On this World Health Day, with a focus on depression, I am struck by the simple fact that everybody knows a little something about this common condition. Whether it’s through first-hand experience, or witnessing a family member or friend struggle with the disorder, depression touches each of us in some form. And despite the increased rate of depression globally, there’s reason to believe newer and more effective treatment options are on the horizon.
Brain research has entered a new era of understanding the biological mechanisms that put people at risk for depression. Identifying the genetic origins of developmental brain disorders is catalyzing new approaches to the way we study, treat and prevent depression. For centuries, we have known depression in terms of how it looks and how it feels, but we have not known at a basic level of brain science, what it is. Last year 23andMe, the personal genetics company helping to lead the effort to better understand the human genome, identified 15 genes associated with risk for developing major depression. Genes are mechanisms of disease, not necessarily the only mechanisms or even necessarily the most important, but they are the first objective clues to what’s behind these disorders. This is a huge step towards understanding both the origins and risks associated with depression, and to convert this knowledge into better prevention and treatment approaches, we must invest in studying the organ that underlies depression, that is the human brain.
Treating mental illness has never been easy and research moves forward slowly because we lack an understanding of the causes and mechanisms behind these conditions and we don’t have enough brains to answer these questions. When studying depression and other mental illnesses like schizophrenia, autism, or opioid addiction, we are studying brain diseases. And to understand brain disease, there is no substitute for human brain tissue—not animal brains, not blood samples, nor behavioral studies. Examining human brains helps us identify molecular pathways that may contribute to disease just like studying the human heart helps understand how heart attacks happen.
One of the most obvious challenges facing the research community is money – cutting edge science and drug development is expensive and high risk. Collecting and conducting molecular genetics on human postmortem brain tissue is a huge, but critical, investment of resources and requires. In the past, research studies could be published by comparing differences between 20 people with mental illness against 20 without. But rigorous research requires many more samples, perhaps 1000s or more, necessitating even more donations to ensure the studies are powerful enough to give us important answers and potential breakthroughs.
The global cost of mental illness was estimated at $2.5 trillion in 2010. Even more astounding is the global burden of mental disorders, estimated to be higher than cancer and heart disease combined. These costs are projected to climb to $6 trillion by 2030. If we expect to lower these costs to society and find new treatments for disorders as far reaching as depression, we have to begin by spending more money on brain research to get at the root cause of these problems.