The World Health Organization defineshealth as “a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.” Over the years, public health has made great strides towards improving the health of populations, yet many key health achievements—from vaccination, to better sanitary conditions, to improved traffic safety—have been in the area of physical health alone. Too often, mental health, and the prevention of mental illness, has been an underappreciated public health challenge. At SPH, we have worked to correct this, by doing our part to elevate mental health to the same level of attention as physical health. We are, for example, one of the few schools of public health to offer a certificate in mental health and substance use. Mental health is truly a “first principle” of public health. Simply put, we must apply to the conditions that shape mental health the same population health approach we currently apply to the drivers of physical health. We cannot be healthy if we do not address these conditions, and the stigma that can prevent an honest discussion about mental illness.
Why Mental Health?
The reasons why mental health should be at the core of a concern with the health of populations are legion. I submit two key reasons, both of which are simple, compelling, and amply sufficient for a call to action.
First, the absolute burden of mental illness is staggering. WHO estimates that about 14 percent of the global burden of all disease can be attributed to mental, neurological, or substance use disorders. Among the civilian population, the National Comorbidity Survey estimated the lifetime prevalence of major depressive disorder in adults to be about 17 percent, and that of any anxiety disorder to be about 29 percent. In any given year, about 9 percent of US adults meet criteria for current depression. A 1 in 10 prevalence of a major debilitating disorder such as major depressive disorder is remarkably high; about 31 million Americans will have depression at any one time. By way of comparison, about 200,000 Americans are diagnosed with lung cancer annually. Considering one consequence of mental illness, suicide, brings the burden more clearly “home.” There are more than 800,000 suicides a year globally, and the US now sees more deaths by suicide than by traffic accidents. Since 2012, more US soldiers have died from suicide than from combat. It is additionally clear that mental disorders increase the risk of other health conditions and worsen outcomes for comorbid conditions, further compounding the burden of mental disorders. Insofar as tobacco-related diseases are a consequence of nicotine addiction—itself a mental disorder—mental illness is at least in part responsible for a broad range of consequences of tobacco use.
Second, mental illnesses have a much earlier onset than many other chronic diseases. According to the National Comorbidity Survey, the disorder-specific median ages of onset of mental illnesses are all below age 33, with the overall median age of any disorder onset being 14. Compare this to the median age of onset of diabetes, 54, or the average age of first heart attack in men in the US, 65. Although these latter conditions take a toll on the older population, mental health problems tend to begin much younger: For example, suicide, 90 percent of which is linked to a mental health problem, is the second leading cause of death globally among 15- to 29-year-olds.
Public Health and Mental Health
A sobering observation when considering the burden of mental illness in populations is that the relative dent we have made in the consequences of many forms of mental illness remains small. What is perhaps most striking about the suicide is how unyielding the suicide rate in the US has been over the past decades. [See Figure 1.]
Figure 1
Courtesy of the American Foundation for Suicide Prevention
The challenge has not gone unnoticed, and there are two dominant strands in current thinking about approaches to mitigating the consequences of mental illness.
Thomas Insel, the the former director of the National Institutes of Mental Health, has spoken at length on this issue, suggesting that we start viewing mental illnesses as brain disorders in order to target risk factors in the brain before they manifest in behavior. Insel’s approach is grounded in, and concordant with, the dominant National Institutes of Health’s interest in an ever greater focus on personalized or precision medicine. This approach argues for a focus on genetics or other molecular approaches to detect brain disorders and mental illness earlier in their course.
A broader approach argues for the embedding of mental illness in the social structures that produce health generally and mental health specifically. Martin Prince and colleagues argue similarly for a focus on prevention, and additionally for a greater emphasis on the connectedness between physical and mental health. We have ample reason to be reminded that social conditions are inextricably linked to behavioral disorders. In some of our own work we have shown that behavioral disorders broadly are much more sensitive to social conditions than are other disorders, suggesting that an effort to mitigate the harm of mental illness must lie in the improvement of social conditions that shape the burden of mental disorders.
Prevention as a Key Element of Public Mental Health
Irrespective of potential approaches adopted, it seems clear to my mind that a prevention approach can be a critical component of a public health engagement with mental health. In many ways prevention is at the beating heart of pubic health, and an embrace of a population-based approach to the prevention of mental illness gives us both the remit and the charge to focus our efforts. To this end, together with a colleague, I have argued that a focus on prevention can catalyze a public health approach to mental health.
Prevention efforts have greatly reduced the prevalence of many communicable and non-communicable diseases worldwide. By contrast, prevention strategies for mental disorders remain in their infancy. We proposed that a lifecourse perspective could be the organizing principle around a public health approach to mental illness. A lifecourse approach to mental disorders accounts for the interplay of social and biological factors in the development and trajectories of mental disorders over the life span—from prenatal to old age. This approach can bring core foundational public health principles to bear to reduce overall incidence of mental disorders. Importantly, as a call to action, this aims to stand as a corrective to the oversight of mental health by many of us in the public health community. Absent an intellectual commitment to improving the science behind psychiatric prevention, our ability to prevent the incidence of mental disorders will continue to significantly lag behind our growing ability to prevent a range of illnesses, to the substantial detriment of the health of populations.
I hope everyone has a terrific week. Until next week.
Warm regards,
Sandro
Acknowledgement: I am grateful for the contributions of Laura Sampson and Eric DelGizzoto this Dean’s Note.