Julia J. Rucklidge

Neuropsychological profiles of adolescents with ADHD: effects of reading difficulties and gender

BACKGROUND Executive function, particularly behavioral inhibition, has been implicated as a core deficit specific to Attention-Deficit/Hyperactivity Disorder (ADHD) whereas rapid naming has been implicated as a core deficit specific to reading disabilities (RD). Females may be less impaired in executive function although adolescent females with ADHD have yet to be studied. METHOD Neuropsychological profiles of four adolescent groups aged 13-16 with equal female representation were investigated: 35 ADHD, 12 RD, 24 ADHD+RD, and 37 normal controls. A semi-structured interview (K-SADS-PL), the Conners Rating Scales and the Ontario Child Health Study Scales were used to diagnose ADHD. RD was defined as a standard score below 90 on at least one of the following: Reading or Spelling of the WRAT3 or Word Attack or Word Identification of the WRMT-R. The WISC-III, Rapid Automatized Naming, Stroop and Stop tasks were used as measures of cognitive and executive function. RESULTS The two ADHD groups (ADHD, ADHD+RD) showed deficits in processing speed, naming of objects, poor behavioral inhibition and greater variability in reaction times whereas the two RD groups (RD, RD+ADHD) showed verbal working memory deficits and slower verbal retrieval speed. Only the comorbid group was slower with naming of numbers and colors and had slower reaction times. Regression analyses indicated that incongruent color naming (Stroop) and variability in go reaction time were the best predictors of hyperactive/impulsive ADHD symptoms whereas variability in go reaction time and processing speed were the best predictors of inattentive ADHD symptoms. Speed of letter naming and verbal working memory accounted for the most variability in composite achievement scores. No gender differences were found on any of the cognitive tests. CONCLUSIONS This study challenges the importance of behavioral inhibition deficits in ADHD and that naming deficits are specific to RD. Further investigation into cognitive deficits in these groups is required.

Gender differences in attention-deficit/hyperactivity disorder.

Attention-deficit hyperactivity disorder (ADHD) is recognized to exist in males and females although the literature supports a higher prevalence in males. However, when girls are diagnosed with ADHD, they are more often diagnosed as predominantly inattentive than boys with ADHD. This article provides a review of gender differences noted across the lifespan. Males and females with ADHD are more similar than different, and generally ADHD profiles are not sex specific. Small gender differences have been found: adolescent girls with ADHD have lower self-efficacy and poorer coping strategies than adolescent boys with ADHD; rates of depression and anxiety may be higher, and physical aggression and other externalizing behaviors lower in girls and women with ADHD. Men with ADHD seem to be incarcerated more often than women with ADHD. However, many studies suffer from small sample sizes, referral biases, differences in diagnostic procedures, and possible rater influences. Treatments are reviewed and discussed with reference to the reported gender differences in functioning and the global deficits noted in all samples. The data available so far suggest that treatments are likely to be equally effective in males and females. However, referral bias is a problem, in that females with ADHD are less likely to be referred for treatment than males with ADHD. Future research should include equal representation of both sexes in samples such that sex by treatment analyses can be routinely conducted.

Psychiatric, psychosocial, and cognitive functioning of female adolescents with ADHD

OBJECTIVE To characterize the psychiatric, psychosocial, and cognitive functioning of female adolescents with attention-deficit/hyperactivity disorder (ADHD) in comparison with female controls and males with ADHD. Female controls were also compared with male controls to verify gender differences in a nonclinical sample. METHOD One hundred seven adolescents from Southern Ontario aged 13 to 16 were included: 24 females with ADHD, 35 males with ADHD, 28 control females, and 20 control males. All were assessed with semistructured interviews, questionnaires, and tests of achievement and intellectual functioning. RESULTS After controlling for parental education and estimated Full Scale IQ, females with ADHD were more impaired than control females in depression, anxiety, distress, teacher relationships, stress, attributional styles, and locus of control and on all cognitive and achievement measures. Females with ADHD were more impaired than males with ADHD in self-reported anxiety, distress, depression, locus of control, and vocabulary scores. These group differences were confirmed by higher ratings by parents and teachers in symptoms of psychopathology. Males with ADHD were more impaired in processing speed. Some gender differences (locus of control and vocabulary scores) were eliminated when controlling for ADHD severity. The absence of any differences between male and female controls indicates gender differences were specific to the clinical groups. CONCLUSION Females with ADHD are at high risk for more psychological impairment than both males with ADHD and control females. The identified psychosocial problems point to areas for intervention.

Time perception deficits in attention-deficit/ hyperactivity disorder and comorbid reading difficulties in child and adolescent samples.

BACKGROUND Our objective was to investigate time perception in Attention-Deficit/Hyperactivity Disorder (ADHD) with and without comorbid reading difficulties (RD) in child and adolescent participants. METHOD In study 1, 50 children with ADHD (31 ADHD, 19 ADHD+RD) and age-matched healthy controls (n = 50) completed three psychophysical tasks: duration discrimination (target duration of 400 ms versus a foil duration), frequency discrimination (a control condition to evaluate general perceptual ability), and a duration estimation task using the method of reproduction for intervals of 400 ms, 2000 ms, and 6000 ms. Study 2 used the same tasks with an adolescent sample (35 ADHD, 24 ADHD+RD, 39 controls). RESULTS In both studies, children and adolescents with ADHD and ADHD+RD displayed some impairments in duration discrimination and the precision with which they reproduced the intervals on the estimation task, particularly the shorter 400 ms interval. The most severe impairments tended to occur in the comorbid ADHD+RD group. No impairments were found on the frequency discrimination task. ADHD participants also displayed significant intra-individual variability in their performance on the estimation task. Finally, short-term and working memory, estimated full-scale IQ, and teacher report of hyperactivity/impulsivity were found to differentially predict performance on the time perception measures in the adolescent clinical sample. CONCLUSIONS Deficits in duration discrimination, duration estimation, and intra-individual performance variability may have cascaded effects on the temporal organisation of behaviour in children and adolescents with ADHD and ADHD+RD.

Nutritional medicine as mainstream in psychiatry

Psychiatry is at an important juncture, with the current pharmacologically focused model having achieved modest benefits in addressing the burden of poor mental health worldwide. Although the determinants of mental health are complex, the emerging and compelling evidence for nutrition as a crucial factor in the high prevalence and incidence of mental disorders suggests that diet is as important to psychiatry as it is to cardiology, endocrinology, and gastroenterology. Evidence is steadily growing for the relation between dietary quality (and potential nutritional deficiencies) and mental health, and for the select use of nutrient-based supplements to address deficiencies, or as monotherapies or augmentation therapies. We present a viewpoint from an international collaboration of academics (members of the International Society for Nutritional Psychiatry Research), in which we provide a context and overview of the current evidence in this emerging field of research, and discuss the future direction. We advocate recognition of diet and nutrition as central determinants of both physical and mental health.

Impact of ADHD on the neurocognitive functioning of adolescents with bipolar disorder

BACKGROUND Pediatric Bipolar Disorder (BD) has been associated with a number of neurocognitive deficits not dissimilar to ADHD. This study compared neuropsychological profiles of 4 groups of adolescents (14-17 years): 41 Normal Controls (NC), 30 ADHD, 12 BD and 12 combined (BD+ADHD). METHODS Participants were identified according to a standardized protocol (WASHU-KSADS mood section, K-SADS-PL and Conners Scales) and completed tests of processing speed, memory, executive functioning, set shifting, and inhibition. ADHD adolescents on stimulant medication did not take it on the day. RESULTS After controlling for covariates, the ADHD-only and combined groups were most impaired, including processing and naming speed, working memory, and response inhibition. The ADHD-only group showed specific impairment in naming objects, numbers and letters than the NC and showed greater deficits than the BD-only group on tests of naming speed. The combined group showed greatest deficits in verbal memory and inhibitory control. Other than working memory, there were no differences between the BD-only and NC groups. Removal of BD-NOS did not impact on the results. CONCLUSIONS This study failed to find broad neurocognitive deficits in BD-only adolescents. Only those with comorbid ADHD showed cognitive deficits, highlighting the impact ADHD may have on neurocognitive functioning of BD.

Retrospective reports of childhood trauma in adults with ADHD

Objective: Although studies have documented higher prevalence of abuse in children with ADHD, no studies have investigated childhood reports of abuse in individuals identified with ADHD in adulthood. Method: Forty ADHD women, 17 ADHD males, 17 female controls, and 40 male controls complete the Childhood Trauma Questionnaire and other measures of psychosocial functioning. Results: Emotional abuse and neglect are more common among men and women with ADHD as compared to controls. Sexual abuse and physical neglect are more commonly reported by females with ADHD. Although childhood abuse is significantly correlated with depression and anxiety in adulthood, having ADHD is a better predictor of poorer psychosocial functioning in adulthood. Conclusion: Clinicians are alerted that patients with ADHD symptoms have a high probability of childhood abuse.

Nutrient supplementation approaches in the treatment of ADHD

Attention-deficit/hyperactivity disorder (ADHD) is a chronic, debilitating psychiatric illness that often co-occurs with other common psychiatric problems. Although empirical evidence supports pharmacological and behavioral treatments, side effects, concerns regarding safety and fears about long-term use all contribute to families searching for alternative methods of treating the symptoms of ADHD. This review presents the published evidence on supplementation, including single ingredients (e.g., minerals, vitamins, amino acids and essential fatty acids), botanicals and multi-ingredient formulas in the treatment of ADHD symptoms. In most cases, evidence is sparse, mixed and lacking information. Of those supplements where we found published studies, the evidence is best for zinc (two positive randomized, controlled trials); there is mixed evidence for carnitine, pycnogenol and essential fatty acids, and more research is needed before drawing conclusions about vitamins, magnesium, iron, SAM-e, tryptophan and Ginkgo biloba with ginseng. To date, there is no evidence to support the use of St John’s wort, tyrosine or phenylalanine in the treatment of ADHD symptoms. Multi-ingredient approaches are an intriguing yet under-researched area; we discuss the benefits of this approach considering the heterogeneous nature of ADHD.

Psychological functioning of women identified in adulthood with Attention-Deficit/ Hyperactivity Disorder

There are many adults being identified with Attention-Deficit/Hyperactivity Disorder (ADHD) who were not diagnosed as children. The current study investigated psychological functioning in women identified in adulthood as having ADHD. Participants were 102 women, aged 26 to 59, fulfilling (N = 51) and not fulfilling (N = 51) the criteria for ADHD. Home interviews were conducted, consisting of both structured questionnaires and semi-structured interviews. Results revealed that the women with ADHD reported more depressive symptoms, were more anxious and more stressed, had more external loci of control, had lower self-esteem, and engaged more in emotion-oriented and less in task-oriented coping strategies. This study emphasized the need to focus more research on females with ADHD and highlighted possible effects of a late diagnosis.

Broad-spectrum micronutrient formulas for the treatment of psychiatric symptoms: a systematic review

Ingesting minerals and vitamins in combination makes physiological sense, and research on the use of broad-spectrum formulations for psychiatric symptoms is increasing rapidly. This review covers formulas consisting of at least four vitamins and/or minerals and includes four experimental designs: randomized controlled trials, open-label trials, case–control studies and case studies with within-subject crossovers. Nevertheless, there is evidence for the efficacy of micronutrients in the treatment of stress and antisocial behaviors as well as depressed mood in nonclinical and elderly populations. Many reports studied mood changes in healthy populations, making it difficult to generalize to clinical samples. There is also preliminary support for the treatment of autism with micronutrients. However, despite positive preliminary findings, there are less data available to support efficacy of micronutrient formulas in treating bipolar disorder, attention deficit-hyperactivity disorder and substance abuse/dependence and no clinical trials have been done with clinically depressed or anxious patient samples, psychosis or eating disorders.