has provided a tool which researchers can use to incorporate the consideration of health disparities into their work, and by advocating for a population level focus in interventions and urging policymakers to use social connection as a fundamental health promoting factor. Doctor Shiba has illuminated a clear path towards the promotion of health equity and social connection.
In the next installment of our Loneliness and Well-being series, I'll be speaking with Dr. Jeffrey Hall, an expert in the intersection of social media and loneliness. Dr. Hall is a Professor of Communication Studies at the University of Kansas, and formerly served as a visiting scholar at the Berkman Klein Center for Internet and Society at the Harvard Law School.
New episodes in our Loneliness and Well-being series will air every two weeks. Episodes can be found on the Lee Kum Sheung Center for Health and Happiness website and YouTube channel, as well as on Spotify, Apple Podcasts and wherever else podcasts are found. Thank you for listening.