With prevalence rates as high as 50%-70%, substance abuse is highly prevalent in patients diagnosed with bipolar disorder. [1,2] As such, bipolar disorder and substance use disorders are often considered to be comorbid with the primary or leading diagnosis, on the basis of the patient’s ability to recall whether emotional lability pre- or postdated their use of substances. Because bipolar disorder and substance-induced mood disorders can acutely present in an identical manner; differentiating between the 2 can be very difficult, if not impossible, when mood lability is manifested. [3-5]
As a medical expert for the Social Security Administration for over 25 years, I have had the privilege of reviewing thousands of medical records with the directive to determine whether substance abuse is a material factor leading to mood lability when another axis I diagnosis has also been made.
What I have learned over the years has firmly changed my thinking on the determination of the impact of substance use disorders on mood lability. I have come to appreciate that there is little to no value relying on a patient’s recollection of when their emotional lability began, because memories falter and substance abusers invariably lie about their history of substance abuse. The diagnosis of a substance-induced mood disorder — drugpolar disorder, for short — should always be considered in patients with mood lability because it may be the primary, and possibly the only, true diagnosis.
–Nathan R. Strahl, MD, PhD, Medscape.com