In this CME article, learn more about the full continuum of presentations and variable trajectories typical of females with ADHD.
Premiere Date: July 20, 2023
Expiration Date: January 20, 2025
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The goal of this activity is to inform the reader of the full continuum of presentations and variable trajectories typical of females with ADHD and the factors that contribute to the misdiagnosis of females with underlying ADHD.
After engaging with the content of this CME activity, you should be better prepared to:
1. Increase diagnostic accuracy through greater familiarity with the full continuum of presentations and variable trajectories typical of females with ADHD.
2. Achieve earlier identification by utilizing more inclusive evaluations that assess the internalizing symptoms and functional impairments typical of females with ADHD.
3. Become better attuned to the factors that contribute to the misdiagnosis of females with underlying ADHD.
This accredited continuing education (CE) activity is intended for psychiatrists, psychologists, primary care physicians, physician assistants, nurse practitioners, and other health care professionals who seek to improve their care for patients with mental health disorders.
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In the case of attention-deficit/hyperactivity disorder (ADHD), diagnostic criteria are presumed to pertain to girls and women as accurately as they do to boys and men. The lower prevalence of girls has been understood as evidence that more boys than girls have ADHD. However, population studies reveal that men and women are now almost as likely to be diagnosed,1 suggesting that the lower prevalence of girls may not simply be attributable to a sex difference.
Despite similar symptomatology, evidence-based sex and gender differences (in prevalence, presentation, symptom expression, trajectory, and impairment) are emerging. This literature on girls and women with ADHD is steeped in controversy and inconsistent findings, highlighting the dearth of research exploring the experiences of females with ADHD. The need is urgent for a reconceptualization that acknowledges females—the sex and gender differences that are associated with unfamiliar presentations, complex trajectories, hormonal mediation, cumulative impairments, and an unanticipated severity of outcomes. The underdiagnosis of girls has unintentionally allowed these women to live without an understanding of why their brains are in conflict.
ADHD is more commonly diagnosed in boys than it is in girls, with greater prevalence noted in clinical versus population samples. The current child prevalence ratio of about 2:1 in population samples indicates that girls are half as likely as boys to receive this diagnosis.2 There is significant support for the theory that girls are underrecognized, understudied, and underdiagnosed. Predominantly inattentive symptoms, internalizing symptoms, comorbidities, masking tendencies, and hormonal mediation combine to create complex and unfamiliar presentations. In addition, referrals, sampling, assessment measures, and diagnostic criteria are skewed due to gender bias. Taken together, girls face multiple obstacles to diagnosis that are not shared by boys, resulting in many girls being overlooked, misdiagnosed, or diagnosed late.
For decades, the criteria’s anachronistic cutoff age of 7 years prevented most prepubertal inattentive girls from diagnosis. In fact, the vast discrepancies in prevalence prompted a keynote speaker in the early 1990s to deem girls “ADD wannabees.” Increasing the criterion to age 12 years in 2013 allowed more girls to receive delayed diagnoses,3 with a dramatic shift in prevalence. Nonetheless, many girls’ symptoms would not reach the diagnostic threshold until later in adolescence, resulting in many boys benefiting from intervention about 10 years earlier than did girls.
Since men and women are now being diagnosed at similar rates, the disparity between diagnosed girls and women suggests that many girls overlooked in childhood are diagnosed by adulthood. Hence, prevalence estimates reflect the underdiagnosis of girls but not necessarily the underdiagnosis of females in general.4
Symptomatology and Persistence
Until 2013, ADHD was classified in the Disruptive Behavior Disorders of Childhood category in the DSM-IV with hyperactivity as the hallmark, reflecting entrenched historical precedents. It was reclassified under Neurodevelopmental Disorders in the DSM-5, with observable externalizing behaviors still dominating over less overt inattentive symptoms. Presenting without externalizing behaviors and masking gender atypical differences, girls are frequently overlooked, and that lack of recognition has played a central role in their underdiagnosis. Klefsjo et al found that girls were more frequently referred for emotional symptoms than ADHD symptoms and were older at diagnosis than were boys.5 Subtypes, once considered discrete entities, are now conceptualized as dimensional variables, acknowledging that presentations change across the lifespan.
In both sexes, developmental trajectories begin with primarily hyperactive symptoms in preschoolers that have been associated with an increased risk of depression by adolescence, especially in girls.6 Boys are more likely than girls to develop externalizing symptoms such as hyperactivity, impulsivity, defiance, and rule-breaking in early childhood. Inattentive symptoms such as being distractible, disorganized, unmotivated, and forgetful tend to emerge during the elementary school years in members of each sex and remain relatively stable over time.
Although the majority of girls are more likely to present with predominantly inattentive symptoms, they also experience hyperactivity, manifesting as restlessness and fine-motor fidgeting like cuticle tearing and nail biting. Impulsive girls can be hyperverbal and charismatic, but they are also more likely than their neurotypical peers to exhibit covert externalizing behaviors like manipulation, exclusion, and lying. These girls are also more likely to be risk-takers, and they may prefer the company of boys, who may be more comfortable with their gender-atypical behaviors.
Hormonal fluctuations at puberty exacerbate symptoms and destabilize functioning in both sexes. The majority of impulsive boys maintain a relatively steady trajectory throughout high school, with hyperactivity diminishing throughout adolescence.7 In comparison, adolescent girls are more likely to struggle socially and experience dysregulated emotions, sleep, and diet in response to a barrage of mood-based comorbid internalizing disorders.
Since the majority of cases persist into adulthood, women experience complex and unpredictable trajectories reflecting variable combinations of ADHD symptoms, mood-based internalizing symptoms, and other comorbid impairments.1 Such disparate sex-based predispositions to developmental vulnerability suggest that lifetime persistence may follow a more state-dependent course in females; this contrasts with the trait-based course based on male trajectories, which has been assumed to describe the course of the disorder.8
The majority of girls with ADHD will develop at least 1 comorbidity by early adulthood; however, inattentive girls’ presentations pose particular diagnostic challenges, with subtle prepubertal symptoms segueing into more observable internalizing mood and anxiety comorbidities. Anxiety may manifest as obsessiveness, phobias, separation anxiety, social anxiety, and generalized anxiety disorder. Clinicians unfamiliar with these common internalizing comorbidities may deem these symptoms primary diagnoses rather than secondary sequelae of ADHD.5
In fact, Skogli et al found that comorbid anxiety symptoms could more reliably identify ADHD in girls than could the diagnostic symptoms themselves.2 Compared with males, undiagnosed females are at particularly high risk for depressive symptoms escalating into major depressive disorder, which is associated with earlier onset, greater episode duration, and more severe impairments often accompanied by some manifestation of self-harm.9 Observable comorbidities affect members of each sex (Table 1); however, their overt symptoms can overshadow subtle symptoms and increase the likelihood of misidentification as primary diagnoses. Members of each sex may develop personality disorders, although women—especially those with trauma histories—are more likely to develop borderline personality disorder with intense symptoms that can obscure underlying ADHD.
Peer acceptance is a powerful determinant of self-worth for females. However, girls with ADHD struggle socially more than do boys with ADHD or neurotypical girls. Low self-esteem and developmental immaturity often thwart their participation in the intimate ecosystem of girls’ socialization. Girls with ADHD may withdraw, intimidated by expectations for rapid verbal interplay and empathic engagement. Girls experience greater emotional dysregulation and rejection sensitivity than do boys, increasing their likelihood of being labeled “drama queens” by exasperated peers. Impulsive girls are more likely to evoke peer rejection for domineering or manipulative behaviors, which is now easily weaponized as cyberbullying on social media.10 In contrast, boys’ socialization requires less emotional intimacy, offering boys with ADHD routes to acceptance via parallel activities like competitive video games or sports.
Inattentive girls with social anxiety are more likely to be ignored or victimized by peers, whereas impulsive girls with externalizing symptoms tend to bully, exclude, and torment more passive girls, evoking peer rejection.10 Compared with boys, girls demonstrate less social competence, experience more negative peer interactions, and have fewer and less satisfying friendships, all of which contribute to the elevated stress levels reported by adolescent girls relative to their neurotypical peers.11
Even preadolescent girls discover that sexuality can facilitate peer acceptance, and girls with ADHD may unwittingly participate in online and in-person sexual exploitation. Desperate to belong and ignorant of the risks, girls with ADHD comply with demands that they are ill-equipped to handle and ashamed to disclose. They are more likely to become sexually active earlier than are their neurotypical peers and to have more partners, shorter relationships, and less contraceptive use, resulting in increased risks for sexually transmitted infections and a 6-times higher risk of unplanned pregnancies.12 They may also seek to bond over other high-risk behaviors involving nicotine, drugs, alcohol, truancy, vandalism, or theft.
Societal Dynamics and Stigma
Society still supports the traditional feminine obligations to comply, accommodate, organize, and nurture others before themselves. With increased responsibilities and less scaffolding, young women with ADHD strive to conform to these anachronistic role expectations and judge themselves harshly compared to their peers. To mask gender-atypical behaviors, they rely on compensatory tools like intellect, humor, hypervigilance, self-censoring, obsessiveness, and perfectionism.13
To avoid social sanctions and moral judgements, many attempt to obscure their differences, albeit at a high emotional cost. They invest significant time and energy in cultivating a flawless facade proffering the illusion of neurotypical functioning. Although dreading discovery as impostors, many females prioritize the reflected appraisal of others over the realities of their functional challenges.14 Ironically, their hidden situation is no less damaging. They present without symptoms to clinicians, and their rigid compensations further decrease the likelihood of diagnosis. In socializing with peers, despite masking, they hover near the periphery of social interactions, still anticipating criticism or rejection.
After repeated social failures, some demoralized females find their vulnerabilities so intolerable as to seek relief through a variety of self-harming behaviors. Although adolescent girls are, in general, at higher risk than boys for self-harm, impulsive adolescent girls with ADHD are at the highest risk of the most severe self-harm, including suicidal ideation and attempts; their rates of these behaviors are significantly higher than noted for their neurotypical peers, boys with ADHD, and girls with predominantly inattentive ADHD.
The impact of gender role expectations has received negligible attention, as it may have little salience for males with ADHD. However, for some adolescent girls with ADHD, social and academic failures combined with antiquated societal guidelines may be perceived as moral indictments that undermine self-esteem and increase shame.15
Across central nervous system disorders, a developmental pattern of gender-specific vulnerability is well-documented. Boys are more vulnerable to the development of behavioral disorders in early childhood, whereas girls are more vulnerable to the development of emotional disorders after puberty, when symptoms surge in response to the release of estrogen.
An emerging body of literature is exploring the ways in which these differences may be associated with the variability of the female ADHD experience. There is now evidence that ADHD symptom severity varies in response to hormonal fluctuations.8 Girls enjoy enhanced cognition, mood, motivation, verbal memory, and sleep when estrogen and corresponding dopamine levels are high. However, during low-estrogen/low-dopamine states, girls are likely to experience exacerbated ADHD symptoms and comorbid internalizing symptoms, including premenstrual mood symptoms. This cumulative symptom burden can destabilize even the highest-functioning girls.
However, the spike in symptom severity amplifies visibility, allowing many girls to be identified and diagnosed later in adolescence.8 The impact of hormonal fluctuations on the variability of presentations of girls can be dramatic. A premenstrual girl with ADHD presenting to a clinician as insecure, anxious, and despondent can appear confident, effective, and hopeful a week later, after menstruation commences. Hence, an awareness of hormone levels, whether related to menstrual phase or an external source, will enhance diagnostic accuracy.
Understanding that females with ADHD are vulnerable to cycling steroids is a game-changer, along with the crucial corollary that impulsive girls are particularly sensitive to the fluctuations; further, they may be especially reactive to depressive feelings in the low-estrogen state.16 Women with ADHD exhibit high rates of premenstrual syndrome, premenstrual dysphoric disorder, severe postpartum depression, and climacteric symptoms when compared with their neurotypical peers.17 Women now spend more than one-third of their lives in menopause; it is essential that clinicians recognize presentations of high-functioning, older women experiencing exacerbated climacteric and ADHD symptoms.1
Sex and Gender Bias
Psychiatric research on males is a longstanding methodological practice, as is the generalizing of those findings to females. ADHD research favors clinical samples that skew toward the most disruptive children. Comparing the behaviors of these boys to those of the few girls diagnosed due to similar disruptive behaviors, it is not surprising that minimal sex-specific symptom differences have been found between the 2 groups. According to this circular logic, the lack of sex differences may have indicated that further study of girls was unnecessary.
The selection bias extends to samples of adolescent girls diagnosed in childhood—a cohort of impulsive young girls identified early due to externalizing symptoms. Findings among these female participants again overlooked the experience of the majority of predominantly inattentive girls, whereas our knowledge of impulsive girls is ever more finely honed. Although criteria were modified in 1980 to permit diagnosis without hyperactivity, and despite the National Institutes of Health’s updated 2014 policy requiring inclusion of female participants and analyses by sex in clinical trials to maintain funding, compliance has been minimal.
Gender bias has perpetuated the generalization of findings based on predominantly male participants to all girls with ADHD, even though they are unrepresentative of both the majority of girls and the demographics of the population. Parents and teachers unwittingly contribute to girls’ underdiagnosis when they are more likely to refer boys based on scales designed to identify disruptive behaviors, even when the girls themselves endorse other ADHD symptoms. After decades of reconsideration, the DSM-5 reinforces the preeminence of its male-dominated criteria by dismissing the sex and gender differences literature with 2 sentences, reflecting a seemingly determined unawareness of female experiences and outcomes.
For members of both sexes, ADHD is associated with profound psychiatric, psychosocial, educational, vocational, and health-related problems, leading to extraordinary individual and societal costs. Still, females experience greater severity of impairments and comorbid disorders across most domains.
Females with ADHD have higher risks of eating disorders, sleep disorders, and tobacco addiction.18 They are at higher risk unplanned pregnancies than are their neurotypical peers.11 With greater pain sensitivity, they are more likely to experience somatic discomforts like headaches and stomach discomfort, to have disorders like migraines and asthma, and to have more tactile defensiveness. They are more likely to take prescription medications for anxiety and depression and to practice inconsistent health maintenance, which increases their risks for medical problems.8 They are also more likely to underachieve academically and/or vocationally (Table 2).
Females are more likely than males to have experienced early neglect and physical and/or sexual abuse, which predispose them to some of the most severe outcomes.19 Compared with their neurotypical peers, adolescent girls diagnosed in childhood are at high risk for experiencing physical violence in romantic relationships by early adulthood.20 They are also at high risk for problematic driving behaviors and criminal behaviors that can lead to incarceration when compared with their neurotypical peers.
Impulsive adolescents, especially those with externalizing behaviors and histories of adversity, are at alarmingly high lifetime risk of self-harm which, in turn, can increase their risk of suicide attempts.21 Although adults with ADHD have reduced estimated life expectancies, primarily due to accidents and risk-taking, women are at even higher risk than men.22 Perhaps this daunting catalog of impairments and outcomes will serve as a wakeup call, urging researchers and clinicians to unite in addressing the shocking number of self-harming females beset by unbearable shame, stigma, isolation, and despair.
Clinicians may be unaware that the majority of girls with ADHD still fall through gaps in the literature. Diagnostic accuracy depends upon familiarity with the widest continuum of ADHD presentations, since they represent a variety of developmental trajectories and associated risks. Until there are more studies reflecting the diversity of individuals with ADHD, some routine additions to standard evaluation techniques could provide valuable insights (Table 3).
This consideration of sex and gender differences in ADHD is not intended to be an overview of the female experience—but neither should it be an overview of the male experience. Bridging the abyss between the 2 knowledge bases is long overdue. The intent of this article is to increase awareness of the ways in which the experiences of girls and women with ADHD vary significantly from those of boys and men. It is also a consideration of how that lack of recognition has persisted and how the implications render many girls and women invisible.
This is 1 conceptualization of the research and clinical experience viewed through the lens of 33 years of working with this population. Despite inconsistent findings and controversies, this is a perspective shared by a rapidly growing cadre, although alternative conclusions can always be drawn from the same data.
Institutionalized gender bias, however unintended, has proven insidious and powerful. Clinicians have had minimal resources describing the majority of females with ADHD without externalizing disorders. As consumers of the existing research, clinicians should be circumspect in interpreting the findings. Studies based on male-dominated clinical samples that have minimal female representation and that use biased assessment scales and diagnostic criteria may not describe the majority of girls with predominantly inattentive ADHD.
To capture the greatest range of symptoms and their manifestations, we might consider a conceptual shift in our model. Instead of measuring observable externalizing behaviors, we might cast a wider net by assessing personal experiences of functional impairment. Both males and females experience functional impairments across the lifespan. Operationalizing emotional dysregulation, internalizing symptoms, and indications of trauma and self-harm in addition to behavioral criteria could provide a more comprehensive and inclusive scale and increase the likelihood of graduating from subthreshold status. Acknowledgment of the variability of trajectories, especially in females, warrants an awareness of hormonal mediation of symptom expression.
As the range and severity of outcomes mount, it is imperative that research explore why ADHD exacts a greater toll on the functioning of females than on males. It is urgent that research correct the historical neglect of half the population by demonstrating a commitment to greater female representation. The greatest risks for severe outcomes are gender- and sex-specific; we have a responsibility to explore the vulnerabilities that predispose females to struggle so much more than do males. These are basic yet powerful future directions, since more knowledge will absolutely increase diagnostic accuracy and permit the earlier identification enjoyed by many boys. The longer girls and women remain undiagnosed, the more likely they will attribute their compromised quality of life to their own character flaws, feeling no efficacy to stem the tide of the lengthening shadow of shame, self-blame, and demoralization.
Dr Littman is a clinical psychologist who has specialized in the diagnosis and treatment of neurodiverse disorders for more than 30 years. Described by the American Psychological Association as “a pioneer in the identification of gender differences in ADHD,” Dr Littman coauthored the book Understanding Girls With ADHD in 1999, with an updated edition published in 2015. Educated at Brown and Yale Universities, Long Island University’s doctoral program, and the Albert Einstein College of Medicine, her private practice just north of New York City focuses on high-IQ neurodiverse adults. Mr Wagenberg earned his graduate degree at Hunter College in New York, New York. He has been editing scientific papers for 15 years, with a special interest in ADHD.
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