Adult attention-deficit/hyperactivity disorder treatment and cardiovascular implications

Psychiatric disorders and cardiovascular diseases: A mendelian randomization study

Background

Previous researches have demonstrated a connection between psychiatric disorders and cardiovascular diseases (CVDs), but the cause-and-effect relationship is still unclear. To that goal, the mendelian randomization (MR) method was used to study the causal link between psychiatric disorders and CVDs.

Methods

Genome-wide association studies (GWAS) data were collected for four CVDs, including coronary artery disease (n = 547,261), atrial fibrillation (n = 537,409), heart failure (n = 977,323) and ischemic stroke (n = 440,328). Summary data for four psychiatric disorders, including bipolar disorder (n = 51,710), major depressive disorder (n = 480,359), schizophrenia (n = 127,906) and attention deficit hyperactivity disorder (n = 55,374), came from the Psychiatric Genomics Consortium (PGC). All participants were European. The IVW method was mainly used, and the reliability of the results was increased using sensitivity analyses such as MR-Egger, Cochrane's Q test, MR-PRESSO and leave-one-out.

Results

MR revealed that the attention deficit hyperactivity disorder was linked to an increased risk of atrial fibrillation (OR, 1.085; 95% CI, 1.021-1.153; P = 0.008), heart failure (OR, 1.117; 95% CI, 1.044-1.195; P = 0.001), and ischemic stroke (OR, 1.146; 95% CI, 1.052-1.248; P = 0.002). The schizophrenia was linked to an increased risk of heart failure (OR, 1.035; 95% CI, 1.006-1.066; P = 0.017), but was found to be suggestively inverse associated with coronary artery disease (OR, 0.969; 95% CI, 0.941-0.997; P = 0.03). The major depressive disorder was associated with higher odds of coronary artery disease (OR, 1.109; 95% CI, 1.018-1.208; P = 0.018), while the bipolar disorder was linked to a reduced incidence of coronary artery disease (OR, 0.894; 95% CI, 0.831-0.961; P = 0.002) and heart failure (OR, 0.889; 95% CI, 0.829-0.955; P = 0.001). There were no clear relationships between other psychiatric disorders and CVDs.

Conclusion

The results provide genetic proof of a possible causal relationship between psychiatric disorders and CVDs. These results imply that psychiatric disorders may be the cause of some CVDs, and that some abnormal mental states may increase or reduce the likelihood of CVDs, providing guidance for the CVDs prevention.

Association of ADHD medications with the risk of cardiovascular diseases: a meta-analysis

This meta-analysis was conducted to evaluate the association between Attention deficit hyperactivity disorder (ADHD) medications and risk of sudden death/arrhythmia, stroke, myocardial infarction as well as all-cause death. We searched PubMed, Web of Science and China National Knowledge Infrastructure from 1950 to May 2018. All observational studies that the exposure of interest was ADHD medications, the outcome of interest was sudden death/arrhythmia, stroke, myocardial infarction as well as all-cause death, and the study reported relative risks (RRs) with 95% confidence intervals (95% CIs) were included. Pooled RRs were estimated by random-effects model. Subgroup analyses were conducted to examine the effects of study design, population, Country, follow-up duration, female proportion, covariates adjustment on the risk of sudden death/arrhythmia. Eight articles with ten studies (4,221,929 participants) were included in this meta-analysis about the association between ADHD medications and risk of sudden death/arrhythmia. The pooled RRs with 95% CIs of sudden death/arrhythmia for ADHD medications were 1.39 (1.06, 1.83). The result of the cohort study was 1.24 (0.84, 1.83). The pooled RRs between ADHD medications and stroke, myocardial infarction, all-cause death were 1.00 (0.74, 1.35), 0.91 (0.79, 1.05), 0.89 (0.54, 1.45), respectively. As for methylphenidate, the pooled RRs between methylphenidate and sudden death/arrhythmia, stroke, myocardial infarction, all-cause death were 1.46 (1.03, 2.07), 0.92 (0.70, 1.21), 0.97 (0.77, 1.23), 1.00 (0.49, 2.04), respectively. Based on the results of cohort studies, there was no correlation between ADHD medications and sudden death/arrhythmia, stroke, myocardial infarction and all-cause death. However, some of the confidence intervals do not exclude modest elevated risks, e.g., for sudden death/arrhythmia.

Cardiovascular Effects of Stimulant and Non-Stimulant Medication for Children and Adolescents with ADHD: A Systematic Review and Meta-Analysis of Trials of Methylphenidate, Amphetamines and Atomoxetine

BACKGROUND

Many children and adolescents with attention deficit/hyperactivity disorder (ADHD) are treated with stimulant and non-stimulant medication. ADHD medication may be associated with cardiovascular effects. It is important to identify whether mean group effects translate into clinically relevant increases for some individual patients, and/or increase the risk for serious cardiovascular adverse events such as stroke or sudden death.

OBJECTIVES

To evaluate potential cardiovascular effects of these treatments, we conducted a systematic review and meta-analysis of the effects of methylphenidate (MPH), amphetamines (AMP), and atomoxetine (ATX) on diastolic and systolic blood pressure (DBP, SBP) and heart rate (HR) in children and adolescents with ADHD.

METHODS

We conducted systematic searches in electronic databases (PsychINFO, EMBASE and Medline) to identify published trials which involved individuals who were (i) diagnosed with ADHD and were aged between 0-18 years; (ii) treated with MPH, AMP or ATX and (iii) had their DBP and SBP and/or HR measured at baseline (pre) and the endpoint (post) of the study treatment. Studies with an open-label design or a double-blind randomised control design of any duration were included. Statistical analysis involved calculating differences between pre- and post-treatment measurements for the various cardiovascular parameters divided by the pooled standard deviation. Further, we assessed the percentage of clinically relevant increased BP or HR, or documented arrhythmias.

RESULTS

Eighteen clinical trials met the inclusion criteria (10 for MPH, 5 for AMP, and 7 for ATX) with data from 5837 participants (80.7% boys) and average duration of 28.7 weeks (range 4-96 weeks). All three medications were associated with a small, but statistically significant pre-post increase of SBP (MPH: standard mean difference [SMD] 0.25, 95% confidence interval [CI] 0.08-0.42, p < 0.01; AMP: SMD 0.09, 95% CI 0.03-0.15, p < 0.01; ATX: SMD 0.16, 95% CI 0.04-0.27, p = 0.01). MPH did not have a pre-post effect on DBP and HR. AMP treatment was associated with a small but statistically significant pre-post increase of DBP (SMD 0.16, CI 0.03-0.29, p = 0.02), as was ATX treatment (SMD 0.22, CI 0.10-0.34, p < 0.01). AMP and ATX were associated with a small to medium statistically significant pre-post increase of HR (AMP: SMD 0.37, CI 0.13-0.60, p < 0.01; ATX: SMD 0.43, CI 0.26-0.60, p < 0.01). The head-to-head comparison of the three medications did not reveal significant differences. Sensitivity analyses revealed that AMP studies of <18 weeks reported higher effect sizes on DBP compared with longer duration studies (F(1) = 19.55, p = 0.05). Further, MPH studies published before 2007 reported higher effect sizes on SBP than studies after 2007 (F(1) = 5.346, p = 0.05). There was no effect of the following moderators: type of medication, doses, sample size, age, gender, type of ADHD, comorbidity or dropout rate. Participants on medication reported 737 (12.6%) other cardiovascular effects. Notably, 2% of patients discontinued their medication treatment due to any cardiovascular effect. However, in the majority of patients, the cardiovascular effects resolved spontaneously, medication doses were changed or the effects were not considered clinically relevant. There were no statistically significant differences between the medication treatments in terms of the severity of cardiovascular effects.

CONCLUSIONS

Statistically significant pre-post increases of SBP, DBP and HR were associated with AMP and ATX treatment in children and adolescents with ADHD, while MPH treatment had a statistically significant effect only on SBP in these patients. These increases may be clinically significant for a significant minority of individuals that experience larger increases. Since increased BP and HR in general are considered risk factors for cardiovascular morbidity and mortality during adult life, paediatric patients using ADHD medication should be monitored closely and regularly for HR and BP.

Attention Deficit/Hyperactivity Disorder (ADHD) Is Associated With Altered Heart Rate Asymmetry

Attention deficit/hyperactivity disorder (ADHD) is associated with complex neurocardiac integrity. We aimed to study heart rate time asymmetry as a nonlinear qualitative feature of heart rate variability indicating complexity of cardiac autonomic control at rest and in response to physiological stress (orthostasis) in children suffering from ADHD. Twenty boys with ADHD and 20 healthy age-matched boys at the age of 8 to 12 years were examined. The continuous ECG was recorded in a supine position and during postural change from lying to standing (orthostasis). Time irreversibility indices – Porta’s (P%), Guzik’s (G%) and Ehlers’ (E) – were evaluated. Our analysis showed significantly reduced heart rate asymmetry indices at rest (P%: 49.8 % vs. 52.2 %; G%: 50.2 % vs. 53.2 %; p<0.02), and in response to orthostatic load (P%: 52.4 % vs. 54.5 %, G%: 52.3 % vs. 54.5 %; p<0.05) associated with tachycardia in ADHD children compared to controls. Concluding, our study firstly revealed the altered heart rate asymmetry pattern in children suffering from ADHD at rest as well as in response to posture change from lying to standing (orthostasis). These findings might reflect an abnormal complex cardiac regulatory system as a potential mechanism leading to later cardiac adverse outcomes in ADHD.

Improving postapproval drug safety surveillance: getting better information sooner

Adverse drug events (ADEs) are an important public health concern, accounting for 5% of all hospital admissions and two-thirds of all complications occurring shortly after hospital discharge. There are often long delays between when a drug is approved and when serious ADEs are identified. Recent and ongoing advances in drug safety surveillance include the establishment of government-sponsored networks of population databases, the use of data mining approaches, and the formal integration of diverse sources of drug safety information. These advances promise to reduce delays in identifying drug-related risks and in providing reassurance about the absence of such risks.

Meta-analysis of increased heart rate and blood pressure associated with CNS stimulant treatment of ADHD in adults

Compared to children, adults with ADHD are at greater risk for developing adverse cardiovascular related outcomes and, if treated, may be likely to carry a greater burden of exposure to stimulant medications. The goal of this report is to critically review the available literature relevant to the cardiovascular safety of CNS stimulants for adult ADHD (aADHD). Twenty potential clinical trials of a CNS stimulant for aADHD have been published between 1979 and 2012. Of these, ten presented sufficient data to estimate the relative change in various cardiovascular parameters associated with ADHD treatment modalities. These trials were predominantly focused on long-acting stimulant preparations for acute symptom reduction (median duration=6 weeks, range: 4-24 weeks) and enrolled relatively young subjects (median age=36 years, range: 22-40). Using random effects meta-analysis, we found that subjects randomized to CNS stimulant treatment demonstrated a statistically significant increased resting heart rate [+5.7bpm (3.6, 7.8), p<0.001] and systolic blood pressure findings [+2.0mmHg (0.8, 3.2), p=0.005] compared with subjects randomized to placebo. There was a statistically significant increased risk for a resting heart rate >90bpm [4.2% (n=50) vs. 1.7% (n=8), OR=2.75 (1.3, 6.7), p=0.006] associated with CNS stimulant treatment. In light of prognostic value of resting heart rate with regard to cardiovascular morbidity in epidemiological studies, future research of adults with ADHD should focus on the potential clinical impact of the increase in heart rate observed in this meta-analysis.

A randomized, double-blind, placebo-controlled phase 2 study of α4β2 agonist ABT-894 in adults with ADHD

Dysregulation of the neuronal nicotinic acetylcholine receptor (NNR) system has been implicated in attention-deficit/hyperactivity disorder (ADHD), and nicotinic agonists improve attention across preclinical species and humans. Hence, a randomized, double-blind, placebo-controlled, crossover study was designed to determine the safety and efficacy of a novel α4β2 NNR agonist (ABT-894 (3-(5,6-dichloro-pyridin-3-yl)-1(S),5 (S)-3,6-diazabicyclo[3.2.0]heptane)) in adults with ADHD. Participants (N=243) were randomized to one of four dose regimens of ABT-894 (1, 2, and 4 mg once daily (QD)) or 4 mg twice daily (BID) or the active comparator atomoxetine (40 mg BID) vs placebo for 28 days. Following a 2-week washout period, participants crossed over to the alternative treatment condition (active or placebo) for an additional 28 days. Primary efficacy was based on an investigator-rated Conners' Adult ADHD Rating Scale (CAARS:Inv) Total score at the end of each 4-week treatment period. Additional secondary outcome measures were assessed. A total of 238 patients were assessed for safety end points, 236 patients were included in the intent-to-treat data set, and 196 were included in the completers data set, which was the prespecified, primary data set for efficacy. Both the 4 mg BID ABT-894 and atomoxetine groups demonstrated significant improvement on the primary outcome compared with placebo. Several secondary outcome measures were also significantly improved with 4 mg BID ABT-894. Overall, ABT-894 was well tolerated at all dose levels. These results provide initial proof of concept for the use of α4β2 agonists in the treatment of adults with ADHD. Further investigation of ABT-894, including higher doses, is therefore warranted.

Amphetamines, atomoxetine and the risk of serious cardiovascular events in adults

Main Objective

To compare the incidence rates of serious cardiovascular events in adult initiators of amphetamines or atomoxetine to rates in non-users.

Methods

This was a retrospective cohort study of new amphetamines (n = 38,586) or atomoxetine (n = 20,995) users. Each medication user was matched to up to four non-users on age, gender, data source, and state (n = 238,183). The following events were primary outcomes of interest 1) sudden death or ventricular arrhythmia, 2) stroke, 3) myocardial infarction, 4) a composite endpoint of stroke or myocardial infarction. Cox proportional hazard regression was used to calculate propensity-adjusted hazard ratios for amphetamines versus matched non-users and atomoxetine versus matched non-users, with intracluster dependence within matched sets accounted for using a robust sandwich estimator.

Results

The propensity-score adjusted hazard ratio for amphetamines use versus non-use was 1.18 (95% CI: 0.55–2.54) for sudden death/ventricular arrhythmia, 0.80 (95% CI: 0.44–1.47) for stroke, 0.75 (95% CI: 0.42–1.35) for myocardial infarction, and 0.78 (95% CI: 0.51–1.19) for stroke/myocardial infarction. The propensity-score adjusted hazard ratio for atomoxetine use versus non-use was 0.41 (95% CI: 0.10–1.75) for sudden death/ventricular arrhythmia, 1.30 (95% CI: 0.52–3.29) for stroke, 0.56 (95% CI: 0.16–2.00) for myocardial infarction, and 0.92 (95% CI: 0.44–1.92) for stroke/myocardial infarction.

Conclusions

Initiation of amphetamines or atomoxetine was not associated with an elevated risk of serious cardiovascular events. However, some of the confidence intervals do not exclude modest elevated risks, e.g. for sudden death/ventricular arrhythmia.

High dose methylphenidate treatment in adult attention deficit hyperactivity disorder: a case report

Introduction

Stimulant medication improves hyperactivity, inattention, and impulsivity in both pediatric and adult populations with Attention Deficit Hyperactivity Disorder (ADHD). However, data regarding the optimal dosage in adults is still limited.

Case presentation

We report the case of a 38-year-old Caucasian patient who was diagnosed with Attention Deficit Hyperactivity Disorder when he was nine years old. He then received up to 10 mg methylphenidate (Ritalin®) and 20 mg sustained-release methylphenidate (Ritalin SR®) daily. When he was 13, his medication was changed to desipramine (Norpramin®), and both Ritalin® and Ritalin SR® were discontinued; and at age 18, when he developed obsessive-compulsive symptoms, his medication was changed to clomipramine (Anafranil®) 75 mg daily. Still suffering from inattention and hyperactivity, the patient began college when he was 19, but did not receive stimulant medication until three years later, when Ritalin® 60 mg daily was re-established. During the 14 months that followed, he began to use Ritalin® excessively, both orally and rectally, in dosages from 4800-6000 mg daily. Four years ago, he was referred to our outpatient service, where his Attention Deficit Hyperactivity Disorder was re-evaluated. At that point, the patient’s daily Ritalin® dosage was reduced to 200 mg daily orally, but he still experienced pronounced symptoms of, Attention Deficit Hyperactivity Disorder so this dosage was raised again. The patient’s plasma levels consistently remained between 60–187 nmol/l—within the recommended range—and signs of his obsessive-compulsive symptoms diminished with fluoxetine 40 mg daily. Finally, on a dosage of 378 mg extended-release methylphenidate (Concerta®), his symptoms of Attention Deficit Hyperactivity Disorder have improved dramatically and no further use of methylphenidate has been recorded during the 24 months preceding this report.

Conclusions

Symptoms of Attention Deficit Hyperactivity Disorder (ADHD) in this adult patient, who also manifested a co-occurring obsessive compulsive disorder, dramatically improved only after application of a higher-than-normal dose of methylphenidate. We therefore suggest that clinicians consider these findings in relation to their adherence to current therapeutic guidelines.

ADHD medications and risk of serious cardiovascular events in young and middle-aged adults

CONTEXT

More than 1.5 million US adults use stimulants and other medications labeled for treatment of attention-deficit/hyperactivity disorder (ADHD). These agents can increase heart rate and blood pressure, raising concerns about their cardiovascular safety.

OBJECTIVE

To examine whether current use of medications prescribed primarily to treat ADHD is associated with increased risk of serious cardiovascular events in young and middle-aged adults.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective, population-based cohort study using electronic health care records from 4 study sites (OptumInsight Epidemiology, Tennessee Medicaid, Kaiser Permanente California, and the HMO Research Network), starting in 1986 at 1 site and ending in 2005 at all sites, with additional covariate assessment using 2007 survey data. Participants were adults aged 25 through 64 years with dispensed prescriptions for methylphenidate, amphetamine, or atomoxetine at baseline. Each medication user (n = 150,359) was matched to 2 nonusers on study site, birth year, sex, and calendar year (443,198 total users and nonusers).

MAIN OUTCOME MEASURES

Serious cardiovascular events, including myocardial infarction (MI), sudden cardiac death (SCD), or stroke, with comparison between current or new users and remote users to account for potential healthy-user bias.

RESULTS

During 806,182 person-years of follow-up (median, 1.3 years per person), 1357 cases of MI, 296 cases of SCD, and 575 cases of stroke occurred. There were 107,322 person-years of current use (median, 0.33 years), with a crude incidence per 1000 person-years of 1.34 (95% CI, 1.14-1.57) for MI, 0.30 (95% CI, 0.20-0.42) for SCD, and 0.56 (95% CI, 0.43-0.72) for stroke. The multivariable-adjusted rate ratio (RR) of serious cardiovascular events for current use vs nonuse of ADHD medications was 0.83 (95% CI, 0.72-0.96). Among new users of ADHD medications, the adjusted RR was 0.77 (95% CI, 0.63-0.94). The adjusted RR for current use vs remote use was 1.03 (95% CI, 0.86-1.24); for new use vs remote use, the adjusted RR was 1.02 (95% CI, 0.82-1.28); the upper limit of 1.28 corresponds to an additional 0.19 events per 1000 person-years at ages 25-44 years and 0.77 events per 1000 person-years at ages 45-64 years.

CONCLUSIONS

Among young and middle-aged adults, current or new use of ADHD medications, compared with nonuse or remote use, was not associated with an increased risk of serious cardiovascular events. Apparent protective associations likely represent healthy-user bias.