Julia McQuillan, PhD, on Association of Depressive Symptoms with RA

Dr Julia McQuillian, the Willa Cather Professor of Sociology at the University of Nebraska in Lincoln, shared some details of her research with colleagues in the field of sociology into the association of depressive symptoms with rheumatoid arthritis according to race/ethnicity, gender, and education.

Dr McQuillan and colleagues conducted a study examining the association between rheumatoid arthritis and depressive symptoms, specifically looking for differences by education, race or ethnicity, and gender.

Rheumatology & Arthritis Learning Network:   What prompted you and your colleagues all in the field of sociology to undertake this research into depressive symptoms and rheumatoid arthritis?

Dr. McQuillan:  This project actually started in the 1990s when I was a graduate student, research assistant on the National Rheumatoid Arthritis Study at the University of Connecticut. I joined when they were in the fifth of 10 years of data collection. It was designed by 2 sociologists, Judith Fifield and Susan Reisine, who worked with pharmacologists and rheumatologists.

We did a study that looked at how depression and anxiety could influence the trajectory of arthritis symptoms, and I was doing research on depression as an outcome. I was very curious if the association could also be reversed. If you have worse symptoms, could you have worse depression?

But then when I started at University of Nebraska, I got very involved in other research projects. This one, I picked up again when I taught a class on multilevel models. Jeff Willett was a student then. He now works at the American Heart Association. Then he got a job quickly, we never finished it.

Then a couple years ago, my daughter was diagnosed with rheumatoid arthritis. I saw the impact it had on her life. She's 19 now, but she was 15 when she was diagnosed and she had to drop out of marching band, and it really had a big impact on her life. I thought, "I need to pick that project back up."

I had a student who was starting a job at a medical school in Arkansas and she really understood how to frame an article for a medical audience who worked with doctors, and then another former student worked at the Agency for Health Research Quality. She said, "This is really important topic right now with social determinants of health." We picked the project back up and finished it.

RALN:  Would you give us an overview of how you structured your study?

Dr. McQuillan:  Sure. The dataset that we had has collected data over 10 years. Two of the years, they didn't have some of the questions we needed. The data is structured so that each year — we have the same people —their data is stacked one on top of the other, so we can follow them over time.

That's a wonderful resource to answer questions about when people change their pain or disability— is that associated with a change in depressive symptoms. It's also quite complicated to analyze because when you look at the same person over time, their scores are going to be more highly correlated with their prior scores, so you have to adjust for that. It's called autocorrelation.

It also allows us to compare— it started with 988 people — differences between people that are stable, things like their gender identification, race/ethnicity, or their level of education as an adult, and see if the way changes over time and their RA symptoms are associated with their depressive symptoms might be different between people.

We estimated people within-person changes over time. Most people would understand the multiple regression-type analysis in this audience, so looking at basically y-axis would be depressive symptoms, and the x-axis, this would be over time. We've estimated a trend line for each person, and then we aggregate that. We say, "How do those trend lines—are they similar or different between people?"

It's a within-person analysis change over time and a between-person analysis would be stable characteristics such as your initial age in the study, your gender, your education, your race, ethnicity.

Within people, we looked at how they vary around their own mean. We did a program that estimates the functional disability or the mean pain and then looks at if you vary around your own mean, is that associated with changes in depression?

We also looked at how people differ between them. Some people start with high or lower education. Some people are men or women. Some people are racial, ethnic minorities, or not. That allows us to have a very powerful way to differentiate the within-person change over time and differences between people.

RALN:  What did you find out about the differences among patients by education, gender, race, or ethnicity in terms of their experience with depressive symptoms and rheumatoid arthritis?

Dr. McQuillan:  When pain and disability increase, there are increases in depressive symptoms. What we expected to find there, we did find and that persisted even when we adjusted for things like how long you've been living with RA. We did also find that people experience a lot of change in depressive symptoms, pain and functional disability, and housework disability over the study period.

One advantage of this study—the people that designed it recognized that most people with rheumatoid arthritis are women, and some of the conventional measures in the 1980s, when the study started, didn't take into account things like challenges to do housework. That might be more salient for women than men, given our expectations in the US about who does housework, especially in the 1980s.

There were a lot of changes over time. We did find that depressive symptoms did increase over time. The rate of change, however, was not different by level of education, race, ethnicity, nor gender. So it seemed to be that it doesn't matter your social location, if you have worse pain, worse symptoms, you have higher depressive symptoms.

But it's not deterministic. It's not everybody, but the average that's the tendency. The times of worse pain, functional disability, and household disability were associated with worse depressive symptoms. Functional disability, however, that association with depressive symptoms was worse for men than for women. This was interesting, because from a sociological perspective, usually women are the ones that are worse off. Women do start with higher depressive symptoms.

We might find some differences. We argue in the paper that we should collect new data to see what the contemporary situation is because there's no study like this, no huge study of starting with 988 rheumatology patients across the nation, following them for 10 years.

We also might collect information about substance abuse or other kinds of coping or lack of coping that will result in different kinds of struggles such as depression. Sometimes, you capture different things with men and women, but for men, functional disabilities seem to have even more of a negative consequences for depressive symptoms.

We hypothesize, maybe that's because, for men, physical functioning is really important for the kinds of jobs many men have, if you're working in a place that requires physical labor. For men's identity, a lot of that can be wrapped up with their ability to do physical labor and physical tasks.

From a sociological perspective, we think about, "What does it mean for my identity? What does it mean for my social roles?" Either men or women could have a similar functional impairment. It might mean something different for men. We'd love to see more research, actually interviewing men and finding out what does it mean. They might not be able to articulate it the way we do, thinking about identity or roles, but they could talk about, it's really embarrassing to not be able to do the things they used to do like mow the lawn.

We thought that was important for providers to think about because they might just look at their pain but not think about, "What does this mean for my life?" It also might not ask men about depression because it tends to be something we associate with women. We thought that was an important finding.

RALN:  You also noted that depressive symptoms were driven more by differences between people compared to changes within people over time. What kind of differences between people did you find?

Dr. McQuillan:  I wanted to note that we didn't find some expected findings like differences by race/ethnicity, which we expected because of historical racism and differences in resources. Maybe that is because we adjusted for resources, also because we have very small numbers, which might reflect access to specialty care of the 1980s.

What we mean by within and between is that if you simply take that data that I described it stacked and you say, "OK, how much within a person over time did they deviate from their mean?" People do vary around that mean but not as much as if you looked at maybe comparing men and women and depression at the beginning or comparing depression by education, the education gradient in depression.

Those were bigger—you're starting social location. That was a bigger difference in depressive symptoms that people varying over time; 35% of the variance and depressive symptoms is within, and 65% between. If you look at by education, as education increases, depressive symptoms go down substantially—almost half the average depression. So initial education is a major factor in depressive symptoms initially. We would argue that that has to do with social resources. The more educated you are, you might have a type of job that allows you to live with RA, also more coping resources to understand what's going on, access to medical care.

There's small difference in race /ethnicity, so White people have lower depressive symptoms. The people of color, 2 symptoms out of 60. And then for gender, women are a little bit higher than men. It's a difference of, on average, 13 for women and 10 for men. So education is a major factor shaping the between differences that we find initially.

RALN:  Taking all this into consideration, if a practicing rheumatologist takes all this information into account, how does that help them make determinations about what they should do in terms of monitoring mental health of their patients with RA and helping those patients find mental health care?

Dr. McQuillan:  This is a great question. It's a very important question. When I worked at a hospital in Connecticut, where we were working with rheumatologists, this question came up a lot, "How can we actually put this in practice?"

We had done a study comparing different measures of depressive symptoms for people with arthritis to make sure that those items could effectively differentiate who was depressed and who wasn't — we also looked at clinical anxiety — using a short form. The clinical interview that a psychiatrist uses quite long and quite complicated to score. We had some measures that had 20 items or even 10 items.

What we found is that there was a subscale of about 5 items called depressive affect. That was quite good at differentiating between people who met clinical criteria and people who did not. We've proposed having those 5 questions on the intake form. If they look elevated to recommend to treat the depression and anxiety; you can help people's response to their stress and inflammation be better.

You can help the arthritis by helping somebody get care by psychiatrists possibly getting on some kind of pharmacological treatment. Because, at least at the time when this data is collected, many people had a rheumatologist and didn't see their primary care physician, the rheumatologist might miss the depressive symptoms, but a short checklist might help.

That's one of the things that we suggested, and there's a lot of work happening to destigmatize mental health issues and see it as another health condition, like other health conditions, and that could also be a part of it. By having the rheumatologist or physician treat this as another health condition, you can see another specialist and that it would help with your overall health to have a mental health treatment. Also, some work on group-based coping, so help people finding others with arthritis and how they cope and how they manage that.

Not assuming that people's gender, or education, or race/ethnicity would be the...it's confusing because I've said education matters, but don't assume that someone who's highly educated isn't depressed, or someone who is White isn't depressed, or who are men are not depressed just because on average, they have lower scores.

It's complicated because sociologists use population data. We talk about these big trends. Physicians treat one person. It's hard to see ecological fallacy to go from major aggregated data, population data, and when you're treating one person. That's where I would say a screening would come in handy so that you treat every patient initially the same.

You also would want to do that repeatedly because what we found is that depressive symptoms can change over time. If people have elevated pain and impairment to also maybe ask a few questions about difficulty getting going, having a sense of self-worth be affected and just normalizing that as part of the visit is what I would recommend.

I would love to see more research. I'm nervous, because sometimes what seems logical can have unintended consequences. I would love to see a study done on, "Does that work in practice?" I don't want to assume that it would, but that would be one suggestion to explore. I would love to partner with physicians to look at something like that because I think it has potential.

Maybe they're already doing that. I don't know if they are. Maybe, some are already recognized that helping their patients deal with depression and anxiety helps their overall health, fewer symptoms, fewer flares, that are coping, able to stay employed. Research that my colleagues did at University of Connecticut showed that helping people stay employed helps their arthritis symptoms, helps them to move, social support helping with them. It's complex. I'm really grateful for the rheumatologists who deal with this really hard chronic condition that we can't cure it, but you can help people live with it.

RALN:  Thanks again for joining us today, Dr. McQuillan. We appreciate your insights into this very interesting subject.

Reference:

McQuillan JT, Andersen JA, Berdahl TA, Willett J. Associations of rheumatoid arthritis and depressive symptoms over time: are there differences by education, race/ethnicity, and gender? Arthritis Care Res  Published online ahead of print June 13, 2021. https://doi.org/10.1002/acr.24730