To improve mental health, focus on population health, prevention
October 8, 2024 – Throughout the fall, Harvard Chan faculty will share evidence-based recommendations on urgent public health issues facing the next U.S. administration. Karestan Koenen, professor of psychiatric epidemiology and head of the Population Mental Health Lab, offered her thoughts on policies to reduce the prevalence of mental health problems, which will affect roughly a third of people during their lifetimes and which have been shown to increase the risk of chronic diseases as well as hamper success in education, employment, and relationships.
Q: Why is mental health a pressing public health issue?
A: We’ve known for a long time that mental health problems and mental disorders are very common. The CDC [Centers for Disease Control and Prevention] estimates that about 1 in 3 people will have a mental disorder at some point in their lives, and that, currently, 1 in 5 have a diagnosable mental disorder.
We know that mental health is the foundation for physical health. We know that people with mental health problems die younger; are at greater risk of all the major chronic diseases such as cardiovascular disease, diabetes, and cancer; and that if they get cancer and are treated for it, they’re less likely to have a good outcome.
We also know that mental health problems start earlier in life than any other chronic disease—most start in childhood or adolescence—and mental health relates to all aspects of life. Having mental health problems decreases the likelihood of someone finishing high school or college, of being able to be employed, of being able to stay in a stable relationship, of managing money.
Q: What are the biggest challenges facing the next administration around mental health?
A: Normally, when people focus on addressing the mental health crisis, they immediately look to increasing access to treatment—given that it’s very hard to find a mental health provider when you need one—and improving treatments. Those are two really important areas, but I think we’ve known for a long time that, given the scope of the problem, that’s not going to cut it. I think we need a more population-based, public health approach.
Think about how we’ve dealt with motor vehicle-related deaths. For a while now, even though the number of miles that people have driven has increased, motor vehicle-related deaths have decreased. Did we do this by getting every individual a private driving instructor or a driving coach? No—we decreased these deaths by population-based public health interventions like cracking down on drunk driving, changing speed limits, setting regulations around car safety, making it more attractive to pay more for a safe car, raising the driving age, and restricting teen driving.
We need to think about mental health the same way—by focusing on population health and on prevention. The challenge is that we’re still focused on this very old-school idea of treatment, where an individual psychologist or social worker meets in an office with an individual. It’s not that some people won’t need medication or an individual therapist. But our idea of what an intervention is needs to expand. For example, there’s pretty good evidence that certain forms of exercise and specific kinds of mindfulness practices can reduce depression.
Q: What are your top two or three recommendations for policies that might address mental health?
A: Any kind of economic policy that reduces stress on families would improve mental health—for example, paid family and parental leave policies, policies that reduce food insecurity, and policies to reduce home foreclosures in order to help people stay in their homes.
Q: What’s the evidence supporting those recommendations?
A: There is a ton of evidence that economic stress is related to worse mental health.
Work by my colleague Rita Hamad [associate professor of social and behavioral sciences] has shown how changes in economic policy may improve or shift the curve in mental health. One of her studies showed that, when Congress temporarily expanded the Child Tax Credit during the COVID-19 pandemic, the increased income for low-income families improved parents’ mental health.
A 2015 study found that people who went through home foreclosures during the recession of 2007-09 experienced increased anxiety and depression. The authors suggested that interventions to prevent foreclosures could benefit both physical and mental health.
A 2020 study found that paid maternity leave is linked with beneficial effects on both the mental and physical health of mothers and children, as well as on breastfeeding.
A 2022 study found that food insufficiency rose during the COVID pandemic, affected vulnerable populations, and was linked with symptoms of poor mental health. But that link was attenuated among people who received free groceries or meals.
There’s also a great paper from 2021 which suggested that distress during the pandemic, as measured by suicide help line calls, was mitigated by income support.
Q: What do you hope could be accomplished in improving mental health in the next four years?
A: I’d like to see people empowered with more knowledge about the things they can do to improve their mental health, whether it’s around diet, exercise, or meditation, or more traditional medication or therapeutic interventions. It would be good if people knew the whole range of options they have, as well as have more access to all these options.
There is robust evidence that time spent in green space and nature is beneficial for our mental health. For example, growing evidence suggests that the Japanese practice of forest bathing reduces symptoms of anxiety and depression. That means that policies to protect and expand our natural environment—such as protecting community parks, forests, and trees—are also mental health interventions.
I’d like to see us explore how technological advances can be used to improve mental health care and population mental health. For example, Vikram Patel [Paul Farmer Professor and Chair of the Department of Global Health and Social Medicine at Harvard Medical School and professor in the Department of Global Health and Population at Harvard Chan School] is using technology to improve mental health care through the EMPOWER program, which offers a suite of digital tools aimed at training health care workers to provide mental health care. A lot of people, including John Touros [director of the Division of Digital Psychiatry at Beth Israel Deaconess Medical Center] and others at Harvard, are using technology to address suicidal thoughts and behaviors. And one of my colleagues, Kristina Korte [instructor in the Department of Epidemiology], is leading a study in Kenya to test an app-based intervention aimed at treating posttraumatic stress disorder (PTSD) by teaching emotion regulation and interpersonal skills. This sort of intervention could be beneficial in a place like Kenya, where people have smartphones but where there are a limited number of mental health clinicians.
I would also like to see mental health get the same priority and attention that other areas get. If you look at funding for something like cardiovascular disease or cancer, it dwarfs funding for mental health. We have 50 years of epidemiology on how big the mental health problem is. The government could definitely provide more funding in this area, including toward research and increasing access to care.
Nov. 15 update: The 18th Kolokotrones Symposium—“Causal Inference for Population Mental Health”—held Nov. 15, was the official launch day for the Population Mental Health Lab, which co-hosted the event with CAUSALab.
