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The overlap between substance problems and mental concerns, such as mood and behavior disorders, is large. If you have one, you’re more likely to find yourself with the other also.
For example:
- People with depression or anxiety are roughly twice as likely to have some kind of drug use disorder.1
- Research has found that more than 40 percent of people with bipolar disorder will have a substance use disorder during their lives.2
- The converse is also true. Among those who are seeking help for a substance use disorder, as many as 50 to 75 percent will also have anxiety, depression, or some other mental health issue.3
And here’s another common condition that’s also associated with a significantly increased risk of illicit drug use: ADHD. The relationship is quite high, and it begins in adolescence and continues into adulthood.
A 2011 study that followed kids and teens for 10 years found that those who were diagnosed with ADHD were 47 percent more likely to have a substance use disorder later in life than their peers without ADHD.4
So which condition causes the other?
This question arises in my psychiatric practice regularly. In all likelihood, some causation is traveling in both directions. Drug use—especially during adolescence—increases the chances of various forms of mental illness. Given that drugs can harm normal brain development, the drug use likely causes mental illness to arise in people who were already vulnerable to developing it.1 On the other hand, some people with a mental health issue may use drugs to self-medicate symptoms.
In any particular person, discovering which caused which is often impossible. Knowing the order in which these problems became apparent can be informative. But it’s not enough to lead us to state with certainty that one caused the other, because we usually can’t know if the second problem would have arisen anyway.
Reassuring findings about ADHD meds
This leads us to an important question about ADHD that concerns many parents. I have heard more than a few folks say something to the effect of: “Wait … psychiatrists and other doctors are putting kids with ADHD on stimulant drugs, which have enough kick that some people use them recreationally. Isn’t it possible that ADHD medications themselves put kids at higher risk of developing substance problems?
That’s a valid concern, given that nearly 3 million kids and teens were being treated with medication for ADHD in 2007.5 However, although some might worry that treating ADHD symptoms with psychostimulant medications would result in later illicit drug use, a number of studies over the years have concluded that there seems to be “no compelling evidence that stimulant treatment of children with ADHD leads to an increased risk for substance experimentation, use, dependence, or abuse by adulthood.”6
It’s even possible that treating ADHD with medications helps protect kids from later drug use. One 2008 study followed 114 children with ADHD for five years, until they were 16 years old on average. Ninety-four of them had been treated with stimulant medications. The researchers found no increased risk of substance use disorders linked to treatment with stimulant medications. In fact, they found that kids who took these medications were 73 percent less likely to have a substance use disorder.7
Thus, although it might make intuitive sense to be concerned that treating ADHD with stimulants is setting the child up for trouble with drugs down the line, research does not bear that out and, in fact, it suggests the opposite.
The best advice for someone with either a substance use problem or mental health disorder is to remain vigilant for the emergence of the other type of problem. Their interrelationship is complex and still being sorted out – and it’s a good idea to tell any doctor who’s treating you if you have either (or both) of these issues.
SOURCES
1. National Institute on Drug Abuse. (2010). Comorbidity: Addiction and Other Mental Illnesses. Retrieved from http://drugabuse.gov/PDF/RRComorbidity.pdf
2. Merikangas, K.R., Akiskal, H.S., Angst, J., Greenberg, P.E., Hirschfeld, R.M., Petukhova, M., & Kessler, R.C. (2007). Lifetime and 12-month prevalence of bipolar spectrum disorder in the National Comorbidity Survey replication. Archives of General Psychiatry, 64(5), 543-552.
3. Hazelden Foundation. Frequently Asked Questions About Co-occurring Disorders. Retrieved from http://www.bhevolution.org/public/overview_faqs.page
4. Wilens, T.E., Martelon, M., Joshi, G., Bateman, C., Fried, R., Petty, C., & Biederman, J. (2011). Does ADHD predict substance-use disorders? A 10-year follow-up study of young adults with ADHD. Journal of the American Academy of Child and Adolescent Psychiatry, 50(6), 545-553.
5. Centers for Disease Control and Prevention. (2010). Attention-Deficit/Hyperactivity Disorder (ADHD): Data & Statistics. (2010). Retrieved from http://www.cdc.gov/ncbddd/adhd/data.html
6. Barkley, R.A., Fischer, M., Smallish, L., Fletcher, K. (2003). Does the treatment of attention-deficit/hyperactivity disorder with stimulants contribute to drug use/abuse? A 13-year prospective study, Pediatrics, 111(1), 97-109.
7. Wilens, T.E., Adamson, J., Monuteaux, M.C., Faraone, S.V., Schillinger, M., Westerberg, D., & Biederman, J. (2008). Effect of prior stimulant treatment for attention-deficit/hyperactivity disorder on subsequent risk for cigarette smoking and alcohol and drug use disorders in adolescents, Archives of Pediatrics & Adolescent Medicine, 162(10), 916-921.
