What makes a person get bipolar disorder? Can you “catch” it? Why is it that it seems to run in families? And what makes some people more at risk for developing compared to others – even within the same family? And perhaps most importantly, what are some protective factors you can use to offset some of these risks?
This is a good moment to talk about causation and correlation. In discussing risk factors for bipolar disorder or any other disorder, you might hear a lot about correlations: x and y seem to co-occur at a particular frequency. Does that mean x causes y or that y causes x? Definitely not, but it does mean that if one is present, you have an increased chance of the other also being present. Sometimes, a correlation does indicate causation, but correlations that have other causes (for example two things happen at the same time but both are caused by a third factor) are much more common. Substance abuse and bipolar disorder are correlated in this way: if you have been diagnosed with one, it increased the odds that you may be diagnosed with the other, but that isn’t because drinking causes bipolar disorder or that bipolar disorder causes alcoholism. What seems most likely in this case is that a third factor – a particular genetic trait – causes both. Remember, though, if there is, for example, a 30% chance that you will be diagnosed with bipolar disorder based upon a correlation that you’ve discovered, that means that there is a 70% chance that you will not develop the disease.
Risk Factors for Developing Bipolar Disorder
So what are some of these correlations with regard to bipolar disorder? First and by far the most statistically potent correlation is that if any member of your family (blood relation) has been diagnosed with bipolar disorder, your chances of also being diagnosed increase. This of course brings up the whole “nature versus nurture” debate: is the likelihood increased due to genetic or other “endogenous” (meaning physical, or internal) factors or is the likelihood of developing bipolar disorder increased because of what being exposed to bipolar disorder does to children?
There is good evidence cited in several studies to indicate that genetic factors really do predispose some people to bipolar disorder and that these genetic factors are passed on form generation to generation. However, there are also studies that show that childhood exposure to inconsistent, chaotic households in which boundaries are transgressed, violence is witnessed, or abuse is experienced (all possibilities in a home where a parent is suffering from bipolar disorder) also increase the likelihood of being diagnosed with any mental illness later in life. The best answer, it seems at this point, is that via both the nature and nurture routes the presence of a blood relative with bipolar disorder in your family tree will increase the chances of you being diagnosed with bipolar disorder.
Having a substance abuse diagnosis (or meeting diagnostic criteria whether or not you’ve ever been formally diagnosed) will also increase the chances that you will be diagnosed with bipolar disorder. Again, drinking or using drugs does not cause bipolar disorder, and if you do not have bipolar, no amount of drinking or drugging will make you “catch” it, but statistically, if you have one, then you are much more likely to also have the other.
Age plays a role. Bipolar disorder is also quite commonly diagnosed in people in their twenties. While children as young as four or five years old have been diagnosed, and occasionally people first exhibit symptoms later in life, most commonly the onset of bipolar occurs in the decade of your twenties. In addition, there is a relationship between age at the time of your first manic episode and likelihood of being diagnosed with bipolar disorder, as it is possible that a manic episode could be an isolated single event.
Gender does not seem to be a risk factor, as both men and women are diagnosed in fairly equal numbers. However, the rate of comorbidity of substance abuse and bipolar disorder is higher among males. Women are more frequently diagnosed with two specific subtypes of bipolar disorder: cyclothymia and rapid cycling.
Finally, having experienced a serious trauma seems to be correlated with being diagnosed bipolar. This may sound odd, as intuitively you might think that trauma would more likely to lead to a diagnosis of post traumatic stress disorder, but the correlation is there: intense stressful life experiences can lead to manic episodes or profound depression. This may be in part due to the genetics or structural issues in the brain that predispose a person to develop mood rather than trauma symptoms.
Remember that risk factors are not causes. What causes bipolar disorder is not known, and several theories compete for prominence in the literature. But the statistical correlations noted above indicate probabilities or chances, not predictions. The best way to decrease the impact of any risk factors you may have is to practice good mental “hygiene” every day: own your emotions and express them in healthy and productive ways. Spend time doing things that make you laugh and deepen your meaningful connections with your loved ones. Seek help when stressed, and be honest about what you experience. You might not be able to prevent bipolar disorder but you can certainly prevent the serious negative impact it has on your life if you take responsibility for doing so.