When Bipolar and ADHD Overlap: Diagnosis

Distracted, hyperactive, irritable, impulsive. Wait a minute, is this a list of DSM symptoms for ADHD or hypomania? How about we find out? Welcome to the Carlite Psychiatry Podcast, keeping psychiatry on a since 2003. I'm Chris Akin, the Editor-in-Chief of the Carlite Psychiatry Report. And I'm Kelly Newsom, a psychiatric NP and a dedicated reader of every issue. Your patient is a 24-year-old woman with bipolar 2, who recently came out of a mixed episode. Although her mood symptoms have cleared, she is still easily distracted, has difficulty organising her work and often forgets important tasks. She's read about ADHD online and asks if she can have a stimulant to help her focus. ADHD and hypomania share many symptoms in common, distraction, hyperactivity, impulsivity, irritability, and excessive talking. So how do you tell them apart? The usual advice is that the symptoms are episodic and bipolar disorder and continuous in ADHD. And while that makes great for a theoretical construct, it's a little harder to apply in practice. It's not always clear-cut when episodes of bipolar disorder begin and end. Cognitive problems are common in bipolar, even when the mood problems go away. And moody or affective temperaments are common in ADHD. And these can look a lot like bipolar. But the stakes are high here because stimulants are used as the animal model for mania. So we don't want to give them out on a whim. So come along with us on the steep dive and by the end of it, you'll have a much better idea of what to do when patients present with symptoms of bipolar and ADHD. There are four possibilities in these cases. They either have bipolar or ADHD or both, or they could have none of the above. ADHD and bipolar disorder can occur together and they do so in 10 to 20% of bipolar patients. But remember that ADHD is a neurodevelopmental disorder that doesn't always continue in adulthood. So if we're looking at adult bipolar, only half of these cases will continue to have ADHD, which brings the overlap down to 5 to 10%. On the other hand, bipolar disorder causes symptoms that mimic ADHD and the rates of false positives are high here. Studies find that if you just gave a screening instrument for ADHD to people with bipolar, up to half of them would screen positive, way more than 10% so we don't recommend that route to the diagnosis. And how do they know these are false positives? They follow it up with the structured interview for ADHD, which is a much better strategy. Even a classic ADHD symptom like excessive daydreaming can also be a sign of bipolar. In a large NIMH trial, trait daydreaming was one of the top three signs that differentiated unipolar depression from bipolar depression. These patients go about their daily routines while carrying on waltemitty-like fantasies in their head, as if they have multiple trains of thought at the same time. They may be having small talk of the checkout line while writing the great American novel in their head. There's a lot more overlap in the temperaments of ADHD and bipolar, but first a preview of the CME quiz for this episode. Or in CME for each episode through the link in the show notes. True or false? Effective temperaments are common in both ADHD and bipolar disorder. There are at least three reasons that you can get a false impression of ADHD in a bipolar patient, symptom overlap, temperamental differences, and cognitive problems that can build up as the bipolar illness becomes more chronic. Let's go through those three one by one. First is symptom overlap. All you have to do is read the criteria for mania, and you'll see it lists things like irritable, distracted, hyperactive, overly-talkative, impulsive, which are also common symptoms of ADHD. Now, in mania those symptoms are much more intense, but during hypomania they might look just like ADHD. The textbooks tell us that the difference is clear. If the symptoms are episodic and resolve with time, then it's bipolar. If the symptoms are steady throughout the lifespan, it's ADHD. But the second reason for false impressions of ADHD is going to make a mess of that clean distinction, and that is temperament. By polar it turns out is not just an episodic illness. For many people the manic-depressive symptoms bleed into their temperament, and those temperamental differences cause cognitive problems that can look just like ADHD. The problem here is that temperament and ADHD both follow the same time course. They are traits that are constant throughout life and can be traced back to the preschool days. Temperament affects a person's emotions, behavior, and thinking. So when a patient says they are always distracted, daydreaming, and disorganized, it's hard to know if that is ADHD or one of the affective temperaments. There are four affective temperaments that are seen more often in patients with bipolar disorder, as well as in their relatives. And I'll describe them here along with the mood that they match up with because each one is thought to match up with a particular bipolar mood. There's dysthymic, which is a temperamental depression, hyperthymic, a hypomanic temperament, irritable, which matches with a mixed state where depression and hypomania overlap. And finally, psychothymic, which is like a temperamental form of ultra-rapid cycling. Around 50% of people with bipolar disorder have one of these temperaments. Now, savvy listeners might be thinking, "Yeah, I get it that the hyperthymic temperament can make people distracted, impulsive, and restless." And psychothymic can make people disorganized, inconsistent, and scatter their priorities. But don't these temperaments come with a lot of mood symptoms? And wouldn't that make it easy to tell them apart from ADHD? No. Pay attention because this is where the overlap gets very confusing. I just said that about 50% of people with bipolar disorder have one of those affective temperaments. Well, 40% of adults with ADHD also have an affective temperament. Adults with ADHD, even more than children with ADHD, are more likely to endorse symptoms of psychothymic and irritable temperaments, but also of hyperthymic and dysthymic ones. Try it out for yourself. You can take the temperament test on my website, chrisacanmd.com/tempsa. That's T-E-M-P-S-A. The overlap between affective temperaments and adult ADHD is so striking that it has led some psychiatrists like Nasser Gammie to suggest that most cases of adult ADHD are really due to these moody temperaments. To drive this point home, Dr. Gammie and colleagues published a paper last year where they looked at long-term outcomes in patients with psychothymia who were prescribed amphetamines for ADHD at the Tufts mood clinic. The meds helped their cognition a little about 24% better, but for about one in three of those patients, their mood worsened over time on the amphetamines, much higher than in a comparison group. The overlap of temperament and ADHD doesn't stop here. Temperamental differences are part of human nature. They're not just part of bipolar. Some people are more focused and some tend to wander. Some plan ahead and others live in the moment. ADHD is supposed to be an inborn disorder of hyperactivity, impulsivity, and inattention. But if somebody has a cognitive style that doesn't fit well with the demands of their worker school, it can look a lot like ADHD. Even though it's just a difference in the bell curve of their cognitive style. In practice, it's very difficult to tease apart temperamental differences from true ADHD, whether the person has bipolar disorder or not. It's tempting to say that if the moody features of the temperament are more prominent than normal, and it's probably an affective temperament, or if they have more family history of bipolar disorder, then it's probably an affective temperament and not ADHD. But I've been fooled many times. I have seen people that I was convinced have psychothymic disorder, and I treated them with hemotorgene with no difference only to switch to methylphenidate, and have it change their lives. And I've seen it go the other way as well. So I don't have great guidance for you on how to tease apart this diagnosis, and what to do about it, other than to recognize that these moody temperaments are much more common in people with bipolar disorder, and they might lead to a false positive of ADHD. (gentle music) - So far, we've covered two reasons for false positives. The overlap of manic and ADHD symptoms, and the continuation of those symptoms at a temperamental level, especially is psychothymic or hypothymic temperaments. The final reason for a false positive is that cognitive problems are common in bipolar disorder, and for 30 to 60% of people with bipolar, those cognitive symptoms continue, even after their mood episodes have resolved. Here, there is a way to distinguish it from ADHD. In true ADHD, the cognitive symptoms start in early life. They may get better or stay the same in adulthood, but they don't get worse with age. In bipolar, the cognitive symptoms start after the mood problems, and they get worse with time. In fact, the top predictor of cognitive symptoms in bipolar is the number of past mood episodes. - The time courses here might differ with an early onset in ADHD, and a later onset of cognitive problems in bipolar disorder, but the cognitive symptoms themselves have a lot in common. There are very few differences, though, and those might tip you off that they are due to bipolar disorder. Here's what to look for. Unlike an ADHD, cognitive problems caused by bipolar disorder are more marked by memory impairment and mental slowing. So, get that. If your patient has a lot of memory problems and slowing down of their thoughts, that's more likely due to bipolar than ADHD. People with pure bipolar usually lack the restless frenetic energy of all that hyper-distracted thoughts that you see in ADHD. (upbeat music) - Now that you know some of the ways these diagnosis get tangled up, here's a five-step guide to untangle them in practice. When an adult with bipolar disorder presents with ADHD like symptoms, use the following steps to figure out the cause. One, wait until their mood episodes have resolved for four to six months before assessing for ADHD. Two, assess for childhood onset of ADHD before age 12 to rule out cognitive deficits from the progression of bipolar disorder. Three, rule out other causes of cognitive problems like substance abuse, sleep deprivation, traumatic brain injury, and medical illnesses. Example, sleep apnea, hypothyroidism, cerebral vascular disease, and a recent infection. Four, screen for effective temperaments with the temps-A scale. Five, carefully assess for ADHD with the DSM-5 criteria, preferably using a structured interview. A structured interview for ADHD is gonna help filter out some of those look-like symptoms that confuse the picture. It sounds cumbersome, but it's not. These instruments simply translate the DSM criteria, which you should be using anyway, into questions like, do you often have difficulty sustaining your attention during tasks? And how was that in your childhood? The Diva-5 is a good option as a structured interview for ADHD. You can find it online at www.divacenter.eu. Another one that covers ADHD along with a wider array of psychiatric disorders is the Mini-7, which you can find at harmresearch.org. A structured interview for ADHD and for other mental illnesses is gonna do a pretty good job of ruling out other causes of ADHD symptoms, but there is one problem that remains. What if your patient meets full DSM-5 criteria for ADHD? But they also have a prominent affective temperament, so you're not sure if the cognitive problems are due to their temperament, and it's really a mood disorder, or if they do the ADHD and the temperament is just a secondary thing. This is where things really get difficult. Nassir Gammie has written a lot about this overlap, and to sum up his position, he views temperament affective temperament as primary, and he thinks that most of these cases in adults are due to the affective temperaments and not to ADHD. I'm not gonna pretend to have an Occam's razor here to split the two apart. So I think in these cases, it's best to just acknowledge the uncertainty and proceed gingerly with treatment, starting with medications for ADHD that have a low risk of worsening mood or causing mania. Those would be like Plondidine and Guadphocene, and we're gonna get more into that in our next episode where we talk about how to treat ADHD in bipolar patients. (gentle piano music) Let's recap this episode. Cognitive symptoms are common in bipolar disorder, even after the mood episodes have resolved. Common causes include cognitive deficits from the progression of mood episodes. Effective temperament like cyclothymic or hypothymic, or a genuine comorbidity with ADHD. A detailed history in some structured testing can clarify this cause. Now you know how to diagnose ADHD in bipolar. Next week we'll teach you how to treat it. Meanwhile, check out our new issue on our website for articles on tapering psych meds, anti-sacotics and depression, and updates on by-bands, lithium, treatment-resistant depression, and schizophrenia. Get $30 off your first year subscription with a promo code podcast. Thank you for helping us stay free of commercial support. (gentle music)