Treatment adherence and persistence in adult ADHD: Results from a twenty-four week controlled clinical trial with extended release methylphenidate

Factors Influencing the Medication Adherence in Adults With Attention-Deficit/Hyperactivity Disorder (ADHD) and Its Impact on Healthcare Utilization

OBJECTIVE

This study aims to investigate the factors influencing medication adherence among adults with Attention-Deficit/Hyperactivity Disorder (ADHD) and impact of central nervous system stimulants (CNS) adherence on healthcare utilization (HCU). Methods: This was a cross-sectional study using Medical Expenditure Panel Survey 2013 to 2019, with participants (≥18 years of age) with ADHD and had at least one CNS prescription. Multivariate logistic and linear regression were utilized to evaluate the medication adherence and its impact on HCU, respectively.

RESULT

Total 798 (10,718,005 weighted) ADHD patients, were mostly White (81%), aged between 18 and 25 (35%), and non-adherent to CNS (65%). The use of extended-release medications (OR = 1.51 [1.03, 2.23]) and new users (OR = 3.46 [2.12, 5.63], p ≤ .05) were positively associated with medication adherence. The adherent group utilized more outpatient visits (0.04 vs. 0.46) and prescription refills (18.38 vs. 31.25) compared to non-adherent.

CONCLUSION

Our findings can be applied to improve the medication adherence, patient education, and optimize intervention for adults with ADHD.

Long-term treatment of adult ADHD in a naturalistic setting: clinical predictors of attrition, medication choice, improvement, and response

Objectives: The aim of this study was to identify clinical predictors of treatment attrition, medication choice, improvement and response to pharmacotherapy in adult attention-deficit/hyperactivity disorder (ADHD). Methods: 150 ADHD patients were enrolled and naturalistically followed-up for at least 4 months. Conners' Adult ADHD Rating Scales-Observer: Screening Version (CAARS-O:SV) were used to measure ADHD severity. Results: 58 subjects (38.7%) were lost at follow-up, while 75 (50%) completed follow-up assessment, on average after 26.05 ± 11.99 weeks; 35 were treated with atomoxetine (ATX) and 40 with methylphenidate (MPH). Treatments were moderately effective (d = 0.72) and 37 patients (49.3%) were responders (≥30% CAARS-O:SV decrease). Patients lost at follow-up had lower inattentive symptoms, less generalized anxiety and family history of bipolar disorder, more amphetamine use disorder than follow-up completers. Compared to ATX-treated subjects, MPH-treated patients had greater severity of hyperactivity/impulsivity and were more frequently diagnosed with alcohol use disorder. While MPH and ATX showed similar efficacy, more pronounced improvements were observed in patients with combined ADHD, anxiety and substance use disorders. ADHD severity and comorbid substance use positively predicted response. Conclusions: Consensus-based hierarchical treatment of ADHD comorbidity is not consistently supported. Comorbid anxiety, mood and substance use disorders should not discourage the treatment of adult ADHD.

The role of sociodemographic and clinical factors in the initiation and discontinuation of attention deficit hyperactivity disorder medication among young adults in Sweden

Introduction

Long-term medication use is a recommended treatment for attention-deficit/hyperactivity disorder (ADHD), however, discontinuation is common. Non-medical factors which might influence initiation and discontinuation are understudied. Therefore, we investigated how different sociodemographic factors and comorbidities were associated with the initiation and discontinuation of ADHD medication use among young adults.

Methods and results

We conducted a population-based prospective cohort study using individually linked administrative register data, in which we included all individuals residing in Sweden, between the age of 19 and 29 who were first diagnosed with ADHD between January 2006 and December 2016 (n = 59224). ADHD medication initiation was defined as the first prescription of ADHD medication in the period from 3 months before to 6 months after the cohort entry date. Those who initiated ADHD medication were followed up for medication use until discontinuation, death/emigration, or until 2019. Logistic and Cox regression models were used to investigate the associations between sociodemographics, health-related predictors and initiation, as well as discontinuation. Overall, 48.7% of the 41399 individuals initiated ADHD medication, most often methylphenidate (87%). Among the initiators, 15462 (77%) discontinued medication use during the follow-up (median time: 150 days). After mutually adjusting all other predictors, initiation was positively associated with older age, male sex, higher level of education, and negatively associated with living at home with parents, immigrant status, being unemployed during the year before inclusion, being on disability pension, having autism, substance use, schizophrenia-spectrum disorders, other mental disability/developmental disorders, cardiovascular diseases or previous accidents. Discontinuation was positively associated with being born abroad, living in big cities, being unemployed during the year before inclusion, having cancer, and negatively associated with a higher educational level, having depression, anxiety or stress-related disorder, autism spectrum disorder or diabetes.

Conclusion

Besides medical factors, sociodemographics, such as educational attainment and immigrant status might also play a role in the initiation and discontinuation of ADHD medication use among young adults newly diagnosed with ADHD.

Treatments for child and adolescent attention deficit hyperactivity disorder in low and middle-income countries: A narrative review

BACKGROUND

Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder that affects approximately 2-7 % of children globally and is associated with a myriad of difficulties that have long-term consequences. Most children and adolescents live in low- and middle-income countries (LMICs), but there are few reports and no consolidation of findings on ADHD treatment outcomes in this population. We conducted a review of ADHD treatment literature for children and adolescents living in LMICs.

METHODS

Studies were identified using databases (PsychoINFO, Pubmed, MEDLINER, EMBASE, Global Health, Academic Search Complete, Google Scholar). The initial search produced 139 articles. These were filtered for language, title, abstract, and full-text keyword identification to yield a final 20 articles to be included in this review.

RESULTS

Reports on outcomes of both psychological and pharmacological treatment were relatively sparse, particularly the former, which mostly referred to parent training and multimodal programs in pre-school children. Most evidence exists for the benefit of methylphenidate-IR with a few reports on other agents, including clonidine, atomoxetine, and lisdexamfetamine. Methylphenidate is the most common agent to treat ADHD in youth in LMICs. Younger age, combined subtype, and comorbid oppositional defiant disorder were associated with poorer treatment outcome.

CONCLUSION

Access to treatment for ADHD is overall limited in LMICs and varied among individual countries. Pharmacological treatments were generally more available than psychological interventions. Several barriers including stigma, cost, and lack of resources were reported to impact treatment acceptance. More research in LMICs is needed to improve and expand mental health services in these regions.

Extended-release methylphenidate for attention deficit hyperactivity disorder (ADHD) in adults

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is a psychiatric diagnosis increasingly used in adults. The recommended first-line pharmacological treatment is central nervous system (CNS) stimulants, such as methylphenidate, but uncertainty remains about its benefits and harms.

OBJECTIVES

To assess the beneficial and harmful effects of extended-release formulations of methylphenidate in adults diagnosed with ADHD.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, nine other databases and four clinical trial registries up to February 2021. We searched 12 drug regulatory databases for clinical trial data up to 13 May 2020. In addition, we cross-referenced all available trial identifiers, handsearched reference lists, searched pharmaceutical company databases, and contacted trial authors.

SELECTION CRITERIA

Randomised, double-blind, parallel-group trials comparing extended-release methylphenidate formulations at any dose versus placebo and other ADHD medications in adults diagnosed with ADHD.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data. We assessed dichotomous outcomes as risk ratios (RRs), and rating scales and continuous outcomes as mean differences (MDs) or standardised mean differences (SMDs). We used the Cochrane risk of bias tool to assess risks of bias, and GRADE to assess the certainty of the evidence. We meta-analysed the data using a random-effects model. We assessed three design characteristics that may impair the trial results' 'generalisability'; exclusion of participants with psychiatric comorbidity; responder selection based on previous experience with CNS stimulants; and risk of withdrawal effects. Our prespecified primary outcomes were functional outcomes, self-rated ADHD symptoms, and serious adverse events. Our secondary outcomes included quality of life, ADHD symptoms rated by investigators and by peers such as family members, cardiovascular variables, severe psychiatric adverse events, and other adverse events.

MAIN RESULTS

We included 24 trials (5066 participants), of which 21 reported outcome data for this review. We also identified one ongoing study. We included documents from six drug regulatory agencies covering eight trials. Twenty-one trials had an outpatient setting and three were conducted in prisons. They were primarily conducted in North America and Europe. The median participant age was 36 years. Twelve trials (76% of participants) were industry-sponsored, four (14% of participants) were publicly funded with industry involvement, seven (10% of participants) were publicly funded, and one had unclear funding. The median trial duration was eight weeks. One trial was rated at overall unclear risk of bias and 20 trials were rated at overall high risk of bias, primarily due to unclear blinding of participants and investigators, attrition bias, and selective outcome reporting. All trials were impaired in at least one of the three design characteristics related to 'generalisability'; for example, they excluded participants with psychiatric comorbidity such as depression or anxiety, or included participants only with a previous positive response to methylphenidate, or similar drugs. This may limit the trials' usefulness for clinical practice, as they may overestimate the benefits and underestimate the harms. Extended-release methylphenidate versus placebo (up to 26 weeks) For the primary outcomes, we found very low-certainty evidence that methylphenidate had no effect on 'days missed at work' at 13-week follow-up (mean difference (MD) -0.15 days, 95% confidence interval (CI) -2.11 to 1.81; 1 trial, 409 participants) or serious adverse events (risk ratio (RR) 1.43, CI 95% CI 0.85 to 2.43; 14 trials, 4078 participants), whereas methylphenidate improved self-rated ADHD symptoms (small-to-moderate effect; SMD -0.37, 95% CI -0.43 to -0.30; 16 trials, 3799 participants). For secondary outcomes, we found very low-certainty evidence that methylphenidate improved self-rated quality of life (small effect; SMD -0.15, 95% CI -0.25 to -0.05; 6 trials, 1888 participants), investigator-rated ADHD symptoms (small-to-moderate effect; SMD -0.42, 95% CI -0.49 to -0.36; 18 trials, 4183 participants), ADHD symptoms rated by peers such as family members (small-to-moderate effect; SMD -0.31, 95% CI -0.48 to -0.14; 3 trials, 1005 participants), and increased the risk of experiencing any adverse event (RR 1.27, 95% CI 1.19 to 1.37; 14 trials, 4214 participants). We rated the certainty of the evidence as 'very low' for all outcomes, primarily due to high risk of bias and 'indirectness of the evidence'. One trial (419 participants) had follow-up at 52 weeks and two trials (314 participants) included active comparators, hence long-term and comparative evidence is limited.

AUTHORS' CONCLUSIONS

We found very low-certainty evidence that extended-release methylphenidate compared to placebo improved ADHD symptoms (small-to-moderate effects) measured on rating scales reported by participants, investigators, and peers such as family members. Methylphenidate had no effect on 'days missed at work' or serious adverse events, the effect on quality of life was small, and it increased the risk of several adverse effects. We rated the certainty of the evidence as 'very low' for all outcomes, due to high risk of bias, short trial durations, and limitations to the generalisability of the results. The benefits and harms of extended-release methylphenidate therefore remain uncertain.

Attention-Deficit/Hyperactivity Disorder Medication Adherence in the Transition to Adulthood: Associated Adverse Outcomes for Females and Other Disparities

PURPOSE

The purpose of this study was to assess the association between attention-deficit/hyperactivity disorder (ADHD) medication adherence and adverse health outcomes in older adolescents transitioning to adulthood.

METHODS

In a cohort of 17-year-old adolescents with ADHD at Kaiser Permanente Northern California, we assessed medication adherence (medication possession ratio ≥70%) and any medication use and associations with adverse outcomes at 18 and 19 years of age. We conducted bivariate tests of association and multivariable logistic regression models.

RESULTS

Adherence declined from 17 to 19 years of age (36.7%-19.1%, p < .001). Non-white race/ethnicity, lower estimated income, and male sex were associated with nonadherence. Model results show nonadherent females experienced several adverse outcomes: Adherence at 18 years of age (referent: nonadherence) was associated with lower odds of pregnancy (adjusted odds ratio [AOR]: .13, 95% confidence interval [CI]: .03-.54). Any use (referent: nonuse) at 18 years of age was associated with lower odds of sexually transmitted infections among females (AOR: .39, 95% CI: .19-.83), pregnancies (AOR: .26, 95% CI: .13-.50), emergency department visits (AOR: .69, 95% CI: .55-.85), and greater odds of injuries (AOR: 1.16, 95% CI: 1.02-1.32). Adherence at 19 years of age was associated with lower odds of pregnancy (AOR: .13, 95% CI: .02-.95). Any use at 19 years of age was associated with lower odds of injury in females (AOR: .77, 95% CI: .60-.99) pregnancy (AOR: .35, 95% CI: .16-.78), and, in both sexes, substance use (AOR: .71, 95% CI: .55-.92).

CONCLUSIONS

Late adolescence is associated with decline in ADHD medication use and adherence. ADHD medication adherence and any ADHD medication use is associated with fewer adverse health outcomes, particularly in females.

Methylphenidate Treatment Adherence and Persistence in Children in the Netherlands

Objectives: Numerous studies have examined determinants contributing to methylphenidate adherence and persistence, but these were mainly conducted in adults. These determinants are likely to be different in children as they usually rely on their parents to provide them with the care they need. The objective was to study child and family characteristics as determinants of methylphenidate adherence and persistence in children. Methods: The study population consists of 307 children from the Generation R Study in the Netherlands, who had at least one dispensing record of methylphenidate until the age of 16 years. Adherence was defined as a medication possession ratio ≥0.80 up to 2 years after treatment initiation. Persistence was defined as the duration of treatment until a discontinuation period of ≥6 months. Family and child characteristics were tested as determinants of adherence with multivariable logistic regression analysis. Persistence was evaluated using a Kaplan-Meier analysis. Results: Children of mothers with one child (adjusted odds ratio [OR]: 2.31, 95% confidence interval [CI]: 1.17-4.54) or of mothers with an average household income (compared to high) were more likely to be adherent (adjusted OR: 3.45, 95% CI: 1.43-8.31). Children who started treatment at the age of 12-16 years (compared to <12 years) (adjusted hazard ratio [HR]: 3.55, 95% CI: 2.54-4.98) and girls (adjusted HR: 1.44, 95% CI: 1.07-1.95) were more often nonpersistent. Conclusion: Both child and family characteristics may play a role in methylphenidate treatment adherence. Furthermore, gender and the start age of treatment were found to be associated with nonpersistence. These findings may be important for health care professionals when initiating methylphenidate treatment in children.

Treatment of ADHD in adults - prevalence of discontinuation and associated factors - results from a cross-sectional analysis of Danish register data

BACKGROUND

A growing number of adults are receiving pharmacological treatment for ADHD but a sizable proportion also discontinues or have gaps in treatment. The primary aims of this study were to identify how many patients treated for ADHD in adulthood, have at least one event of discontinuation in treatment and to identify possible associated variables.

METHODS

Within the Danish population aged 18-60 years on the 1st of January 2013, we identified the number of individuals who had been prescribed ADHD-medication at least once during the 1st of January 2002-31st of December 2013 using Danish register data. Among those who filed more than one prescription, treatment discontinuation was defined as having more than 211 days between two prescriptions. In crude and adjusted logistic regression analysis, we explored potential associations to discontinuation for variables such as gender and age at treatment initiation.

RESULTS

In a population, if N = 3,165,844 individuals, n = 42,892 had received at least one prescription for ADHD medication. Among those with more than one prescription (N = 38,289), 29.4% had discontinued their treatment at least once, according to our definition of treatment discontinuation. ADHD treatment discontinuation was associated with being male, unemployment, lower educational attainment, receiving incapacity benefits and younger age at treatment initiation (p < 0.001).

CONCLUSIONS

A large proportion of individuals treated for ADHD had at least one discontinuation of treatment according to our definition. Although the present study does not allow for investigating the direction of these effects, nor whether some patients later resumed treatment, having at least one discontinuation was associated with a range of variables relating to e.g. age and gender, and provides an emerging profile for clinicians of patients more likely to discontinue.

Examining Breaks and Resistance in Medication Adherence Among Adolescents With ADHD as Associated With School Outcomes

Objective: Pharmacological interventions combined with behavioral treatment have been associated with better outcomes for children with ADHD. Yet, as children age into adolescence and gain autonomy, they may choose not to adhere to taking a prescribed medication. The purpose of the current study was to examine school outcomes among adolescents with ADHD who take medication breaks versus resisting medication with respect to grades and school behaviors. Method: We statistically controlled for a variety of variables such as the child's age, sex, the presence of side effects, and parent's relationship with child. Approximately half of the sample of adolescents with ADHD exhibited some form of medication nonadherence. Results: The results of the current study suggest that more positive school outcomes in terms of behaviors and grades are associated with adolescents taking breaks from their ADHD medication rather than resisting their medication. Conclusion: This result would indicate that not all forms of medication nonadherence have the same association with school outcomes in terms of grades and behaviors.

[Pharmacotherapy of attention deficit hyperactivity disorder in adults]

Pharmacotherapy is a central component in the context of an overall therapeutic concept in the treatment of adults with attention deficit hyperactivity disorder (ADHD). In this concept psychosocial interventions with psychoeducation or specific psychotherapy measures also play an important role. In adults three compounds are currently approved for the pharmacological treatment of ADHD in Germany. The long-acting stimulants retarded methylphenidate preparations and lisdexamfetamine can be prescribed. Alternatively, the adrenergic uptake inhibitor atomoxetine can be used. In several meta-analyses good effectiveness and tolerance of these drugs on ADHD psychopathology has been shown. They also improve ADHD-related disorders of emotional regulation capability and disorganization in everyday life. Importantly, an improvement in everyday functionality and quality of life under medication could also be shown in several studies. In this review the evidence for pharmacotherapy of ADHD and its implementation into treatment of adult patients is presented.

Exploring factors influencing initiation, implementation and discontinuation of medications in adults with ADHD

Background

Adherence to ADHD medication is a complex phenomenon as the decision to adhere is influenced by a range of factors. To design tailored interventions to promote adherence, it is important to understand the factors that influence adherence in the context of its three phases: initiation, implementation and discontinuation.

Objective

The objective of this study was to explore the phase‐specific factors that influence adherence to medication in adults who have a diagnosis of ADHD.

Methods

Three focus groups (FGs) were conducted with twenty adults with ADHD in different metropolitan areas of Sydney, Australia. FGs were transcribed verbatim and thematically analysed.

Results

Participants’ decision to initiate medication (the initiation phase) was influenced by their perceived needs (desire to improve academic and social functioning) and concerns (fear of side‐effects) about medication following a similar process as defined by the Necessity‐Concerns Framework (NCF). The balance between benefits of medication (needs) and side‐effects (concerns) continued to determine participants’ daily medication‐taking (the implementation phase) and persistence (or discontinuation) with their medication. Forgetfulness and stigma were reported as concerns negatively impacting the implementation phase, while medication cost and dependence influenced the discontinuation phase of adherence.

Conclusions

Adults’ decision to initiate, continue or discontinue medication is influenced by a range of factors; some are unique to each phase while some are common across the phases. Participants balanced the needs for the medication against their concerns in determining whether to adhere to medication at each phase. It appears that the NCF has applicability when decision making about medication is explored at the three phases of adherence.

A Review of Factors Influencing the Three Phases of Medication Adherence in People with Attention-Deficit/Hyperactivity Disorder

Objectives: Factors affecting adherence to medications in people with attention-deficit/hyperactivity disorder (ADHD) are not well understood in the context of their influence on the different phases of adherence, that is, initiation, implementation, and discontinuation. This review aimed to identify the factors affecting the three phases of medication adherence in people with ADHD. Methods: Six electronic databases, including Medline, PubMed, IPA, CINAHL, Embase, and PsycINFO, were systematically searched from inception through October 2018 with the limitations of English language and human studies. The search strategy was based on three concepts (adherence, ADHD, and factors) and their relevant terminologies. Results: Considerable variability was observed with regards to the criteria used to define adherence in identified studies (n = 48). Most studies focused on the implementation phase of adherence (n = 27), while only a handful focused on the initiation (n = 6) and discontinuation (n = 5) phase of adherence. The remaining studies (n = 10) examined multiple phases of adherence. Conflicting information received about medication, medication frequency, and fears of medication's effect on growth were the unique factors impacting initiation, implementation, and discontinuation, respectively. Moreover, factors within each phase of adherence also differed with different populations such as parents, children, adolescents, and adults. Fear of addiction, medication effectiveness, psychiatric comorbidity, and medication side effects were the most common factors identified in all three phases of adherence. Conclusions: This review found some unique factors in each phase of adherence while some overlap was also noted. Future interventions to improve adherence should be phase- and group specific rather than consider adherence as a single variable.

Randomised sham-controlled study of high-frequency bilateral deep transcranial magnetic stimulation (dTMS) to treat adult attention hyperactive disorder (ADHD): Negative results

OBJECTIVES

Recent studies support the possible effectiveness of repetitive transcranial magnetic stimulation (rTMS) as a treatment for attention deficit hyperactivity disorder (ADHD). The objective of this study was to evaluate the safety and possible efficacy of bilateral prefrontal deep rTMS for the treatment of adult ADHD.

METHODS

Twenty-six adult ADHD patients were randomised blindly to sham or actual deep TMS (dTMS). Twenty daily sessions were conducted using the bilateral H5 dTMS coil (Brainsway, IL) in order to stimulate the prefrontal cortex at 120% of the motor threshold at high frequency. For assessment, Conners' Adult ADHD Rating Scale questionnaire and a computerised continuous performance test, Test of Variables of Attention, were used.

RESULTS

No differences in clinical outcomes were detected between the actual dTMS and sham groups.

CONCLUSIONS

The presented evidence does not support the utility of bilateral prefrontal stimulation to treat adult ADHD. Due to the small sample size, caution must be exercised in interpreting our preliminary findings.

Attention-deficit/hyperactivity disorder symptom clusters differentially predict prenatal health behaviors in pregnant women

OBJECTIVE

To date, most investigations of mental health in pregnant women have focused on depression or substance use. This study aimed to (a) delineate the relationships between symptoms of attention-deficit/hyperactivity disorder (ADHD) and prenatal health behaviors and (b) explore whether the symptom clusters of ADHD differentially predict prenatal health behaviors (e.g., physical strain, healthy eating, prenatal vitamin use).

METHOD

A total of 198 pregnant women (mean age = 27.94 years) completed measures of ADHD symptoms, prenatal health behaviors, and depression.

RESULTS

Inattention, hyperactivity, and impulsivity/emotional lability all evidenced significant relationships with the prenatal health behaviors, each differentially predicting different prenatal health behaviors.

CONCLUSION

As decreased engagement in adequate prenatal health behaviors puts both the mother and fetus at risk for negative birth outcomes, future research should work to develop a brief ADHD screen to be used in obstetric clinics and should investigate these relationships within a sample of women with a diagnosis of ADHD.

Six-year outcome in subjects diagnosed with attention-deficit/hyperactivity disorder as adults

There are very few studies on the long-term outcome in subjects diagnosed with ADHD as adults. The objective of the present study was to assess this and relate the outcome to whether there was current medication or not and to other potential predictors of favourable outcome. A prospective clinical cohort of adults diagnosed with ADHD according to DSM-IV criteria was followed-up on an average of 6 years after first evaluation (n = 124; mean age 42 years, 51% males). ADHD symptom trajectories were assessed as well as medication, global functioning, disability, health-related quality of life, and alcohol and drug consumption at follow-up. Ninety percent of those diagnosed were initially treated pharmacologically and half of them discontinued treatment. One-third reported remission, defined as not fulfilling any ADHD subtype and a GAF-value last year ≥ 70, which was not affected by comorbidity at baseline. Current medication was not associated with remission. Subjects evaluated and first diagnosed with ADHD as adults are functionally improved at follow-up 6 years later despite a high percentage of psychiatric comorbidity at baseline. Half dropped out of medication, and there was no difference in ADHD remission between subjects with on-going medication at follow-up or subjects without medication, although current medication was related to a higher degree of self-reported global improvement.

Predictors of relapse or maintenance of response in pediatric and adult patients with attention-deficit/hyperactivity disorder following discontinuation of long-term treatment with atomoxetine

We identified relapse/maintenance-of-response (MOR) predictors following discontinuation of long-term atomoxetine treatment in pediatric and adult patients with attention-deficit/hyperactivity disorder (ADHD) and assessed correlations between ADHD symptoms and quality of life (QoL). Post hoc analyses of data from two randomized, double-blind, placebo-controlled, phase 3 withdrawal studies in patients with ADHD meeting predefined response criteria before randomization. Study 1: patients (N = 163; 6-15 years) received atomoxetine (1.2-1.8 mg/kg/day) for 1 year, followed by randomization to atomoxetine (n = 81) or placebo (n = 82) for 6 months. Study 2: patients (N = 524; 18-50 years) received atomoxetine (80-100 mg/day) for ~6 months, followed by randomization to atomoxetine (n = 266) or placebo (n = 258) for ~6 months. Placebo patients were used for the analyses. Relapse: ≥50% worsening of prerandomization improvement in ADHD symptoms and ≥2 level severity increase on the Clinical Global Impression-Severity (CGI-S) scale at 2 consecutive visits; MOR: retaining ≥75% of prerandomization symptom improvement and CGI-S ≤ 2 at all visits (study 1); retaining ≥70% of prerandomization symptom improvement and CGI-S ≤ 3 at all visits (study 2). In adults, statistically significantly (P ≤ .05) increased likelihood of relapse was associated with prerandomization presence of Conners' Adult Attention-Deficit/Hyperactivity Disorder Rating Scale-Investigator-Rated:Screening Version (CAARS-Inv:SV) items "difficulty awaiting turn" and "careless mistakes." In pediatric patients, less MOR was associated with prerandomization presence of ADHD Rating Scale-IV-Parent Version Investigator-Rated item "does not listen"; in adults, less MOR was associated with prerandomization presence of CAARS-Inv:SV items "loses things" and "difficulty awaiting turn." Changes in patients' QoL after withdrawal from atomoxetine moderately correlated with changes in ADHD symptoms in pediatric patients and mildly in adults.

Clinical and neurobiological factors in the management of treatment refractory attention-deficit hyperactivity disorder

Attention-deficit/hyperactivity disorder (ADHD) is a highly prevalent mental disorder of childhood, which often continues into adolescence and adulthood. Stimulants such as methylphenidate (MPH) and non-stimulants such as atomoxetine are effective medications for the treatment of ADHD. However, about 30% of patients do not respond to these medications. Pharmacological treatment for ADHD, although highly effective, is associated with marked variabilities in clinical response, optimal dosage needed and tolerability. This article provides an overview of up-to-date knowledge regarding the clinical and neurobiological factors which contribute to and help predict treatment-refractory ADHD. Pharmacogenetic, pharmacogenomics and neuroimaging studies are still controversial with respect to determining the associations between response to medication and genetic factors, thereby resulting in hypotheses that differences in the genetic factors and neuroimaging findings contribute to treatment outcome. Much research on the potential role of genotype in pharmacological effects has focused on the catecholaminergic gene related to executive functions. Many neuroimaging studies have also reported a relationship between treatment response and common patterns of brain structure or activity according to various genetic polymorphisms. When children, adolescents and adults with ADHD do not respond to MPH, we should consider additional pharmacological options, including other classes of psychostimulants, the nonstimulant atomoxetine, bupropion, tricyclic antidepressant, clonidine, guanfacine and lisdexamphetamine. Prudent choice of an appropriate medication and active engagement of children, parents, and teachers in daily management may help to ensure long-term adherence. Therefore, additional research might help to optimize the treatment of children, adolescents and adults with ADHD and to find new options for the treatment of patients who do not respond to stimulants and the other medications. Because these findings should be interpreted cautiously, further studies are needed to elucidate these issues more clearly.

Factors Associated With Adherence to Methylphenidate Treatment in Adult Patients With Attention-Deficit/Hyperactivity Disorder and Substance Use Disorders

Adherence to treatment is one of the most consistent factors associated with a favorable addiction treatment outcome. Little is known about factors associated with treatment adherence in individuals affected with comorbid attention-deficit/hyperactivity disorder and substance use disorders (SUD). This study aimed to explore whether treatment-associated factors, such as the prescribing physician's (sub)specialty and methylphenidate (MPH) dose, or patient-related factors, such as sex, age, SUD subtype, and psychiatric comorbidity, were associated with adherence to MPH treatment. Swedish national registers were used to identify adult individuals with prescriptions of MPH and medications specifically used in the treatment of SUD or a diagnosis of SUD and/or coexisting psychiatric diagnoses. Primary outcome measure was days in active MPH treatment in stratified dose groups (≤36 mg, ≥37 mg to ≤54 mg, ≥55 mg to ≤72 mg, ≥73 mg to ≤90 mg, ≥91 mg to ≤108 mg, and ≥109 mg). Lower MPH doses (ie, ≤36 mg day 100) were associated with treatment discontinuation between days 101 and 830 (HR≤36 mg, 1.67; HR37-54mg, 1.37; HR55-72mg, 1.36; HR73-90mg, 1.19; HR≥108mg, 1.09). The results showed a linear trend (P < 0.0001) toward decreased risk of treatment discontinuation along with increase of MPH doses. In conclusion, this study shows that higher MPH doses were associated with long-term treatment adherence in individuals with attention-deficit/hyperactivity disorder and SUD.

Post Hoc Analysis of Potential Predictors of Response to Atomoxetine for the Treatment of Adults with Attention-Deficit/Hyperactivity Disorder using an Integrated Database

BACKGROUND

Responses to atomoxetine vary for individual patients with attention-deficit/hyperactivity disorder (ADHD). However, we do not know whether any factors can be used to reliably predict how individuals with ADHD will respond to treatment.

OBJECTIVE

Our objective was to evaluate background variables that facilitate early identification of those adults with ADHD who are likely to respond to treatment with atomoxetine.

METHODS

We pooled data for atomoxetine-treated adults with ADHD from 12 clinical trials for a short-term (10-week) analysis, and from 11 clinical trials for a long-term (24-week) analysis. Patients not meeting a response definition [≥30 % reduction in Conners' Adult ADHD Rating Scales-Investigator Rated: Screening Version (CAARS-Inv:SV) total score and Clinical Global Impressions of ADHD Severity Scale (CGI-S) score ≤3 at endpoint], or who discontinued, were defined as non-responders. Another definition of response (≥30 % reduction in CAARS-Inv:SV total score at endpoint) was also used in these analyses; only the results with the former definition are shown in this abstract, as the same conclusions were gained with both definitions. A treatment-specified subgroup detection tool (a resampling-based ensemble tree method) was used to identify predictors of response.

RESULTS

Of 1945 adults in the long-term analysis, 548 (28.2 %) were responders to atomoxetine at week 24; 65.2 % of 1397 non-responders had discontinued. Of 4524 adults in the short-term analysis, 1490 (32.9 %) were responders at week 10; 33.2 % of 1006 non-responders had discontinued. No analyzed baseline parameters (age, sex, prior stimulant use, ADHD subtype, CAARS-Inv:SV, CGI-S) were statistically significant predictors of response. Reductions in CAARS-Inv:SV total, CAARS-Inv:SV subscores, and CGI-S at week 4 in the short-term analysis, and at weeks 4 or 10 in the long-term analysis, were statistically significant predictors of response, i.e., patients with versus without these reductions early in treatment were more likely to be clinical responders at later time points. Sensitivity ranged from 28.6 to 85.9 %, and specificity ranged from 23.8 to 86.7 %. Predictors with higher sensitivity had lower specificity, and vice versa.

CONCLUSIONS

Reductions in CAARS-Inv:SV and CGI-S scores at weeks 4 and 10 are statistically significant predictors of response to atomoxetine at later time points in adults with ADHD. However, the predictors identified by these analyses are not reliable enough for use in clinical practice. The only currently available method to judge whether individuals with ADHD will respond to atomoxetine is to start treatment and assess the response over an extended period, sometimes longer than 10 weeks.

Prediction of methylphenidate treatment outcome in adults with attention-deficit/hyperactivity disorder (ADHD)

Attention-deficit/hyperactivity disorder (ADHD) is a highly prevalent mental disorder of childhood, which often persists in adulthood. Methylphenidate (MPH) is one of the most effective medications to treat ADHD, but also few adult patients show no sufficient response to this drug. In this paper, we give an overview regarding genetic, neuroimaging, clinical and other studies which have tried to reveal the reasons for non-response in adults with ADHD, based on a systematic literature search. Although MPH is a well-established treatment for adults with ADHD, research regarding the prediction of treatment outcome is still limited and has resulted in inconsistent findings. No reliable neurobiological markers of treatment response have been identified so far. Some findings from clinical studies suggest that comorbidity with substance use disorders and personality disorders has an impact on treatment course and outcome. As MPH is widely used in the treatment of adults with ADHD, much more work is needed regarding positive and negative predictors of long-term treatment outcome in order to optimize the pharmacological treatment of adult ADHD patients.

Myocardial injury in a 41-year-old male treated with methylphenidate: a case report

Background

Elevated cardiac troponin levels are consistent with the diagnosis of an acute coronary syndrome, but may also represent adverse drug reactions. Psychostimulating drugs raise both blood pressure and heart rate, and case reports of sudden death, stroke, and myocardial infarction have led to regulatory and public concern about the cardiovascular safety of these drugs.

Case presentation

We present a case where a 41-year-old Norwegian male with radiating chest pain, elevated troponins, and supraventricular tachycardia was hospitalized. Tentative diagnosis was acute coronary syndrome. Percutaneous coronary angiography, but not cardiac magnetic resonance imaging, was performed and medical antiplatelet treatment started. Because of an attention deficit/hyperactivity disorder the patient had recently increased his dose of methylphenidate, but still within the therapeutic dose range. Apart from venlafaxine, also in a therapeutic dose, the patient took no other drugs. An acute coronary syndrome was excluded during hospitalization, and a drug effect was suspected.

Conclusions

When interpreting troponin results it is important to take into account the context of the patient’s clinical presentation, including the possibility of adverse drug reactions. The adverse drug reaction could include a combination of vasospasm and/or increased oxygen demand due to tachycardia. This case should be borne in mind before a diagnosis of myocardial infarction is given, or a decision to perform invasive coronary angiography is made in patients that use methylphenidate or related substances. Cardiac magnetic resonance imaging could be of diagnostic value in such cases.