This superb summary of ADHD is likely to be of interest to several different types of reader. First, the physician who wants a brief (the entire book, including index, is 125 pages) overview; second, the therapist whose patients have ADHD and wants to learn more about it; third, the parent who wonders if their child has ADHD, and whether they should treat it, and how; fourth, the curious layperson.
Dr. McGough, a professor of psychiatry at UCLA, and one of the top researchers in the ADHD field, is a forceful lecturer, and his book is also pithy and powerful. Every sentence counts; there is not a wasted word. The person who likes to highlight the text will often be confronted with entire pages of yellow.
His book, the first in a new series, the “Oxford American Psychiatric Library”, by Oxford University Press (other volumes are bipolar disorder by Stephen Strawkowski, MD and Schizophrenia, by Stephen Marder, MD) captures the state of the art of ADHD knowledge and treatment in 2014.
Let’s take a brief tour through this book.
In the Introduction, Dr. McGough notes that ADHD “is a frequently occurring, brain-based, neurodevelopmental disorder with substantial negative consequences for individual and public health. Once viewed as a childhood condition, , it is now recognized that a majority of cases persist throughout adolescence and adulthood.”
“The high community prevalence of ADHD suggests that there are affected patients in virtually every clinical practice in every medical specialty. Nevertheless, comprehensive education about ADHD is largely limited to specialized programs in child and adolescent psychiatry and behavioral pediatrics.”
“MIsinformation about ADHD abounds. Some assert that ADHD is not real….that childhood inattention and hyperactivity are normal, the diagnosis is subjective….older student fake symptoms to obtain academic advantages….adults are similarly drug seeking….or that the condition represents a conspiracy by pharmaceutical companies and organized psychiatry to increase medication sales.”
“ADHD…is among the most scientifically validated psychiatric disorders”, with diagnostic reliability “on par with many conditions in general medicine”,and well demonstrated biological underpinnings….”the accumulated evidence base for its clinical management is of the strongest in mental health. Medications for ADHD have been used for over 70 years in millions of patients annually, creating an indisputable record of real-world safety and positive benefit….Treatment effect sizes are double those typically seen with more widely prescribed medications for depression and schizophrenia.”
Chapter 2, Historical Perspectives, reviews the history of ADHD (first mentioned in an 18th century medical text) and follows it through the various iterations of the DSM, including the DSM-5.
Chapter 3, Epidemiology and Burden, notes how common the condition is, with an estimated 5.3% worldwide mean. Male/female ratios, 9/1 in school age clinic samples, are 1/1 in adult clinic samples. This implies that boys are treated as children because they are more likely to disrupt the classroom, while quietly inattentive girls are ignored. The late Dennis Cantwell, MD, one of my best teachers, used to describe boys as having “garlic symptoms” (which bother the environment), while girls have “onion symptoms”, and suffer internally.
Chapter 3 also notes the extensive co-morbidity of ADHD, Mood disorders and anxiety disorders are quite common, and often the underlying ADHD is missed. Chapter 4 reviews etiology and neurobiology. Chapter 5 reviews diagnostic criteria, especially the different forms the criteria take in children and adults.
Chapter 6 reviews the various aspects of a thorough assessment. “ADHD is a clinical syndrome….ADHD is not diagnosed on the basis of any distinct neuropsychological profile. There is no scientific justification for claiming to diagnose ADHD on the basis of other laboratory studies, computerized tests of attention, electroencephalography (EEG), or other brain imaging methods.” A careful reading of this chapter could save a parent thousands of dollars, and spare a child needless radiation exposure.
Chapter 7 and 8 review Treatment Planning in Children and Adolescents, and in Adults.
Chapter 9 reviews basic pharmacology.Here are a few of the pearls strewn though its pages. “It is commonly stated that 70% of patients respond favorably to stimulants. In fact, approximately 70% respond favorably to the first stimulant prescribed, whether a methylphenidate or amphetamine. Of those who fail, an additional 70% respond favorably to the alternative class. As such, more that 90% of patient have satisfactory clinical improvement with stimulants, at least during acute treatment.”
Is my child/spouse/partner being overmedicated by their physician? Tables 9-2, 9-3, and 9-4 and the associated text show the reader how the meds are commonly used, ie what are the usual standards of care.
OK, so should I start my ADHD patients on amphetamine or methyphenidate? “Some patients respond preferentially to one or another stimulant class, but there is no method other than clinical trial and error to predict whether MPH or AMPH is the optimal choice.”
OK, so what is the difference between how methyphenidate and amphetamine work at the cellular level? “Both AMPH and MPH inhibit catecholamine reuptake into presynaptic neurons by blocking norepinephrine and dopamine transporters. AMPH further directly displaces norepinephrine and dopamine from presynaptic storage vesicles, and it inhibits monoamine oxidase and subsequent neurotransmitter breakdown.”
OK, so how do these drugs work at the level of brain circuits? This is fascinating, and a little complicated, and still being worked out, but here goes (pages 74-75): “Recent research suggests that ADHD treatment response is not a direct effect of increased catecholamine release, but that increased levels of norepinephrine and dopamine have indirect modulating effects on glutaminergic signaling in the the prefrontal cortex (PFC).”
PFC circuits regulate lots of stuff (attention, executive functioning, etc, etc). “One subset .. mediates active attention to “preferred” inputs or “signals”, while another subset mediates attention to “nonpreferred” inputs or noise.”
so “ADHD treatment can be viewed as a rebalancing of “signal” to “noise” ratios….Ideally, individuals should appropriately focus on important tasks (signal), while retaining some awareness of background activity (noise) and the ability to shift attention flexibly when required. Optimal balancing of signal to noise ratios in the PFC is dependent on a narrow range of catecholaminergic activity. If catecholamine levels are excessively elevated, perhaps from too high medication doses or stress, PFC networks collapse with concomitant deteriorations in cognitive or motor control. Dopamine increases that might be useful for tasks requiring highly focused attention could also cause problems with overfocus, cognitive rigidity, and a loss of personality and spontaneity.”
This is, in my opinion, a brilliant and succinct summary of a very complicated area, and it suggests what a delicate touch is required in adjusting a patient’s medication.
Chapter 10 is clinical medication management. Dr McGough has developed a method (which in my notes I label the McGough titration) to quickly (within 2 weeks) and efficiently (with one prescription) answer 2 questions: is this medication helpful or harmful to my patient, and what is the optimal dosage ? (pages 81-83, and table 10-1). When to use combination pharmacotherapy, and how to handle various common side effects are also discussed.
My psychiatrist wants to see me every month to give me refills. Is this really necessary? (see page 82)
Patients are often dealt more than one diagnostic card, and chapter 11 shows how to deal when a patient has comorbid diagnoses.
Chapter 12 reviews medication controversies Do ADHD meds stunt growth or cause sudden death? Should one get an EKG before starting a stimulant? What if the patient is using alcohol or marijuana? Do ADHD meds cause birth defects? Do patients fake symptoms to get stimulants? Do ADHD meds stop working?
Chapter 13, Complementary and Alternative Medicine Therapies, covers the evidence base, and the quality of the research, for restriction/elimination diets, dietary supplements, neuropsychological treatments, and mind-body therapies. Careful reading of this chapter could help parents avoid wasting a lot of money on treatments with scant evidence to support their efficacy. The treatments with the strongest evidence base are the addition of essential fatty acids, and the removal of artificial colors.
This is a book that the practicing psychiatrist will want to read from cover to cover, and then read again. It may be of even more benefit to the parent or the adult patient.