Methylphenidate Prescriptions Research Articles

Birth month as predictor of ADHD medication use in Dutch school classes

Several international studies have shown that pupils who are comparatively young within their year group have a greater likelihood of being diagnosed with ADHD and receiving ADHD medication. The findings suggest that comparatively young but age-appropriate behaviour some pupils show in school may be confused with ADHD. This study investigates whether this noted association between birth month and ADHD medication is also found in the Netherlands; and if so, whether GPs (general practitioners) and teachers are aware of this association. Over 2000 birth dates of children between the ages of 5 and 12 were collected from GP client files. The data included whether children are prescribed methylphenidate, the most commonly used medication for ADHD. These data were analysed by descriptive statistics (graphs) and evaluative statistics (logistic regression analysis and relative risk). GPs and teachers were invited by questionnaire to report whether they knew of the association between birth month and ADHD. A significant correlation between birth month and methylphenidate prescription are found. Relatively young pupils are 2.43 times more likely to be prescribed methylphenidate than their older classmates. A majority of GPs and teachers report not being aware of an association between birth month and ADHD medication.

Methylphenidate misuse in adult patients and the impact of therapeutic use.

Methylphenidate (MPH) prescription rates for adults increase, but the extent of a parallel rise in toxic exposures and their causes and distribution between different MPH trade names are unexplored. We retrospectively analyzed adult MPH exposures reported to the Danish Poison Information Centre from January 2006 to July 2012 and the association with MPH sales and the number of patients prescribed MPH. Of the 394 exposures (57% males, median age 27 years) reported, MPH status was available in 249 of whom 65.5% were prescribed MPH. Exposure was in 54% motivated by suicidal attempt and in 40% by recreational use (based on 375 cases). Exposure was dominated by one trade name and exposure incidence correlated significantly with sales ( p = 0.001) and prevalence of MPH-treated patients ( p = 0.0008). The increase in MPH exposures parallels the prescription rates (particularly Ritalin(®)/Ritalin(®) Uno). Most exposures were intentional and motivated by suicide attempts or recreational use.

Changing Epidemiology of Methylphenidate Prescriptions in the Community: A Multifactorial Model

Objective: To examine dispensing patterns of methylphenidate (MPH) to determine how socioeconomic status (SES), ethnocultural affiliation, and gender affect the medical treatment of ADHD. Method: We reviewed MPH prescription records for year 2011 of children aged 6 to 18, from regional pharmacies serving homogeneous neighborhoods. Results: MPH prescriptions showed an increase in prevalence from 4.2% to 7.5% in the years 2007 to 2011, respectively. Jewish children were four times more likely to be prescribed MPH than Arab children, with significant discrepancies along SES and gender lines (p < .001). Higher SES and male gender were associated with greater use of MPH. General pediatric prescription rates of MPH in all communities increased by 85%, compared with year 2007 statistics (p < .001). Conclusion: Prescription patterns for MPH in children reflect diagnostic patterns of ADHD that appear to be heavily influenced by additive factors of SES, cultural attitudes, and gender. Dispensing data provide valuable information for targeting underserved groups and defining potential areas of abuse.

Drug holiday utilisation in ADHD-diagnosed children and adolescents in South Africa

ObjectiveAttention deficit hyperactivity disorder (ADHD) is a prevalent disorder affecting people in all age groups. Pharmacological treatment with psychostimulants, specifically methylphenidate, is first line management. The ideal dosing regimen of methylphenidate is debatable with daily use being considered harmful by many. However, it is unknown if sporadic drug withdrawal is beneficial to management. The primary aim was to investigate drug holiday utilisation incidence.MethodThe study comprised a drug utilisation review (DUR) and questionnaire-based survey. The DUR was conducted using a corporate retail pharmacy group database. Methylphenidate prescriptions were evaluated to determine possible drug holiday use through different analyses of dispensing patterns. The survey included several questions relating to drug holiday use.ResultsDrug holiday use was identified in both study populations. Weekends and school holidays were identified as common periods for drug holiday observation. Of the participants that provided reasons for drug holiday utilisation, half indicated that methylphenidate was only necessary for school activities. DUR results indicated that drug holidays appeared to be more commonly observed during March and December.ConclusionsReasons for drug holiday utilisation were variable. This study recommends that these drug free periods are only observed if shown to be beneficial to the patient.

First-Trimester Exposure to Methylphenidate

The use of methylphenidate to treat attention-deficit/hyperactivity disorder has risen dramatically in Western countries, and it is increasingly used by adults, including women of childbearing age. Very little is known about potential hazards of in utero exposure to methylphenidate. We conducted this study to estimate the risk of major congenital malformations following first-trimester in utero exposure to methylphenidate. Data from 2005 to 2012 were extracted from the Danish National Patient Register, the Danish National Prescription Registry, the Medical Birth Registry, and the Danish Civil Registration System. Exposure was defined as having redeemed 1 or more prescriptions for methylphenidate within a time window defined as 14 days before the beginning of the first trimester up to the end of the first trimester. Each exposed subject was propensity score-matched to 10 unexposed subjects with respect to maternal age, smoking status, body mass index, length of education, calendar year of completion of pregnancy, and concomitant use of antipsychotics, antidepressants, anxiolytics, and nonsteroidal anti-inflammatory drugs. We included 222 exposed and 2,220 unexposed pregnancies in the analysis. There was no statistically significant increase in major malformations (point prevalence ratio = 0.8; 95% CI, 0.3-1.8) or cardiac malformations (point prevalence ratio = 0.9; 95% CI, 0.2-3.0). Sensitivity analyses using different definitions of exposure or previous users of methylphenidate as the unexposed comparison cohort yielded comparable results. First-trimester in utero exposure to methylphenidate does not appear to be associated with a substantially (ie, more than 2-fold) increased overall risk of major congenital malformations.

EPA-0748 – Methylphenidate abuse: results of a french survey

Introduction Methylphenidate (MPH) abuse is well established especially among young people in USA. In France, MPH is indicated in treatment for attention deficit/hyperactivity disorder (ADHD) in children and narcolepsy in children and adults. Since its release onto the market, MPH abuse has been progressively increasing by individuals close to children treated with MPH and especially by patients to whom MPH is prescribed offlabel or obtained in black market. Objectives We report the results of a national survey on abuse and off-label use of methylphenidate. Methods Assessment of data collected between 2000 and 2011 from the Nots, OPPIDUM and OPEMA databases (tools for monitoring psychoactive substance misuse). Results MPH abuse and misuse were identified in 245 patients (168 in NotS, 68 in Oppidum and 9 in Opema). In NotS database, subjects were predominantly males (65%), aged between 12 and 74 years. When specified (122 cases), the sustained release form was used in 83% of cases and maximum daily MPH intake reached 2520 mg. MPH was injected (20%) or snorted (4%). Polydrug use was noted in 77% of cases. Regarding Oppidum and Opema databases, patients were exclusively adults and supported for drug addiction. In these cases, MPH was obtained by medical prescription (61%) and/or in black market (36%). Conclusion The medical practice of off-label prescription of MPH to treat ADHD or drug addiction in adults is the main problem in France. Another new aspect is that MPH is also diverted by teenagers, with or without ADH, for its stimulant and concentration-enhancing properties.

Warnings over rise in prescriptions for methylphenidate, as use of cognitive enhancers becomes common among students

Increased prescribing of methylphenidate has led the Care Quality Commission (CQC) to warn that supplies of the drug might be being diverted and misused as cognitive enhancers. The drug is commonly used to treat attention deficit hyperactivity disorder, but the CQC warned about potential misuse of the drug in its annual report on controlled drugs.1 The report says that the CQC is “aware of the possibility that methylphenidate could be diverted and …

Five-fold increase in national prevalence rates of attention-deficit/hyperactivity disorder medications for children and adolescents with autism spectrum disorder, attention-deficit/hyperactivity disorder, and other psychiatric disorders: a Danish register-based study.

The purpose of this study was to estimate the prevalence and time trends in prescriptions of methylphenidate, dexamphetamine, and atomoxetine in children and adolescents, within three diagnostic groups: 1) autism spectrum disorder (ASD), 2) attention-deficit/hyperactivity disorder (ADHD), and 3) other psychiatric disorders. Data from six different national registers were used and merged to identify a cohort of all children and adolescents born in Denmark between 1990 and 2001 (n=852,711). Sociodemographic covariates on cohort members and their parents and lifetime prescriptions of methylphenidate, dexamphetamine, and atomoxetine were extracted from the registers. Prescriptions were also stratified by duration (<6 months. vs.≥ 6 months). Sixteen percent of 9698 children and adolescents with ASD (n=1577), 61% of 11,553 children and adolescents with ADHD (n=7021) and 3% of 48,468 children and adolescents with other psychiatric disorders (n=1537) were treated with one or more ADHD medications. There was a significant increase in prescription rates of these medications for all three groups. From 2003 to 2010, youth 6-13 years of age with ASD, ADHD, and other psychiatric disorders had 4.7-fold (4.4-4.9), 6.3-fold (6.0-6.4), and 5.5-fold (5.0-5.9) increases, respectively, in prescription rates of ADHD medications. This is the largest study to date assessing stimulant treatment in children and adolescents with ASD, and is the first prospective study quantifying the change over time in the prevalence of treatment with ADHD medications in a population-based national cohort of children and adolescents with ASD. The prevalence of stimulant treatment in youth with ASD of 16% is consistent with earlier studies. The past decade has witnessed a clear and progressive increase in the prescription rates of medications typically used to treat ADHD in children and adolescents in Denmark. This increase is not limited to only those with ADHD, but includes others with neuropsychiatric disorders, including ASD. The risks and benefits of this practice await further study.

Assessment of Methylphenidate Prescriptions Written for the Treatment of Attention Deficit Hyperactivity Disorder

Aim: Methylphenidate is a medication used for the treatment of attention deficit hyperactivity disorder (ADHD). In this study, we aimed to investigate the details of methylphenidate prescriptions.Materials and Methods: A total of 5681 methylphenidate prescriptions written for the treatment of ADHD were collected from the archives of the Provincial Health Directorate of Istanbul between January and December 2009 and were retrospectively evaluated regarding the details of drug usage. Statistical comparisons were based on the Chi-square test at a p<0.05 level of significance.Results: The ages of the patients were not mentioned in most of the methylphenidate prescriptions (85.4%). Out of those prescriptions with age information, 78.5% were written for patients younger than 18 years old. Methylphenidate prescriptions were mainly written for male patients (73.7%). Sixty three percent of methylphenidate prescriptions were written by pediatric and adolescent psychiatrists as well as pediatricians. Methylphenidate prescriptions for pediatric patients were more often written in university hospitals (64.5%), whereas those for adult patients were more often written in private hospitals (36.6%). Doctors treating pediatric patients more often mentioned dosage information than doctors treating adult patients (p<0.01). Methylphenidate prescriptions for pediatric patients were more often written in winter, whereas the majority of those for adult patients were written in summer (p<0.01).Conclusion: It was interesting to note that a remarkable percentage of adult patients get methylphenidate treatment although these prescriptions are written most often for pediatric patients. The findings of this study point out that methylphenidate treatment in adult patients should be more thoroughly evaluated and resolved.

703 – Methylphenidate abuse among icelandic i.v. substance abusers

Background Prescription and sale of Methylphenidate (MPD) has increased sharply in Iceland in recent years as it has done worldwide. MPD is known to have abuse potential but significant i.v. use of prescription stimulants has not been reported in the literature. Clinical experience however has indicated that such i.v. use has now become very prevalent in Iceland. Aim To investigate the prevalence, pattern and symptoms of i.v. MPD abuse in Iceland. Method The study is cross-sectional in design. The study tool is a semi-structured interview designed especially for the purpose of this study. All substance abusers admitted to drug treatment in Iceland who have used substances i.v. in the past 30 days, are offered to participate in the study. The aim is to include 150 individuals. Result The study is in its preliminary stage. First results show that MPD is now the most commonly abused i.v. drug in Iceland, 85% of the sample admitted to using MPD i.v. in the past 30 days. Methylphenidate is preferred by i.v. substance abusers over illegal stimulants. Conclusion Our preliminary data shows that MPD abuse is a very prevalent problem in Iceland. It is the most commonly abused i.v. drug in Iceland at present. It is important to objectively verify and characterize the pattern of MPD abuse as to evaluate the complications associated with i.v. use of MPD. Increased knowledge of this problem is necessary both for Iceland as well as other countries.

Persistence of pharmacological treatment into adulthood, in UK primary care, for ADHD patients who started treatment in childhood or adolescence.

BackgroundADHD guidelines in the UK suggest that children and adults who respond to pharmacological treatment should continue for as long as remains clinically effective, subject to regular review. To what extent patients persist with treatment from childhood and adolescence into adulthood is not clear. This study aims to describe, in UK primary care, the persistence of pharmacological treatment for patients with ADHD who started treatment aged 6–17 years and to estimate the percentage of patients who continued treatment from childhood and adolescence into adulthood.MethodsThe Health Improvement Network (THIN) database was used to identify patients with ADHD who received their first prescription for methylphenidate/ dexamfetamine/atomoxetine, aged 6–17 years. Patients were monitored until their ‘censored date’ (the earliest of the following dates: date the last prescription coded in the database ended, end of the study period (31st December 2008), date at which they transferred out of their practice, date of death, the last date the practice contributed data to the database). Persistence of treatment into adulthood was estimated using Kaplan Meier analysis.Results610 patients had follow-up data into adulthood. 213 patients (93.4% male) started treatment between 6–12 years; median treatment duration 5.9 years. 131 (61.5%) stopped before 18 years, 82 (38.5%) were still on treatment age ≥18 years. 397 patients (86.4% male) started treatment between 13–17 years; median treatment duration was 1.6 years. 227 (57.2%) stopped before 18 years, 170 (42.8%) were still on treatment age ≥18 years. The number of females in both age categories was too small to formally test for differences between genders in persistence of treatment.ConclusionPersistence of treatment into adulthood is lower (~40%) compared with published rates of persistence of the condition (~65% when symptomatic definition of remission used). Due to the limited number of patients with data past 18 years, it is important that ongoing monitoring of prescribing into later adulthood is undertaken, particularly to observe the effects of recommendations in new guidelines.

Safety of Attention-Deficit/Hyperactivity Disorder Medications in Children: An Intensive Pharmacosurveillance Monitoring Study

Our intensive pharmacosurveillance monitoring program was performed to increase the number of adverse drug reactions (ADRs) recorded in the Italian spontaneous reporting database, and to systematically collect more thorough data about atomoxetine (ATX) and methylphenidate (MPH) safety in the pediatric setting. From September 2007 to October 2010, 1841 youth were enrolled in the Italian Attention- Deficit/Hyperactivity Disorder Register, but we report here on the 76 children from the five Reference Prescription Centers in Campania, an Italian region where we administered our systematic adverse event checklist. Among our cohort, 68 children received a prescription of ATX and 8 received a prescription of MPH. Most children were male and between 10 and 13 years of age, had a diagnosis of attention-deficit/hyperactivity disorder-combined (ADHD-C) and had learning disability as the main comorbidity. Most ADRs reported to the Italian spontaneous reporting database occurred in patients from Campania. Twenty-five experienced at least 1 ADR for a total of 40 ADRs reported to the Italian drug agency. Most ADRs were common and not serious, and resolved completely. Weight loss was the most frequently reported ADR. Only two ADRs were unexpected and only one was uncommon. Sixteen ADRs resulted in permanent drug withdrawal. Based on the Naranjo algorithm, 25 ADRs were considered "probable" and 15 were considered "possible." Although our data provide reassurance of the safety of ATX and MPH, several unexpected or uncommon ADRs (hepatomegaly, suicidal ideation, weight gain, or drug interactions) were identified by our intensive pharmacosurveillance monitoring program. Our results show that an intensive pharmacosurveillance monitoring program that involves pharmacovigilance centers and clinicians can improve the collection of information on drug safety in children.

Drug Treatment Patterns of Attention-Deficit/Hyperactivity Disorder in Children and Adolescents in Germany: Results from a Large Population-Based Cohort Study

Despite a substantial increase in total methylphenidate (MPH) prescriptions in Germany over the last 20 years, and the introduction of modified release MPH (MR MPH) and atomoxetine (ATX), remarkably little is known about treatment patterns of attention- deficit/hyperactivity disorder (ADHD) in individual patients. Usage patterns of ADHD drugs in children and adolescents in Germany were analyzed using data from one large German health insurance including >7,200,000 members. Of those, 6210 ADHD patients newly diagnosed in 2005 were followed for a maximum of 4 years. Kaplan-Meier estimates were calculated for onset and discontinuation of ADHD drug treatment. Predictors of time until drug treatment initiation were assessed by Cox regression. During follow-up, 52.0% of ADHD subjects (53.4% of boys, 47.5% of girls) received ADHD drug treatment. The majority of them (91.6%) were started on MPH, with immediate release MPH (IR MPH) being the initial treatment choice in 75.3%. In these subjects, change to drug treatment with MR MPH in the first year occurred in 48% by switch or addition. Significant predictors of drug treatment were behavioral and emotional disorders (HR=1.13; 95% CI 1.03-1.24) and a diagnosis of ADHD with conduct disorder (HR=1.21, 95% CI 1.12-1.32), whereas young age showed a protective effect. After 6, 12, and 24 months of treatment initiation, 22.4%, 43.4%, and 66.3% of treated girls, and 17.8%, 36.1%, and 54.1% of treated boys had discontinued ADHD treatment. Drug treatment of ADHD was relatively common in Germany and more frequent in boys than in girls. IR MPH was the predominant treatment choice at treatment initiation. Approximately 20% of treated subjects discontinued drug treatment within the first 6 months, with girls stopping drug treatment earlier than boys. The reasons for early drug discontinuation need to be further explored.

Overlapping Prescriptions of Stimulants for Children and Adolescents With Attention-Deficit Hyperactivity Disorder

The study aimed to assess the occurrence of overlapping prescriptions for methylphenidate among children and adolescents with newly diagnosed attention-deficit hyperactivity disorder (ADHD) and to evaluate the extent to which physician-level and patient-level characteristics affected the risk of prescription overlap during a one-year treatment period. The analytic sample comprised 3,081 incident cases of ADHD in 2002 involving children aged 17 years or younger from a retrospective cohort study in Taiwan. Medical and pharmacy claims data from 1999 to 2002 were retrieved from the National Health Insurance Program. All records of methylphenidate prescriptions within a year of treatment initiation were retrieved for each patient, and the number of overlapping days for any two successive prescriptions (new, renewal, or refill) was measured. Multilevel analyses were performed to identify predictors of methylphenidate prescription overlap. Within a year of treatment initiation, approximately 3% to 4% individuals with a new diagnosis of ADHD had experienced methylphenidate prescription overlap. Youngsters who resided in a rural region (adjusted odds ratio [AOR]=2.68) or who had ever changed prescribing doctors (AOR=3.04) were more likely to have visits with a methylphenidate prescription overlap. Receiving methylphenidate from physicians aged 46 or older was associated with 3.6-fold increased odds of prescription overlap. In an effort to improve the quality and safety of prescription of controlled substances in younger populations, interventions or policies should be devised to target both the service providers and the patients.

Phosphates and Behavioral Abnormalities

In their review article, Ritz et al. described the consequences of hyperphosphatemia caused by phosphate additives in food with regard to increased renal and cardiovascular morbidity and mortality (1). I want to add that phosphates for some time have been suspected of being associated with behavioral abnormalities. The doctor and children’s book author Heinrich Hoffmann described in his character of Fidgety Philip not only a child in whom nowadays attention deficit hyperactivity disorder (ADHD) would be diagnosed, but he also adds that “a normal human being has only 1.5/1000 phosphorus in their brain”, and wonders if it should be investigated whether “any fellow who was happy as a lark did not carry two or three times of that amount in his head” (2). The association of phosphorus and behavioral abnormalities has been the subject of a controversial discussion ever since, and in ADHD, a low-phosphate diet has been recommended. However, only recently, several clinical studies have suggested an association between (organo-)phosphates and ADHD (3, 4). Bearing in mind the rising incidence of ADHD and increasing numbers of prescriptions for methylphenidate, it would be interesting to study the association between dietary components such as in fast food and processed food with a high phosphate content and a causal association with the development of ADHD.

Methylphenidate prescription: Important recommendations to mitigate dependence

Methylphenidate prescription: Important recommendations to mitigate dependence

The epidemiology of pharmacologically treated attention deficit hyperactivity disorder (ADHD) in children, adolescents and adults in UK primary care

BackgroundAttention Deficit Hyperactivity Disorder (ADHD) is a common neurodevelopmental disorder characterised by the symptoms of inattention, impulsivity and hyperactivity. ADHD was once perceived as a condition of childhood only; however increasing evidence has highlighted the existence of ADHD in older adolescents and adults. Estimates for the prevalence of ADHD in adults range from 2.5–4%. Few data exist on the prescribing trends of the stimulants methylphenidate and dexamfetamine, and the non-stimulant atomoxetine in the UK. The aim of this study was to investigate the annual prevalence and incidence of pharmacologically treated ADHD in children, adolescents and adults in UK primary care.MethodsThe Health Improvement Network (THIN) database was used to identify all patients aged over 6 years with a diagnosis of ADHD/hyperkinetic disorder and a prescription for methylphenidate, dexamfetamine or atomoxetine from 2003–2008. Annual prevalence and incidence of pharmacologically treated ADHD were calculated by age category and sex.ResultsThe source population comprised 3,529,615 patients (48.9% male). A total of 118,929 prescriptions were recorded for the 4,530 patients in the pharmacologically treated ADHD cohort during the 6-year study. Prevalence (per 1000 persons in the mid-year THIN population) increased within each age category from 2003 to 2008 [6–12 years: from 4.8 (95% CI: 4.5–5.1) to 9.2 (95% CI: 8.8–9.6); 13–17 years: from 3.6 (95% CI: 3.3–3.9) to 7.4 (95% CI: 7.0–7.8); 18–24 years: from 0.3 (95% CI: 0.2–0.3) to 1.1 (95% CI: 1.0–1.3); 25–45 years: from 0.02 (95% CI: 0.01–0.03) to 0.08 (95% CI: 0.06–0.10); >45 years: from 0.01 (95% CI: 0.00–0.01) to 0.02 (95% CI: 0.01–0.03). Whilst male patients aged 6-12 years had the highest prevalence; the relative increase in prescribing was higher amongst female patients of the same age - the increase in prevalence in females aged 6–12 years was 2.1 fold compared to an increase of 1.9 fold for their male counterparts. Prevalence of treated ADHD decreased with increasing age. Incidence (per 1000 persons at risk in the mid-year THIN population) was highest for children aged 6–12 years.ConclusionsA trend of increasing prescribing prevalence of ADHD drug treatment was observed over the period 2003–2008. Prevalence of prescribing to adult patients increased; however the numbers treated are much lower than published estimates of the prevalence of ADHD. This study has added to the limited knowledge on ADHD prescribing in primary care, particularly in the area of drug treatment in adulthood.

Peut-on prescrire des psychostimulants chez un étudiant sain ? Exemple d’un cas clinique

Neuroenhancement is an anglo-saxon concept concerning the use of stimulating psychotropic drugs by healthy subjects, outside any established medical indication or festive setting, to achieve an improvement of their mental functioning. In 2009, because of increasing requests for neuroenhancement in USA, the American Association of Neurology has published practical recommendations stating that "it is ethically permissible to prescribe medications for neuroenhancement" if a number of conditions is met. We present these ethical and psychopharmacological conditions ("the inverted U-Shape principle" in which cognitive performance is related to catecholamine levels and "the trade-off principle" to cognitive enhancement) through a clinical case of methylphenidate prescription in a healthy 24 years old medical student, preparing for the "examen classant national" (the French national ranking before postgraduate education). We then discuss anglo-saxon ethical context in which these recommendations have been proposed.

ADHD Medications and Risk of Serious Cardiovascular Events in Young and Middle-aged Adults

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. 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. 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). 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. 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. 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.

Differences in Methylphenidate Use Between Immigrants and Spaniards in the Child Population of Aragon, Spain

The aim of this research is to study the differences in methylphenidate use in children from different ethnic groups in the region of Aragon, Spain. Differences in the use of methylphenidate between both groups of children, immigrants and Spanish nationals, were assessed based on the total number of methylphenidate prescriptions made out for all children in Aragon in 2008 (N = 98 837). We have used defined daily doses and the defined daily doses per 1000 inhabitants per day. Defined daily doses per 1000 inhabitants per day of methylphenidate use was 18.49 in Spanish boys compared with 2.70 in immigrant boys, and 5.48 in Spanish girls versus 0.83 in immigrant girls. All differences between groups were statistically significant (P < .001). This study confirms that methylphenidate use is higher in a local population than in an immigrant population. Western European and North American children show the highest use, followed by Latin Americans and Eastern Europeans.