Advances in the Management of Depression - Episode 2
Michael E. Thase, MD: Most psychiatric illnesses are best understood as biopsychosocial phenomena, meaning that there are multiple pathways of causation. It’s not caused by a single gene. There is no depression gene. But if you have a first-degree relative who has depression—a parent, for example—your chances of having depression yourself are somewhere between 2 and 5 times greater than the average person of your age and socioeconomic group. So, it is familial.
And when you try to look at the different factors that go into causality, the familial relationship does account for a significant proportion of the variants. But it’s not perfectly familial, and it’s certainly not under single-gene heredity. For example, if I had an identical twin who suffered from depression, I wouldn’t have 100% certainty of suffering from depression myself, maybe only 70% to 80%.
Even when the genetics are identical, life experience, what you’ve gone through, can influence whether you’re at higher risk or lower risk. Now, it may well be that resilience factors are also inherited or acquired or taught. And so, one thing that might differentiate people who seem to be more depression-prone from people who are hardier in the face of depressogenic kinds of things—setbacks like losses, and disappointments, and bereavement, and so forth—may be how you’ve learned to handle your behavior and your feelings when you’re in a potentially depressogenic circumstance. When I got into this business 40 years ago, the notion that the activity of your genes could actually be modified for the rest of your life by things that you experienced seemed almost like science fiction. But we now know that there are these epigenetic factors that do influence whether genes are easily turned on or not able to be turned on. For example, early adversity, early trauma, in particular child abuse, or child neglect, or even sexual abuse can actually have stress-modifying effects on the activity of genes that may haunt or plague a person’s stress response for the rest of their life, or through key periods like adolescence and in young adults.
Another good example in terms of biopsychosocial factors is the value of social support in resilience. Having a loving significant other in your life who’s watching your back and who cares for you and who can hear your complaints and be a sounding board and so forth reduces your chances of getting depressed during a time of stress. Having no such person increases your chances.
Interestingly, one reason that women have a higher risk of depression versus men is that having a caring woman in your life is a protective factor. Having a caring man in your life doesn’t hurt, but it doesn’t offer quite the same protection. So heterosexual men have a relative advantage in this regard. There are many other factors that also explain sex differences in depression, including hormonal factors. Men are much less likely to have a depression after childbirth. Postpartum depression is a risk mostly carried by women, probably in part because of hormonal changes. There may be some increased risk at other reproductive times in a woman’s life. For example, during or following menopause. Men don’t have the same kind of age-dependent risks that women have.
Economic power and being on the receiving end of abusive behavior are other factors that partly account for gender differences and depression rates. Having economic power is somewhat protective against the risk of depression. Being on the receiving end of abuse and neglect is a risk factor and our society, at least, is not there in that regard.
Interestingly, if you look at the Old Order Amish around Lancaster, Pennsylvania, there is no gender difference related to the risk of depression. There are many reasons for this, but it does suggest that in some alternate kinds of social settings, some of the sex-risk differences are explainable or understandable in terms of the social circumstances that you grow up and live in.
In our culture, we grow up with some sense of what’s proper to be talked about, and when to ask for help and when not to ask for help. And although depression is not a synonym for weakness, there is some general view that if you were strong enough or tough enough, or more resilient, or more resourceful, you wouldn’t need to ask for help. And so, there is some tendency for people to suffer in silence. They have certain perspectives about going to the psychologist or going to a therapist or going to a psychiatrist, or even going to a primary care physician to talk about having depression. You just hope it will go away. And often, initial episodes of depression can be relatively short-lived and they do go away. So you don’t seek help. But then, sadly, if your depression doesn’t go away, it begins to have a life of its own.
And so, one thing that caring others can do if they see a loved struggling or in trouble is talk with them about it. And if it sounds like it’s starting to get in the way of their life—if it’s affecting their parenting, or if it’s affecting their workplace performance—encourage them to get some help.
Transcript edited for clarity.